Antitumor effect of CPT-11, a new derivative of camptothecin, against human prostate cancer (PC-3) in vitro and prostate rat tumor (AT-3) in vivo.

In an effort to evaluate the efficacy of CPT-11 on prostate cancer we utilized the PC-3 human prostate cancer cell line (in vitro), and the Dunning R3327 AT-3 rat prostate cancer tumor line (in vivo). PC-3 cells were initially seeded and cultured prior to the addition of CPT-11 at different concentrations 48 and 120 h later. After an additional 48 h the number of cells was determined using MTT dye uptake. CPT-11 at concentrations between 10 ng/ml and 50 micrograms/ml inhibited the growth of the PC-3 prostate human cancer cell line up < 0.001). AT-3 prostate rat cancer cells were injected into the right flank of 30 Copenhagen X Fischer rats, divided into treated and control groups. A total dose of CPT-11 (200 mg/kg) was given intraperitoneally, administered 1, 3 and 5 days postimplantation. We evaluated tumor growth by size and weight (5 and 10 days postimplantation). A total dose of 200 mg/kg inhibited the rapid growth of the prostate AT-3 tumor in vivo (p < 0.001).