Protective Effects of Cannabidiol on Chemotherapy-Induced Oral Mucositis via the Nrf2/Keap1/ARE Signaling Pathways

Archive of "Oxidative Medicine and Cellular Longevity". - PMC

“Oral mucositis (OM) is a common complication during chemotherapy characterized by ulceration, mucosa atrophy, and necrosis, which seriously interferes with nutritional intake and oncotherapy procedures among patients. However, the efficacy of current treatments for OM remains limited.

Cannabidiol (CBD) is a natural cannabinoid with multiple biological activities, including antioxidant and anti-inflammatory potential. In this study, we aimed to investigate the chemopreventive effects and mechanisms of CBD in protecting C57BL/6N mice and human oral keratinocytes (HOK) from 5-fluorouracil- (5-FU-) induced OM.

Here, we found that CBD alleviated the severity of 5-FU-induced OM in mice, including improved survival, decreased body weight loss, reduced ulcer sizes, and improved clinical scores. Histologically, CBD restored epithelial thickness and normal structure in tongue tissues. Meanwhile, CBD attenuated reactive oxygen species (ROS) overproduction and improved the antioxidant response, suppressed the inflammatory response, promoted the proliferation of epithelial cells, and inhibited 5-FU-induced apoptosis. In vitro, consistent outcomes showed that CBD suppressed cellular ROS levels, enhanced antioxidant ability, reduced inflammatory response, promoted proliferation, and inhibited apoptosis in 5-FU-treated HOK cells. In particular, CBD upregulated the expression levels of antioxidant enzymes, heme oxygenase-1 (HO-1) and NAD(P)H quinine oxidoreductase 1 (NQO1), by increasing the expression and nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and decreasing Kelch-like ECH-associated protein 1 (Keap1). Notably, the Nrf2 inhibitor ML385 reversed the protective effect of CBD. Nrf2-siRNA transfection also significantly blunted the antioxidant effect of CBD in in vitro OM model.

Collectively, our findings suggested that CBD protected against 5-FU-induced OM injury at least partially via the Nrf2/Keap1/ARE signaling pathways, highlighting the therapeutic prospects of CBD as a novel strategy for chemotherapy-induced OM.”

https://pubmed.ncbi.nlm.nih.gov/35669853/

“CBD alleviates chemotherapy-induced OM and protects against the toxicity of 5-FU by improving oxidative stress defense, downregulating mucosal inflammation, promoting cell proliferation, and inhibiting 5-FU-induced apoptosis both in mice and in HOK. Moreover, CBD-activated Nrf2/Keap1/ARE signaling pathways might be the underlying mechanism for OM recovery.”

https://www.hindawi.com/journals/omcl/2022/4619760/


The Effectiveness and Safety of Medical Cannabis for Treating Cancer Related Symptoms in Oncology Patients

Frontiers in Pain Research (@FrontPain) / Twitter

“The use of medical cannabis (MC) to treat cancer-related symptoms is rising. However, there is a lack of long-term trials to assess the benefits and safety of MC treatment in this population. In this work, we followed up prospectively and longitudinally on the effectiveness and safety of MC treatment.

Oncology patients reported on multiple symptoms before and after MC treatment initiation at one-, three-, and 6-month follow-ups. Oncologists reported on the patients’ disease characteristics. Intention-to-treat models were used to assess changes in outcomes from baseline. MC treatment was initiated by 324 patients and 212, 158 and 126 reported at follow-ups.

Most outcome measures improved significantly during MC treatment for most patients (p < 0.005). Specifically, at 6 months, total cancer symptoms burden declined from baseline by a median of 18%, from 122 (82–157) at baseline to 89 (45–138) at endpoint (−18.98; 95%CI= −26.95 to −11.00; p < 0.001). Reported adverse effects were common but mostly non-serious and remained stable during MC treatment.

The results of this study suggest that MC treatment is generally safe for oncology patients and can potentially reduce the burden of associated symptoms with no serious MC-related adverse effects.

The main finding of the current study is that most cancer comorbid symptoms improved significantly during 6 months of MC treatment.

Additionally, we found that MC treatment in cancer patients was well tolerated and safe.”

https://pubmed.ncbi.nlm.nih.gov/35669038/

https://www.frontiersin.org/articles/10.3389/fpain.2022.861037/full?utm_source=fweb

“Cancer Pain Treatment Using Marijuana Safe and Effective, Large Study Finds”

https://www.newsweek.com/cannabis-medicinal-cancer-patient-symptoms-pain-relief-1711981


The Endocannabinoid System as a Pharmacological Target for New Cancer Therapies

“Despite the long history of cannabinoid use for medicinal and ritual purposes, an endogenous system of cannabinoid-controlled receptors, as well as their ligands and the enzymes that synthesise and degrade them, was only discovered in the 1990s. Since then, the endocannabinoid system has attracted widespread scientific interest regarding new pharmacological targets in cancer treatment among other reasons.

