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/

Role of Caryophyllane Sesquiterpenes in the Entourage Effect of Felina 32 Hemp Inflorescence Phytocomplex in Triple Negative MDA-MB-468 Breast Cancer Cells

“Cannabis sativa L. crops have been traditionally exploited as sources of fibers, nutrients, and bioactive phytochemicals of medical interest. In the present study, two terpene-rich organic extracts, namely FOJ and FOS, obtained from Felina 32 hemp inflorescences collected in June and September, respectively, have been studied for their in vitro anticancer properties. Particularly, their cytotoxicity was evaluated in different cancer cell lines, and the possible entourage effect between nonintoxicating phytocannabinoids (cannabidiol and cannabichromene) and caryophyllane sesquiterpenes (β-caryophyllene, β-caryophyllene oxide and α-humulene), as identified at GC/MS analysis, was characterized. Modulation of cannabinoid CB1 and CB2 receptors was studied as a mechanistic hypothesis. Results highlighted marked cytotoxic effects of FOJ, FOS, and pure compounds in triple negative breast cancer MDA-MB-468 cells, likely mediated by a CB2 receptor activation. Cannabidiol was the main cytotoxic constituent, although low levels of caryophyllane sesquiterpenes and cannabichromene induced potentiating effects; the presence in the extracts of unknown antagonistic compounds has been highlighted too. These results suggest an interest in Felina 32 hemp inflorescences as a source of bioactive phytocomplexes with anticancer properties and strengthen the importance of considering the possible involvement of minor terpenes, such as caryophyllane sesquiterpenes, in the entourage effect of hemp-based extracts.”

https://pubmed.ncbi.nlm.nih.gov/34771097/


Cannabidiol Suppresses Angiogenesis and Stemness of Breast Cancer Cells by Downregulation of Hypoxia-Inducible Factors-1α

pubmed logo

“To assess the effect of Cannabidiol (CBD) on the angiogenesis and stemness of breast cancer cells as well as proliferation.

Methods: mRNA level and the amount of protein of vascular endothelial growth factor (VEGF) were determined by qRT-PCR and ELISA. The angiogenic potential of breast cancer cells under hypoxic conditions was identified by the HUVEC tube formation assay. The degradation of HIF-1α by CBD and the Src/von Hippel-Lindau tumor suppressor protein (VHL) interaction were assessed by a co-immunoprecipitation assay and Western blotting. To identify the stemness of mamospheres, they were evaluated by the sphere-forming assay and flow cytometry.

Results: CBD can suppress angiogenesis and stem cell-like properties of breast cancer through Src/VHL/HIF-1α signaling. CBD may potentially be utilized in the treatment of refractory or recurrent breast cancer.”

https://pubmed.ncbi.nlm.nih.gov/34830821/

Simple Summary

“Cannabidiol (CBD), one of the compounds present in the marijuana plant, has antitumor properties. However, the effect of CBD on breast cancer remains unclear. The aim of this study was to assess the effects of CBD for the angiogenesis and stemness of breast cancer cells by decreasing the expression of hypoxia-induced factor-1α (HIF-1α) through the Src/von Hippel–Lindau tumor suppressor protein (VHL) interaction. CBD can suppress angiogenesis and stem cell-like properties of breast cancer through Src/VHL/HIF-1α signaling.”

https://www.mdpi.com/2072-6694/13/22/5667


The Endocannabinoid System: A Potential Target for the Treatment of Various Diseases

ijms-logo“The Endocannabinoid System (ECS) is primarily responsible for maintaining homeostasis, a balance in internal environment (temperature, mood, and immune system) and energy input and output in living, biological systems.

In addition to regulating physiological processes, the ECS directly influences anxiety, feeding behaviour/appetite, emotional behaviour, depression, nervous functions, neurogenesis, neuroprotection, reward, cognition, learning, memory, pain sensation, fertility, pregnancy, and pre-and post-natal development.

The ECS is also involved in several pathophysiological diseases such as cancer, cardiovascular diseases, and neurodegenerative diseases. In recent years, genetic and pharmacological manipulation of the ECS has gained significant interest in medicine, research, and drug discovery and development.

