TGFA and granular cell tumor: Our previous report indicated that TGFα, via regulating PI3K/AKT pathway, stimulates GCT progression.35 Knockdown of FHL2 in KGN cells nearly eliminated TGFα-induced activation of PI3K/AKT pathway, which was indicated by inhibition of the phosphorylation of AKT, S6K and S6 after treatment of FHL2-knockdown KGN cells with TGFα (Figure 5a).