EGFR and ovarian carcinoma: However, the PKC activator PMA activated the phosphorylation of ERK, and the phosphorylation of ERK was inhibited by PKC inhibitor GF109203X, indicating that PAF activates ERK, the downstream target of EGFR, via PLCβ-dependent PKC and MMP-mediated EGFR pathways to promote ovarian cancer progression.