Silencing of integrin-linked kinase suppresses in vivo tumorigenesis of human ovarian carcinoma cells.

Integrin-linked kinase (ILK) plays a role in the regulation of multiple cellular functions (e.g., promoting cell migration and proliferation, but inhibiting cell adhesion). This study investigated the inhibitory effects of ILK gene knockdown on the regulation of in vivo tumorigenesis of human ovarian carcinoma cells in nude mouse xenografts. HO-8910 cells were transfected with an ILK antisense oligonucleotide (ILK-ASO) to silence the ILK gene. Expression of ILK mRNA and protein was evaluated by RT-PCR and western blotting, respectively. The cell cycle was assessed by flow cytometric analysis. Cells with or without ILK-ASO transfection were subcutaneously injected into nude mice. The mouse body weight, tumor formation, tumor size and tumor weight were determined up to 30 days after inoculation. Tumor cells transfected with ILK-ASO had significantly decreased ILK mRNA and protein expression (P<0.01) when compared to the control cells. ILK gene silencing significantly increased the number of cells in the G0/G1 phase (67.61 vs. 43.29%, χ2=1197.15, P<0.01). After tumor cell inoculation, tumor cells transfected with ILK-ASO showed significantly delayed tumor formation when compared to control (9.10±0.74 vs. 5.30±0.67 days, respectively; P<0.01). In addition, tumor growth was suppressed in the 30 days following inoculation (P<0.01 compared with the controls). The average tumor weight in the ILK-ASO group was statistically lower than that of the control group (1.29±0.11 vs. 1.57±0.13 g, respectively; P<0.01). This study demonstrated that ILK-ASO transfection efficiently downregulated ILK expression in human ovarian carcinoma HO-8910 cells and that ILK gene silencing suppressed tumor growth in nude mice xenografts.