Immunohistochemical examination of anti-STn monoclonal antibodies LLU9B4, B72.3, and B35.2 for their potential use as tumor markers.

Purpose: Several investigators, including ourselves, have demonstrated by immunohistochemistry that in malignancy of colon, the tumor cells or cells adjacent to the tumor become reactive with anti-STn monoclonal antibodies, while in normal individuals the colonic cells do not react with anti-STn monoclonal antibodies. In the present study, an anti-STn monoclonal antibody LLU9B4 was generated in the laboratory by immunization of mice with STn extracted from LS174T, along with commercially available B72.3 and B35.

Noninvasive colorectal cancer screening.

Abnormal mucin with the STn epitope is produced by colorectal cancer cells and is immunologically distinguishable from normal colonic mucin. Herein we describe a technique of detecting abnormal mucin in fecal samples as a method of screening for colorectal neoplasia. Soluble glycoproteins from fecal samples of patients with symptoms of bowel disease and asymptomatic volunteer subjects were isolated by centrifugation and ethanol precipitation.