A recent research review led by Dr. Guillermo Velasco of Complutense University of Madrid and published in Current Oncology looked into previous studies that examined the molecular mechanisms of the actions cannabinoids use to combat cancer. In the review, the researchers discuss how THC and CBD interact with CB1 and CB2 receptors to initiate chemical reactions that suppress tumor growth. To highlight the importance of the CB1 receptor, one animal study found removing CB1 receptors accelerates tumor growth in the intestines. Another found cannabinoids that interact with CB1 receptors reduce levels of cancerous precursors. Additionally, the removal of enzymes that harm cannabinoids results in the reduction of tumor growth in mice. Through binding to CB1 and CB2 receptors, cannabinoids impair the progression of tumors and induce apoptosis which kills cancer cells and prevents them from spreading.
Other preclinical studies have found cannabinoids stimulate the production of ceramide, a compound known to induce apoptosis, and enhance the expression of p8 (NUPR 1), a stress regulated protein that stimulates autophagy mediated cancer cell death and regulates tumorigenesis and tumor progression. CBD is also able to promote apoptotic death in cancer cells independently of CB1 and CB2 receptors. Cannabinoids also work together with anticancer drugs to reduce tumor growth, and THC and CBD when combined with radiotherapy or cancer drugs enhance anti-cancer effects. Valesco Concludes, “To summarize, cannabinoids induce tumour cell death and inhibit tumour angiogenesis and invasion in animal models of cancer, and there are indications that they act similarly in patients with glioblastoma... Given that cannabinoids show an acceptable safety profile, clinical trials testing them as single drugs, or ideally, in combination therapies in glioblastoma and other types of cancer are both warranted and urgently needed.”