title: Mechanistic analysis of taxol-induced multidrug resistance in an ovarian cancer cell line.
abstract: OBJECTIVE
  To establish a taxol-resistant cell line of human ovarian carcinoma (A2780/Taxol) and investigate its biological features.
  
  
  METHODS
  The drug-resistant cell line (A2780/Taxol) was established by continuous stepwise selection with increasing concentrations of Taxol. Cell morphology was assessed by microscopy and growth curves were generated with in vitro and in vivo tumor xenograft models. With rhodamine123 (Rh123) assays, cell cycle distribution and the apoptotic rate were analyzed by flow cytometry (FCM). Drug resistance-related and signal associated proteins, including P-gp, MRPs, caveolin-1, PKC-α, Akt, ERK1/2, were detected by Western blotting.
  
  
  RESULTS
  A2780/Taxol cells were established with stable resistance to taxol. The drug resistance index (RI) was 430.7. Cross-resistance to other drugs was also shown, but there was no significant change to radioresistance. Compared with parental cells, A2780/Taxol cells were significantly heteromorphous, with a significant delay in population doubling time and reduced uptake of Rh123 (p < 0.01). In vivo, tumor take by A2780 cells was 80%, and tumor volume increased gradually. In contrast, with A2780/Taxol cells in xenograft models there was no tumor development. FCM analysis revealed that A2780/Taxol cells had a higher percentage of G0/G1 and lower S phase, but no changes of G2 phase and the apoptosis rate. Expression of P-gp, MRP1, MRP2, BCRP, LRP, caveolin-1, PKC-α, Phospho-ERK1/2 and Phospho-JNK protein was significantly up-regulated, while Akt and p38 MARK protein expression was not changed in A2780/Taxol cells.
  
  
  CONCLUSIONS
  The A2780/Taxol cell line is an ideal model to investigate the mechanism of muti-drug resistance related to overexpression of drug-resistance associated proteins and activation of the PKC-α/ERK (JNK) signaling pathway.
authors.affiliation: Department of Gynecological Oncology Surgery, Jiangsu Cancer Hospital and Institute, Nanjing Medical University, Nanjing, Jiangsu, China E-mail : wangjinhua588@163.com.
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Wang
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhao
authors.forename: Li-Nan
authors.initials: LN
authors.lastname: Wu
authors.forename: Ming-Feng
authors.initials: MF
authors.lastname: He
authors.forename: Jun-Wei
authors.initials: JW
authors.lastname: Qu
authors.forename: Yi-Bing
authors.initials: YB
authors.lastname: Zhao
authors.forename: Wan-Zhou
authors.initials: WZ
authors.lastname: Zhao
authors.forename: Jie-Shou
authors.initials: JS
authors.lastname: Li
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Wang
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000187:drug effects / Q000378:metabolism; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002277:Carcinoma / Q000235:genetics* / Q000378:metabolism; D051242:Caveolin 1 / Q000187:drug effects / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D018432:Drug Resistance, Multiple / Q000235:genetics* / Q000502:physiology; D019008:Drug Resistance, Neoplasm / Q000235:genetics* / Q000502:physiology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000187:drug effects / Q000378:metabolism; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000187:drug effects / Q000378:metabolism; D009363:Neoplasm Proteins / Q000187:drug effects / Q000378:metabolism; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism; D017239:Paclitaxel / Q000494:pharmacology*; D051571:Protein Kinase C-alpha / Q000187:drug effects / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000187:drug effects / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D000972:Antineoplastic Agents, Phytogenic; D051242:Caveolin 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009363:Neoplasm Proteins; D017239:Paclitaxel; D051571:Protein Kinase C-alpha; D051057:Proto-Oncogene Proteins c-akt; C000715087:ABCC2 protein, human; C116614:ABCG2 protein, human; C535150:MAPK1 protein, human; C421109:multidrug resistance-associated protein 1