Induction of Apoptosis by IGFBP3 Overexpression in Hepatocellular Carcinoma Cells

Background: The insulin-like growth factor (IGF) system comprises a group of proteins that play key rolesin regulating cell growth, differentiation, and apoptosis in a variety of cellular systems. The aim of this studywas to investigate the role of insulin-like growth factor binding protein 3 (IGFBP3) in hepatocellular carcinoma.Materials and
Methods: Expression of IGF2, IGFBP3, and PTEN was analyzed by qRT-PCR. Lentivirus vectorswere used to overexpress IGFBP3 in hepatocellular carcinoma cell (HCC) lines. The effect of IGFBP3 onproliferation was investigated by MTT and colony formation assays.
Results: Expression of IGF2, IGFBP3, andPTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2’-deoxycytidine/trichostatin Atreatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpressionof IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells.
Conclusions: Expression of IGF2,IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2’-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCCcells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells.