title: Transcriptional suppression of breast cancer resistance protein (BCRP) by wild-type p53 through the NF-kappaB pathway in MCF-7 cells.
abstract: Breast cancer resistance protein (BCRP) has been shown to confer multidrug resistance, but the mechanisms of its regulation are poorly understood. Here, we investigate the effects of wild-type and mutant p53, and nuclear factor kappa-B (NF-kappaB) (p50) on BCRP promoter activity in MCF-7 cells. Our results demonstrated that wild-type p53 markedly suppressed BCRP activity and enhanced the chemosensitivity of cells to mitoxantrone, whereas mutant p53 had little inhibitory effect. After inhibition of NF-kappaB, similar results were obtained. Following knockdown of endogenous p53, BCRP and p50 expressions were increased, and the chemosensitivity of the cells to mitoxantrone was decreased. We conclude that wild-type p53 acts as a negative regulator of BCRP gene transcription.
authors.affiliation: Cancer Research Institute, Xiangya Medical School, Central South University, Changsha, China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Wang
authors.forename: Xingang
authors.initials: X
authors.lastname: Wu
authors.forename: Chengkun
authors.initials: C
authors.lastname: Wang
authors.forename: Weijia
authors.initials: W
authors.lastname: Zhang
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Ouyang
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Yu
authors.forename: Zhimin
authors.initials: Z
authors.lastname: He
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000378:metabolism; D001665:Binding Sites; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D050505:Mutant Proteins / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D015398:Signal Transduction; D013489:Suppression, Genetic; D051996:Transcription Factor RelA / Q000378:metabolism; D014158:Transcription, Genetic; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D020672:I-kappa B Proteins; D050505:Mutant Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D009363:Neoplasm Proteins; D051996:Transcription Factor RelA; D016159:Tumor Suppressor Protein p53; D000072000:NF-KappaB Inhibitor alpha