Overexpression of PRDM5 promotes acute myeloid leukemia cell proliferation and migration by activating the JNK pathway

PRDM family proteins are dysregulated in many human diseases, especially hematological malignancies and solid cancers, and share a unique N-terminal PR domain followed by zinc fingers toward the C terminus. With a high frequency of DNA promoter hypermethylation, PRDM5 is primarily considered as a tumor suppressor in solid tumors. However, little is known about the function of PRDM5 in blood malignancies, especially acute myeloid leukemia (AML). In this study, we showed that high PRDM5 expression levels were independently correlated with poor overall survival in AML patients. PRDM5 overexpression promoted cell proliferation, colony formation, and migration in vitro and enhanced tumorigenesis in an in vivo xenograft model. Furthermore, we found that PRDM5 overexpression promoted cell cycle progression with the decreased level of cell cycle inhibitors such as p16 and p21, and regulated the expression of epithelial-mesenchymal transition markers ZO-1 and Vimentin to promote migration. Moreover, we observed that PRDM5 upregulated the Jun N-terminal kinase (JNK) signaling pathway and downregulated c-Myc expression. Pharmacological inhibition of JNK by SP600125 partially abrogated PRDM5-induced cell proliferation and migration. Taken together, our findings demonstrate that PRDM5 functions as an oncogenic driver in AML via JNK pathway, suggesting that PRDM5 is a potential therapeutic target for AML.