Active Component Of Marijuana Has Anti-Cancer Effects, Study Suggests

“Guillermo Velasco and colleagues, at Complutense University, Spain, have provided evidence that suggests that cannabinoids such as the main active component of marijuana (THC) have anticancer effects on human brain cancer cells.

In the study, THC was found to induce the death of various human brain cancer cell lines and primary cultured human brain cancer cells by a process known as autophagy.

Consistent with the in vitro data, administration of THC to mice with human tumors decreased tumor growth and induced the tumor cells to undergo autophagy. As analysis of tumors from two patients with recurrent glioblastoma multiforme (a highly aggressive brain tumor) receiving intracranial THC administration showed signs of autophagy, the authors suggest that cannabinoid administration may provide a new approach to targeting human cancers.”  http://www.sciencedaily.com/releases/2009/04/090401181217.htm

“Cannabinoid action induces autophagy-mediated cell death through stimulation of ER stress in human glioma cells” https://www.jci.org/articles/view/37948

 

Antitumor Effects of THC.

“1-Trans-[delta.sup.9]-tetrahydrocannabinol (THC) the main active component of marijuana, has been shown to exhibit anticancer activity.

Galve-Roperh et al. reported that intratumoral administration of THC induces apoptosis of transformed neural cells in culture, and also induces a considerable regression of malignant gliomas in Wistar rats and in mice… These authors suggest that their “results may provide the basis for a new therapeutic approach for the treatment of malignant gliomas.”

Thus, in our studies, rats and mice that received THC for 2 years exhibited body weight reductions, enhanced survival rates, and decreased tumor incidences in several sites, mainly organs under hormonal control.

These earlier experimental carcinogenesis results on THC clearly lend further validity to the notion that cannabinoids may indeed be anticarcinogenic.”

http://www.thefreelibrary.com/Antitumor+Effects+of+THC.-a068148345

“Antitumor effects of THC.” http://www.ncbi.nlm.nih.gov/pubmed/11097557

Local Delivery of Cannabinoid-Loaded Microparticles Inhibits Tumor Growth in a Murine Xenograft Model of Glioblastoma Multiforme

“Treatment with cannabinoid-loaded microparticles activates apoptosis and inhibits tumor angiogensis. The aim of the present study was therefore to evaluate the antitumor efficacy of biodegradable polymeric microparticles allowing the controlled release of the phytocannabinoids THC and CBD. Our findings show that administration of cannabinoid-loaded microparticles reduces the growth of glioma xenografts supporting that this method of administration could be exploited for the design of cannabinoid-based anticancer treatments.

Cannabinoids, the active components of marijuana and their derivatives, are currently investigated due to their potential therapeutic application for the management of many different diseases, including cancer. Specifically, Δ9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD) – the two major ingredients of marijuana – have been shown to inhibit tumor growth in a number of animal models of cancer, including glioma. Although there are several pharmaceutical preparations that permit the oral administration of THC or its analogue nabilone or the oromucosal delivery of a THC- and CBD-enriched cannabis extract, the systemic administration of cannabinoids has several limitations in part derived from the high lipophilicity exhibited by these compounds. In this work we analyzed CBD- and THC-loaded poly-ε-caprolactone microparticles as an alternative delivery system for long-term cannabinoid administration in a murine xenograft model of glioma. In vitro characterization of THC- and CBD-loaded microparticles showed that this method of microencapsulation facilitates a sustained release of the two cannabinoids for several days. Local administration of THC-, CBD- or a mixture (1:1 w:w) of THC- and CBD-loaded microparticles every 5 days to mice bearing glioma xenografts reduced tumour growth with the same efficacy than a daily local administration of the equivalent amount of those cannabinoids in solution. Moreover, treatment with cannabinoid-loaded microparticles enhanced apoptosis and decreased cell proliferation and angiogenesis in these tumours. Our findings support that THC- and CBD-loaded microparticles could be used as an alternative method of cannabinoid delivery in anticancer therapies.

