The significance of anti-sialyl-Tn antibodies in patients with colorectal and breast cancer.
Coomber DW. Hawkins NJ. Dalley D. Ward RL.
Department of Medical Oncology, St Vincent's Hospital, Sydney, NSW, Australia.
The sera of 54 individuals with colorectal or breast cancer, and 50 healthy volunteers were assayed for the presence of anti-bovine submaxillary mucin antibodies using an enzyme linked immunoassay. The serum levels of these antibodies were found to be significantly lower in people with breast (p < 0.001) or colorectal cancer (p < 0.001) with respect to healthy individuals. Within the colorectal cancer group the presence of antibodies was significantly lower in those individuals with poorly differentiated tumors compared to other histological grades (p < 0.05), but did not correlate with the presence of local or distant metastases or anatomical location of the tumor (p > 0.05). No correlation was found with respect to the age of the patient and the level of anti-sialyl-Tn antibodies (p > 0.05). Competition analysis with the anti-sialyl-Tn monoclonal antibody 3C2 indicated that the activity against bovine submaxillary mucin was primarily due to specificity for the sialyl-Tn epitope of the glycoprotein. In contrast to findings with other tumor associated antigens, we could find no evidence of an increase in the level of antibodies against this epitope.