SHIP2 sensitizes gastric cancer cells BGC-823 to paclitaxel through upregulation of Bim / 中国药理学通报

ABSTRACT

Aim To study the sensitivity of human gastric cancer BGC-823 cells to paclitaxel after trans-fection of SHIP2 ( The SH2 domain containing inositol 5-phosphatase 2 ) cDNA. Methods Apoptotic cells were determined by the propidium iodide method using flow cytometry. The levels of protein and mRNA ex-pression were measured by Western blot analysis and qRT-PCR, respectively. pCMV6-SHIP2 plasmid and empty vector were transiently transfected into BGC-823 cells, respectively. Stable cell lines were established after infecting BGC-823 cell with GV112-Puromycin and GV112-Puromycin-Bim( Bcl-2 interacting mediator of cell death) lentivirus particles. pCMV6-SHIP2 plas-mid was transiently transfected into the stable cell lines. Results BGC-823 cells were relatively insensi-tive to paclitaxel compared with SGC-7901 cells. The apoptotic rate was only (25. 6 ± 1. 6)% after the treat-ment with 0 . 3 μmol · L-1 paclitaxel for 48 h in BGC-823 cells. The expression levels of Bim protein and mRNA in BGC-823 cells treated with paclitaxel at dif-ferent time points were not significantly changed. The expression of Bim protein was increased after transfec-tion of pCMV6-SHIP2 plasmid, and the apoptotic rate was up to ( 50. 8 ± 0 . 9 )% in BGC-823 cells treated with paclitaxel for 48h. The expression of Bim protein was significantly inhibited after infecting with GV112-Puromycin-Bim lentivirus particles. The apoptotic rate of infected BGC-823 cells was only ( 27. 6 ± 1. 6 )%after treatment upon paclitaxel for 48h. Conclusion Overexpression of exogenous SHIP2 can increase the expression of Bim, induce apoptosis and enhance sen-sitivity of BGC-823 cells to paclitaxel.