Expression of H type 1 antigen of ABO histo-blood group in normal colon and aberrant expressions of H type 2 and H type 3/4 antigens in colon cancer

We have immunohistochemically examined the distribution of the H antigens o f type 1, type 2 and type 3/4 chains of the ABO(H) histo-blood group system in human normal colon and in colon cancer using three monoclonal antibodie s specific for each of the H type 1/2, H type 2, and the H type 3/4 chain. We unexpectedly found that mucosa of the normal colon from secretors but no t that from nonsecretors expressed only H type 1 and did not express H type 2 or H type 3/4. The H type 1 was expressed in goblet cells. Positive gobl et cells expressing H type 1 were decreased in number progressively from th e proximal colon to the rectum. In tumors, 4 (57%) of 7 cancer tissues of t he proximal colon from secretors expressed no H type 1, whereas all 8 cance r tissues of the distal colon from secretors expressed H type 1. The aberra nt expressions of H type 2 and H type 3/4 (47 and 67%, respectively) were f ound in cancer tissues from both the proximal and the distal colon. Tumors from nonsecretors did not express any H antigens. Our results suggested tha t the expression of H type 1 in the normal colon and the aberrant expressio ns of H type 2 and H type 3/4 in colon cancer tissues were regulated by FUT 2-encoded Se type alpha (1,2)fucosyltransferase. However, UEA-I-positive su bstance(s) rather than H type 2 were uniquely expressed throughout the norm al colon and in colon cancers from both secretors and nonsecretors.