Objective: To study the inhibitory effects of antisense focal adhesion kinase (FAK) oligodeoxynucleotides (ODN) on the invasion of Bel 7402 cells, and investigate the mechanisms.
Methods: LipofecTAMINE-mediated antisense FAK ODN was transfected into Bel 7402 cells. Cell number and viability were evaluated every 24 hours by trypan blue dye exclusion. Cell attachment assay was carried out at intended time points in a microculture well pre-coated with fibronectin (FN). The invasive activity of tumor cells was assayed in a transwell cell culture chamber. Cell cycle and cell apoptosis analysis were performed with flow cytometry (FCM).
Results: The expression of p125FAK in the group treated with antisense FAK ODN (6.49%+/-0.10%) significantly decreased, compared with those in the group treated with sense FAK ODN (14.33%+/-1.88%) and control group (16.68%+/-1.62%), F=7.66, P<0.01. Antisense FAK ODN significantly inhibited the growth of Bel 7402 cells by 30%-60%, the attachment by 25%-55%, and the invasion, 15%-25%. The decreased expression of FAK in Bel 7402 cells caused a G2/M cell cycle arrest, and the cells at S phase decreased significantly. The occurrence of apoptosis detected by FCM increased significantly in the group treated with antisense FAK ODN.
Conclusions: Inhibition of FAK expression significantly decreases the attachment between ECM and Bel 7402 cells, and the ability of Bel 7402 cells to invade the reconstituted basement membrane. In addition, FAK suppression significantly inhibits the proliferation of Bel 7402 cells in vitro, and increases their apoptosis.