Cannabis and ovarian cancer: continuing Michelle Kendall’s legacy

A recent study found promising effects of cannabis in the treatment of ovarian cancer, offering a glimmer of hope to women across the globe.

Cannabis Health spoke to Bruce Kendall and Professor Hinanit Koltai about the remarkable story – and woman – behind it. 

Michelle Kendall believed that finding the right combination of cannabinoids could save her life. 

After Michelle was diagnosed with terminal ovarian cancer in 2016 at the age of 43, it was a neighbour at her home in Santa Barbara, California, who suggested she try cannabis to manage her symptoms. He was a retired family doctor, who had taken on medical cannabis as a retirement project and grew his own to manage arthritis pain.

Once she started taking cannabis regularly to manage the side-effects of the chemotherapy, at her hospital appointments, Michelle noticed that her cancer antigen markers were going down.

But it was after returning from a trip to the Galapagos Islands, where she had been without access to cannabis for three weeks – and seeing how her markers had increased significantly – that she became convinced something more than symptom management was going on. 

A former biologist and scientist by nature, Michelle began to look for the research. She wasn’t satisfied playing a guessing game when it came to which strains or cannabinoids were the most effective. Except, at the time, there was no research on cannabis and ovarian cancer. 

In her 2020 documentary Schedule One, which was due to premiere at the Los Angeles Short Film Festival when the pandemic hit, Michelle shares her journey to raise awareness of the strict regulations around cannabis which have prevented so much vital research being done. 

When the lockdown restrictions meant the premiere couldn’t go ahead, she set about emailing international researchers who were already working in the field of cannabis and cancer. 

Professor Hinanit Koltai has worked as a scientist at the Volcani Institute in Israel for more than 20 years, the last seven of which she has specialised in the medicinal properties of cannabis. 

“Michelle wrote me a very short and simple email asking if I was working on studies on ovarian cancer and with cannabis and if I would be interested in doing that, and shortly after we had our first Zoom meeting,” says Hinanit. 

“I was completely captivated by her personality, enthusiasm and hope.”

Bruce and Michelle Kendall in ‘happier times’.

A potential ‘anti-cancer’ treatment

Michelle and her husband, Bruce Kendall, kept in regular contact with Hinanit while her laboratory began to explore the possibility of cannabis as a treatment for ovarian cancer. Michelle even had some of her own cancer cells isolated and sent to the lab for examination as part of the research. 

Hinanit explains: “The question that we asked is ‘What compounds in cannabis are the active ones? And what combination of molecules is optimal?’ Cannabis contains so many different compounds and there are several dozen in each strain, so patients, even if they have a very effective strain, have no idea what is working and neither do their doctors.

“We were not just asking whether cannabis works, but what compounds need to be present for the most effect, and we asked this specifically in relation to ovarian cancer.”

Hinanit’s team extracted the molecules from different cannabis strains and determined the strain with the highest activity. They then carried out further tests to find the best combination of compounds against ovarian cancer cells.

“This turned out to be a combination of THC, with CBC and CBG,” says Hinanit.

“This combination works better than THC alone, and it also works better than the whole extract.”

Using a purified formulation of the molecules, Hinanit and her team were then able to demonstrate that this specific combination of compounds led to cell apoptosis – or programmed cell death – and was 50 times more effective on cancer cells than on healthy ones. 

Positive synergies were also found between the cannabinoids and the chemotherapy drug niraparib, in both the petri dish and in Michelle’s cells, with cell death rates being far higher when the two therapies were used together than would be expected from the additive effects of the two treatments alone. In contrast, there was no synergy between cannabis and the chemotherapy drug gemcitabine, which has a very different mode of action from niraparib.

These promising findings led to the conclusion that cannabis could be a ‘complementary and effective anti-cancer treatment’ for ovarian cancer, with more extensive clinical trials ‘desperately needed’. 

You can read the full study here.

Putting ovarian cancer in context

Ovarian cancer is the second most common and most lethal gyneacologic cancer in the Western world, with around 70% of cases being diagnosed at an advanced stage. With the main symptoms, such as bloating and stomach pain, being easy to disregard, many women go for months without a diagnosis. 

In about 80% of the cases, patients will relapse and develop resistances to the available drugs, with very few women surviving more than five years after diagnosis.

Sadly, this was the case for Michelle. She passed away in September 2021 after developing a reaction to the chemotherapy drug that was slowing the growth of her tumours. She chose to end her life in celebration, surrounded by loved ones at her home in Santa Barbara.

“In her indomitable way she made it into a celebration,” says Bruce.

“She invited 30 friends and family, and we were all there together with her as she fell asleep. It was quite extraordinary. It was an extraordinary passing to match an extraordinary life.”

Michelle’s cancer battle came to an end in September 2021.

Hinanit and her team had kept Michelle up to date with the findings throughout the process, and she was able to see a preprint of the paper before it was submitted for peer-review.

“Michelle was convinced that there was something there based on her own experience, and she was absolutely thrilled when we were able to start showing results,” Bruce recalls.

“She was very excited. In the last year of her life, this is what was giving her hope. On some level we were hoping that we would get to a formulation that would actually work for her, but we always knew that was kind of a long shot.”

He adds: “Michelle was just passionate about showing that cannabis could be an effective treatment for this disease, and this really was the one thing that kept her going.”

A spark of hope

Both Bruce and Hinanit are now fully committed to finishing what Michelle started. The research team, led by PhD student Nurit Shalev, is now pressing ahead with animal studies with a view to undertaking clinical trials as soon as possible. 

“This research is Michelle’s legacy, and we are very much committed and proud to carry it on,” says Hinanit.

“It is very important, not just for scientific knowledge but to be able to proceed to clinical trials, which are an important part of the process of regulation and approval of a medicine. We believe this research will be able to support the development of new cannabis-based products that could be designated for the treatment of cancer.”

Bruce adds: “The importance of clinical research is not just so that we can market a pharmaceutical drug. Physicians and oncologists are not going to prescribe something until they can see clinical trials that demonstrate its effectiveness.

“We are sometimes asked, ‘Why go down the pharmaceutical route at all? Why not just encourage patients to take cannabis?’ The answer is that there are hundreds of active compounds in cannabis and not all of them are effective. Some of them may be counter-effective. 

“Michelle used to draw the analogy that it’s like going to your oncologist and them showing you a cabinet of chemotherapy drugs and asking you to just pick one.”

Bruce is dedicated to continuing his wife’s legacy.

With some way still to go, how does Bruce balance the passion for pursuing what was so important to her, with the grief of losing his wife of 14 years?

“It’s a way that I can stay connected to her and her energy, her vision and her passion. But as part of the grieving process, the more connected we stay with the one who’s gone, the more it brings up hard emotions, and so it is sometimes challenging,” he admits. 

“Earlier this week I was listening to a podcast that she had recorded in 2020, and it just reminded me how inspirational she was, but it also brought tears, for sure.”

Michelle may not have had enough time to see the potential of cannabis in treating ovarian cancer first-hand, but her contribution to science has lit a spark of hope for millions of other women around the world. 

She may even have carved a path towards a cure. 

“We will continue Michelle’s legacy to come up with a new and effective treatment for ovarian cancer,” Bruce adds.

“Even if it’s not a cure, even if it’s just another part of the toolkit, I would be absolutely thrilled and I know that Michelle would be, too.”

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