Expression of 32/67-kDa laminin receptor in laminin adhesion-selected human colon cancer cell lines.
Kim WH. Lee BL. Jun SH. Song SY. Kleinman HK.
Department of Pathology, Seoul National University College of Medicine and Cancer Research Center, Korea.
Laminin promotes the malignant phenotype, and the expression of certain laminin receptors is increased in malignancy. Previously, we demonstrated that a laminin-adhesive subclone of a human colon cancer cell line showed increased tumorigenicity in nude mice and increased affinity of the beta1 integrin for laminin relative to the laminin-non-adhesive subclone. The total amount of either beta1 integrin protein or mRNA did not increase. As levels of the 32/67-kDa laminin receptor (67LR) correlate with malignancy, we examined 67LR expression in the laminin adhesion-selected human colon cancer cells. The laminin-adhesive subclone, which was more tumorigenic in both heterotopic and orthotopic locations than in a laminin-non-adhesive subclone, showed cell-surface membrane staining of 67LR, whereas the laminin-non-adhesive subclone showed cytoplasmic staining of 67LR. No difference in either the amount of 67LR mRNA or the amount of protein was observed in the parental cells than in the laminin-adhesive and non-adhesive subclones. When assayed on a laminin affinity column, more 67LR molecules bound to the column with cell extracts from the laminin-adhesive subclone than was observed with the non-adhesive subclone. These findings suggest that the increased tumorigenicity of laminin adhesion-selected tumour cells might be due to an alteration in the distribution and/or adhesiveness of multiple receptors including 67LR and beta1 integrin.
Cyclin D1 overexpression related to retinoblastoma protein expression as a prognostic marker in human oesophageal squamous cell carcinoma.
Ishikawa T. Furihata M. Ohtsuki Y. Murakami H. Inoue A. Ogoshi S.
Department of Surgery II, Kochi Medical School, Japan.
The relationship between aberrant expression of cyclin D1 and retinoblastoma (RB) protein and clinicopathological factors was investigated in 80 patients with oesophageal SCC using immunohistochemical analyses. Heterogeneous staining of cancer cell nuclei with antibody to cyclin D1 was found in 31.3% of patients (25 out of 80 patients). Nuclear staining of cancer cells with anti-RB antibody was homogeneous in 10.0% (8 out of 80 patients) and heterogeneous in 58.8% (47 out of 80 patients). Among cases with homogeneous staining for RB protein, 75% (six out of eight patients) exhibited simultaneous positivity for cyclin D1 (P < 0.05). No significant relationship was found between cyclin D1 or RB protein expression and various clinicopathological parameters. The prognosis of patients with cyclin D1-positive tumours was significantly poorer than that of the other patients (P < 0.01). In addition, when patients with cyclin D1-positive and -negative tumours were stratified according to presence or absence of lymph node metastasis and RB status, the cumulative survival rates in the cyclin D1-positive groups were significantly lower for patients without lymph node metastasis (P < 0.01) and for patients whose tumours were positive for RB (P< 0.0001). These findings suggest the possibility that cyclin D1 positivity is a useful prognostic marker related to lymph node metastasis and RB protein expression in human oesophageal SCC, in addition to clinicopathological factors.
Overexpression of the rhoC gene correlates with progression of ductal adenocarcinoma of the pancreas.
Suwa H. Ohshio G. Imamura T. Watanabe G. Arii S. Imamura M. Narumiya S. Hiai H. Fukumoto M.
Department of Pathology, Graduate School of Medicine, Kyoto University, Japan.
It has been reported that the rho genes, which consist of a ras-related small GTPase protein family, regulate cytoskeletal structures and have the potential to transform cultured cells. To investigate the biological relevance of the rho genes in pancreatic carcinogenesis, we examined expressions of the rhoA, B and C genes by polymerase chain reaction after reverse transcription (RT-PCR) in 33 cases of ductal adenocarcinoma of the pancreas. In addition, mutations of the K-ras, rhoA, B and C genes were studied in the same series of tumour tissues to correlate with rho gene expressions. The expression levels of the rhoC gene were significantly higher in tumours than in non-malignant portions (P < 0.001). Metastatic lesions overexpressed the rhoC gene compared with primary tumours (P < 0.05). Carcinoma tissues with perineural invasion and lymph node metastasis exhibited significantly higher expressions of the rhoC gene than tumours without these manifestations (P < 0.001 and P < 0.05 respectively). Overexpression of the rhoC gene significantly correlated with poorer prognosis of patients with pancreatic adenocarcinoma (P < 0.05). In contrast, the expression levels of the rhoA and B genes showed no significant relationship with clinicopathological findings. Mutation was not found either in the rhoA, B or C gene sequences examined. K-ras gene mutation, detected in 27 out of 33 (81.8%) cases, did not affect the expression levels in any of the rho genes. These suggest that elevated expression of the rhoC gene may be involved in the progression of pancreatic carcinoma independent of K-ras gene activation.
Phase I study on docetaxel and ifosfamide in patients with advanced solid tumours.
Pronk LC. Schrijvers D. Schellens JH. de Bruijn EA. Planting AS. Locci-Tonelli D. Groult V. Verweij J. van Oosterom AT.
Rotterdam Cancer Institute (Dr Daniel den Hoed Kliniek) and University Hospital Rotterdam, The Netherlands.
Docetaxel and ifosfamide have shown significant activity against a variety of solid tumours. This prompted a phase I trial on the combination of these drugs. This phase I study was performed to assess the feasibility of the combination, to determine the maximum tolerated dose (MTD) and the side effects, and to propose a safe schedule for further phase II studies. A total of 34 patients with a histologically confirmed solid tumour, who were not pretreated with taxanes or ifosfamide and who had received no more than one line of chemotherapy for advanced disease were entered into the study. Treatment consisted of docetaxel given as a 1-h infusion followed by ifosfamide as a 24-h infusion (schedule A), or ifosfamide followed by docetaxel (schedule B) every 3 weeks. Docetaxel doses ranged from 60 to 85 mg m(-2) and ifosfamide doses from 2.5 to 5.0 g m(-2). Granulocytopenia grade 3 and 4 were common (89%), short lasting and ifosfamide dose dependent. Febrile neutropenia and sepsis occurred in 17% and 2% of courses respectively. Non-haematological toxicities were mild to moderate and included alopecia, nausea, vomiting, mucositis, diarrhoea, sensory neuropathy, skin and nail toxicity and oedema. There did not appear to be any pharmacokinetic interaction between docetaxel and ifosfamide. One complete response (CR) (soft tissue sarcoma) and two partial responses (PRs) were documented. A dose of 75 mg m(-2) of docetaxel combined with 5.0 g m(-2) ifosfamide appeared to be manageable. Schedule A was advocated for further treatment.
Analysis of histological therapeutic effect, apoptosis rate and p53 status after combined treatment with radiation, hyperthermia and 5-fluorouracil suppositories for advanced rectal cancers.
Sakakura C. Koide K. Ichikawa D. Wakasa T. Shirasu M. Kimura A. Taniguchi H. Hagiwara A. Yamaguchi T. Inazawa J. Abe T. Takahashi T. Otsuji E.
First Department of Surgery, Kyoto Prefectural University of Medicine, Japan.
The tumour-suppressor gene p53 encodes a transcription factor that plays a critical role in the induction of G1 cell cycle arrest and apoptosis after DNA damage. To clarify the role of the p53 gene and apoptosis in combined hyperthermia, chemotherapy and radiation (hyperthermochemoradiotherapy, HCR therapy) for rectal cancer, we examined the histological response, rate of apoptosis, DNA fragmentation and p53 status in tumours from 28 patients undergoing HCR therapy before surgery and from 22 patients who did not have preoperative treatment. The therapeutic effect of HCR therapy was closely correlated with the rate of apoptosis; the correlation was statistically significant, suggesting that this effect occurs through apoptosis. The incidence of p53 mutations in the treated group were as follows: in tumours resistant to HCR therapy, four of seven (57.1%); intermediately sensitive, 7 of 13 (53.9%); or sensitive, three of eight (37.5%), suggesting that the therapeutic effect and apoptosis rate were related to the p53 status of the tumours to some extent, but the relation was not statistically significant. In the 22 control tumours (non-treated group), the apoptosis rate was 2.0 +/- 1.1%, and there was no significant difference in p53 status compared with the HCR group. Our study indicates that the pathological response to HCR therapy correlates with the rate of apoptosis with statistical significance and that it induces the therapeutic effect more significantly in rectal cancer cells with wild-type p53, although HCR therapy-induced apoptosis also occurs in some rectal cancers with mutated p53. Therefore, this combination therapy can induce an additive or synergistic anti-tumour effect in rectal cancers with wild-type p53 as well as in those with mutated p53 through apoptosis, offering new therapeutic opportunities and a better prognosis.
Family history of cancer and risk of colorectal cancer in Italy.
Negri E. Braga C. La Vecchia C. Franceschi S. Filiberti R. Montella M. Falcini F. Conti E. Talamini R.
Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Subjects with a family history of colorectal cancer (CRC) are at increased risk of CRC, but quantification of the risk in different populations, the possible differences in risk according to localization of the cancer and the association of family history of other cancers with CRC risk are still open issues. We have therefore analysed data from a multicentric case-control study conducted in six Italian areas between 1992 and 1996 of 1225 incident cases of colon cancer, 728 cases of rectal cancer and 4154 controls admitted for acute conditions to the same network of hospitals as the cases. Unconditional logistic regression models including terms for gender, age, study centre, years of education and number of siblings were used to estimate the odds ratios (ORs) of CRC according to various aspects of history of CRC and other cancers in first-degree relatives. The OR for family history of CRC was 3.2 (95% confidence interval, CI, 2.5-4.1) for colon cancer and 2.2 (95% CI 1.6-3.1) for rectal cancer. Colon cancer was significantly associated with a family history of stomach (OR 1.4), bone (OR 2.1) and kidney (OR 2.3) cancers, while rectal cancer was significantly associated with a family history of lymphomas (OR 2.8). There was a 30% higher risk of colon and rectal cancer in subjects with a family history of any cancer, excluding intestine. The ORs for family history of CRC were 5.2 for colon and 6.3 for rectum when the proband's age was below 45 years. The ORs were similar when the affected relative was a parent or a sibling and in different strata of age of relative(s). For subjects with two or more first-degree relatives with CRC, the risk was 6.9 for the right colon, 5.8 for the transverse and descending colon, 3.8 for the sigma, 3.2 for the rectosigmoid junction and 1.9 for the rectum. This study confirms that a family history of CRC in first-degree relatives increases the risk of both colon and rectal cancer, the association being stronger at younger ages and for right colon.
