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CBD Fights Cancer Through Various Mechanisms, Review Finds

A research review published in the Journal of Neuroimmune Pharmacology investigates how CBD elicits its anti-cancer effects.

Cannabidiol (CBD) and its antitumor properties are the focus of a recent literature review by researchers at the California Pacific Medical Center Research Institute. The team of investigators, led by cancer scientist Sean D. McAllister, PhD, examines the evidence explaining how the non-psychoactive cannabinoid inhibits the progression of many types of cancer. Their findings were published in the Journal of Neuroimmune Pharmacology.

CBD is one of the most abundant cannabinoids found in cannabis plants like marijuana and hemp. Within the body, cannabinoids like CBD interact with cannabinoid receptors of the endocannabinoid system to help modulate a wide array of physiological processes.

According to the research review, the plant-derived cannabinoid has shown in preclinical studies to elicit its anti-cancer effects by stimulating a range of chemical reactions that inhibit cancer cell survival and tumor progression. The administration of CBD has shown to produce reactive oxygen species (ROS), inhibit Id1 gene expression, and encourage autophagy-mediated cell death. ROS are chemically reactive chemical species containing oxygen have been found to suppress tumor growth when at high levels. Id1 has been shown to be a key regulator of the metastatic potential of certain cancers, and downregulating the Id1 makes cancer cells significantly less invasive. Autophagy is an intracellular degradation system that can destroy cancer cells.

Studies also indicate that when administered in combination with first-line therapies like radiation and chemotherapy, CBD enhances those treatments’ anti-cancer effects. In one study, by downregulating Id1 expression, CBD was able to effectively re-sensitize aggressive cancer cells to paclitaxel. In another, the anti-tumor effects of the drug temozolomide were enhanced by CBD, which upregulated autophagy-mediated death. The review also highlights another study, which found that a combination of CBD and tetrahydrocannabinol (THC) primed glioma cells to respond better to radiation.

“As presented in this review, the preclinical data strongly support the notion that non-psychoactive plant-derived [cannabinoids] can act as direct inhibitors of tumor progression as well as enhance the activity of first-line therapies,” McAllister concludes.

The review also points out that CBD does not produce any psychotropic effects and has a low toxicity profile, so large doses of the cannabinoid are likely possible.

“A cannabinoid drug treatment with a low toxicity profile that together produces direct antitumor activity and sensitizes tumors to existing first-line agents is an attractive therapeutic modality,” the review reads.

With preclinical evidence strongly supporting the notion that CBD can inhibit tumor progression, the review pushes for clinical research to further investigate CBD’s effects. It points out how legal restrictions surrounding Schedule I substances have severely hindered and delayed much-needed research that could eventually reveal a therapeutic application for CBD on cancer.

“While many anecdotal reports by cancer patients using various formulations of [cannabis] suggest significant efficacy, the lack of pure pharmacologically active compounds and legal restrictions surrounding schedule I drugs have delayed the clinical research that will ultimately determine whether cannabinoids are effective in the treatment of cancer beyond their proven palliative effects.”

You can read the entire research review, “The antitumor activity of plant-derived non-psychoactive cannabinoids,” via the National Center for Biotechnology Information.

Learn more about the research investigating cannabis’ potential therapeutic benefits for cancer by visiting our education page.