Karyopherin alpha 2 induces apoptosis in tongue squamous cell carcinoma CAL-27 cells through the p53 pathway

摘要

Tumor onset and progression are associated with dysfunction of the nuclear transport machinery at the level of import and export receptors. However, the role of Karyopherin alpha 2 (KPNA2) in human tongue squamous cell carcinoma (TSCC) remains unknown. We assessed the proliferation, apoptosis and migration of TSCC CAL-27 cells using wound healing, Transwell and MTT assays, western blotting, electron microscopy and acridine orange/ethidium bromide staining following knockdown of KPNA2. The results revealed the antiproliferative, proapoptotic and anti-migratory effects of KPNA2 silencing on the TSCC CAL-27 cells. Moreover, the knockdown of KPNA2 proved to be accompanied by the upregulation of active caspase-3, cytochrome c, Bax, Bad and decreased expression of Bcl-2, p-Bad and XIAP. KPNA2 activated the caspase-dependent pathway in the CAL-27 cells with upregulation of p53, p21(Cip1/Waf1) and p16(INK4a). Thus, the present study demonstrated that p53/p21(Cip1/Waf1)/p16(INK4a) may be an important pathway involved in the function of KPNA2 in TSCC CAL-27 cells.