Cannabis compounds kill ovarian cancer without harming healthy cells, research finds

A combination of THC and CBD derived from cannabis was shown to kill ovarian cancer cells without harming healthy cells in laboratory studies.

The findings suggest that drugs made from these compounds could be developed to fight ovarian cancer in future, though researchers caution that much more work is needed before results can be translated into patient treatments.

The research was led by Dr Siyao Tong of Khon Kaen University.

The researcher said: “Ovarian cancer remains one of the deadliest gynaecological malignancies, characterised by late diagnosis, high recurrence rates, and limited effective treatment options.

“Our goal is to find alternative drugs that can improve efficacy and potentially reduce toxicity, ultimately bringing new hope to patients facing this challenging disease.”

Scientists tested the effects of CBD (cannabidiol, which is not psychoactive) and THC (delta-9-tetrahydrocannabinol, which is) on two ovarian cancer cell lines.

One line was sensitive to platinum-derived drugs and one was resistant.

The team found that cells from both cancer lines treated with CBD or THC formed fewer and smaller colonies.

While both compounds limited cancer cell growth, combining them produced particularly strong results.

A combination of the two was very successful at killing cancer cells.

“Notably, the inhibitory effect was most pronounced when CBD and THC were used in a 1:1 ratio,” said Tong.

Additional tests showed the compounds prevented cells from migrating, suggesting they might be able to stop ovarian cancer spreading to other parts of the body.

Both cell lines were similarly affected, indicating the compounds could work equally well for different types of ovarian cancer. The compounds also had minimal effects on healthy cells.

To explore how this worked, scientists examined cell signalling pathways. The PI3K/AKT/mTOR pathway, which regulates cell growth and survival, is overactive in ovarian cancer cells and contributes to tumour development and treatment resistance.

The CBD and THC combination appeared to restore normal regulation of the pathway.

Tong said: “Although our study is still preliminary, it lays an important foundation for future research into the potential applications of CBD and THC in ovarian cancer treatment.

“By confirming their anti-cancer activity and identifying key molecular mechanisms, our findings are expected to drive further preclinical research.

“If future studies confirm these effects, CBD-THC combination therapy may ultimately contribute to the development of new treatment strategies.”