The distribution of the components of the ECS system throughout the body, and the physiological/pathophysiological role of the ECS-signalling pathways in many diseases, all offer promising opportunities for the development of novel cannabinergic, cannabimimetic, and cannabinoid-based therapeutic drugs that genetically or pharmacologically modulate the ECS via inhibition of metabolic pathways and/or agonism or antagonism of the receptors of the ECS. This modulation results in the differential expression/activity of the components of the ECS that may be beneficial in the treatment of a number of diseases.

This manuscript in-depth review will investigate the potential of the ECS in the treatment of various diseases, and to put forth the suggestion that many of these secondary metabolites of Cannabis sativa L. (hereafter referred to as “C. sativa L.” or “medical cannabis”), may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases.”

https://pubmed.ncbi.nlm.nih.gov/34502379/

https://www.mdpi.com/1422-0067/22/17/9472

 

“Cannabis sativa L. as a Natural Drug Meeting the Criteria of a Multitarget Approach to Treatment”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830475/

Cannabidiol Loaded Extracellular Vesicles Sensitize Triple-Negative Breast Cancer to Doxorubicin in both in-vitro and in vivo Models Running Title: Formulation and anti-cancer potential of CBD loaded hUCMSC-derived Extracellular Vesicles in TNBC

International Journal of Pharmaceutics“Extracellular Vesicles (EVs) were isolated from human umbilical cord mesenchymal stem cells (hUCMSCs) and were further encapsulated with cannabidiol (CBD) through sonication method (CBD EVs). CBD EVs displayed an average particle size of 114.1±1.02 nm, zeta potential of -30.26±0.12 mV, entrapment efficiency of 92.3±2.21% and stability for several months at 4 °C. CBD release from the EVs was observed as 50.74±2.44% and 53.99±1.4% at pH 6.8 and pH 7.4, respectively after 48 h. Ourin-vitrostudies demonstrated that CBD either alone or in EVs form significantly sensitized MDA-MB-231 cells to doxorubicin (DOX) (*P<0.05). Flow cytometry and migration studies revealed that CBD EVs either alone or in combination with DOX induced G1 phase cell cycle arrest and decreased migration of MDA-MB-231 cells, respectively. CBD EVs and DOX combination significantly reduced tumor burden (***P<0.001) in MDA-MB-231 xenograft tumor model. Western blotting and immunocytochemical analysis demonstrated that CBD EVs and DOX combination decreased the expression of proteins involved in inflammation, metastasis and increased the expression of proteins involved in apoptosis. CBD EVs and DOX combination will have profound clinical significance in not only decreasing the side effects but also increasing the therapeutic efficacy of DOX in TNBC.”

https://pubmed.ncbi.nlm.nih.gov/34324983/

https://www.sciencedirect.com/science/article/abs/pii/S0378517321007493?via%3Dihub

Cancer Initiation, Progression and Resistance: Are Phytocannabinoids from Cannabis sativa L. Promising Compounds?

molecules-logo“Cannabis sativa L. is a source of over 150 active compounds known as phytocannabinoids that are receiving renewed interest due to their diverse pharmacologic activities. Indeed, phytocannabinoids mimic the endogenous bioactive endocannabinoids effects through activation of CB1 and CB2 receptors widely described in the central nervous system and peripheral tissues.

All phytocannabinoids have been studied for their protective actions towards different biological mechanisms, including inflammation, immune response, oxidative stress that, altogether, result in an inhibitory activity against the carcinogenesis.

The role of the endocannabinoid system is not yet completely clear in cancer, but several studies indicate that cannabinoid receptors and endogenous ligands are overexpressed in different tumor tissues.

Recently, in vitro and in vivo evidence support the effectiveness of phytocannabinoids against various cancer types, in terms of proliferation, metastasis, and angiogenesis, actions partially due to their ability to regulate signaling pathways critical for cell growth and survival.

The aim of this review was to report the current knowledge about the action of phytocannabinoids from Cannabis sativa L. against cancer initiation and progression with a specific regard to brain, breast, colorectal, and lung cancer as well as their possible use in the therapies. We will also report the known molecular mechanisms responsible for such positive effects.

Finally, we will describe the actual therapeutic options for Cannabis sativa L. and the ongoing clinical trials.”

https://pubmed.ncbi.nlm.nih.gov/34063214/

https://www.mdpi.com/1420-3049/26/9/2668