The role of IFITM3 in the growth and migration of human glioma cells.

Interferon induced transmembrane protein 3 (IFITM3) is transcribed in most tissues and highly interferon-inducible. However, the role of IFITM3 in cancer is still poorly understood. Expression levels of IFITM3 were analyzed in 60 glioma patients by immunohistochemistry (IHC). Following closely, we investigated the phenotype of IFITM3 knockdown on glioma cell growth and tumorigenesis in vitro using lentivirus-mediated loss-of-function strategy. Depletion of IFITM3in U251 cells dramatically inhibited cell proliferation and colony formation, which demonstrated that reduced IFITM3 protein levels could cause inhibition of tumorigenesis. Knockdown of IFITM3 also induced cell cycle arrest in G0/G1 phase, especially in the sub-G1 phase representing apoptotic cells. In addition, the migration of U251 cells was visibly weakened after IFITM3 knockdown, as determined by Transwell assay. Our findings provide new evidence that IFITM3 plays an important role in glioma cell growth and migration, suggesting that silencing of IFITM3 by RNA interference (RNAi) may be a potential approach to suppress glioma growth.