In this study, we show that the expression level of stromal Dkk-3 is also relevant to prostate cancer, and we identify two secreted proteins, TGFBI (Transforming Growth Factor Beta Induced) and ECM-1 (extracellular matrix protein 1), whose levels are differentially affected by DKK3 silencing in prostate stromal cells and that appear to play opposing roles in prostate cancer. Here, ECM1 is linked to prostate cancer.