MAPK3 and prostate cancer: Since P2Y2 receptor predominantly mediates ATP-induced activation of EGFR and ERK1/2 as described above, and P2Y2 receptor is responsible for ATP-stimulated prostate cancer cell invasion and migration as demonstrated in our previous study [6], the results strongly suggest that P2Y2-EGFR-ERK1/2 pathway is involved in the regulation of prostate cancer cell invasion and migration.