title: The expression and significance of MRP1, LRP, TOPOIIβ, and BCL2 in tongue squamous cell carcinoma.
abstract: BACKGROUND
  Multiple drug resistance protein 1 (MRP1), lung resistance protein (LRP), topoisomerase IIβ (TOPOIIβ) and B-cell lymphoma 2 (BCL2) are well known in the development of drug resistance in cancer cells. The aim of this study was to evaluate the relationship between them and the clinicopathological features, their expression differences between tumor tissue and experimental drug-resistant model in tongue carcinoma.
  
  
  METHODS
  Multiple drug resistance protein 1, LRP, TOPOIIβ, and BCL2 expression was examined by immunohistochemistry in specimens from radical surgeries of 65 patients with tongue carcinoma. A cisplatin-resistance cell line, SCC-15/cisplatin, was established from a cisplatin-sensitive cell line, SCC-15. A MTT-based method was used to analyze drug potencies. Immunofluorescence was used to detect protein expression in both cell lines. Western blot was used to compare the protein expressions in specimens and SCC-15/cisplatin cells.
  
  
  RESULTS
  We found higher expression of MRP1, LRP, and BCL2 and lower expression of TOPOIIβ in tongue carcinoma compared with adjacent non-neoplastic tongue tissues (P < 0.05). In addition, MRP1 and TopoIIβ expression were significantly associated with clinical stage, lymph node metastasis and histologic grade, and LRP was significantly associated with histologic grade in the samples (P < 0.05). Finally, Western blot showed that higher expressions of MRP1, LRP, and BCL2 and lower expression of TopoIIβ were observed in SCC-15/cisplatin cells than in clinical samples.
  
  
  CONCLUSIONS
  Our results suggest that the high expressions of MRP1, LRP, and BCL2 and low expression of TOPOIIβ in patients with tongue carcinoma indicates that intrinsic drug resistance may exist in tongue carcinoma, and is associated with tumor differentiation and cisplatin resistance in tongue carcinoma.
authors.affiliation: Department of Oral and Maxillfacial Surgery, Guanghua College of Stomatology, Institute of Stomatological Research, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Mo
authors.initials: M
authors.lastname: Liu
authors.forename: Hai-kuo
authors.initials: HK
authors.lastname: Tang
authors.forename: Hui-bin
authors.initials: HB
authors.lastname: Ma
authors.forename: Cheng
authors.initials: C
authors.lastname: Wang
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Chen
authors.forename: Hong-zhang
authors.initials: HZ
authors.lastname: Huang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000556:secondary; D045744:Cell Line, Tumor; D048430:Cell Shape; D002945:Cisplatin / Q000494:pharmacology; D004396:Coloring Agents; D004250:DNA Topoisomerases, Type II / Q000032:analysis*; D004268:DNA-Binding Proteins / Q000032:analysis*; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000032:analysis*; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D013778:Tetrazolium Salts; D013844:Thiazoles; D014059:Tongue / Q000473:pathology; D014062:Tongue Neoplasms / Q000473:pathology*; D020394:Vault Ribonucleoprotein Particles / Q000032:analysis*; D000099187:Major Vault Protein
chemical_list: D000970:Antineoplastic Agents; D002945:Cisplatin; D004396:Coloring Agents; D004250:DNA Topoisomerases, Type II; D004268:DNA-Binding Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D013778:Tetrazolium Salts; D013844:Thiazoles; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein; C022616:thiazolyl blue; C421109:multidrug resistance-associated protein 1