Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C1864663 (HCC)
 2,985 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Resistance modifying agents (RMA) such as verapamil (VER) have proved effective in reversing multidrug resistance (MDR) in many in vitro experimental models, but clinical results with RMA have been disappointing. To clarify this apparent discrepancy we have evaluated the cytotoxic effects of doxorubicin (DOX) plus VER in four human colon carcinoma (HCOC) cell lines (LoVo, DLD-1, SW948, SW1116). These lines were selected on the basis of their levels of mdr1 mRNA being similar to those expressed by HCC obtained from non-drug-treated patients. In all cell lines the sensitising effect of VER on DOX cytotoxicity was schedule-dependent and maximal potentiation of DOX cytotoxicity was obtained by exposure to VER for a time > or = the cells' population doubling time.
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PMID:Increased chemosensitivity to doxorubicin of intrinsically multidrug-resistant human colon carcinoma cells by prolonged exposure to verapamil. 839 9

The level of sulfo-Lea (SO3-3Gal beta 1-3(Fuc alpha 1-4)GlcNAc) epitope recognized by monoclonal antibody (mAb) 91.9H in hepatic metastasis of colon carcinoma is known to be lower than at the primary sites. We examined 19 human colon carcinoma cell lines for their production of this epitope. Sixteen cell lines were found to produce high M(r) components that metabolically incorporated [35S]sulfate and were resistant to heparitinase I and chondroitinase ABC, and 8 of them were reactive with mAb 91.9H as shown by western blotting analysis. These were all of the 4 cell lines derived from well differentiated primary tumors (HCCP-2998, LS174T, GEO, and CBS), 2 of 10 cell lines (DLD-1 and HCT116) from moderately to poorly differentiated primary tumors, and 2 of 5 cell lines (SW480 and HCC-M1544) from metastases. Incubation of LS174T cells with benzyl-N-acetyl-alpha-D-galactosaminide abrogated the incorporation of [35S]sulfate and the reactivity of mAb 91.9H with high M(r) components in the cell lysates. Sodium chlorate, which inhibits the formation of 3'-phosphoadenosine 5'-phosphosulfate, also inhibited the [35S]sulfate incorporation and reactivity with mAb 91.9H. These treatments did not change the incorporation of [14C]threonine into high M(r) components. These results indicated that sulfo-Lea epitopes were expressed on O-linked carbohydrate chains in sulfomucins. Immunohistochemical studies of tumor tissues in nude mice indicated that sulfo-Lea was expressed at the site of orthotopic transplantation in the cecum. The expression appeared to be suppressed in liver metastatic foci in nude mice.
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PMID:Expression of mucin-associated sulfo-Lea carbohydrate epitopes on human colon carcinoma cells. 1008 87