title: Establishment and characterization of multidrug-resistant gastric cancer cell lines.
abstract: OBJECTIVE
  The aim of this study was to establish drug-resistant cell lines and to elucidate mechanisms leading to multi-drug resistance in gastric cancer.
  
  
  METHODS
  Five cancer cell lines resistant to 5-fluorouracil, paclitaxel, oxaliplatin, irinotecan, or gemcitabine, were respectively established from a parent gastric cancer cell line, OCUM-2M, by stepwise exposure to each chemotherapeutical agent.
  
  
  RESULTS
  Cell death by apoptosis induced by anti-cancer drugs was low in 5 chemo-resistant cell lines. Percentage of cells in S and G(0)/G(1) phase was low in cell lines resistant to oxaliplatin or irinotecan. Cell lines resistant to paclitaxel, oxaliplatin, and gemcitabine showed multi-drug resistance. Alterations in MRP, DAPK1, or DAPK2 expression were found in multi-drug resistant cell lines.
  
  
  CONCLUSIONS
  The cell-cycle distribution and alterations of MRP, DAPK1, and DAPK2 genes may be integral part of mechanisms responsible for chemo-resistance. These cell lines might be useful to study molecular mechanisms leading to multi-drug resistance.
authors.affiliation: Department of Surgical Oncology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Xiaotian
authors.initials: X
authors.lastname: Zhang
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yashiro
authors.forename: Hong
authors.initials: H
authors.lastname: Qiu
authors.forename: Takafumi
authors.initials: T
authors.lastname: Nishii
authors.forename: Taro
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Kosei
authors.initials: K
authors.lastname: Hirakawa
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000096:biosynthesis; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000096:biosynthesis; D002166:Camptothecin / Q000031:analogs & derivatives / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D064550:Death-Associated Protein Kinases; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D006801:Humans; D000077146:Irinotecan; D009944:Organoplatinum Compounds / Q000494:pharmacology; D000077150:Oxaliplatin; D017239:Paclitaxel / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000093542:Gemcitabine
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000972:Antineoplastic Agents, Phytogenic; D051017:Apoptosis Regulatory Proteins; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D003841:Deoxycytidine; D000077146:Irinotecan; C579096:DAPK1 protein, human; C579104:DAPK2 protein, human; D064550:Death-Associated Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D017239:Paclitaxel; D002166:Camptothecin; D000093542:Gemcitabine