Δ9-Tetrahydrocannabinol (THC), the main active component of the hemp plant Cannabis sativa, exerts a wide variety of biological effects by mimicking endogenous substances – the endocannabinoids – that bind to and activate specific cannabinoid receptors. So far, two G protein–coupled cannabinoid-specific receptors have been cloned and characterized from mammalian tissues: CB1, abundantly expressed in the brain and at many peripheral sites, and CB2, expressed in the immune system and also present in some neuron subpopulations and glioma cells. One of the most active areas of research in the cannabinoid field is the study of the potential application of cannabinoids in the treatment of different pathologies. Among these therapeutic applications, cannabinoids are being investigated as anti-tumoral agents. Thus, cannabinoid administration curbs the growth of several types of tumor xenografts in rats and mice including gliomas. Based on this preclinical evidence, a pilot clinical trial has been recently run to investigate the anti-tumor action of THC on recurrent gliomas. The mechanism of THC anti-tumoral action relies on the ability of this compound to: (i) promote the apoptotic death of cancer cells (ii) to inhibit tumour angiogenesis and (iii) to reduce the migration of cancer cells.

Conclusions

Data presented in this manuscript show for the first time that in vivo administration of microencapsulated cannabinoids efficiently reduces tumor growth thus providing a proof of concept for the utilization of this formulation in cannabinoid-based anti-cancer therapies.”

Full text: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0054795. 

Cannabinoids for Cancer Treatment: Progress and Promise

Cancer Research: 68 (2)

“Cannabinoid refers to a group of chemicals naturally found in the marijuana plant Cannabis sativa L. and includes compounds that are either structurally or pharmacologically similar to Δ(9)-tetrahydrocannabinol or those that bind to the cannabinoid receptors. Although anticancer effects of cannabinoids were shown as early as 1975 in Lewis lung carcinoma, renewed interest was generated little after the discovery of the cannabinoid system and cloning of the specific cannabinoid receptors.

Cannabinoids are a class of pharmacologic compounds that offer potential applications as antitumor drugs, based on the ability of some members of this class to limit inflammation, cell proliferation, and cell survival. In particular, emerging evidence suggests that agonists of cannabinoid receptors expressed by tumor cells may offer a novel strategy to treat cancer. Here, we review recent work that raises interest in the development and exploration of potent, nontoxic, and nonhabit forming cannabinoids for cancer therapy.”

Full Text: http://cancerres.aacrjournals.org/content/68/2/339.long

Cannabinoids Halt Pancreatic Cancer, Breast Cancer Growth, Studies Say

“Compounds in cannabis inhibit cancer cell growth in human breast cancer cell lines and in pancreatic tumor cell lines, according to a pair of preclinical trials published in the July issue of the journal of the American Association for Cancer Research.

In one trial, investigators at Complutense University in Spain and the Institut National de la Sante et de la Recherche Medicale (INSERM) in France assessed the anti-cancer activity of cannabinoids in pancreatic cancer cell lines and in animals. Cannabinoid administration selectively increased apoptosis (programmed cell death) in pancreatic tumor cells while ignoring healthy cells, researchers found. In addition, “cannabinoid treatment inhibited the spreading of pancreatic tumor cells … and reduced the growth of tumor cells” in animals.

“These findings may contribute to … a new therapeutic approach for the treatment of pancreatic cancer,” authors concluded.

In the second trial, investigators at Spain’s Complutense University reported that THC administration “reduces human breast cancer cell proliferation [in vitro] by blocking the progression of the cell cycle and by inducing apoptosis.” Authors concluded that their findings “may set the bases for a cannabinoid therapy for the management of breast cancer.”

Previous preclinical data published in May in the Journal of Pharmacological and Experimental Therapeutics reported that non-psychoactive cannabinoids, particularly cannabidiol (CBD), dramatically halt the spread of breast cancer cells and recommended their use in cancer therapy.

Separate trials have also shown cannabinoids to reduce the size and halt the spread of glioma (brain tumor) cells in animals and humans in a dose dependent manner. Additional preclinical studies have demonstrated cannabinoids to inhibit cancer cell growth and selectively trigger malignant cell death in skin cancer cells, leukemic cells, lung cancer cells, and prostate carcinoma cells, among other cancerous cell lines.”

http://norml.org/news/2006/07/06/cannabinoids-halt-pancreatic-cancer-breast-cancer-growth-studies-say

Pot Compound Reduces Anxiety

“According to clinical trial data published online in The Journal of Psychopharmacology, the administration of the non-psychoactive component of marijuana [cannabinoid cannabidiol (CBD)] reduces anxiety in subjects with social anxiety disorder (SAD).

