Abstract: Objective To study the effect of poly(C) binding protein 2 (PCBP2) silencing on P53 related genes and glioma cell proliferation. Methods PCBP2 gene-specific siRNA or control siRNA was transfected into three glioma cell lines (T98G, U87MG and U251). The expression levels of PCBP2 protein, P53 and its target genes PUMA and BAX, P53 co-regulator FHL2 and another member of the Four-and-a-half-LIM domain (FHL) family FHL1 were detected by Western blot. The interactions between PCBP2 and FHL family members’ mRNA were analyzed by Biotin pull-down. Cell proliferation was determined by BrdU incorporation. The apoptosis ratio of cells was measured by Hoechst staining. Results After transfection of PCBP2 siRNA, PCBP2 protein was evidently silenced; the protein levels of P53 and its target genes PUMA and BAX were increased (P < 0.05); the protein level of FHL2 was decreased (P < 0.05) but its mRNA 3’UTR didn’t bind to PCBP2, the BrdU positive cells decreased (P < 0.05); the number of Hoechst positive cells increased (P < 0.05). Conclusions Knockdown of PCBP2 can enhance the activity of P53 pathway in glioma cells with the weakened ability of cell proliferation and induction of cell apoptosis.

Key words: Key word: RNA interference, poly(C) binding protein 2, P53, cell proliferation, cell apoptosis