Insulin/PI3K signalling pathway regulates the expression of survivin in liver cancer HepG2 cells / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To determine the expression level changes of survivin, a inhibitor of apoptosis protein, followed by activation of insulin receptors in human hepatocellular carcinoma HepG2 cell line, and to investigate the signalling pathway involved in the regulation.</p><p><b>METHODS</b>Human hepatocellular carcinoma HepG2 cells were treated with insulin alone or pre-treated with LY294002, a specific inhibitor of PI3K signalling pathway, to determine whether blocking PI3K signaling can attenuate the up-regulation of survivin expression. Real time RT-PCR and Western blot analysis were used to measure survivin mRNA and protein changes before and after treatment, respectively.</p><p><b>RESULTS</b>Without serum supplement, HepG2 cells expressed a small amount of survivin. Insulin induced survivin expression in a dose- and time-dependent fashion. Survivin expression was blocked if cells were pre-treated with LY294002 prior to insulin stimulation.</p><p><b>CONCLUSION</b>Insulin induces survivin expression via PI3K signalling pathway, suggesting that to interfere the key gene in this signalling pathway may block survivin expression, therefore, promoting apoptosis in hepatocellular carcinoma cells.</p>