The anti-anxiety activity of oral doses of CBD in ten subjects was assessed by investigators at the University of Sao Paulo in Brazil in a double blind, placebo-controlled trial.

Researchers concluded, “CBD reduces anxiety in SAD and that this is related to its effects on activity in limbic and paralimbic brain areas.”

This study is the first clinical trial to investigate the effects of cannabinoid cannabidiol on human pathological anxiety and its underlying brain mechanisms.

Previous studies in the context of CBD have suggested that the compound possesses anti-inflammatory activity, anti-cancer activity, and neuroprotective effects – among other therapeutic properties.

The study “Neural basis of anxiolytic effects of cannabidiol (CBD) in generalized social anxiety disorder: a preliminary report,” appeared online in The Journal of Psychopharmacology.”

http://www.imarijuana.com/news/pot-compound-reduces-anxiety

The Cannabinoid CB2 Receptor as a Target for Inflammation-Dependent Neurodegeneration

“THE CANNABINOID CB2 RECEPTOR AS A BIORATIONAL TARGET FOR THE TREATMENT OF NEURODEGENERATION. The presence of CB2 receptors in microglia in the human Alzheimer’s diseased brain suggests that CB2 may provide a novel target for a range of neuropathologies.

 The first approved cannabinoid drugs were analogues of Δ9-tetrahydrocannabinol (Δ9-THC). Dronabinol is a natural isomer of THC that is found in the cannabis plant, and Marinol™ contains synthetic dronabinol. Marinol, and another analogue nabilone (Cesamet™ ) are used to prevent nausea and vomiting after treatment with anti-cancer medicines. More recently, GW-100 (Sativex™) which combines nearly equal amounts of Δ9-THC and cannabidiol in a whole plant extract from cultivated cannabis, has been approved in Canada…

We conclude that the administration of CB2 agonists and antagonists may differentially alter microglia-dependent neuroinflammation. CB2 specific compounds have considerable therapeutic appeal over CB1 compounds, as the exclusive expression of CB2 on immune cells within the brain provides a highly specialised target, without the psychoactivity that plagues CB1 directed therapies.

In addition, CB2 activation appears to prevent or decrease microglial activation.

In a rodent model of Alzheimer’s disease microglial activation was completely prevented by administration of a selective CB2 agonist.”

http://www.ncbi.nlm.nih.gov/pubmed/18615177

Cannabinoids and omega-3/6 endocannabinoids as cell death and anticancer modulators.

Cover image

“Cannabinoids-endocannaboids are possible preventatives of common diseases including cancers. Cannabinoid receptors (CB(½), TRPV1) are central components of the system. Many disease-ameliorating effects of cannabinoids-endocannabinoids are receptor mediated, but many are not, indicating non-CBR signaling pathways.

Cannabinoids-endocannabinoids are anti-inflammatory, anti-proliferative, anti-invasive, anti-metastatic and pro-apoptotic in most cancers, in vitro and in vivo in animals.

They signal through p38, MAPK, JUN, PI3, AKT, ceramide, caspases, MMPs, PPARs, VEGF, NF-κB, p8, CHOP, TRB3 and pro-apoptotic oncogenes (p53,p21 waf1/cip1) to induce cell cycle arrest, autophagy, apoptosis and tumour inhibition. Paradoxically they are pro-proliferative and anti-apoptotic in some cancers. Differences in receptor expression and concentrations of cannabinoids in cancer and immune cells can elicit anti- or pro-cancer effects through different signal cascades (p38MAPK or PI3/AKT).

Similarities between effects of cannabinoids-endocannabinoids, omega-3 LCPUFA and CLAs/CLnAs as anti-inflammatory, antiangiogenic, anti-invasive anti-cancer agents indicate common signaling pathways.