Comparison of p53 and DNA content abnormalities in adenocarcinoma of the oesophagus and gastric cardia.
Gleeson CM. Sloan JM. McManus DT. Maxwell P. Arthur K. McGuigan JA. Ritchie AJ. Russell SE.
Department of Medical Genetics, The Queen's University of Belfast, Belfast City Hospital, N Ireland, UK.
This study examined the association between 17p allelic loss, p53 gene mutation, p53 protein expression and DNA aneuploidy in a series of adenocarcinomas arising in the oesophagus and gastric cardia. 17p allelic loss was detected in 79% (15 of 19) of oesophageal and in 83% (29 of 35) of gastric adenocarcinomas. p53 mutations were detected in 70% (14 of 20) and 63% (26 of 41) of oesophageal and of gastric adenocarcinomas respectively. Both tumour types were associated with a predominance of base transitions at CpG dinucleotides. In five cases of oesophageal adenocarcinoma, the same mutation was detected both in tumour and in adjacent dysplastic Barrett's epithelium. Diffuse p53 protein expression was detected in 65% (13 of 20) and 59% (24 of 41) of oesophageal and of gastric tumours, respectively, and was associated with the presence of p53 missense mutation (Chi-squared, P < 0.0001). DNA aneuploidy was detected in 80% (16 of 20) of oesophageal and in 70% (28 of 40) of gastric tumours. No association was found between p53 or DNA content abnormalities and tumour stage or histological subtype. In conclusion, this study detected a similar pattern of p53 alterations in adenocarcinoma of the oesophagus and gastric cardia--molecular data consistent with the observation that these tumours demonstrate similar clinical and epidemiological features.
Alterations in plasminogen activation correlate with epithelial cell dysplasia grading in colorectal adenomas.
Protiva P. Sordat I. Chaubert P. Saraga E. Tran-Thang C. Sordat B. Blum AL. Dorta G.
Division of Gastroenterology, CHUV/PMU, University Hospital, Lausanne, Switzerland.
Proteases are important for neoplastic invasion but a specific role for the plasminogen activator system in the progression of colorectal epithelial dysplasia to adenomatous lesions remains unclear. Consecutive tissue cryosections of 51 adenomas, 49 distant mucosa samples and five mucosa samples from control subjects were histopathologically analysed for dysplasia grade and tissue type, urokinase plasminogen activator levels and plasminogen activator inhibitor type 1 (PAI-1) using immunosorbent methods. Plasminogen activation and urokinase-mediated proteolytic activity levels were assessed using in situ zymography. Plasminogen activation and tissue-type activator levels were lower in adenomas than in mucosae (P < 0.001). PAI-1 concentration and urokinase levels were higher in adenomas than in mucosae (P < 0.001 and P < 0.001 respectively). In adenomas, urokinase concentration increased in parallel with PAI-1, but only the urokinase levels correlated with the dysplasia grade (P < 0.01). Thus, the alterations in plasminogen activation correlated with epithelial cell dysplasia grading. In the mucosa to adenoma transition, a marked decrease in tissue-type plasminogen activator occurred. In adenomas, this decrease was accompanied by a concomitant increase in urokinase and PAI-1. The urokinase level only continued to rise in parallel with the dysplasia grade. Resulting protease-antiprotease imbalance in high-grade dysplasia may represent the phenotypic change associated with malignant transformation and invasive behaviour.
Are serial measurements of CA19-9 useful in predicting response to chemotherapy in patients with inoperable adenocarcinoma of the pancreas?
Gogas H. Lofts FJ. Evans TR. Daryanani S. Mansi JL.
Department of Oncology, St George's Hospital, London, UK.
Thirty-nine patients with inoperable adenocarcinoma of the pancreas were studied (27 male, 12 female; median age 60 years, range 39-75 years). All patients received chemotherapy with continuous infusion 5-fluorouracil with intravenous bolus epirubicin followed by cisplatin, repeated every 21 days for a total of six cycles and were evaluable for response. Serum CA19-9 concentrations were obtained at baseline and before each cycle. A rise or fall in the tumour marker was defined as a greater than 15% increase or decrease in the marker on two consecutive occasions 3 weeks apart. A plateau in the tumour marker was defined as a less than 15% decrease or increase on two occasions. Changes in marker expression were compared with serial computerized tomography scanning before treatment and after the third and sixth cycle of chemotherapy. Thirty-five of 39 patients had an elevated CA19-9 (87.9%). Thirteen (36.2%) exhibited a decrease, seven (19.4%) a plateau and 16 (44.4%) patients had a progressive rise in serum CA19-9. The sensitivity of CA19-9 was 67% for predicting a partial response and 86% for progressive disease. The median survival for the 13 patients exhibiting a reduction was 333 days, for the seven patients exhibiting a plateau 253 days and for those who had a progressive rise 185 days. The difference in median survival between the group of patients with > 15% decrease and those with > 15% increase of CA19-9 was significant (P = 0.001). In the cohort of patients who exhibited a reduction in CA19-9, no tumour progression was seen, and the reduction occurred during the first three cycles of treatment. Thus, interval scanning may be avoided in this group of patients.
Clinical course and prognostic factors following bone recurrence from breast cancer.
Coleman RE. Smith P. Rubens RD.
YCRC Department of Clinical Oncology, Weston Park Hospital, Sheffield, UK.
Three hundred and sixty-seven women presenting to the Breast Unit at Guy's Hospital between 1975 and 1990 whose first distant metastasis was in the skeleton were identified and the influence of a number of patient and tumour characteristics on the development and subsequent prognosis of bone metastases was assessed. One hundred and thirty-nine women had disease that remained clinically confined to the skeleton. They were more likely to be older, with lobular carcinoma and to have presented initially with little or no axillary lymph node involvement. The 228 women who subsequently developed disease at extra-osseus sites were more likely to have poorly differentiated ductal tumours and heavy lymph node involvement at primary diagnosis. On multivariate analysis, the clinical and pathological factors of greatest prognostic importance for survival after the development of bone metastases were histological grade (P = < 0.0001), oestrogen receptor status (P = < 0.0001), bone disease at initial presentation (P = < 0.0001), disease-free interval (P = 0.002) and age (P = 0.006).
Schedule-selective biochemical modulation of 5-fluorouracil in advanced colorectal cancer: a multicentric phase II study.
Aschele C. Guglielmi A. Frassineti GL. Milandri C. Amadori D. Labianca R. Vinci M. Tixi L. Caroti C. Ciferri E. Verdi E. Rosso R. Sobrero A.
Department of Medical Oncology, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy.
We have recently reported high clinical activity against advanced colorectal cancer of a regimen-alternating bolus FUra, modulated by methotrexate (MTX), and continuous infusion FUra, modulated by 6-s-leucovorin (6-s-LV). Considering the low toxicity of the bolus part of this regimen and our recent in vitro finding of a strong synergism between bolus FUra and natural-beta-IFN (n-beta-IFN), this cytokine was incorporated in the bolus part of our treatment programme. Fifty-six patients with untreated, advanced, measurable colorectal cancer were treated with two biweekly cycles of FUra bolus (600 mg m(-2)), modulated by MTX (24 h earlier, 200 mg m(-2)), and n-beta-IFN (3 x 10(6) IU i.m. every 12 h, starting at the time of FUra administration for four doses), alternating with a 3-week continuous infusion of FUra (200 mg m(-2) daily), modulated by 6-s-LV (20 mg m(-2) weekly bolus). After a 1-week rest, the whole cycle (8 weeks) was repeated if indicated. A total of 5 complete and 17 partial responses were obtained (response rate, 41%; 95% confidence limits, 28-55%) in 54 assessable patients. After a median follow-up time of 36 months, five patients are still alive. Overall, the median time to treatment failure was 6.4 months. The median duration of survival was 15.0 months. There was one treatment-related death after a course of MTX --> bolus FUra/n-beta-IFN and grade III-IV toxicity occurred in 18% of the patients. As the addition of n-beta-IFN results in high toxicity, whereas the efficacy seems to be similar to that of the same regimen without the cytokine, our groups are currently randomizing the original regimen, without IFN, against standard modulated bolus FUra.
Aberrant FHIT transcripts in hepatocellular carcinomas.
Chen YJ. Chen PH. Chang JG.
Department of Surgery, Taipei Medical College Hospital, Taiwan.
To study abnormalities of the FHIT gene in human hepatocellular carcinoma (HCC), eight liver cancer cell lines, 18 matched tumorous and non-tumorous tissues from patients with HCC and three normal liver tissues were analysed by microsatellite polymorphism analysis and reverse transcription of FHIT mRNA followed by polymerase chain reaction (PCR) amplification and sequencing of the products. No loss of heterozygosity at chromosome 3p14.2 as defined by markers D3S1300 and D3S1312 was detected in any of the specimens. In addition, a normal transcript of the gene without any sequence change was found to be expressed in all the cell lines, 17 of the 18 tumorous and all 21 non-tumorous liver tissues tested. Although five out of eight liver cancer cell lines (62.5%), 12 out of 18 HCC tissues (66.7%) and 8 out of 18 paired non-tumorous liver tissues (44.4%) displayed abnormal faint bands of smaller size, sequence analysis revealed that they were aberrant FHIT transcripts lacking three or more exons and might represent alternatively spliced transcripts only. In conclusion, these studies indicate that abnormalities of the FHIT gene transcripts occur in a fairly high frequency of tumorous and non-tumorous liver tissues. However, it might not be causally related to the hepatocarcinogenesis.
