PTPN12 and cancer: This literature reported that both human cancers and normal tissues appeared to the missense mutations of PTPN12 gene, which could produce three mutant variants of PTPN12 protein consisting of two variants with normal or high expression and a variant with decreased expression of PTPN12 in the majority of human cancer samples by immunoblotting, and the majority of normal tissues were served as nonmutant variant with normal or high expression of PTPN12, and rare tissues were regarded as mutant variant with decreased expression of PTPN12.