Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sialyl Lewis a/sialyl Lewis x antigens, which panels of monoclonal antibodies can recognize, are synthesized by a series of glycosyltransferases. Especially, alpha (1,3)/(1,4) fucosyltransferases and/or alpha(2,3)sialyltransferases regulate expression patterns temporally and spatially, such as in epithelium of digestive systems or in leukocytes. The carbohydrate ligands of P-selectin and E-selectin have been identified as sialyl Lewis x expressed on granulocytes, monocytes, and natural killer cells. Expression of sialyl Lewis x on these cells is mainly determined by Fuc-TVII, but as for the counterparts of sialyl-transferases, there remains much uncertainty. P-selectin-dependent adhesion of tumor cells and E-selectin-dependent adhesion of tumor cells to endothelial cells play some role for tumor cell aggregation leading to microembolism and hematogenous metastasis of cancers. We have found expression of some fucosyltransferases (Fuc-TIII, VI, VII) and a sialyltransferase (ST3O) are increased in colon cancer tissues coincidentally with sialyl Lewis a antigens, with which E-selectin can interact. As already started in many laboratories, genetic manipulation of glycosylation pathways in gene-targeted animals has an outstanding potential to yield clues to oligosaccharide function.
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PMID:[Structures, synthesis and functions of sialyl Le(a)/sialyl Le(x) antigens]. 763 14

Recent studies have demonstrated that selectins, a new family of cell-adhesion molecules with similar domain structures, mediate the adhesion of peripheral blood cells to interleukin-1 (IL-1)-activated endothelium. In the present study the authors evaluated the role of E-selectin-Sialyl Lewis x (SLe(x))/ Sialyl Lewis a (SLe(a)) interaction in mediating in vitro adhesion of two colon cancer cell lines, HT-29 and COLO 201, to human umbilical cord endothelial cells (HUVEC). Colon cancer cell lines had a strong expression of blood group-related carbohydrate epitopes as evaluated by fluorescence-activated cell sorter (FACS) analysis. It was established that adhesion of HT-29 and COLO 201 cells to IL-1 stimulated HUVEC was calcium dependent and could be inhibited by a monoclonal antibody directed against E-selectin. Prior incubation of cells with two different antibodies directed against SLe(x) and antibodies directed against related Lewis epitopes, Le(x) and Le(a), had no significant effect on adhesion. Three antibodies directed against SLe(a) differed in their capacity to inhibit the adhesion of HT-29 and COLO 201 cells to HUVEC. Only one antibody directed against the SLe(a) structure was effective in inhibiting adhesion of both COLO 201 and HT-29 cells. The difference could not be attributed to titre, the type or number of glycoproteins, or to a difference in the amount of SLe(a) present on individual proteins, suggesting that presence and right presentation of SLe(a) epitope might be important for adhesion of colon cancer cells. Finally, in the in vitro system used, adhesion of HT-29 and COLO 201 cells to activated HUVEC is mediated predominantly by E-selectin/SLe(a) interaction. SLe(x) and related epitopes, Le(x) and Le(a), seem to have limited relevance for colon cancer cell recognition of E-selectin.
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PMID:E-selectin: sialyl Lewis, a dependent adhesion of colon cancer cells, is inhibited differently by antibodies against E-selectin ligands. 879 12