Researchers at the University of Alcala in Madrid have discovered that cannabinoid compounds can significantly reduce cancerous tumors in mice.
http://www.reuters.com/article/healthNews/idUSTRE57I02Z20090819The cannabinoids tested by the Spanish team are thought to work against prostate cancer because they block a receptor, or molecular doorway, on the surface of tumour cells. This stops them from dividing.
In effect, the cancer cell receptors can recognize and "talk to" chemicals found in cannabis, said Diaz-Laviada.