Combined low-dose imatinib mesylate and paclitaxel lack synergy in an experimental model of extra-osseous hormone-refractory prostate cancer

Abstract

OBJECTIVE: To determine the efficacy of low-dose imatinib mesylate (STI571) alone or combined with a taxane (paclitaxel) in inhibiting the growth of experimental extra-osseous hormone-refractory prostrate cancer. MATERIALS AND METHODS: Orthotopic PC3 prostate tumours were established in male severe combined-immunodeficient mice; on day 3 the mice were randomly assigned to one of four groups: paclitaxel 10 mg/kg intraperitoneally once a week; STI571 50 mg/kg once a day for 6/7 weekdays; combined paclitaxel and STI571; and vehicle-treated controls. On day 40, the primary prostate tumour and metastatic lymphadenopathy were removed and measured. Effects were correlated with tumour cell prolifera..