[The synergistic effects of paclitaxel and gemcitabine on prostate cancer cell line PC-3]

To observe the synergistic effects of paclitaxel and gemcitabine on prostate cancer cell line PC-3 in vitro.

Cell morphology, MTU, flow cytometer and immunocytochemical method were used to observe the effects of 10(-6), 10(-7), 10(-8) mol/L paclitaxel and 10(-7), 10(-8), 10(-9) mol/L gemcitabine on prostate cancer cell line PC-3 by single or synergistic administration for 48 hours in vitro.

Gemcitabine above 10(-8) mol/L enhanced the growth suppression [suppression ratio > or = (50.8 +/- 4.2)%, P < 0.05] and apoptosis [apoptosis ratio > or = (22.9 +/- 2.3)%, P < 0.05] and down-regulation of the expression of cyclin D1 [expression ratio < or = (9.6 +/- 1.6)%, P < 0.01] induced by paclitaxel above 10(-7) mol/L in PC-3 cells. Gemcitabine changed the ratio of G2/M cell arrest induced by paclitaxel from (70.3 +/- 9.7)% to (38.2 +/- 4.2)%, and reversed the G2/M arrest partially (P < 0.01).

Paclitaxel and gemcitabine can enhance the growth suppression and apoptosis induced by paclitaxel in a synergistic way. They show great potential in the treatment of androgen-independent carcinoma of the prostate.