PTPA and cancer: Moreover, the activation of p-ERK1/2 is under the control of MAP3K2 via its regulatory roles for NF1, K-Ras and PP2A [22, 23] MAP3K2-ERK1/2 signaling pathway is thought to modulate the activation or expression of the STAT3, MMPs, survivin and cyclin D1, thus facilitating the invasion, metastasis and proliferation of cancer cells.