A Harvard study from 2007 which remains the most comprehensive ever released on THC’s potential to combat tumors found that in just three weeks doses of THC were able to cut lung cancer tumor growth in half in mice subjects, and were able to reduce cancer lesions by even more. 
For the study, Harvard researchers tested THC (delta-9-tetrahydrocannabinol, which is found naturally in cannabis) on cancer cells in labs, and followed that up by studying mice subjects.
The lab demonstration found that doses of THC inhibited growth and spread in the cancer cells; “When the cells are pretreated with THC, they have less EGFR stimulated invasion as measured by various in-vitro assays,” states Anju Preet, PhD, who was one of the researchers for the study.
Read moreHarvard Study Finds Cannabis Cuts Tumor Growth in Half in Three Weeks