Meanwhile, extensive preclinical studies have shown that cannabinoids have an inhibitory effect on tumour cell proliferation, tumour invasion, metastasis, angiogenesis, chemoresistance and epithelial-mesenchymal transition (EMT) and induce tumour cell apoptosis and autophagy as well as immune response. Appropriate cannabinoid compounds could moreover be useful for cancer patients as potential combination partners with other chemotherapeutic agents to increase their efficacy while reducing unwanted side effects.

In addition to the direct activation of cannabinoid receptors through the exogenous application of corresponding agonists, another strategy is to activate these receptors by increasing the endocannabinoid levels at the corresponding pathological hotspots. Indeed, a number of studies accordingly showed an inhibitory effect of blockers of the endocannabinoid-degrading enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) on tumour development and spread.

This review summarises the relevant preclinical studies with FAAH and MAGL inhibitors compared to studies with cannabinoids and provides an overview of the regulation of the endocannabinoid system in cancer.”

https://pubmed.ncbi.nlm.nih.gov/34830856/

“Cannabinoids have been shown to suppress tumour cell proliferation, tumour invasion, metastasis, angiogenesis, chemoresistance and epithelial-mesenchymal transition and to induce tumour cell apoptosis, autophagy and immune response. This review focuses on the current status of investigations on the impact of inhibitors of endocannabinoid-degrading enzymes on tumour growth and spread in preclinical oncology research.”

https://www.mdpi.com/2072-6694/13/22/5701


Plant-derived cannabinoids as anticancer agents

“Substantial preclinical evidence demonstrates the antiproliferative, cytotoxic, and antimetastatic properties of plant-derived cannabinoids (phytocannabinoids) such as cannabidiol and tetrahydrocannabinol. The cumulative body of research into the intracellular mechanisms and phenotypic effects of these compounds supports a logical, judicious progression to large-scale phase II/III clinical trials in certain cancer types to truly assess the efficacy of phytocannabinoids as anticancer agents.”

https://pubmed.ncbi.nlm.nih.gov/35260379/

Cannabinoids as anticancer drugs: current status of preclinical research

“Drugs that target the endocannabinoid system are of interest as pharmacological options to combat cancer and to improve the life quality of cancer patients. From this perspective, cannabinoid compounds have been successfully tested as a systemic therapeutic option in a number of preclinical models over the past decades. As a result of these efforts, a large body of data suggests that the anticancer effects of cannabinoids are exerted at multiple levels of tumour progression via different signal transduction mechanisms. Accordingly, there is considerable evidence for cannabinoid-mediated inhibition of tumour cell proliferation, tumour invasion and metastasis, angiogenesis and chemoresistance, as well as induction of apoptosis and autophagy. Further studies showed that cannabinoids could be potential combination partners for established chemotherapeutic agents or other therapeutic interventions in cancer treatment. Research in recent years has yielded several compounds that exert promising effects on tumour cells and tissues in addition to the psychoactive Δ9-tetrahydrocannabinol, such as the non-psychoactive phytocannabinoid cannabidiol and inhibitors of endocannabinoid degradation. This review provides an up-to-date overview of the potential of cannabinoids as inhibitors of tumour growth and spread as demonstrated in preclinical studies.”

https://pubmed.ncbi.nlm.nih.gov/35277658/

Cannabidiol and Other Phytocannabinoids as Cancer Therapeutics

“Preclinical models provided ample evidence that cannabinoids are cytotoxic against cancer cells. Among the best studied phytocannabinoids, cannabidiol (CBD) is most promising for the treatment of cancer as it lacks the psychotomimetic properties of delta-9-tetrahydrocannabinol (THC). In vitro studies and animal experiments point to a concentration- (dose-)dependent anticancer effect. The effectiveness of pure compounds versus extracts is the subject of an ongoing debate. Actual results demonstrate that CBD-rich hemp extracts must be distinguished from THC-rich cannabis preparations. Whereas pure CBD was superior to CBD-rich extracts in most in vitro experiments, the opposite was observed for pure THC and THC-rich extracts, although exceptions were noted. The cytotoxic effects of CBD, THC and extracts seem to depend not only on the nature of cannabinoids and the presence of other phytochemicals but also largely on the nature of cell lines and test conditions. Neither CBD nor THC are universally efficacious in reducing cancer cell viability. The combination of pure cannabinoids may have advantages over single agents, although the optimal ratio seems to depend on the nature of cancer cells; the existence of a ‘one size fits all’ ratio is very unlikely. As cannabinoids interfere with the endocannabinoid system (ECS), a better understanding of the circadian rhythmicity of the ECS, particularly endocannabinoids and receptors, as well as of the rhythmicity of biological processes related to the growth of cancer cells, could enhance the efficacy of a therapy with cannabinoids by optimization of the timing of the administration, as has already been reported for some of the canonical chemotherapeutics. Theoretically, a CBD dose administered at noon could increase the peak of anandamide and therefore the effects triggered by this agent. Despite the abundance of preclinical articles published over the last 2 decades, well-designed controlled clinical trials on CBD in cancer are still missing. The number of observations in cancer patients, paired with the anticancer activity repeatedly reported in preclinical in vitro and in vivo studies warrants serious scientific exploration moving forward.”

