title: Expression of the P-glycoprotein gene in multidrug-resistant Chinese hamster ovary cells.
abstract: A series of multidrug-resistant (MDR) Chinese hamster ovary (CHO) cells was established to survive in stepwise increasing concentrations of vincristine. These MDR cells contained amplified P-glycoprotein (mdr) genes. Using monoclonal antibody against the P-glycoprotein, we present here results showing that the levels of P-glycoprotein and its phosphorylation and glycosylation did not correlate with those of drug resistance. Our results suggest that overproduction of the P-glycoprotein cannot account for the differences in drug resistance in these MDR cells, and that multiple modalities are involved in multiple drug resistance in mammalian cells.
authors.affiliation: Department of Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston 77030.
authors.forename: T
authors.initials: T
authors.lastname: Mukhopadhyay
authors.forename: M T
authors.initials: MT
authors.lastname: Kuo
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D004351:Drug Resistance; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D009369:Neoplasms / Q000188:drug therapy; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D008562:Membrane Glycoproteins; D012333:RNA, Messenger