Characterization of dihydropyrimidine dehydrogenase in human colorectal tumours.
McLeod HL. Sludden J. Murray GI. Keenan RA. Davidson AI. Park K. Koruth M. Cassidy J.
Department of Medicine, University of Aberdeen, Foresterhill, UK.
Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme for degradation of 5-fluorouracil (5-FU). DPD activity is highly variable in liver and peripheral mononuclear cells (PMNCs) and it has not been well studied in human tumours. Characterization of DPD in colorectal cancer is of clinical interest through its role in the regulation of 5-FU, the main chemotherapeutic agent used in this disease. Therefore, DPD activity was analysed in colorectal tumour and adjacent normal tissue from 63 patients, including three liver metastasis. DPD activity was highly variable in all tissues studied (coefficient of variation 43-61%) and was higher in normal tissue than in tumour. The tumour-normal activity ratio ranged from 0.19 to 3.32 (median 0.76). PMNC DPD activity was available for 57 patients and was correlated with tumour activity (r(s) = 0.29, P < 0.001). A higher correlation was observed between PMNCs and tumour samples that were both obtained in the morning (r(s) = 0.49), consistent with circadian variation in DPD activity. Normal tissue DPD activity was not correlated with either tumour (r(s) = 0.11) or PMNC activity (r(s) = -0.06). This study provides the first analysis of DPD activity in colorectal cancer and illustrates the large degree of variation in tumour activity. The tumour-normal activity ratio results suggest that elevated tumour DPD can play a role in 5-FU resistance through increased inactivation in tumour cells, but is an uncommon event in colorectal tumours. The results support the use of PMNCs for monitoring tumour DPD activity, particularly when circadian variation is taken into account. As a large degree of the variation in tumour DPD activity is not explained by PMNC activity, more accurate alternatives are needed before DPD activity can be used for targeting 5-FU therapy.
Reduced expression of deleted colorectal carcinoma (DCC) protein in established colon cancers.
Goi T. Yamaguchi A. Nakagawara G. Urano T. Shiku H. Furukawa K.
The First Department of Surgery, Fukui Medical School, Japan.
Using a bacterial fusion protein, a deleted colorectal carcinoma (DCC)-specific monoclonal antibody (MAb) 127-22 was established. Although MAb 127-22 reacted with almost all normal tissues, it did not react or only weakly reacted with many cancer cell lines, including colonic cancer lines, in flow cytometry. In Western immunoblots, the MAb reacted with a single 190-kDa molecule in a myeloma line Ara-10 extract. This component was scarcely detected in colonic cancer cell lines. Immunoblots of samples from 25 pairs of colonic cancers and adjacent normal tissues and from five adenoma tissues revealed that all normal colonic and adenoma tissues significantly expressed the DCC protein, whereas colonic cancer tissues showed poor expression. These results indicate not only deletion of and lowered mRNA expression of the DCC gene, but also marked reduction of DCC protein occurred in colonic cancer tissues. In addition, colonic cancer patients with liver metastasis expressed significantly lower levels of DCC than those without, suggesting the prognostic value of DCC expression.
Emergency admission for cancer: a matter of survival?
Porta M. Fernandez E. Belloc J. Malats N. Gallen M. Alonso J.
Institut Municipal d'Investigacio Medica, Universitat Autonoma de Barcelona, Spain.
The objective of this study was to compare the pre-hospital health care process, clinical characteristics at admission and survival of patients with a digestive tract cancer first admitted to hospital either electively or via the emergency department. The study involved cross-sectional analysis of information elicited through personal interview and prospective follow-up. The setting was a 450-bed public teaching hospital primarily serving a low-income area of Barcelona, Catalonia, Spain. Two hundred and forty-eight symptomatic patients were studied, who had cancer of the oesophagus (n = 31), stomach (n = 70), colon (n = 82) and rectum (n = 65). The main outcome measures were stage, type and intention of treatment and time elapsed from admission to surgery; the relative risk of death was calculated using Cox's regression. There were 161 (65%) patients admitted via the emergency department and 87 (35%) electively. The type of physician seen at the first pre-hospital visit had more often been a general practitioner in the emergency than in the elective group (89% vs 75%, P < 0.01). Emergency patients had seen a lower number of physicians from symptom onset until admission, but two-thirds had made repeated visits to a primary care physician. Emergency patients were less likely to have a localized tumour and a diagnosis of cancer at admission, and surgery as the initial treatment. Median survival was 30 months for elective patients and 8 months for emergency patients (P < 0.001), and the relative risk of death (RR) was 1.83 (95% confidence interval, CI, 1.32-2.54). After adjustment for strong prognostic factors, emergency patients continued to experience a significant excess risk (RR = 1.58; CI 1.10-2.27). In conclusion, in digestive tract cancers, admission to hospital via the emergency department is a clinically important marker of a poorer prognosis. Emergency departments can only partly counterbalance deficiencies in the effectiveness of and integration among the different levels of the health system.
Dihydropyrimidine dehydrogenase pharmacogenetics in patients with colorectal cancer.
Ridge SA. Sludden J. Wei X. Sapone A. Brown O. Hardy S. Canney P. Fernandez-Salguero P. Gonzalez FJ. Cassidy J. McLeod HL.
Department of Medicine and Therapeutics, Institute of Medical Sciences, University of Aberdeen, Foresterhill, UK.
Individuals with a deficiency in the enzyme dihydropyrimidine dehydrogenase (DPD) may experience severe life-threatening toxicity when treated with 5-fluorouracil (5-FU). As routine measurement of enzyme activity is not practical in many clinical centres, we have investigated the use of DNA mutation analysis to identify cancer patients with low enzyme levels. We have identified two new mutations at codons 534 and 543 in the DPD cDNA of a patient with low enzyme activity and screened the DNA from 75 colorectal cancer patients for these mutations and the previously reported splice site mutation (Vreken et al, 1996; Wei et al, 1996). In all cases, DPD enzyme activity was also measured. The splice site mutation was detected in a patient (1 out of 72) with low enzyme activity whereas mutations at codons 534 (2 out of 75) and 543 (11 out of 23) were not associated with low enzyme activity. These studies highlight the need to combine DPD genotype and phenotype analysis to identify mutations that result in reduced enzyme activity.
A 15-year series of gastrointestinal non-Hodgkins lymphomas: a population-based study.
Ducreux M. Boutron MC. Piard F. Carli PM. Faivre J.
Registre des Tumeurs Digestives, Faculte de Medecine, Dijon, France.
Data from the Registry of Digestive tumours of the Departement of Cote d'Or (France) were used to study the characteristics of gastrointestinal non-Hodgkin's lymphomas in the 1976-90 period. The mean annual age-standardized incidence rate was 0.94 per 100,000 for men, and 0.54 per 100,000 for women. Incidence varied little during the study period. Overall 5-year survival rate was 34.3 +/- 5.6%.
Inhibitors of aromatase prevent degradation of the enzyme in cultured human tumour cells.
Harada N. Hatano O.
Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi, Japan.
The effects of two steroidal (4-hydroxyandrostenedione and atamestane) and three non-steroidal (fadrozole, vorozole and pentrozole) aromatase inhibitors on the levels of aromatase mRNA and protein were examined using cultured JEG-3 and HepG2 cells. Immunocytochemical studies demonstrated increased quantities of immunoreactive aromatase in both cell types as a result of these treatments. To clarify this effect in detail, quantitation of aromatase protein in JEG-3 cells was performed after various treatments using an enzyme-linked immunosorbent assay. Time-dependent increase was observed with all the aromatase inhibitors except 4-hydroxyandrostenedione. The three non-steroidal agents caused an approximately fourfold elevation in the cells 24 h after the treatment compared with untreated controls. The inhibitors also appeared to block the rapid degradation observed in JEG-3 cells after induction with forskolin. However, aromatase mRNA levels in JEG-3 cells remained unchanged. Furthermore, the increase in aromatase protein in JEG-3 cells due to the inhibitor action was not blocked by treatment with cycloheximide, an inhibitor of protein synthesis. These results thus suggest that aromatase inhibitors increase aromatase protein through stabilization and reduced protein turnover as a side-effect of their binding.
Detection of the DCC gene product in normal and malignant colorectal tissues and its relation to a codon 201 mutation.
Schmitt CA. Thaler KR. Wittig BM. Kaulen H. Meyer zum Buschenfelde KH. Dippold WG.
I Department of Internal Medicine, Johannes-Gutenberg-University, Mainz, Germany.
Protein expression of the putative tumour-suppressor gene DCC on chromosome 18q was evaluated in a panel of 16 matched colorectal cancer and normal colonic tissue samples together with DCC mRNA expression and allelic deletions (loss of heterozygosity, LOH). Determined by a polymerase chain reaction (PCR)-LOH assay, 12 of the 16 (75%) cases were informative with LOH occurring in 2 of the 12 cases. For DCC mRNA, transcripts could be detected in all analysed normal tissues (eight out of eight) by RT-PCR, whereas 6 of the 15 tumours were negative. DCC protein expression, investigated by immunohistochemistry using the monoclonal antibody 15041 A directed against the intracellular domain, was homogeneously positive in all normal tissue samples. In tumour tissues, no DCC protein was seen in 11 out of 16 samples (69%). For the DCC codon 201, we found a loss of a wild-type codon sequence caused by mutation or LOH in at least 8 out of 15 cases (53%) compared with the corresponding normal tissue. DCC protein expression was undetectable in eight of the nine tumours missing both wild-type codons. Only one of the five tumours with retained DCC protein expression had no detectable wild-type codon 201. In addition, 9 out of 15 normal tissue specimens were mutated in codon 201. In two out of three cases with homozygous wild-type codons in peripheral blood lymphocyte (PBL) DNA, mutations were already observed in the tumour adjacent normal colonic mucosa. We conclude that DCC immunostaining should be introduced in the clinicopathological routine because of its strong correlation with the known prognostic markers 18q LOH and mutation of codon 201.
Aberrant expression and phosphorylation of beta-catenin in human colorectal cancer.
