Down-Regulation of PPP2R5C Expression Inhibits Proliferation in Leukemic T Cells Proliferation by RNA Interference

Abstract

Abstract 4678PPP2R5C is one of the regulatory B subunits of protein phosphatase 2A (PP2A), which is a major cellular serine/threonine phosphatase that affects the phosphorylation status of many proteins. Previous study showed that overexpression of PPP2R5C in T-cell malignancy might relate to its proliferation and differentiation. Investigation of the effect of target inhibition of this gene might be beneficial to further characterization of molecular mechanisms and targeted therapy in leukemia. The aim of the study is to design and screen the highly efficient and specific PPP2R5C-siRNAs which are able to downregulate the PPP2R5C gene expression in leukemic T cells and inhibit the tumor cells proliferation by RNA interference. PPP2R5C-siRNAs numbered 1, 2, or 3 and the scrambled nonsilencing siRNA control (SC) were obtained by chemosynthesis. Mock-transfected, sc-treated and untreated cells were used as controls. The PPP2R5C-siRNAs were delivered into Molt-4, Jurkat cells and primary T cells-acute lymphocytic leukemia (T-ALL) cells by nucleofection. PPP2R5C expression in mRNA and protein levels, cell proliferation, apoptosis and cell cycle were analyzed in cells after siRNAs delivered. The results showed that PPP2R5C-siRNA2 took best silencing result, PPP2R5C-siRNA3 followed. The proliferation rates of PPP2R5C-siRNA2 and PPP2R5C-siRNA3 treated Molt-4 and Jurkat cells were significantly decreased at 72h post treatment, the inhibition rate of the PPP2R5C-siRNA treated Molt-4 and Jurkat cells proliferation were 49.23±11.65% and 47.12±13.19% respectively. However, both siRNAs didn’t have obvious effects in apoptosis of leukemic cells as the significant change on the cell cycles. Similar effect was observed in PPP2R5C-siRNA2 treated primary T-ALL cells. In conclusions, two PPP2R5C-siRNAs which could targeted inhibit the proliferation in leukemic T cells were selected. Suppression of PPP2R5C by RNA interference could inhibit the proliferation effectively in leukemic T cells. Disclosures:Chen:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Liu:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Zheng:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Shen:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Wu:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Yang:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Chen:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Li:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding. Li:This work was supported by Grants from National Natural Science Foundation of China (no. 30871091), the Fundamental Research Funds for the Central Universities (No. 21610604), the Guangdong Science & Technology Project (No. 2012B050600023) and Science and: Research Funding.