Knockdown of protein phosphatase 5 (PPP5C) suppresses the growth of leukemic cell line U937

Serine/threonine protein phosphatase 5 (PPP5C) participates in multiple signaling pathways including cell cycle control and cell growth. PPP5C is involved in the progression of human breast cancer and hepatocellular carcinoma. However, its function in acute myelogenous leukemia (AML) remains unknown. In this study, we constructed a lentivirus system to knock down the expression level of PPP5C in leukemic cell line U937. Cell proliferation and cell cycles were assessed by MTT assay and flow cytometry respectively. Western blot was used to determine the level of caspase-3, PARP (poly ADP-ribose polymerase), CDK4 and CyclinD1. Knockdown of PPP5C suppressed the proliferation ability of U937 cells, and led to G0/G1 phase arrest, inducing cell apoptosis in U937 cells. The apoptosis of the U937 cells was associated with upregulating cleaved caspase-3 and PARP, and downregulating CDK4 and CyclinD1. In conclusions, PPP5C knockdown inhibits U937 cell proliferation and might be used as a potential therapeutic target for the treatment of leukemia.