Takayama T. Shiozaki H. Doki Y. Oka H. Inoue M. Yamamoto M. Tamura S. Shibamoto S. Ito F. Monden M.
Department of Surgery II, Osaka University Medical School, Suita, Japan.
The cytoplasmic domain of cadherins is known to associate with the intracellular proteins, catenins, which link cadherins to the actin-based cytoskeleton. In this study, we immunohistochemically investigated the expression of beta-catenin as well as E-cadherin and alpha-catenin in 86 human colorectal cancers, and we analysed their coexpression pattern and relationship to clinicopathological factors. In cancerous tissues, the frequency of reduced expression of beta-catenin (28 of 86, 33%) was similar to that of E-cadherin (19 of 86, 22%), but less than that of alpha-catenin (47 of 86, 55%). All three molecules were expressed strongly, as was the normal epithelium, in 36 cases (42%), whereas the rest (50 cases, 58%) showed reduction in one of the molecules. The reduction of beta-catenin expression was significantly correlated with dedifferentiation, Duke's stage, lymph node metastasis and liver metastasis. Next, we examined tyrosine phosphorylation in the protein complex immunoprecipitated with E-cadherin, as E-cadherin function is down-regulated by receptor-type tyrosine kinase in vitro. It was of interest that up-regulation of tyrosine phosphorylation of beta-catenin was more frequently observed in cancerous tissues than in the matching normal mucosa. These results suggest that beta-catenin may have important regulatory roles within an E-cadherin-mediated adhesion system in human colorectal cancers.
Comparative studies on the expression of somatostatin receptor subtypes, outcome of octreotide scintigraphy and response to octreotide treatment in patients with carcinoid tumours.
Nilsson O. Kolby L. Wangberg B. Wigander A. Billig H. William-Olsson L. Fjalling M. Forssell-Aronsson E. Ahlman H.
Department of Pathology, Sahlgrenska University Hospital, University of Gothenburg, Goteborg, Sweden.
We have compared the expression of somatostatin receptor (sstr) subtypes with the outcome of somatostatin receptor scintigraphy and the effect of somatostatin receptor activation in patients with disseminated carcinoid tumours. Tumour tissues from nine patients with midgut carcinoids (ileal) and three patients with foregut carcinoids (gastric, thymic) were analysed using Northern blotting. Expression of somatostatin receptors was demonstrated in all tumours (12 out of 12), with all five receptor subtypes present in 9 out of 12 tumours. Somatostatin receptor scintigraphy using [111In]DTPA-D-Phe1-octreotide visualized tumours in all patients (12 out of 12). The 111In activity concentrations in tumour tissue (T) and blood (B) were determined in three tumours 1-7 days after injection of the radionuclide. The T/B 111In activity concentration ratios ranged between 32 and 651. Clinically, treatment with the long-acting somatostatin analogue octreotide resulted in marked symptom relief accompanied by a significant reduction in tumour markers, for example urinary-5-HIAA levels (28-71% reduction). Incubation of midgut carcinoid tumours in primary culture with octreotide (10 microM) resulted in a reduction in spontaneously secreted serotonin (45-71% reduction) and 5-HIAA (41-94% reduction). The results demonstrate that carcinoid tumours possess multiple somatostatin receptor subtypes and that somatostatin analogues such as octreotide, which preferentially bind to somatostatin receptor subtype 2 and 5, can be used in the diagnosis and medical treatment of these tumours. In the future, novel somatostatin analogues with subtype specific receptor profiles may prove to be of value for individualizing the treatment of disseminated carcinoid tumour disease.
The effect of different chemotherapeutic agents on the enrichment of DNA mismatch repair-deficient tumour cells.
Fink D. Nebel S. Norris PS. Aebi S. Kim HK. Haas M. Howell SB.
Department of Medicine and the Cancer Center, University of California at San Diego, La Jolla 92093-0058, USA.
Loss of DNA mismatch repair is a common finding in hereditary non-polyposis colon cancer as well as in many types of sporadic human tumours. We compared the effect of loss of DNA mismatch repair on drug sensitivity as measured by a clonogenic assay with its effect on the ability of the same drug to enrich for mismatch repair-deficient cells in a proliferating tumour cell population. Mixed populations containing 50% DNA mismatch repair-deficient cells constitutively expressing green fluorescent protein and 50% mismatch repair-proficient cells were exposed to different chemotherapeutic agents. 6-Thioguanine, to which DNA mismatch repair-deficient cells are known to be resistant, was included as a control. The results in the cytotoxicity assays and in the enrichment experiments were concordant. Treatment with either carboplatin, cisplatin, doxorubicin, etoposide or 6-thioguanine resulted in enrichment for mismatch repair-deficient cells, and clonogenic assays demonstrated resistance to these agents, which varied from 1.3- to 4.8-fold. Treatment with melphalan, paclitaxel, perfosfamide or tamoxifen failed to enrich for mismatch repair-deficient cells, and no change in sensitivity to these agents was detected in the clonogenic assays. These results identify the topoisomerase II inhibitors etoposide and doxorubicin as additional agents for which loss of DNA mismatch repair causes drug resistance. The concordance of the results from the two assay systems validates the enrichment assay as a rapid and reliable method for screening for the effect of loss of DNA mismatch repair on sensitivity to additional drugs.
The effects of n-6 polyunsaturated fatty acids on the expression of nm-23 in human cancer cells.
Jiang WG. Hiscox S. Bryce RP. Horrobin DF. Mansel RE.
University Department of Surgery, University of Wales College of Medicine, Heath Park, Cardiff, UK.
This study examined the effect of n-6 polyunsaturated fatty acids (PUFAs) on the expression of nm-23, a metastasis-suppressor gene, in two highly invasive human cancer cell lines, HT115 and MDA MB 231. A range of n-6 and n-3 PUFAs were tested. We report that while linoleic acid and arachidonic acid reduced the expression of nm-23-H1, gamma linolenic acid (GLA) and its soluble lithium salt markedly increased the expression of the molecules. The stimulation of the expression of nm-23 by GLA was seen at both protein and mRNA levels. Up-regulation of nm-23 was also associated with a reduction of the in vitro invasiveness of these cells. It is concluded that gamma linolenic acid (GLA) enhances the expression of nm-23. This contributes to the inhibition of the in vitro invasion of tumour cells.
2-(4-Aminophenyl)benzothiazoles: novel agents with selective profiles of in vitro anti-tumour activity.
Bradshaw TD. Wrigley S. Shi DF. Schultz RJ. Paull KD. Stevens MF.
Department of Pharmaceutical Sciences, University of Nottingham, UK.
2-(4-Aminophenyl)benzothiazole (CJM 126) elicits biphasic growth-inhibitory effects against a panel of oestrogen receptor-positive (ER+) and oestrogen receptor-negative (ER-) human mammary carcinoma cell lines in vitro, yielding IC50 values in the nM range. Substitutions adjacent to the amino group in the 2-phenyl ring with a halogen atom or methyl group enhance potency in sensitive breast lines (pM IC50 values). Transient biphasic dose responses were induced but rapidly eradicated after specific drug exposure periods. Two human prostate carcinoma cell lines were refractory to the growth-inhibitory properties of 2-(4-aminophenyl)benzothiazoles; IC50 values > 30 microM were obtained. Potency and selectivity were confirmed when compounds were examined in the National Cancer Institute's Developmental Therapeutics screen; the spectrum of activity included specific ovarian, renal, colon as well as breast carcinoma cell lines. Moreover, comparing 6-day and 48-h incubations, the exposure time-dependent nature of the biphasic response was corroborated. Differential perturbation of cell cycle distribution followed treatment of MCF-7 and MDA 468 cells with substituted 2-(4-aminophenyl)benzothiazoles. In MDA 468 populations only, accumulation of events in G2/M phase was observed. Two MCF-7 cell lines were established with acquired resistance to CJM 126 (IC50 values > 20 microM), which exhibit cross-resistance to substituted benzothiazoles, but equal sensitivity to tamoxifen and doxorubicin. Compared with standard anti-tumour agents evaluated in the National Cancer Institute in vitro cell panel, benzothiazoles revealed unique profiles of growth inhibition, suggesting a mode(s) of action shared with no known clinically active class of chemotherapeutic agents.
Molecular pathogenesis of sporadic duodenal cancer.
Achille A. Baron A. Zamboni G. Orlandini S. Bogina G. Bassi C. Iacono C. Scarpa A.
Istituto di Anatomia Patologica, Universita di Verona, Italy.
Whether duodenal adenocarcinoma should be considered as a gastrointestinal or as a peripancreatic cancer is a matter of debate, as is the opportunity and type of treatment. We investigated 12 such cancers for the genetic anomalies involved in the pathogenesis of gastrointestinal malignancies, including (a) those occurring in common-type cancers - allelic losses at chromosomes 3p, 5q, 17p and 18q, and Ki-ras and p53 alterations; and (b) those characteristic of mutator-phenotype cancers - microsatellite instability and TGF-betaRII gene mutations. We found Ki-ras and p53 mutations in five (42%) and eight cancers (67%), respectively; chromosome 3p, 5q, 17p and 18q allelic losses in two of nine (22%), six of ten (60%), six of nine (67%) and three of ten (30%) informative cancers, respectively. Finally, three cancers (25%) showed widespread microsatellite instability and two of them had a TGF-betaRII gene mutation. Our data suggest that duodenal cancers may arise from either of the two known pathogenetic molecular pathways of gastric and colorectal cancers. The majority of our cases were highly aggressive cancers with frequent chromosomal changes and p53 mutations as observed in the common-type gastrointestinal malignancies, while widespread subtle alterations characteristic of mutator-phenotype cancers occurred in a minority, which also showed a favourable long-term outcome.
p53 mutation is a poor prognostic indicator for survival in patients with hepatocellular carcinoma undergoing surgical tumour ablation.
Honda K. Sbisa E. Tullo A. Papeo PA. Saccone C. Poole S. Pignatelli M. Mitry RR. Ding S. Isla A. Davies A. Habib NA.
