“Prostate cancer is the most common malignancy among men of all races and one of the leading causes of cancer death in this population.

The palliative effects of Cannabis sativa (marijuana) and its putative main active ingredient, the Δ9-tetrahydrocannabinol (THC), which include inhibition of nausea and emesis associated with chemo- or radiotherapy, appetite stimulation, pain relief, mood elevation and relief from insomnia in cancer patients, have been well recognized for centuries. In addition to the therapeutic effects outlined above, THC, synthetic cannabinoid ligands and endocannabinoids or endocannabinoid-like substances have all been shown to induce cell death and to inhibit proliferation and/or migration of several murine and/or human cancer cell lines, as well as inhibiting the growth of certain types of tumours or tumour cell xenografts in vivo, including prostate cancer… the results in this paper represent a considerable experimental effort and provide a wealth of important information on how plant-derived, non-psychoactive, cannabinoids can induce apoptosis in prostate carcinoma cells through a variety of mechanisms… The results described in this paper also supplement previous evidence that THC can counteract prostate carcinoma in vitro and in vivo via activation of cannabinoid CB1 and CB2 receptors…” http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3570005/