Can Hakan be wrong?
Both cannabis and immunotherapy have gained traction in the field of oncology in recent years — one to help treat symptoms, the other as a gentler alternative to chemotherapy — but there has been some concern that for cancer patients using both, the former could interfere with the latter.1 2 A newly published study in European Journal of CancerAnd3 However, he points out, there may be nothing to fear.
called drugs Immune checkpoint inhibitors It is a form Immunotherapy that has changed — with better targeting and less severe side effects — the treatment of many cancers, including non-small cell lung cancer (NSCLC).NSCLC). Immune checkpoint inhibitors are routinely given as first-line treatments for NSCLCEither alone or in combination with chemotherapy.
Cannabis has also become widely used among cancer patients over the past decade, in parallel with its increasing societal acceptance and expansion of its medical use. In addition to preclinical research and anecdotal accounts that cannabis may have anti-cancer effects, cannabis is also known to relieve many of the symptoms and side effects of cancer and cancer treatment, including nausea, pain, and suppressed appetite.
Red flags from previous studies
Concerns about the potential incompatibility between these two therapies stem from the fact that cannabinoid receptors CB2 It is predominantly expressed by immune cells, and its activation may suppress immune function. Immunotherapy such as immune checkpoint inhibitors rely on a robust response to do their work. It is at least plausible, then, for cannabis to interfere with immunotherapy: instead of helping, it might actually be painful.
In fact, this is exactly what was done in two previous studies from an Israeli research team in 20194 and 20205 They suggested — though, as the authors of the new paper, also based in Israel, argue right off the bat, these earlier findings come with some pretty big caveats. These studies included and were given patients with different types of cancer, treatment regimens, and treatment lines [immune checkpoint inhibitors] In the advanced line shortly before death,” the authors write. “Under these circumstances, cannabis use is often merely a surrogate for high-symptomatic disease burden.”
It is not surprising to find two research teams in Israel addressing the same question. Not only is the country a world leader in cannabis science, but medical cannabis is the most prescribed drug for cancer patients nationwide, used by more than 10,000 individuals, according to the authors of the new paper.
THC for oncology?
To further investigate the question of whether cannabis might reduce the effectiveness of immune checkpoint inhibitors, they folded two separate tests into the new study: a retrospective observational human study. NSCLC Patients, and a laboratory experiment using a mouse model of colorectal cancer.
The human study in itself is noteworthy. Although there is plenty of preclinical evidence demonstrating the anti-cancer effects of cannabis, clinical trials looking at relationships between cannabis use and cancer outcomes in actual patients are scarce. The best and most reliable types of clinical trials are carefully organized upfront, randomized, and controlled, but this retrospective observational study (where relationships between variables were reviewed after the fact via detailed medical records) is at least a step in that direction.
Acknowledging the limitations of the study is important, but the bottom line is clear. Among 201 lung cancer patients at the Sourasky Medical Center in Tel Aviv receiving the immune checkpoint inhibitor pembrolizumab as first-line treatment, the rate of tumor progression over years of clinical follow-up was similar among patients prescribed medical cannabis during the first month of treatment (n=102). ) and patients who were not prescribed cannabis (n = 99). In addition, no significant differences in overall survival were observed between the two groups of patients.
In the animal part of the study, the researchers treated a total of 30 tumor-bearing mice with either: 1) high;THC hemp extract (in two different concentrations); 2) an immune checkpoint inhibitor drug; 3) immunotherapy plus cannabis (again in two different concentrations); or 4) an inactive control vehicle, with seven to nine individuals in each group. Tumor size and survival rate were evaluated in the mice over the following weeks and months.
sigh of relief
Here, again, the researchers’ findings are unequivocal—and, importantly, consistent with the findings of the human study. Cannabis treatment did not change the effectiveness of immunotherapy (for better or worse). In addition, the cannabis-only mice were slightly better than the mice in the control group in terms of tumor growth rate and survival rate.
Our data indicate that cannabis use in conjunction with [immune checkpoint inhibitors] It does not reduce the effectiveness of the treatment NSCLCWith the increase in the use of medical cannabis worldwide, this finding is of great clinical importance.
Future work (ideally in the form of randomized clinical trials, or at least prospective clinical trials, to produce the best possible evidence) could test the applicability of these findings to other cancers, treatment combinations, and cannabis extracts. But for now, at least, they may offer—as the paper’s title suggests—a “sigh of relief” to those interested in cannabis’ role in cancer immunotherapy.