Department of Surgery, Hammersmith Hospital, RPMS, London, UK.
Forty-two patients with hepatocellular carcinoma (HCC) were resected and their tumours were analysed for p53 mutations by GC-clamped denaturing gradient gel electrophoresis (DGGE), single-strand conformation polymorphism (SSCP) and gene sequencing. All the exons have been analysed in this study. Eight of 12 HCCs with cirrhosis due to viral hepatitis and the two patients with sarcomatoid changes displayed p53 mutations. In contrast, no mutation was observed in the fibrolamellar variant (n = 9), non-cirrhotics (n = 13) and alcoholic cirrhosis (n = 6). The mutations observed were in exons 5-8. Two mutations were observed in codons 136 and 213 as well as a T insertion between residues 156 and 157 (exon 5) and these are reported for the first time in HCC. Likewise, the silent mutation polymorphism in codon 213 was noticed in 3 of the 42 patients. Survival analysis of these patients after surgery showed the mean and median survival in patients with wild-type p53 to be 60 and 43 months respectively. In the group with p53 mutations, the mean and median survival was 15 and 12 months. The difference was statistically significant (P= 0.003).
Dose-limiting neurotoxicity in a phase I study of penclomedine (NSC 388720, CRC 88-04), a synthetic alpha-picoline derivative, administered intravenously.
Jodrell DI. Bowman A. Stewart M. Dunlop N. French R. MacLellan A. Cummings J. Smyth JF.
ICRF Medical Oncology Unit, Western General Hospital, Edinburgh.
3,5-Dichloro-2,4-dimethoxy-6-(trichloromethyl)pyridine (penclomedine, NSC 338720, CRC 88-04) is an alpha-picoline derivative with anti-tumour activity in preclinical models. Penclomedine administration by 1-h intravenous infusion on 5 consecutive days was repeated 3 weekly in the absence of dose-limiting toxicity (DLT) or disease progression. Five dose levels were investigated (22.5-340 mg m(-2) day[-1]). Eight men and eight women were entered, median age 59 years (range 39-73 years), with good performance status (ECOG 0/1) in 11 patients. A total of 13 out of 16 patients had received previous chemotherapy. Common toxicity criteria grade (CTCg) II vomiting was recorded at all dose levels. Neurotoxicity (cerebellar ataxia and dizziness) was the DLT, CTCg III toxicity occurring in three out of three patients treated at 340 mg m(-2) day(-1). CTCg III dizziness was noted in one out of three patients at 250 mg m(-2) day(-1). Neurotoxicity developed during the 1-h infusion and persisted for a variable period (maximum 5 h) after infusion. Prophylactic antiemetic drugs appeared to reduce associated vomiting but did not prevent ataxia. No antiproliferative toxicities were noted and no anti-tumour responses were documented. Penclomedine pharmacokinetic studies confirmed preclinical evidence of extensive apparent distribution (93 l m[-2]) and rapid clearance (41 l h[-1] m[-2]). Purkinje cell loss has been identified in preclinical models after intraperitoneal administration (O'Reilly et al, 1996a) and further clinical development of penclomedine will focus on oral administration.
N-acetyl transferase 1: two polymorphisms in coding sequence identified in colorectal cancer patients.
Hubbard AL. Moyes C. Wyllie AH. Smith CA. Harrison DJ.
Sir Alastair Currie CRC Laboratories, Department of Pathology, University of Edinburgh, Medical School, UK.
Increased cancer risk has been associated with functional polymorphisms that occur within the genes coding for the N-acetyltransferase enzymes NAT1 and NAT2. We detected two NAT1 polymorphisms in colorectal cancer patients by heteroduplex analysis. DNA sequencing revealed the wild-type sequence (NAT1*4) and two single base substitutions at adjacent positions 999 bp (C to T, NAT1*14) and 1000 bp (G to A, NAT1*15) of the gene, changing Arg187 to a stop codon and Arg187 to Gln respectively. NAT1 alleles NAT1*4 (0.98) and NAT1*15 (0.02) were present at a similar frequency in patients with colorectal cancer (n=260) and in a Scottish control group (n=323). The third allele, NAT1*14, was present only in the colorectal cancer group at a frequency of 0.006. NAT1 genotype NAT1*4/ NAT1*15 was significantly less frequent in individuals that had a slow NAT2 genotype. This was observed in both cancer and control groups and suggests that this association was unrelated to cancer risk. We conclude that polymorphisms within the coding region of the NAT1 gene are infrequent and do not appear to have an independent association with colorectal cancer risk. However, the relationship between NAT1 and NAT2 polymorphisms appears non-random, suggesting a linkage between these enzymes.
Systematic heterogeneity and prognostic significance of cell proliferation in colorectal cancer.
Palmqvist R. Oberg A. Bergstrom C. Rutegard JN. Zackrisson B. Stenling R.
Department of Pathology, Umea University, Sweden.
The prognosis of colorectal cancer has not significantly changed during the last 30 years. While evaluation of tumour cell proliferation may provide prognostic information, results obtained so far have been contradictory Heterogeneity in tumour cell proliferation may explain these contradictions. With in vivo injection of iododeoxyuridine (IdUrd), estimation of labelling index (LI), S-phase transit time (Ts) and potential doubling time (Tpot) may be performed from a single sample. A total of 109 colorectal cancers were studied after in vivo injection of IdUrd before surgical removal. From each cancer, four to eight samples were processed for both flow cytometrical (FCM) and immunohistochemical (IHC) visualization of IdUrd incorporation. LI/IHC was morphometrically quantified at both the luminal border and the invasive margin of these tumours. LI was significantly higher at the luminal border compared with the invasive margin, although they were correlated with each other. Using combined IHC and FCM methods, rapidly growing colorectal cancers (high LI and/or low Tpot) showed an increased survival (significant for LI at the invasive margin and for Tpot at both the invasive margin and the luminal border) in the entire unselected material and for radically removed Dukes' B tumours. FCM data alone did not discriminate for survival, with the exception of Ts in diploid and radically removed Dukes' B tumours.
Raltitrexed (Tomudex): an alternative drug for patients with colorectal cancer and 5-fluorouracil associated cardiotoxicity.
Kohne CH. Thuss-Patience P. Friedrich M. Daniel PT. Kretzschmar A. Benter T. Bauer B. Dietz R. Dorken B.
Department of Haematology/Oncology and Tumor Immunology Robert-Rossle-Klinik, Virchow-Klinikum, Medizinische Fakultat Charite der Humboldt-Universitat zu Berlin, Germany.
Two patients with proven 5-fluorouracil (5-FU)-associated cardiotoxicity were treated with the specific thymidylate synthase inhibitor raltitrexed safely, without evidence of cardiotoxicity. Raltitrexed might be an alternative for patients with advanced colorectal cancer and 5-FU-associated cardiotoxicity. 5-FU cardiotoxicity is not due to the antineoplastic mechanisms via thymidilate synthase.
Vascular endothelial growth factor (VEGF) mRNA isoform expression pattern is correlated with liver metastasis and poor prognosis in colon cancer.
Tokunaga T. Oshika Y. Abe Y. Ozeki Y. Sadahiro S. Kijima H. Tsuchida T. Yamazaki H. Ueyama Y. Tamaoki N. Nakamura M.
Department of Pathology, Tokai University School of Medicine, Isehara, Kanagawa, Japan.
Vascular endothelial growth factor (VEGF) is a well known factor that induces angiogenesis. Four isoforms, i.e. VEGF206, 189, 165, and 121, have been identified. We examined the isoform patterns of VEGF mRNA using reverse transcription polymerase chain reaction (RT-PCR) analysis in 61 colon cancers. All the colon cancers examined expressed VEGF121. The isoform patterns were classified into three groups: type 1, VEGF121; type 2, VEGF121 + VEGF165; type 3, VEGF121 + VEGF165 + VEGF189. Three of the 61 colon cancers examined showed type 1 expression, 26 showed type 2 expression and 32 showed the type 3 pattern. The patients with liver metastases showed the type 3 isoform expression pattern at a significantly higher incidence (12 of 16, 75%) than those without liver metastasis (20 of 45, 44%) (P=0.036). The type 3 isoform pattern was significantly associated with M1 stage (P=0.019). The patients with colon cancer and the type 3 isoform pattern showed significantly poor prognosis (P < 0.01, Cox-Mantel). The colon cancers with the type 3 pattern showed a significantly higher involvement of veins (P=0.006). These observations suggest that the aberrant type 3 expression pattern of VEGF189 mRNA isoforms is correlated with liver metastasis, M stage, and poor prognosis in colon cancer.
Chromosome division figures reveal genomic instability in tumorigenesis of human colon mucosa.
Department of Oncology and Pathology, Karolinska Institute and Hospital, Stockholm, Sweden.
A variety of chromosomal gains and losses has been detected with comparative genomic hybridization during tumorigenesis in the colon mucosa. The aim of this investigation was to corroborate increasing genomic instability and to elucidate those lesions in which the record from comparative genomic hybridization has remained unexpectedly negative. Replicate paraffin-embedded samples were investigated in detail using image microphotometry. Crucial to the recent approach was the fact that the histological compartments were exactly matched and that the single-cell measurements were highly accurate (CV at 0.05). Feulgen DNA was quantified in interphase nuclei and chromosome division figures, which were found in all cases of high-grade dysplasia and, with increased frequency, of colon carcinoma. The genomic imbalance in chromosome division figures was quantified by the sensitive 4.5 c exceeding rate (where c is the haploid genome equivalent), which was also positive in cases with a negative record from comparative genomic hybridization. The DNA content of chromosome division figures was measured with a mean 4.5 c exceeding rate of 25.8 +/- 4.4% standard error in 12 cases of high-grade dysplasia and of 62.1 +/- 7.1% in colon carcinoma (16 cases). The chromosome division figures were considered to be the first morphological manifestation of genomic instability attending precancerous conditions in the colon. Telophase-like chromosome division figures with unequal amounts of DNA in their hemispheres revealed gross somatic mutations before clonal selection.
