Indeed, a number of chemotherapeutic drugs (49–52) as well as Shp1-targeting natural compounds (40, 53, 54) induce Shp1-mediated dephosphorylation of p-STAT3Tyr705; this downregulates STAT3 transcriptional activity causing a block of tumor cell proliferation and induction of apoptosis. This evidence concerns the gene PTPN6 and neoplasm.