title: Overexpressed WAF1/Cip1 renders glioblastoma cells resistant to chemotherapy agents 1,3-bis(2-chloroethyl)-1-nitrosourea and cisplatin.
abstract: Previous studies have shown that the negative cell cycle regulator WAF1/Cip1 is often overexpressed in human gliomas and that WAF1/Cip1 overexpression may be a factor in cancer chemoresistance. We established a doxycycline-inducible WAF1/Cip1 expression system in two glioblastoma cell lines and examined the role of WAF1/Cip1 in their response to the chemotherapy agents 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and cis-diamminedichloroplatinum (cisplatin), in an isogeneic background. Our results showed that the induction of WAF1/Cip1 expression rendered glioma cells resistant to cell death induced by BCNU and cisplatin. Using an in vivo host-cell reactivation DNA repair assay, we demonstrated that WAF1/Cip1 enhances the repair of BCNU-induced DNA damage. We conclude that WAF1/Cip1 allows repair of BCNU- and cisplatin-damaged DNA and protects glioma cells from chemotherapy agent-induced apoptosis. Thus, blocking WAF1/Cip1 production or function may serve as a useful chemosensitization regimen for glioma.
authors.affiliation: Department of Neuro-Oncology, The University of Texas M. D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ruan
authors.forename: M F
authors.initials: MF
authors.lastname: Okcu
authors.forename: J P
authors.initials: JP
authors.lastname: Ren
authors.forename: P
authors.initials: P
authors.lastname: Chiao
authors.forename: M
authors.initials: M
authors.lastname: Andreeff
authors.forename: V
authors.initials: V
authors.lastname: Levin
authors.forename: W
authors.initials: W
authors.lastname: Zhang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D018906:Antineoplastic Agents, Alkylating / Q000494:pharmacology*; D002330:Carmustine / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002945:Cisplatin / Q000494:pharmacology*; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000096:biosynthesis* / Q000235:genetics; D004249:DNA Damage; D004260:DNA Repair; D004273:DNA, Neoplasm / Q000187:drug effects / Q000378:metabolism; D004317:Doxorubicin / Q000494:pharmacology; D004318:Doxycycline / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005909:Glioblastoma / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D018906:Antineoplastic Agents, Alkylating; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004273:DNA, Neoplasm; D004317:Doxorubicin; D004318:Doxycycline; D002945:Cisplatin; D002330:Carmustine