Enhanced expression of cytochrome P450 in stomach cancer.
Murray GI. Taylor MC. Burke MD. Melvin WT.
Department of Pathology, University of Aberdeen, Foresterhill, UK.
The cytochromes P450 have a central role in the oxidative activation and detoxification of a wide range of xenobiotics, including many carcinogens and several anti-cancer drugs. Thus the cytochrome P450 enzyme system has important roles in both tumour development and influencing the response of tumours to chemotherapy. Stomach cancer is one of the commonest tumours of the alimentary tract and environmental factors, including dietary factors, have been implicated in the development of this tumour. This type of tumour has a poor prognosis and responds poorly to current therapies. In this study, the presence and cellular localization of several major forms of P450, CYP1A, CYP2E1 and CYP3A have been investigated in stomach cancer and compared with their expression in normal stomach. There was enhanced expression of CYP1A and CYP3A in stomach cancer with CYP1A present in 51% and CYP3A present in 28% of cases. In contrast, no P450 was identified in normal stomach. The presence of CYP1A and CYP3A in stomach cancer provides further evidence for the enhanced expression of specific forms of cytochrome P450 in tumours and may be important therapeutically for the development of anti-cancer drugs that are activated by these forms of P450.
Interleukin 2 restores CD3-zeta chain expression but fails to generate tumour-specific lytic activity in tumour-infiltrating lymphocytes derived from human colorectal hepatic metastases.
Yoong KF. Adams DH.
Liver Research Laboratories, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK.
Metastatic colorectal cancer is usually progressive despite infiltration of the tumours by T lymphocytes, suggesting that these tumour-infiltrating lymphocytes (TILs) are functionally deficient. Recently, TILs from other tumours have been shown to express reduced levels of the T-cell receptor signal-transducing CD3-zeta chain. We were interested to determine whether a similar abnormality existed in TILs from human colorectal hepatic metastasis (CHM) and, if so, whether correcting the abnormality in vitro would restore anti-tumour activity and provide support for the development of immunotherapy for colorectal hepatic metastases. Twelve of 19 TILs from colorectal hepatic metastases were successfully expanded in vitro in high-dose recombinant interleukin 2 (rlL-2) and their specific anti-tumour cytolytic activity was determined. CD3-positive (CD3+) TILs were HLA-Drhigh and CD69high, suggesting that they had been activated by exposure to antigen but expressed low levels of CD25, CD71 and the nuclear proliferation antigen Ki-67. Furthermore, they showed reduced expression of CD3-zeta compared with autologous peripheral blood T cells (PBTs) and failed to proliferate in the absence of high-dose rIL-2. Expansion of TILs in rIL-2 resulted in restoration of CD3-zeta expression and the ability to lyse K562 and Daudi cells but not autologous tumour cells. The absence of autologous tumour-specific cytolytic T-cell (CTL) activity may be due to the poor immunogenicity of colorectal tumour cells, which we found expressed only low levels of MHC I antigens and CD54 and failed to express MHC II antigens or the co-stimulatory molecules CD80, CD86 or CD106. The inability of rIL-2 to generate tumour-specific CTLs despite restoration of CD3-zeta expression and the presence of an intact lytic mechanism suggests that successful immunotherapy may require the development of strategies to increase the immunogenicity of this tumour.
Anthracycline doses in patients with liver dysfunction: do UK oncologists follow current recommendations?
Dobbs NA. Twelves CJ.
Imperial Cancer Research Fund Medical Oncology Unit, Churchill Hospital, Headington, Oxford, UK.
The question of whether UK oncologists follow current anthracycline dose modifications when treating patients with liver dysfunction was addressed through a questionnaire. Oncologists were asked the dose of doxorubicin or epirubicin they would prescribe for a woman with breast cancer and liver metastases who had one of four different patterns of abnormal liver chemistry. In each case, the median dose of anthracycline that would have been prescribed was close to that currently recommended. There was, however, wide variation in the dose that oncologists said they would prescribe, some avoiding an anthracycline altogether, whereas others would give full-dose treatment. Medical oncologists would prescribe a significantly lower dose of anthracycline than clinical oncologists for a patient with the most severely disturbed liver tests. Overall, medical oncologists were also significantly more likely to prescribe epirubicin. These results show the need for new, widely accepted anthracycline dose modifications for patients with liver dysfunction.
FEP regimen (epidoxorubicin, etoposide and cisplatin) in advanced gastric cancer, with or without low-dose GM-CSF: an Italian Trial in Medical Oncology (ITMO) study.
Bajetta E. Di Bartolomeo M. Carnaghi C. Buzzoni R. Mariani L. Gebbia V. Comella G. Pinotti G. Ianniello G. Schieppati G. Bochicchio AM. Maiorino L.
ITMO, c/o Division of Medical Oncology B of Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
The new regimens developed over the last few years have led to an improvement in the treatment of advanced gastric cancer, and our previous experience confirmed the fact that the combination of etoposide, doxorubicin and cisplatin (EAP regimen) is an active treatment that leads to interesting complete remission rates. The primary end point of the present multicentre, randomized, parallel-group phase II study was to determine the activity of the simplified 2-day EAP schedule in patients with locally advanced or metastatic gastric cancer, and to verify whether the addition of low doses of granulocyte-macrophage colony-stimulating factor (GM-CSF) made it possible to increase dose intensity. Of the 62 enrolled patients, 30 were randomized to receive epirubicin 35 mg m(-2), etoposide 120 mg m(-2) and cisplatin 45 mg m(-2) (FEP) on days 1 and 2 every 28 days and 32 to receive the same schedule plus subcutaneous GM-CSF (molgramostin) 150 microg day(-1) on days 5-14 every 21 days. The patients were stratified by age and the number of disease sites. The characteristics of the patients were well balanced between the two groups. The objective response rate of the patients as a whole was 34% (21 out of 62; 95% confidence interval 22-46), with only one complete remission. The median response duration was 4.5 months (range 1-24 months). The median time to treatment failure was 5 months (range 1-14 months), without any difference between the two groups. The median survival of the patients as a whole was 9 months. Full doses were administered in 92% and 94% of the cycles in the control and GM-CSF arms respectively. The average dose intensity calculated for all drugs was 0.96% in the control and 1.27% in the GM-CSF group. CTC-NCI grade 3-4 neutropenia was reported in 39% vs 45% of patients, thrombocytopenia in 11% vs 35% (P = 0.020) and anaemia in 7% vs 35% (P = 0.014). The FEP combination is as active (OR: 34%) in the treatment of patients with advanced gastric cancer as the EAP regimen, although it leads to fewer complete remissions. The patients randomized to receive low-dose GM-CSF achieved a significantly higher dose intensity than controls (P = 0.0001).
NM23-H1 immunostaining is inversely associated with tumour staging but not overall survival or disease recurrence in colorectal carcinomas.
Cheah PY. Cao X. Eu KW. Seow-Choen F.
Department of Colorectal Surgery, Singapore General Hospital, Republic of Singapore.
The NM23-H1 gene product has been recently identified as a potential metastasis suppressor. Studies on breast carcinomas have shown an inverse correlation between NM23-H1 status and stage of carcinogenesis and overall survival. However, in colorectal cancer, conflicting data have been reported. This study aimed to investigate whether NM23-H1 immunostaining is correlated with tumour stage, overall survival, disease recurrence, tumour differentiation, age and sex in colorectal carcinomas for the Singapore population using chi-square analysis. The staining was performed on 141 paraffin-embedded surgical specimens collected between 1991 and 1992 using a monoclonal anti-NM23-H1 antibody. Follow-up of patients was until time of death or for 5 years. There was a very significant inverse association between tumour staging and NM23-H1 status (P = 0.0004). However, NM23-H1 expression was not significantly correlated to overall 5-year survival, disease recurrence, tumour differentiation, age or sex. Thus, although NM23-H1 may be involved in suppressing metastasis, NM23-H1 immunohistochemistry has no prognostic value in colorectal cancer. This is the first report of a significant inverse association of NM23-H1 status with tumour staging in colorectal cancer which showed no correlation with overall survival or disease recurrence. Our result thus cautions against the practice of equating an inverse relation of genetic markers with tumour staging to survival or disease recurrence.
Absence of stimulation of poly(ADP-ribose) polymerase activity in patients predisposed to colon cancer.
Cristovao L. Lechner MC. Fidalgo P. Leitao CN. Mira FC. Rueff J.
Department of Genetics, Faculty of Medical Sciences, New University of Lisbon, Portugal.
Poly(ADP-ribose)polymerase (PARP) has been implicated in DNA repair mechanisms and the associated activity shown to markedly increase after DNA damage in carcinogen-treated cells. A defective DNA repair has been associated to the aetiology of human cancers. In order to assess the potential role of this enzyme in cellular response to DNA damage by gamma-radiation, we studied the activity of PARP in patients with familial adenomatous polyposis (FAP). We compared poly(ADP-ribose)polymerase activity by the rate of incorporation of radioactivity from [3H]adenine-NAD+ into acid-insoluble material in permeabilized leucocytes from FAP patients and healthy volunteers. Concomitantly, the intracellular levels of NAD+--the substrate for the PARP--and the reduced counterpart NADH were determined using an enzymatic cycling assay 30 min after [60Co] gamma-ray cells irradiation. Our results demonstrate that a marked stimulation of PARP activity is produced upon radiation of the cells from healthy subjects but not in the FAP leucocytes, which concomitantly show a marked decrease in total NAD-/NADH content. Our observations point to a role of PARP in the repair of the gamma-radiation-induced DNA lesions through a mechanism that is impaired in the cells from FAP patients genetically predisposed to colon cancer. The differences observed in PARP activation by gamma-radiation in patients and healthy individuals could reflect the importance of PARP activity dependent on treatment with gamma-rays. The absence of this response in FAP patients would seem to suggest a possible defect in the role of PARP in radiation-induced DNA repair in this cancer-prone disease.
Comparison of antiemetic efficacy of granisetron and ondansetron in Oriental patients: a randomized crossover study.
Poon RT. Chow LW.
