title: Breast cancer resistance protein impacts clinical outcome in platinum-based chemotherapy for advanced non-small cell lung cancer.
abstract: OBJECTIVE
  The purpose of this study was to investigate the relationship between the level of expression of ATP-binding cassette (ABC) transporter proteins, and response to chemotherapy and prognosis in advanced non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Expression of ABC transporter proteins, including P-glycoprotein, multidrug resistance protein (MRP) 1, MRP2, MRP3, and breast cancer resistance protein (BCRP), was examined immunohistochemically in 72 formalin-fixed tumor samples from untreated stage IIIB or IV NSCLC patients. All of the patients received platinum-based chemotherapy. Response to chemotherapy, progression-free survival (PFS), and overall survival were compared in relation to expression of each of the ABC transporter proteins and clinicopathological factors.
  
  
  RESULTS
  Expression of P-glycoprotein, MRP1, and MRP3 was not significantly associated with response to chemotherapy or survival. MRP2 expression was associated with overall survival (P = 0.002) but not with response to chemotherapy and PFS. By contrast, the response rate to chemotherapy of patients with BCRP-negative tumors was 44%, as opposed to 24% in patients with BCRP-positive tumors. Response rate was lower in BCRP-positive tumors, although this difference was not statistically significant (P = 0.08). BCRP-positive patients had also shorter PFS (P = 0.0003) and overall survival (P = 0.004) than BCRP-negative patients. Multivariate analysis confirmed BCRP status as an independent variable related to PFS (P = 0.001).
  
  
  CONCLUSIONS
  Positive immunostaining for BCRP appears to be a predictor of survival in patients with advanced NSCLC. These findings indicate that BCRP may serve as a molecular target for reducing drug resistance to chemotherapy in advanced NSCLC patients.
authors.affiliation: Pathology Division, National Cancer Center Research Institute East, Chiba, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Yoh
authors.forename: Genichiro
authors.initials: G
authors.lastname: Ishii
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yokose
authors.forename: Yuji
authors.initials: Y
authors.lastname: Minegishi
authors.forename: Kohji
authors.initials: K
authors.lastname: Tsuta
authors.forename: Koichi
authors.initials: K
authors.lastname: Goto
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nishiwaki
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Kodama
authors.forename: Moritaka
authors.initials: M
authors.lastname: Suga
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000032:analysis*; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000473:pathology; D002945:Cisplatin / Q000627:therapeutic use*; D018432:Drug Resistance, Multiple / Q000235:genetics; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D011379:Prognosis; D016896:Treatment Outcome
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D002945:Cisplatin