Effects of blocking androgen receptor expression with specific hammerhead ribozyme on in vitro growth of prostate cancer cell line.

OBJECTIVE

To study the possibility of gene therapy for prostate cancer by blocking androgen receptor (AR) gene expression using a specific hammerhead ribozyme (RZ).

METHODS

The hammerhead ribozyme expression vector pcDNA-hAR-RZ, specific to AR mRNA, was constructed and transfected into the prostate cancer cell line LNCaP by using lipofectamine. Androgen receptor expression was measured by RT-PCR and immunohistochemical methods. Cellular proliferation activities were assayed using the tetrazolium bromide colorimetry method; cell cycle changes were observed by flow cytometry; and cell apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling method.

RESULTS

One to seven days after transfection with the ribozyme expression vector, AR mRNA expression at molecular and protein levels in LNCaP cells decreased by 32.6% - 40.7% (P < 0.05) and 21.0% - 87.64% (P < 0.05) respectively, and cell proliferation was inhibited by 18.28% - 35.34% (P < 0.05). Meanwhile, the cell cycle was arrested at the G2/M stage, and apoptotic morphological changes occurred with an apoptosis rate of 25.17% (P < 0.01).

CONCLUSION

Ribozyme specific against AR mRNA is capable of inhibiting the expression AR and inducing the apoptosis in prostate cancer cells.