PTK2 and cancer: TG2 was shown to activate several oncogenic pathways, including the nuclear factor kappa-light-chain-enhancer of activated B cells/NF-κB, focal adhesion kinase/FAK, protein kinase B/Akt, β-catenin, Ras homolog family member A (RhoA), Yes-associated protein 1/YAP) which have been implicated in cancer progression [34,35,36,37,38] (Figure 2).