Evidence in vivo and in vitro shows EPA and DHA can form endocannabinoids that: (i) are ligands for CB(½) receptors and possibly TRPV-1, (ii) have non-receptor mediated bioactivity, (iii) induce cell cycle arrest, (iii) increase autophagy and apoptosis, and (iv) augment chemotherapeutic actions in vitro. They can also form bioactive, eicosanoid-like products that appear to be non-CBR ligands but have effects on PPARs and NF-kB transcription factors. The use of cannabinoids in cancer treatment is currently limited to chemo- and radio-therapy-associated nausea and cancer-associated pain apart from one trial on brain tumours in patients. Further clinical studies are urgently required to determine the true potential of these intriguing, low toxicity compounds in cancer therapy. Particularly in view of their synergistic effects with chemotherapeutic agents similar to that observed for n-3 LCPUFA.”  https://www.ncbi.nlm.nih.gov/pubmed/23103355

http://www.sciencedirect.com/science/article/pii/S0163782712000537

Therapeutic Potential of Monoacylglycerol Lipase Inhibitors.

Abstract

 “Marijuana and aspirin have been used for millennia to treat a wide range of maladies including pain and inflammation. Both cannabinoids, like marijuana, that exert anti-inflammatory action through stimulating cannabinoid receptors, and cyclooxygenase (COX) inhibitors, like aspirin, that suppress pro-inflammatory eicosanoid production have shown benefitial outcomes in mouse models of neurodegenerative diseases and cancer. Both cannabinoids and COX inhibitors, however, have untoward effects that discourage their chronic usage, including cognitive deficits and gastrointestinal toxicity, respectively. Recent studies have uncovered that the serine hydrolase monoacylglycerol lipase (MAGL) links the endocannabinoid and eicosanoid systems together through hydrolysis of the endocannabinoid 2-arachidonoylglycerol (2-AG) to provide the major arachidonic acid (AA) precursor pools for pro-inflammatory eicosanoid synthesis in specific tissues. Studies in recent years have shown that MAGL inhibitors elicit anti-nociceptive, anxiolytic, and anti-emetic responses and attenuate precipitated withdrawal symptoms in addiction paradigms through enhancing endocannabinoid signaling. MAGL inhibitors have also been shown to exert anti-inflammatory action in the brain and protect against neurodegeneration through lowering eicosanoid production. In cancer, MAGL inhibitors have been shown to have anti-cancer properties not only through modulating the endocannabinoid-eicosanoid network, but also by controlling fatty acid release for the synthesis of protumorigenic signaling lipids. Thus, MAGL serves as a critical node in simultaneously coordinating multiple lipid signaling pathways in both physiological and disease contexts. This review will discuss the diverse (patho)physiological roles of MAGL and the therapeutic potential of MAGL inhibitors in treating a vast array of complex human diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/23142242

A new strategy to block tumor growth by inhibiting endocannabinoid inactivation.

Image result for faseb journal

“Endocannabinoid signaling has been shown to be enhanced in several cancer tissues and malignant cells, and studies in cell lines have shown that this up-regulation might serve the purpose of providing transformed cells with a further means to inhibit their proliferation. Here we investigated the effect of inhibitors of endocannabinoid degradation on the growth of rat thyroid tumor xenografts induced in athymic mice. VDM-11, a selective inhibitor of endocannabinoid cellular re-uptake, and arachidonoyl-serotonin (AA-5-HT), a selective blocker of endocannabinoid enzymatic hydrolysis, both inhibited the growth in vivo of tumor xenografts induced by the subcutaneous injection of rat thyroid transformed (KiMol) cells. This effect was accompanied by significantly enhanced endocannabinoid concentrations in the tumors excised at the end of the in vivo experiments. Endocannabinoids, as well as VDM-11 and AA-5-HT, inhibited the growth in vitro of the transformed rat thyroid cells used to induce the tumors in vivo, and their effect was reversed at least in part by the cannabinoid CB1 receptor antagonist SR141716A. This compound, however, when administered alone, did not enhance, but instead slightly inhibited, the growth of rat thyroid transformed cells both in vitro and in tumor xenografts induced in vivo. These findings indicate that endocannabinoids tonically control tumor growth in vivo by both CB1-mediated and non-CB1-mediated mechanisms and that, irrespective of the molecular mechanism of their anti-proliferative action, inhibitors of their inactivation might be used for the development of novel anti-cancer drugs.”  http://www.ncbi.nlm.nih.gov/pubmed/15289448

“A new strategy to block tumor growth by inhibiting endocannabinoid inactivation”  http://www.fasebj.org/content/early/2004/10/02/fj.04-1754fje.long