KDM3A (also known as JHDM2A or JMJD1A) is an H3K9me2/1 demethylase. KDM3A performs diverse functions via the regulation of its associated genes, which are involved in spermatogenesis, metabolism, and cell differentiation. Lysine demethylase 3A (KDM3A) has been associated with metastasis and poor prognosis in several cancer types, including renal cell carcinoma, prostate cancer and Ewing sarcoma. The lysine demethylase 3A (KDM3A, JMJD1A or JHDM2A) controls transcriptional networks in a variety of biological processes such as spermatogenesis, metabolism, stem cell activity, and tumor progression. KDM3A plays a dual role by regulating actin gene expression and binding to the actin cytoskeleton, creating a responsive "actin gate" that involves ARP2/3 activity and IFT. KDM3A played a dual role in breast cancer cell invasion and apoptosis by demethylating histone and the non-histone protein p53, respectively.