Studies have shown that cannabis has anti-tumor effects. A 1974 study, reported in the Washington Post newspaper feature, reported cannabis’s component,THC, “slowed the growth of lung cancers, breast cancers and a virus-induced leukemia in laboratory mice, and prolonged their lives by as much as 36 percent.”
 
In 1998, a research team at Madrid’s Complutense University Led by Dr. Manuel Guzman discovered that THC can selectively induce programmed cell death in brain tumor cells without negatively impacting surrounding healthy cells.

They reported in the March 2002 issue of “Nature Medicine” they had destroyed incurable brain cancer tumors in rats by injecting them with THC. And in 2007 even Harvard Researchers found that compounds in cannabis cut the growth of lung cancer.

There is also an organization called The SETH Group that showed compounds in cannabis can stop the growth of human glioblastoma multiforma (GBM) brain cancer cells. The SETH Group says “No chemotherapy can match this nontoxic anti-cancer action.” Even last year in 2012 a pair of scientists at California Pacific Medical Center in San Francisco found THC stops metastasis in many kinds of aggressive cancer.

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Patent No. 6630507, held by the United States Department of Health and Human Services, covers the use of cannabinoids for treating a wide range of diseases.

Under U.S. federal law, marijuana is defined as having no medical use. So it might come as a surprise to hear that the government owns one of the only patents on marijuana as a medicine.

The patent (US6630507) is titled “Cannabinoids as antioxidants and neuroprotectants” and was awarded to the Department of Health and Human Services (HHS) in October 2003.

It was filed four years earlier, in 1999, by a group of scientists from the National Institute of Mental Health (NIMH), which is part of the National Institutes of Health (NIH).

Watch as the active ingredient in marijuana, THC, kills cancer cells: