Tyrosine-protein phosphatase non-receptor type 6 (SHP-1) and Tyrosine-protein phosphatase non-receptor type 11 (SHP-2) (SHP-1 (for PTPN6) and SHP-2 (for PTPN11))

SHP-1 and SHP-2 are closely related, non-receptor protein tyrosine phosphatases characterized by the presence of two N-terminal Src homology 2 (SH2) domains and a C-terminal catalytic phosphatase domain[1][8]. SHP-1 (encoded by the PTPN6 gene) is predominantly expressed in hematopoietic tissues and acts mainly as a negative regulator of signaling from cytokine and growth factor receptors, inhibiting immune cell activation and proliferation, and playing a key role in downregulating immune responses and maintaining self-tolerance[3][5][7]. SHP-2 (encoded by PTPN11) is ubiquitously expressed and acts as a positive mediator in multiple signaling cascades triggered by growth factors or cytokines, positively regulating cell proliferation, differentiation, and survival, and is essential for normal development and various tissue functions[6][8]. SHP-2 is frequently mutated (gain-of-function) in juvenile myelomonocytic leukemia, Noonan syndrome, and several cancers; SHP-1 is often downregulated in lymphomas and leukemias, where it normally suppresses oncogenic signaling. Both phosphatases are central to signaling through the Ras/MAPK, PI3K/AKT, and JAK/STAT pathways. Their opposing regulatory roles in hematopoietic signaling networks make them both important but complex therapeutic targets, with ongoing development of small-molecule modulators for disease intervention[1][2][3][6][8].

Other names

PTPN6SH-PTP1PTP1CHCPHcphPTPN11SH-PTP2PTP1DPTP2cSHPTP-3SYP

Inhibition of phosphatase activity blocks downstream dephosphorylation, thus modulating pathways such as Ras-MAPK, PI3K-Akt, Jak-STAT, and immune receptor signaling[2][6]. Modulation (typically inhibition) of SHP-2 can enhance T-cell activity in cancer immunotherapy ([4]).