MMP9 and prostate cancer: Moreover, we also investigated the expression of androgen-independent prostate cancer-associated proteins including MMP-9, MMP-2, AGTR1, MEK1/2, p-MEK1/2, ERK1/2, p-ERK1/2, STAT3, p-STAT3, PAX2, p-PAX2, and VEGF, which are also consensually considered to be related with cell proliferation, migration, and invasion of prostate cancer cells.