Medical marijuana news. Cannabidiol stops the spread of breast cancer

California Pacific Medical Center Research Institute Final Report (2008)

We discovered that cannabidiol (CBD), a non-psychotropic compound from the plant Cannabis sativa, can inhibit the process of breast cancer cells that allow them to grow and spread (metastasis). CBD can also inhibit breast cancer metastasis in a mouse model. The research carried out in our CBCRP proposal demonstrated that CBD is a novel inhibitor of a gene whose activity is intimately linked to the aggressiveness of human breast cancers; this gene has been termed Id-1. Notably, our findings also indicated that Id-1 was a key gene whose expression needed to be reduced in order for CBD to inhibit aggressive breast cancer. One of the most significant high risk components of the initial application was to determine if CBD had appreciable efficacy against breast cancer in vivo (i.e., animal models). This high risk component was not pursued, since an independent group showed CBD was able to inhibit metastasis of MDA-MB231 cells to the lung of nude mice. Building of the previous findings, we made small structural changes to CBD that are expected to produce drugs that are much more active than CBD at inhibiting Id-1 and corresponding aggressive breast cancers. CBD has a low toxicity profile. An anticancer agent with a low toxicity profile that can both inhibit cancer cell growth and metastasis would be extremely valuable clinically. Understanding the mechanisms behind the anticancer activity of CBD may also lead to the discovery of new biological targets for the development of diagnostic tools and additional therapies for the treatment of cancer. In this project we found portions of the CBD structure essential to its biological activity for breast cancer cell growth inhibition. We are in the process of filing a patent on these discoveries. In addition, we studies the moleculr mechanisms that underlie CBD activity, and found that sustained upregulation of Erk (extracellular signal-regulated kinases, a type of protein kinase intracellular signaling molecules) is key to the ability of CBD to regulate the metastasis-specific inhibition of the Id-1 transcription factor.

Antioxidant activity has been reported to be a general property of the phenolic components of marijuana. Unlike Δ9-THC, cannabidiol can be administered at relatively high doses without undesired toxic or psychological effects.1 Cannabidiol at a concentration of 10 µM was neuroprotective against both excitatory neurotransmitter (glutamate) and oxidant (hydroperoxide) induced neurotoxicity.