Serine and arginine-rich splicing factor-1 gene affects the proliferation of glioma U87 cells by regulating the translation process / 中国肿瘤生物治疗杂志

ABSTRACT

@# Objective: To investigate the effect of serine and arginine rich splicing factor 1 (SRSF1) on proliferation and cell cycle of U87 cells and to explore the underlying mechanisms. Methods: Gene silencing technology was used to knockdown SRSF1, and stable SRSF1 knockdown cell lines with two different targeting sites (shSRSF1-1 and shSRSF1-2) were obtained. Cell counting kit (CCK-8) was performed to detect proliferation of U87, and flow cytometry was performed to detect cell cycle of U87 with or without SRSF1 knockdown. qPCR and WB were used to detect the mRNA and protein expressions of cell division related genes (CEP70 and SMC4). WB was performed to detect the effect of SRSF1 knockdown on phosphorylation of translation initiation protein 4E-BP1. Results: Compared with control group, the protein level of SRSF1 was significantly decreased in U87 cells of shSRSF1-1 and shSRSF1-2 groups ( P <0.01), and the proliferation was significantly decreased (P<0.01); in addition,U87 cells were remarkably arrested at G2 phasein shSRSF1-1 and shSRSF1-2 groups (P<0.01). Although the mRNA levels of CEP70 and SMC4 did not change significantly ( P >0.05), the protein levels of CEP70 and SMC4 were lower in U87 cells of shSRSF1-1 and shSRSF1-2 groupsas compared with control group (all P<0.01). And the levels of phosphorylated 4E-BP1 were also inhibited in U87 cellsof shSRSF1-1 and shSRSF1-2 groups as compared with control group ( P <0.01). Conclusion: SRSF1 knockdown decreased the phosphorylation of 4EBP1 and inhibited the translation process of CEP70 and SMC4, there by resulting in cell cycle retardant in G2 phase and proliferation repression of glioma U87 cells.