Given that oxidation can regulate protein-tyrosine phosphatase (PTP) catalytic activity, inactivation of an ABL-directed PTP by ROS might account for ABL1 activation in this malignancy.
SHP2 (Src homology 2 domain-containing protein tyrosine phosphatase 2; PTPN11) is a ubiquitous multidomain, nonreceptor protein tyrosine phosphatase (PTP) that plays an important role in diseases such as cancer, diabetes, and Noonan syndrome (NS).
Protein tyrosine phosphatase receptor‑type O (PTPRO), a member of the PTP family, has been frequently reported as potential tumor suppressor in many types of cancer.
Epigenetic inactivation of protein tyrosine phosphatase receptor-type O (PTPRO), a new member of the PTP family, has been described in several forms of cancer.
We have reported PTP gamma expression was downregulated by 17 beta-estradiol (E2) and Zeranol (Z) and that PTP gamma may function as an estrogen-regulated cancer suppressor in human breast.
The results show that PTP gamma mRNA is expressed in primary cultured human breast cells isolated from mammoplasty and breast cancer patients, as well as in human cancer cell lines, and that E2 significantly inhibits PTP gamma expression in ER-positive human breast cancer cells via an ER-mediated mechanism.