PTK2 and cancer: Suppressor of cytokine signaling 1 has been shown to regulate, directly or indirectly, a number of molecules and pathways that have been implicated in cancer – CDK2, CDK4, Cyclin D1, MAPK/p38, PDL1, STAT1, STAT3, STAT6, p53, p21, FAK, E-cadherins, Met tyrosine kinase, type I and II IFN, and numerous proinflammatory cytokines (Liu, 2003; Ritz et al., 2008; Neuwirt et al., 2009; Souma et al., 2012; David et al., 2014; Gui et al., 2015; Yeganeh et al., 2016; Liau et al., 2018; Figure 4 briefly explains the mode of regulation by SOCS1).