PTPN11 and liver cancer: In addition, sorafenib, an inhibitor of RAF and multiple other kinases [30,31] approved for the treatment of advanced renal and liver cancer, inhibits STAT3 phosphorylation, possibly by activating the phosphatase shatterproof 2 (SHP2), as knockdown of SHP2 expression inhibited sorafenib-induced STAT3 phosphorylated Y705 (pY705) dephosphorylation [32,33].