PTP4A3 protein tyrosine phosphatase which stimulates progression from G1 into S phase during mitosis. It enhances cell proliferation, cell motility and invasive activity, and promotes cancer metastasis. It may be involved in the progression of cardiac hypertrophy by inhibiting intracellular calcium mobilization in response to angiotensin II. PTP4A3 interacts with tubulin. It belongs to the protein tyrosine phosphatase family. It is mainly expressed in cardiomyocytes and skeletal muscle; also found in pancreas. It is consistently overexpressed in colon cancer metastasis.