Department of Surgery, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
A double-blind randomized crossover trial was performed to compare the antiemetic efficacy of two 5-HT3 receptor antagonists, granisetron and ondansetron, in Chinese patients receiving adjuvant chemotherapy (cyclophosphamide, methotrexate and 5-fluorouracil) for breast cancer. Twenty patients were randomized to receive chemotherapy with either granisetron on day 1 and ondansetron on day 8 of the first cycle followed by the reverse order in the second cycle, or vice versa. The number of vomiting episodes and the severity of nausea in the first 24 h (acute vomiting/nausea) and the following 7 days (delayed vomiting/nausea) were studied. Acute vomiting was completely prevented in 29 (72.5%) cycles with granisetron and 27 (67.5%) cycles with ondansetron, and treatment failure (>5 vomiting episodes) occurred in two (5%) cycles with each agent (P = NS). Acute nausea was completely controlled in 15 (37.5%) cycles with granisetron and 14 (35%) cycles with ondansetron, whereas severe acute nausea occurred in four (10%) cycles with each agent (P = NS). However, complete response for delayed vomiting was observed in only 21 (52.5%) cycles with granisetron and 22 (55%) cycles with ondansetron (P = NS), and delayed nausea was completely controlled in only 11 (27.5%) and ten (25%) cycles respectively (P = NS). In conclusion, both granisetron and ondansetron are effective in controlling acute nausea and vomiting in Chinese patients, with equivalent antiemetic efficacy. Control of delayed nausea and vomiting is less satisfactory.
In oesophageal squamous cell carcinoma vascular endothelial growth factor is associated with p53 mutation, advanced stage and poor prognosis.
Uchida S. Shimada Y. Watanabe G. Tanaka H. Shibagaki I. Miyahara T. Ishigami S. Imamura M.
Department of Surgery & Surgical Basic Science, Graduate School of Medicine, Kyoto University, Japan.
Vascular endothelial growth factor (VEGF) affects malignant tumours by promoting angiogenesis. The tumour-suppressor gene p53 has been thought to regulate VEGF. We investigated the effect of VEGF on oesophageal carcinoma and the connection between VEGF and p53. One hundred and nine resected oesophageal squamous cell carcinomas were examined. VEGF expression was analysed by immunohistochemical staining. Sixty-five tumours (59.6%, 65 out of 109) were classified as VEGF positive. A significant correlation was found between the VEGF expression and both the depth of invasion (P = 0.0001) and lymph node metastasis (P < 0.0001). With regard to p53, we compared the expression of VEGF with the mutation of p53, examined using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct sequencing in tumour samples obtained from 36 patients who we have reported previously. The VEGF expression was significantly correlated to p53 mutation (P = 0.0291). To evaluate the angiogenesis, microvascular density (MVD) was counted, and endothelial cells were stained immunohistochemically using anti-CD34 monoclonal antibody against 29 cases with invasion limited to the submucosal layer. The average MVD had a tendency to correlate to VEGF expression (P = 0.1626). The prognoses of patients with VEGF-positive primary tumours were significantly worse than for those with VEGF-negative primary tumours (P = 0.0077). We have assumed that VEGF contributes to aggressive characteristics in oesophageal carcinomas and that VEGF expression might be affected by p53 status.
The detection of K-ras mutations in colorectal cancer using the amplification-refractory mutation system.
Fox JC. England J. White P. Ellison G. Callaghan K. Charlesworth NR. Hehir J. McCarthy TL. Smith-Ravin J. Talbot IC. Snary D. Northover JM. Newton CR. Little S.
Zeneca Diagnostics, Northwich, Cheshire, UK.
A total of 301 colorectal carcinoma (CRC) archival samples were analysed using the amplification-refractory mutation system (ARMS). Each sample was examined to determine the mutation status of codons 12 and 13 of the K-ras oncogene. The results from direct DNA sequence analysis carried out on 30 of the samples differed from the ARMS result in almost 50% of the cases as a result of the relative excess of wild-type to mutated DNA sequences. To assess the validity of the ARMS data, the polymerase chain reaction (PCR) was used to generate an amplicon from K-ras exon 1 from 23 of the samples. The PCR amplicons were cloned and sequenced, and the DNA sequence analysis of the cloned material was in agreement with the ARMS results in all but one case. This case represented a tumour that exhibited a five-nucleotide reversed inversion. The cloned sequence data confirm the sensitivity and specificity of the individual ARMS reactions and that it is possible in certain cases to detect additional, more complex, sequence variations.
Cytokeratin 20 mRNA in peripheral venous blood of colorectal carcinoma patients.
Funaki NO. Tanaka J. Ohshio G. Onodera H. Maetani S. Imamura M.
Department of Surgery, Shiga Medical Center for Adult Diseases, Moriyama City, Japan.
A highly sensitive system was previously developed by us to detect the presence of colorectal carcinoma cells in blood in the form of cytokeratin 20 (CK20) mRNA. In the present study, we used an improved version of this system to analyse the peripheral blood of 28 patients with colorectal carcinoma, five patients with non-cancerous intestinal diseases and six normal controls for the presence or absence of CK20 mRNA and to investigate the relationship between the mRNA results and prognosis. All eight patients with recurrence were positive for CK20 mRNA, as were four patients in the Dukes' C stage with either distant metastasis or dissemination. Five of the nine patients in the Dukes' C stage with neither distant metastasis nor dissemination were positive, and three of these developed recurrence within 11 months after the analysis. Only one of the seven patients in the Dukes' A or B stage was positive, and none showed recurrence during the 1-19 months of observation. None of the five patients without carcinomas or of the six normal controls was positive. Although the follow-up period is limited and the recurrences were all local at present, these results suggest that the presence of CK20 mRNA in circulation may be a useful indicator for the screening of advanced colorectal carcinoma patients with a high risk of recurrence.
Apparent lack of prognostic value of MIB-1 index in anal carcinomas treated by radiotherapy.
Allal AS. Alonso-Pentzke L. Remadi S.
Division of Radiation Oncology, University Hospital of Geneva, Switzerland.
This study was conducted to investigate the influence of Mib-1 index on outcome in 55 patients with T1-4 anal carcinomas treated radically by radiotherapy (RT) alone (24) or by concomitant chemo-radiotherapy (31). Median follow-up for surviving patients was 94 months (range 17-179 months). Tissue materials were obtained from pretreatment biopsies. A modified immunoperoxidase technique consisting of microwave heating of routinely processed material was employed using the Mib-1 antibody (Immunotech, 1:50). The median Mib-1 index for all patients was 53% (range 18-96%). Subgroups of patients with high vs low Mib-1 indices (separated by the median value) had statistically similar outcomes regarding 5-year overall survival (64% vs 65% P = 0.7), locoregional control (77% vs 69%, P = 0.5) and disease-free survival (73% vs 66%, P = 0.5). Moreover, no significant association was found between mean Mib-1 indices and various clinicopathological parameters studied (age, sex, circumferential tumour extent, T-stage, N-stage and histological type). In conclusion, Mib-1 index failed to predict the outcome of patients with anal carcinomas treated conservatively by radiotherapy with or without chemotherapy. It is noteworthy that the median Mib-1 index observed in anal carcinomas in this study was among the highest yet reported for cancers of epithelial origin.
Chromosomal imbalances in primary and metastatic pancreatic carcinoma as detected by interphase cytogenetics: basic findings and clinical aspects.
Zojer N. Fiegl M. Mullauer L. Chott A. Roka S. Ackermann J. Raderer M. Kaufmann H. Reiner A. Huber H. Drach J.
First Department of Internal Medicine, University of Vienna, Austria.
To date, cytogenetic studies on pancreatic carcinoma are rare, and little is known about the frequency of cytogenetic aberrations in primary carcinomas compared with metastatic tumour cells. We therefore evaluated the frequency of chromosomal aberrations in 12 primary pancreatic carcinomas and in effusion specimens from 25 patients with pancreatic cancer by using interphase fluorescence in situ hybridization (FISH) and a panel of four centromeric probes. Hyperdiploidy and chromosomal imbalances, predominantly affecting chromosome 8, were a constant finding in metastatic effusion cells, whereas concordant gain of chromosomes or relative loss of chromosome 18 characterized primary pancreatic carcinomas. The potential role of oncogenes located on chromosome 8 for pancreatic cancer progression was further investigated by double-hybridization studies of aneuploid effusion cells with a probe to 8q24 (MYC) and a centromeric probe to chromosome 8, which demonstrated amplification of the MYC oncogene in two of ten cases (20%). Finally, a potential application of basic findings in the clinical setting was tested by searching for micrometastatic cells in effusions from pancreatic cancer patients primarily negative by FISH. Two-colour FISH in combination with extensive screening (>10,000 nuclei) seems to be a useful tool to unequivocally identify micrometastatic cells by demonstrating hyperdiploidy and intranuclear chromosomal heterogeneity.
Combined intravenous and intraperitoneal chemotherapy with fluorouracil + leucovorin vs fluorouracil + levamisole for adjuvant therapy of resected colon carcinoma.
Scheithauer W. Kornek GV. Marczell A. Karner J. Salem G. Greiner R. Burger D. Stoger F. Ritschel J. Kovats E. Vischer HM. Schneeweiss B. Depisch D.
Department of Internal Medicine I, University of Vienna, Austria.
