title: The association between chemosensitivity and Pgp, GST-π and Topo II expression in gastric cancer.
abstract: BACKGROUND
  To investigate the relationship between P-glycoprotein (Pgp), glutathione S-transferase π (GST-π) and topoisomerase II (Topo II) expression and human gastric cancer chemoresistance in vitro.
  
  
  METHODS
  Primary single-cell suspensions were prepared from fresh specimens of primary gastric cancer and exposed to hydroxycamptothecin (HCPT), cisplatin (CDDP), 5-fluorouracil (5-FU), adriamycin (ADM) and mitomycin (MMC) for 48 h. Cell metabolic activity and rate of inhibition were evaluated using tetrazolium (MTT) assay. Pgp, GST-π and Topo II expression was determined in gastric carcinoma tissue samples using immunohistochemistry.
  
  
  RESULTS
  Chemosensitivity of the gastric cancer cells varied; the rates of inhibition of cells exposed to HCPT, CDDP and 5-FU were significantly higher than that of cells exposed to ADM and MMC (p < 0.05). Gastric cancer cells with Pgp expression were resistant to ADM and HCPT (p = 0.008 and p = 0.011, respectively). Cells resistant to 5-FU, CDDP and MMC had significantly higher GST-π expression (p < 0.05). Topo II expression was significantly lower in cells resistant to HCPT, ADM and MMC (p < 0.05). Pgp and GST-π expression may contribute to primary resistance of gastric cancer cells to some chemotherapeutic drugs, while Topo II expression may indicate HCPT, ADM and MMC sensitivity.
  
  
  CONCLUSIONS
  Pgp, GST-π and Topo II detection and the MTT assay could be used as predictors in chemotherapeutic drug administration and for identifying drug resistance in gastric carcinoma.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3448329111142964.
authors: Ming
authors: M
authors: Geng
authors: Lin
authors: L
authors: Wang
authors: Xin
authors: X
authors: Chen
authors: Ruixue
authors: R
authors: Cao
authors: Department of Pathology, General Hospital of Jinan Military Command, Jinan, China. lipeifeng00@hotmail.com.
authors: Peifeng
authors: P
authors: Li
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002166:Camptothecin / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D002478:Cells, Cultured; D002945:Cisplatin / Q000494:pharmacology / Q000627:therapeutic use; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004317:Doxorubicin / Q000494:pharmacology / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D005472:Fluorouracil / Q000494:pharmacology / Q000627:therapeutic use; D005753:Gastric Mucosa / Q000378:metabolism; D051549:Glutathione S-Transferase pi / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D016685:Mitomycin / Q000494:pharmacology / Q000627:therapeutic use; D013270:Stomach / Q000187:drug effects / Q000473:pathology; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D016685:Mitomycin; D004317:Doxorubicin; C120029:homocamptothecin; D051549:Glutathione S-Transferase pi; D004250:DNA Topoisomerases, Type II; D002945:Cisplatin; D005472:Fluorouracil; D002166:Camptothecin