Impact of PI3K /Akt /mdm2 signaling pathway on the sensitivity of gastric cancer cell line SGC7901 to doxorubicin / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To explore whether PI3K/Akt/mdm2 signalling pathway affect the sensitivity of gastric cancer cell line SGC7901 cells to doxorubicin.</p><p><b>METHODS</b>Gastric cancer cell line SGC7901 cells were exposed to doxorubicin and specific PI3K inhibitor wortmannin. Cell apoptosis was detected using flow cytometry. PI3K activity was detected by radioactive immunoprecipitation-kinase assay. Western blotting was employed to evaluate the expressions of PI3K-p85, pAkt-S473, Akt, pmdm2-S166 and p53.</p><p><b>RESULTS</b>The level of apoptosis in gastric cancer SGC7901 cells treated with doxorubicin was gradually increasing. wortmannin enhanced its effects significantly. PI3K activity and the expression of pAkt-S473 increased in a time-dependent manner, pmdm2-S166, p53 were also increased wortmannin inhibited phosphorylation of mdm2 and improved the p53 expression.</p><p><b>CONCLUSION</b>PI3K/Akt/mdm2 signalling pathway can be activated by doxorubicin and suppress apoptosis by promoting phosphorylation of mdm2. PI3K inhibitor wortmannin can enhance sensitivity of gastric cancer cells to chemotherapy.</p>