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/

Cannabis sativa Extract Induces Apoptosis in Human Pancreatic 3D Cancer Models: Importance of Major Antioxidant Molecules Present Therein

“In recent years, interest in Cannabis sativa L. has been rising, as legislation is moving in the right direction. This plant has been known and used for thousands of years for its many active ingredients that lead to various therapeutic effects (pain management, anti-inflammatory, antioxidant, etc.). In this report, our objective was to optimize a method for the extraction of cannabinoids from a clone of Cannabis sativa L. #138 resulting from an agronomic test (LaFleur, Angers, FR). Thus, we wished to identify compounds with anticancer activity on human pancreatic tumor cell lines. Three static maceration procedures, with different extraction parameters, were compared based on their median inhibitory concentration (IC50) values and cannabinoid extraction yield. As CBD emerged as the molecule responsible for inducing apoptosis in the human pancreatic cancer cell line, a CBD-rich cannabis strain remains attractive for therapeutic applications. Additionally, while gemcitabine, a gold standard drug in the treatment of pancreatic cancer, only triggers cell cycle arrest in G0/G1, CBD also activates the cell signaling cascade to lead to programmed cell death. Our results emphasize the potential of natural products issued from medicinal hemp for pancreatic cancer therapy, as they lead to an accumulation of intracellular superoxide ions, affect the mitochondrial membrane potential, induce G1 cell cycle arrest, and ultimately drive the pancreatic cancer cell to lethal apoptosis.”

https://pubmed.ncbi.nlm.nih.gov/35209003/

Targeting the Endocannabinoid System: From the Need for New Therapies to the Development of a Promising Strategy. What About Pancreatic Cancer?

“Pancreatic cancer is one of the most fatal malignancies, and therefore, new strategies, which aim at the improvement of the prognosis of this lethal disease, are needed. Many clinical trials have failed to improve overall survival. Nowadays, research is focused on advances provided by novel potential targets to efficiently enhance life expectancy. Cannabinoids, the active components of Cannabis sativa L., and their derivatives, have been reported as palliative adjuvants to conventional chemotherapeutic regimens. Cannabinoid effects are known to be mediated through the activation of cannabinoid receptors. To date, two cannabinoid receptors, cannabinoid receptor 1 and 2, have been cloned and identified from mammalian tissues. Cannabinoids exert a remarkable antitumoral effect on pancreatic cancer cells, due to their ability to selectively induce apoptosis of these cells. This review strengthens the perception that cannabinoid receptors might be useful in clinical testing to prognose and treat pancreatic cancer. Many studies have tried to describe the mechanism of cell death induced by cannabinoids. The aim of this review is to discuss the effects of cannabinoid receptors in pancreatic cancer in order to provide a brief insight into cannabinoids and their receptors as pancreatic cancer biomarkers and in therapeutic strategies.”

https://pubmed.ncbi.nlm.nih.gov/35241505/

Targeting the Endocannabinoidome in Pancreatic Cancer

“Pancreatic Ductal adenocarcinoma (PDAC), the most common malignancy of the pancreas, is an aggressive and lethal form of cancer with a very high mortality rate. High heterogeneity, asymptomatic initial stages and a lack of specific diagnostic markers result in an end-stage diagnosis when the tumour has locally advanced or metastasised. PDAC is resistant to most of the available chemotherapy and radiation therapy treatments, making surgery the most potent curative treatment. The desmoplastic tumour microenvironment contributes to determining PDAC pathophysiology, immune response and therapeutic efficacy. The existing therapeutic approaches such as FDA-approved chemotherapeutics, gemcitabine, abraxane and folfirinox, prolong survival marginally and are accompanied by adverse effects. Several studies suggest the role of cannabinoids as anti-cancer agents. Cannabinoid receptors are known to be expressed in pancreatic cells, with a higher expression reported in pancreatic cancer patients. Therefore, pharmacological targeting of the endocannabinoid system might offer therapeutic benefits in pancreatic cancer. In addition, emerging data suggest that cannabinoids in combination with chemotherapy can increase survival in transgenic pancreatic cancer murine models. This review provides an overview of the regulation of the expanded endocannabinoid system, or endocannabinoidome, in PDAC and will explore the potential of targeting this system for novel anticancer approaches.”

https://pubmed.ncbi.nlm.nih.gov/35204820/

Cannabis and its Constituents for Cancer: History, Biogenesis, Chemistry and Pharmacological Activities

Pharmacological Research “Cannabis has long been used for healing and recreation in several regions of the world. Over 400 bioactive constituents, including more than 100 phytocannabinoids, have been isolated from this plant. The non-psychoactive cannabidiol (CBD) and the psychoactive Δ9-tetrahydrocannabinol (Δ9-THC) are the major and widely studied constituents from this plant.

