Protein tyrosine phosphatase which stimulates progression from G1 into S phase during mitosis. Enhances cell proliferation, cell motility and invasive activity, and promotes cancer metastasis. May be involved in the progression of cardiac hypertrophy by inhibiting intracellular calcium mobilization in response to angiotensin II. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Inhibited by sodium orthovanadate and peroxovanadium compounds, and by pentamidine. Interacts with tubulin. Present in the small intestine, where it is located in the differentiated epithelial cells of the villus but not in the proliferating crypt cells (at protein level). Expressed in heart and skeletal muscle, and at lower levels in lung, spleen and testis. Down-regulated upon skeletal muscle denervation. Farnesylated. Farnesylation is required for membrane targeting. Unfarnesylated forms are shifted into the nucleus. Belongs to the protein-tyrosine phosphatase family.