Adjuvant chemotherapy with fluorouracil (FU) and levamisole or FU/leucovorin (LV) has been established as effective adjuvant treatment for patients with stage III colon cancer. Among several other promising treatment strategies in resected colon cancer, intraperitoneal anti-cancer drug administration with its appealing rationale of counteracting microscopic residual disease on peritoneal surfaces and occult metachronous liver metastases by achieving high intraportal drug concentrations has not yet undergone sufficient clinical evaluation. To determine whether a combination of this locoregional therapeutic concept with systemic intravenous administration of FU/LV would yield better results than conventional adjuvant chemoimmunotherapy with FU/levamisole, the present randomized study was initiated. A total of 241 patients with resected stage III or high-risk stage II (T4N0M0) colon cancer were randomly assigned to 'standard therapy' with FU and levamisole, given for a duration of 6 months, or to an investigational arm, consisting of LV 200 mg m(-2) plus FU 350 mg m(-2), both administered intravenously (days 1-4) and intraperitoneally (days 1 and 3) every 4 weeks for a total of six courses. In patients with stage II disease, no significant difference was noted between the two arms after a median follow-up time of 4 years (range 2.5-6 years). Among 196 eligible patients with stage III disease, however, a comparative analysis of the two treatment groups suggested both an improvement in disease-free survival (P = 0.0014) and a survival advantage (P = 0.0005), with an estimated 43% reduction in mortality rate (95% confidence interval 26-70%) in favour of the investigational arm. In agreement with its theoretical rationale, combined intraperitoneal and intravenous FU/LV was particularly effective in reducing locoregional tumour recurrences with or without liver or other organ site involvement (9 vs 25 patients in the FU/levamisole arm; P = 0.005). Treatment-associated side-effects were infrequent and generally mild in both arms, although a lower rate of severe (WHO grade 3) adverse reactions was noted in patients receiving locoregional plus intravenous chemotherapy (3% vs 12%; P = 0.01). The results of this trial suggest that combined intraperitoneal plus systemic intravenous chemotherapy with FU/LV is a promising adjuvant treatment strategy in patients with surgically resected stage III colon carcinoma.
Multidisciplinary case teams: an approach to the future management of advanced colorectal cancer.
The Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
The effective management of advanced colorectal cancer has traditionally been viewed in terms of treatment outcome measures such as efficacy (survival, objective response and palliation) and safety. Although these outcomes are of paramount importance and are essential for the evaluation of the effectiveness and tolerability of treatment, they do not take account of the global effect of therapy on patients, society and healthcare systems. Furthermore, they may not reveal important differences between treatments of equivalent anti-tumour efficacy that might influence the overall effectiveness in terms of acceptability of therapy. To achieve this, a broader, patient-centred evaluation of advanced cancer treatment is required that acknowledges the views, experience and perspectives of all involved in the treatment process. To this end, the International Working Group in Colorectal Cancer, a multidisciplinary group that encompasses expertise from a range of relevant fields and disciplines, has advocated a multidisciplinary approach to the treatment of advanced colorectal cancer that is likely to deliver the best possible overall care.
Assessing patients needs and preferences in the management of advanced colorectal cancer.
University College Dublin, Republic of Ireland.
Clinical decision-making in advanced cancer is a highly complex process. Many factors are thought to influence this process arguably the most important of these is the patient's own preference. Studies show that most patients want to be fully informed as to their diagnosis and involved in clinical decision-making. However, the attitudes of healthcare workers often preclude patient involvement. Studies have also shown that acceptability of chemotherapy for minimal therapeutic gain differs markedly between patients depending on factors such as age, gender and family status. It is clearly impossible to make decisions about what is best for patients without involving them in the decision-making process. Indeed, it could be argued that active patient participation actually simplifies this process.
Measuring quality of life: impact of chemotherapy for advanced colorectal cancer. Experience from two recent large phase III trials.
Anderson H. Palmer MK.
Christie Hospital, Withington, Manchester, UK.
When assessing the value of a particular treatment, it is important to consider the impact it may have on the quality of life of those being treated. This is particularly so for cancer patients, whose life expectancy may be short. Patients with advanced colorectal cancer who participated in two international comparative studies of raltitrexed ('Tomudex') vs standard 5-fluorouracil (5-FU) plus leucovorin (LV) completed previously validated quality-of-life questionnaires (EORTC questionnaire, EuroQol and Rotterdam Symptom Check List) at various times during the studies. Early statistically significant advantages of raltitrexed vs 5-FU plus LV on quality of life were observed at week 2 in five of eight of the EuroQol and three of four of the Rotterdam Symptom Check List dimensions. Such advantages were not observed using the EORTC questionnaire, which was not completed until week 12. The necessary dose delays and different dose schedules made it difficult in these studies to compare the impact on quality of life of the two treatments. It may be that performance status, effect on disease-related symptoms and the incidence of toxicity are the most important indications of a patient's quality of life.
Mature results from three large controlled studies with raltitrexed (Tomudex).
The Royal Marsden Hospital, Sutton, UK.
Since the publication of the results of phase I dose-finding studies, an extensive phase II and III clinical study programme has been undertaken to study the clinical efficacy and tolerability of the quinazoline folate analogue raltitrexed ('Tomudex'), a novel direct and specific inhibitor of thymidylate synthase. Two international phase III trials, studies 3 and 12, have compared raltitrexed 3 mg m(-2) with 5-fluorouracil (5-FU) plus low-dose leucovorin (LV) (Mayo regimen) or high-dose LV (Machover regimen) respectively. A North American study (study 10) was originally set up to compare two raltitrexed dosage arms (3.0 and 4.0 mg m[-2]) with 5-FU and low-dose LV, but the 4.0 mg m(-2) arm was discontinued prematurely because of excessive toxicity. Minimum follow-up times for studies 3, 10 and 12 were 15.5, 12 and 9 months, respectively (for data other than survival), with corresponding survival follow-up times of 26, 12 and 17 months. Objective response rates were similar for raltitrexed and 5-FU + LV, and palliative improvements were seen to a similar extent with both treatments in all phase III studies. Survival was statistically similar for raltitrexed and 5-FU + LV in both studies 3 and 12. Raltitrexed was, however, associated with inferior survival to 5-FU + low-dose LV in study 10, but there appears to be evidence that this was linked to an unconscious effect on investigator behaviour of early toxicity problems in this trial, in that patients appeared to be withdrawn from raltitrexed treatment without progression or protocolled toxicity. Moreover, it appeared that 5-FU + LV patients were continued on treatment after disease progression. 5-FU-based therapy was associated with a higher incidence of mucositis than raltitrexed in all studies, with the attainment of statistical significance in studies 3 and 12. Elevations in hepatic transaminase levels were seen with raltitrexed, but these are thought to be of no clinical significance. Overall, much greater levels of toxicity were seen with 5-FU + LV than with raltitrexed in early treatment cycles. In addition, retrospective UK audit data have shown the monthly cost of raltitrexed therapy to be similar to that of Mayo and continuous infusion 5-FU regimens, and appreciably lower than that of the de Gramont regimen of 5-FU (bolus + 22-h infusion) + high-dose LV. Thus, raltitrexed is an effective alternative to 5-FU-based therapy in patients with advanced colorectal cancer, with an acceptable and, unlike 5-FU, predictable toxicity profile. In particular, patients receiving raltitrexed may benefit from the minimization or avoidance of mucositis, and both patients and healthcare providers may find the convenient administration schedule of the drug advantageous.
The establishment of a large collaborative trial programme in the adjuvant treatment of colon cancer.
The Laurentius Hospital, Roermond, The Netherlands.
After many years, during which the assumption prevailed that adjuvant chemotherapy was of no benefit in patients with resectable adenocarcinoma of the colon, findings of several large USA studies published from the late 1980s have caused a marked shift in surgical and medical opinion. Although results in patients with Dukes' B disease have not shown any clear benefit, the efficacy of adjuvant chemotherapy has nevertheless been shown in those with Dukes' C colon cancer. As a result, the Mayo regimen of 5-fluorouracil (5-FU) with low-dose leucovorin (LV) has become accepted as standard adjuvant therapy in these patients. However, the disadvantages associated with standard 5-FU-based treatment, particularly those relating to its toxicity and inconvenience of administration, have generated interest in other regimens and agents. The novel direct and specific thymidylate synthase inhibitor raltitrexed ('Tomudex') has been associated with similar objective response rates to standard therapy with 5-FU plus LV in patients with advanced colorectal cancer. In addition, raltitrexed has an attractive tolerability profile compared with that of 5-FU plus LV (specifically with respect to lower incidences of mucositis and leucopenia), and the simple 3-weekly administration schedule may be considered more convenient by many patients and may reduce healthcare resource consumption. To investigate alternatives to the Mayo regimen in the adjuvant treatment of Dukes' C adenocarcinoma of the colon, two large European trials have been set up: (1) PETACC-1 (first Pan-European Trial for Adjuvant Treatment of Colon Cancer), to compare raltitrexed with the Mayo regimen of 5-FU and low-dose LV; (2) PETACC-2 (second Pan-European Trial), to compare the Mayo regimen with three regimens in which 5-FU is given by prolonged infusion. These trials will provide valuable international data to add to those from the USA and will assess the place of raltitrexed in the adjuvant treatment of Dukes' C colon cancer. They will also compare directly for the first time infusional and bolus 5-FU regimens in the adjuvant setting.
New developments in cancer treatment with the novel thymidylate synthase inhibitor raltitrexed (Tomudex).
The Clinical Research Group (Oncology), Zeneca Pharmaceuticals, Macclesfield, Cheshire, UK.
Following the demonstration of efficacy, tolerability and quality-of-life benefits of raltitrexed ('Tomudex'), principally in advanced colorectal but also in other cancers, an extensive evaluation of combination therapy with other agents in patients with colorectal and other tumour types is being undertaken. This work has been prompted by preclinical observations of enhanced activity of raltitrexed when coadministered with other cytotoxic agents or radiotherapy and by preliminary results showing the activity of raltitrexed in patients with cancers other than colorectal. Raltitrexed is currently being investigated as monotherapy in phase I and II cancer studies, including head and neck cancer, hormone-resistant prostate cancer, paediatric and adult leukaemias and solid tumours, and soft tissue sarcoma. In addition, phase I clinical trials are evaluating the drug in combination with taxanes (paclitaxel) in solid tumours, anthracyclines (doxorubicin) in gastric carcinoma, topoisomerase I inhibitors (CPT-11) and 5-fluorouracil (both infusion and bolus regimens) in advanced colorectal cancer, platinum compounds (oxaliplatin and cisplatin) in a variety of tumours and radiotherapy in rectal cancer. Preliminary reports indicate good tolerability and acceptability of the combinations being investigated, with no dose-limiting toxicity being reported to date, and some early indications of efficacy.