Daijiworld Media Network – New Delhi
New Delhi, Dec 20: Researchers have found that two widely studied cannabis compounds — tetrahydrocannabinol (THC) and cannabidiol (CBD) — demonstrate strong anti-tumour effects against ovarian cancer cells in laboratory studies, opening new avenues for future cancer research and treatment strategies.
THC, the primary psychoactive component of cannabis, and CBD, a non-intoxicating compound, are already used therapeutically to manage symptoms such as nausea and chronic pain. Both belong to a group of compounds known as cannabinoids, which interact with the body’s endocannabinoid system. Cancer research is emerging as one of the most active areas of study involving these compounds.
While previous laboratory studies have shown anticancer effects of THC and CBD in cancers such as brain, breast, lung and prostate, gynecological cancers — particularly ovarian cancer — have remained relatively underexplored. New research published in Frontiers seeks to bridge this gap.
The study found that both THC and CBD were effective in killing ovarian cancer cells and slowing key markers associated with tumour growth. Importantly, a combination of the two compounds, especially in a 1:1 ratio, produced the strongest anticancer activity.
“Our findings align with existing research showing that CBD and THC can act as potential adjuncts to cancer therapy,” said Dr Siyao Tong, attending obstetrician and gynaecologist at the First Affiliated Hospital of Jinzhou Medical University in China, and lead author of the study. He added that the compounds showed clear inhibitory effects on ovarian cancer cells.
The researchers tested the compounds on two ovarian cancer cell lines — one sensitive to platinum-based chemotherapy and the other resistant. Both responded to THC and CBD exposure, though the platinum-resistant cells required higher doses, suggesting potential value in difficult-to-treat cases.
Notably, the study found that THC and CBD exhibited “selective cytotoxicity,” meaning they killed cancer cells at much lower doses than those needed to harm healthy cells. This selectivity is considered a crucial factor in assessing the therapeutic potential of any anticancer agent.
The study also highlighted a synergistic effect when THC and CBD were used together, a phenomenon often referred to as the “entourage effect.” This synergy enhanced their effectiveness compared to when each compound was used alone.
Further analysis suggested that the cannabinoids reduced cancer cells’ ability to divide and regrow, triggered programmed cell death in about 25 per cent of cancer cells, reduced metastatic potential, and inhibited key signalling pathways responsible for cell growth and survival.
Experts caution that while the findings are promising, the research is still at an early stage. Extensive animal studies and clinical trials in humans will be required before any treatment could be approved.
Dr Elena Ratner, professor of obstetrics and gynaecology at Yale School of Medicine, who was not involved in the study, described the findings as encouraging. “This is a field in urgent need of new approaches. While it’s early, these results suggest real potential,” she said.
Dr Tong said THC and CBD could eventually be used alongside standard chemotherapy to help overcome drug resistance while also improving patients’ quality of life due to their anti-inflammatory, anti-nausea and pain-relieving properties.
Ovarian cancer remains one of the deadliest gynaecological cancers, often diagnosed at a late stage due to vague symptoms. In the US alone, around 20,000 cases and over 12,000 deaths were estimated in 2025.
For clinicians already using medical cannabis to manage symptoms, the possibility of added anti-cancer benefits is particularly encouraging. “If cannabis can help both symptom control and cancer biology, that would be remarkable,” Ratner noted.