https://pubmed.ncbi.nlm.nih.gov/35244889/

Cannabis as a potential compound against various malignancies, legal aspects, advancement by exploiting nanotechnology and clinical trials

“Various preclinical and clinical studies exhibited the potential of cannabis against various diseases, including cancer and related pain. Subsequently, many efforts have been made to establish and develop cannabis-related products and make them available as prescription products. Moreover, FDA has already approved some cannabis-related products, and more advancement in this aspect is still going on. However, the approved product of cannabis is in oral dosage form, which exerts various limitations to achieve maximum therapeutic effects. A considerable translation is on a hike to improve bioavailability, and ultimately, the therapeutic efficacy of cannabis by the employment of nanotechnology. Besides the well-known psychotropic effects of cannabis upon the use at high doses, literature has also shown the importance of cannabis and its constituents in minimising the lethality of cancer in the preclinical models. This review discusses the history of cannabis, its legal aspect, safety profile, the mechanism by which cannabis combats with cancer, and the advancement of clinical therapy by exploiting nanotechnology. A brief discussion related to the role of cannabinoid in various cancers has also been incorporated. Lastly, the information regarding completed and ongoing trials have also been elaborated.”

https://pubmed.ncbi.nlm.nih.gov/35321629/

Effects of tetrahydrocannabinols on human oral cancer cell proliferation, apoptosis, autophagy, oxidative stress, and DNA damage

Archives of Oral Biology“Cannabinoids, including delta-8- and delta-9-tetrahydrocannabinol (THC) have a palliative care impact and may therefore be beneficial against cancer.

The aim of this study was to investigate the effect of Δ9-THC and Δ8-THC on oral cancer cell behaviors.

Results: Both cannabinoids were found to decrease cell viability/proliferation by blocking the cell cycle progression from the S to the G2/M phase and enhancing their apoptosis and autophagy. Δ9-THC and Δ8-THC also suppressed the migration/invasion by inhibiting epithelial-mesenchymal transition markers, such as E-cadherin, in addition to decreasing reactive oxygen species (ROS) production and increasing glutathione (GSH) and the expression of mtMP. Δ9-THC and Δ8-THC also downregulated cyclin D1, p53, NOXA, PUMAα, and DRAM expressions but increased p21 and H2AX expression.

Conclusion: We demonstrated that cannabinoids (Δ9-THC and Δ8-THC) were able to decrease oral cancer cell growth through various mechanisms, including apoptosis, autophagy, and oxidative stress. These results suggest a potential use of these molecules as a therapy against oral cancer.”

https://pubmed.ncbi.nlm.nih.gov/34146926/

Cannabinoids (Δ9-THC and Δ8-THC) decrease oral cancer cell viability/ proliferation.”

https://www.sciencedirect.com/science/article/abs/pii/S0003996921001631?via%3Dihub

Human laryngeal squamous cell carcinoma cell line release of endogenous anandamide and 2-arachidonoylglycerol, and their antiproliferative effect via exogenous supplementation: an in vitro study

SpringerLink“The level of the major endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are altered in several types of carcinomas, and are known to regulate tumor growth. Thusly, this study hypothesized that the HEp-2 human laryngeal squamous cell carcinoma (LSCC) cell line releases AEA and 2-AG, and aimed to determine if their exogenous supplementation has an anti-proliferative effect in vitro.

In this in vitro observational study a commercial human LSCC cell line (HEp-2) was used to test for endogenous AEA and 2-AG release via liquid chromatography-tandem mass spectrometry (LC-MS/MS). The anti-proliferative effect of AEA and 2-AG supplementation was evaluated via WST-1 proliferation assay. It was observed that the HEp-2 LSCC cell line released AEA and 2-AG; the median quantity of AEA released was 15.69 ng mL-1 (range: 14.55-15.95 ng mL-1) and the median quantity of 2-AG released was 2.72 ng -1 (range: 2.67-2.74 ng mL-1). Additionally, both AEA and 2-AG exhibited an anti-proliferative effect. The anti-proliferative effect of 2-AG was stronger than that of AEA. These findings suggest that AEA might function via a CB1 receptor-independent pathway and that 2-AG might function via a CB2-dependent pathway.

The present findings show that the HEp-2 LSCC cell line releases the major endocannabinoids AEA and 2-AG, and that their supplementation inhibits tumor cell proliferation in vitro. Thus, cannabinoid ligands might represent novel drug candidates for laryngeal cancers, although functional in vivo studies are required in order to validate their potency.”

https://pubmed.ncbi.nlm.nih.gov/33797678/

https://link.springer.com/article/10.1007/s10561-021-09917-9

Education and communication are critical to effectively incorporating cannabis into cancer treatment

“Providers need to be better equipped to discuss medical cannabis with patients even if they are not willing to prescribe it. The oncology community would be well served to ensure that providers are aware of existing cannabis research and are able to incorporate it into their communications with patients instead of leaving patients to figure out medical cannabis on their own.”

https://pubmed.ncbi.nlm.nih.gov/32986251/

https://acsjournals.onlinelibrary.wiley.com/doi/10.1002/cncr.33204