PrLZ is a novel recent isolated gene and specific expression in prostate tissues. PrLZ expression was specifically elevated in prostate embryonic tissues and androgen independent prostate cancer cells, suggesting it might be association with the embryonic development and malignancy progression. However, the function and mechanism of PrLZ during the progression of prostate cancer remain blurred. Our present studies showed PrLZ expression might enhance the proliferation and invasion capability in vitro and also increase the tumorigenicity in situ prostate cancer animal model, which is indicated PrLZ expression contributed to the malignancy progression of prostate cancer. In addition, PrLZ also might up regulate androgen receptor (AR) expression and increase the PSA expression, a putative downstream target gene of AR, which indicated PrLZ mediated the malignancy progression of prostate cancer was associated with androgen signals.