An Experimental Study Of Pro-apoptosis Effect Of Mifepristone On Androgen-dependent Prostate Cancer Cell Line LNCaPC₄ And Androgen-independent Prostate Cancer Cell Line LNCaPC_4-2,PC₃ In Vitro

Both the morbidity and the mortality rates from prostate cancer rise rapidly in china's elderly men in recent years,prostate cancer has becoming a severe threat to old men in our country. We could perform radical prostatectomy operation on early-stage prostate cancer patients. As late-stage prostate cancer is concerned, an adrogen-deprivation procedure could be taken firstly. This effect is usually palliative and temporary. The development of a hormone-independent state is an irreversible phenomenon observed in the majority of patients and occurs within an almost predictable life time of 12-18 months after the initiation of androgen deprivation. Results of radiotherapy and chemotherapy on androgen-independent prostate cancer has been incontent by now. so we need desperately a more effective and safer treatment method. Scholars abroad believe that antiprogestin mifepristone could induce the apoptosis of prostate cancer cell, especially that of androgen-independent prostate cancer cell, and inhibit proliferation of prostate caner cell. Using SRB protein-staining method, we studied the inhibition rates of different concentrations of mifepristone on the two type of cell lines. We also inspected apoptosis rates of the two cell lines using flow cytometry method.Our results demonstrate that: 1.Antiprogestin mifepristone could induce apoptosis of both androgen-dependent prostate cancer cell line LNCaPC4 and androgen-independent prostate cancer cell lines LNCaPC4-2,PC3 in vitro, it made no difference of the two type of cell lines. 2. the pro-apoptosis effect was time-and-dose dependent.3. using flow cytometry method, the apoptosis rates of 15 uM mifepristone on LNCaPC4-2 cell line were 19.30% and 30.04% respectively at 24h and 48h.The apoptosis rate of the same concentration of mifepristone on PC3 cell line at 24h was 44.52%.