The main psychoactive ingredient in cannabis could reduce tumor growth in cancer patients. New research has revealed previously unknown signaling platforms that are responsible for the drug’s success in shrinking tumors. These findings may help to develop a synthetic equivalent with anticancer properties.
The research team used samples of human cancer cells to induce tumors in mice, and then they targeted the tumors with doses of the cannabis compound THC (tetrahydrocannabinol). Two cell receptors in particular were found to be responsible for the antitumor effects of THC. This research was conducted at the University of East Anglia in Norfolk, United Kingdom, along with the Universidad Complutense de Madridin in Spain. It was published in the Journal of Biological Chemistry (2014; doi:10.1074/jbc.M114.561761).
“THC, the major active component of marijuana, has anticancer properties. This compound is known to act through a specific family of cell receptors called cannabinoid receptors. However, it was unclear which of these receptors were responsible for the antitumor effects of THC,” said Peter McCormick, PhD, of the University of East Anglia’s School of Pharmacy.
“We show that these effects are mediated via the joint interaction of CB2 and GPR55, two members of the cannabinoid receptor family. Our findings help explain some of the well-known but still poorly understood effects of THC at low and high doses on tumor growth.”
McCormick explained that understanding the molecular mechanisms behind how marijuana, and specifically THC, influence cancer pathology are of great interest. He stated that the pharmaceutical industry is seeking to create synthetic equivalents that might have anticancer properties.
McCormick stated that identifying the receptors involved is an important step towards the future development of therapeutics. These future therapeutics can take advantage of the interactions the research team discovered to reduce tumor growth.
McCormick added that patients with cancer should not be tempted to self-medicate. He said, “Our research uses an isolated chemical compound and using the correct concentration is vital. Cancer patients should not use cannabis to self-medicate, but I hope that our research will lead to a safe synthetic equivalent being available in the future.”