Cannabinoids exert their effects through the endocannabinoid system (ECS) that comprises cannabinoid receptors (CB1, CB2), endogenous ligands, and metabolizing enzymes. Several preclinical studies have demonstrated the potential of cannabinoids against leukemia, lymphoma, glioblastoma, and cancers of the breast, colorectum, pancreas, cervix and prostate.

Cannabis and its constituents can modulate multiple cancer related pathways such as PKB, AMPK, CAMKK-β, mTOR, PDHK, HIF-1α, and PPAR-γ. Cannabinoids can block cell growth, progression of cell cycle and induce apoptosis selectively in tumour cells. Cannabinoids can also enhance the efficacy of cancer therapeutics. These compounds have been used for the management of anorexia, queasiness, and pain in cancer patients.

Cannabinoid based products such as dronabinol, nabilone, nabiximols, and epidyolex are now approved for medical use in cancer patients. Cannabinoids are reported to produce a favourable safety profile. However, psychoactive properties and poor bioavailability limit the use of some cannabinoids. The Academic Institutions across the globe are offering training courses on cannabis. How cannabis and its constituents exert anticancer activities is discussed in this article. We also discuss areas that require attention and more extensive research.”

https://pubmed.ncbi.nlm.nih.gov/33246167/

https://www.sciencedirect.com/science/article/abs/pii/S1043661820316108?via%3Dihub

Cannabinoids Inhibited Pancreatic Cancer via P-21 Activated Kinase 1 Mediated Pathway

ijms-logo“The anti-cancer effects of cannabinoids including CBD (Cannabidiol) and THC ((-)-trans-∆9-tetrahydrocannabinol) have been reported in the case of pancreatic cancer (PC).

The connection of these cannabinoids to KRas oncogenes that mutate in more than 90% of PC, and their effects on PD-L1, a key target of immune checkpoint blockade, have not been thoroughly investigated. Using cell lines and mouse models of PC, the effects of CBD and THC on cancer growth, the interaction between PC cells and a stromal cell, namely pancreatic stellate cells (PSCs), and the mechanism(s) involved were determined by cell-based assays and mouse study in vivo.

CBD and THC inhibited the proliferation of PC, PSC, and PSC-stimulated PC cells. They also suppressed pancreatic tumour growth in mice. Furthermore, CBD and/or THC reduced the expression of PD-L1 by either PC or PSC cells. Knockout of p-21 activated kinase 1 (PAK1, activated by KRas) in PC and PSC cells and, in mice, dramatically decreased or blocked these inhibitory effects of CBD and/or THC.

These results indicated that CBD and THC exerted their inhibitions on PC and PSC via a p-21 activated kinase 1 (PAK1)-dependent pathway, suggesting that CBD and THC suppress Kras activated pathway by targeting PAK1. The inhibition by CBD and THC of PD-L1 expression will enhance the immune checkpoint blockade of PC.”

https://pubmed.ncbi.nlm.nih.gov/33126623/

https://www.mdpi.com/1422-0067/21/21/8035

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

Cancer patients’ experiences with medicinal cannabis-related care

 “Background: Little is known about medical cannabis (MC)-related care for patients with cancer using MC.

Methods: Semistructured telephone interviews were conducted in a convenience sample of individuals (n = 24) with physician-confirmed oncologic diagnoses and state/district authorization to use MC (Arizona, California, Florida, Illinois, Massachusetts, Oregon, New York, and Washington, DC) from April 2017 to March 2019. Standard qualitative techniques were used to assess the degree of MC-related health care oversight, MC practices, and key information sources.

Results: Among 24 participants (median age, 57 years; range, 30-71 years; 16 women [67%]), MC certifications were typically issued by a professional new to a patient’s care after a brief, perfunctory consultation. Patients disclosed MCuse to their established medical teams but received little medical advice about whether and how to use MC. Patients with cancer used MC products as multipurpose symptom management and as cancer-directed therapy, sometimes in lieu of standard-of-care treatments. Personal experimentation, including methodical self-monitoring, was an important source of MC know-how. Absent formal advice from medical professionals, patients relied on nonmedical sources for MC information.

Conclusions: Patients with cancer used MC with minimal medical oversight. Most received MC certifications through brief meetings with unfamiliar professionals. Participants desired but were often unable to access high-quality clinical information about MC from their established medical teams. Because many patients are committed to using MC, a product sustained by a growing industry, medical providers should familiarize themselves with the existing data for MM and its limitations to address a poorly met clinical need.”

https://pubmed.ncbi.nlm.nih.gov/32986266/

“Notably, oncology patients reported using medical cannabis (MC) for symptom management and as cancer‐directed therapy, sometimes instead of traditional treatments.”

https://acsjournals.onlinelibrary.wiley.com/doi/10.1002/cncr.33202