Endocannabinoids as emerging suppressors of angiogenesis and tumor invasion (review).

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“The medicinal properties of extracts from the hemp plant Cannabis sativa have been known for centuries but only in the 90s membrane receptors for the Cannabis major principle were discovered in mammalian cells. Later on the endogenous ligands for the cannabinoid receptors were identified and the term ‘endocannabinoid system’ was coined to indicate the complex signaling system of cannabinoid receptors, endogenous ligands and the enzymes responsible for their biosynthesis and inactivation.

The ‘endocannabinoid system’ is involved in a broad range of functions and in a growing number of pathological conditions.

There is increasing evidence that endocannabinoids are able to inhibit cancer cell growth in culture as well as in animal models.

Most work has focused on the role of endocannabinoids in regulating tumor cell growth and apoptosis and ongoing research is addressed to further dissect the precise mechanisms of cannabinoid antitumor action. However, endocannabinoids are now emerging as suppressors of angiogenesis and tumor spreading since they have been reported to inhibit angiogenesis, cell migration and metastasis in different types of cancer, pointing to a potential role of the endocannabinoid system as a target for a therapeutic approach of such malignant diseases.

The potential use of cannabinoids to retard tumor growth and spreading is even more appealing considering that they show a good safety profile, regarding toxicity, and are already used in cancer patients as palliatives to stimulate appetite and to prevent devastating effects such as nausea, vomiting and pain.”  http://www.ncbi.nlm.nih.gov/pubmed/17342320

https://www.spandidos-publications.com/or/17/4/813

Cannabinoid-associated cell death mechanisms in tumor models

“In recent years, cannabinoids (the active components of Cannabis sativa) and their derivatives have received considerable interest due to findings that they can affect the viability and invasiveness of a variety of different cancer cells. Moreover, in addition to their inhibitory effects on tumor growth and migration, angiogenesis and metastasis, the ability of these compounds to induce different pathways of cell death has been highlighted. Here, we review the most recent results generating interest in the field of death mechanisms induced by cannabinoids in cancer cells. In particular, we analyze the pathways triggered by cannabinoids to induce apoptosis or autophagy and investigate the interplay between the two processes. Overall, the results reported here suggest that the exploration of molecular mechanisms induced by cannabinoids in cancer cells can contribute to the development of safe and effective treatments in cancer therapy.”

http://www.ncbi.nlm.nih.gov/pubmed/22614735

The endocannabinoid system in the cancer therapy: an overview.

“The endocannabinoid system comprises the cannabinoid receptors type 1 (CB1) and type 2 (CB2), their endogenous ligands (endocannabinoids), and the proteins responsible for their biosynthesis and degradation. This ubiquitous signalling system, that has attracted a great deal of scientist interest in the past 15 years, regulates several physiological and pathological functions. In mammals, among other functions, the endocannabinoid is involved in nervous, cardiovascular, metabolic, reproductive and immune functions. Finally, yet importantly, endocannabinoids are known to exert important antiproliferative actions in a great number of tumor cells including breast, brain, skin, thyroid, prostate and colorectal. The following review describes our current knowledge on the effects of two of the most studied endocannabinoids (AEA and 2-AG) on various types of tumor and summarizes the possible mechanism of observed antitumor effects.”  http://www.ncbi.nlm.nih.gov/pubmed/21428888

http://www.eurekaselect.com/73874/article

The endocannabinoid system and cancer: therapeutic implication

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“The endocannabinoid system is implicated in a variety of physiological and pathological conditions (inflammation, immunomodulation, analgesia, cancer and others).

The main active ingredient of cannabis, Δ(9) -tetrahydrocannabinol (Δ(9) -THC), produces its effects through activation of CB(1) and CB(2) receptors. CB(1) receptors are expressed at high levels in the central nervous system (CNS), whereas CB(2) receptors are concentrated predominantly, although not exclusively, in cells of the immune system.

Endocannabinoids are endogenous lipid-signalling molecules that are generated in the cell membrane from phospholipid precursors. The two best characterized endocannabinoids identified to date are anandamide (AEA) and 2-arachidonoylglycerol (2-AG). Here we review the relationship between the endocannabinoid system and anti-tumour actions (inhibition of cell proliferation and migration, induction of apoptosis, reduction of tumour growth) of the cannabinoids in different types of cancer.

This review will focus on examining how activation of the endocannabinoid system impacts breast, prostate and bone cancers in both in vitro and in vivo systems. The therapeutic potential of cannabinoids for cancer, as identified in clinical trials, is also discussed.

Identification of safe and effective treatments to manage and improve cancer therapy is critical to improve quality of life and reduce unnecessary suffering in cancer patients. In this regard, cannabis-like compounds offer therapeutic potential for the treatment of breast, prostate and bone cancer in patients.

Further basic research on anti-cancer properties of cannabinoids as well as clinical trials of cannabinoid therapeutic efficacy in breast, prostate and bone cancer is therefore warranted.” http://www.ncbi.nlm.nih.gov/pubmed/21410463

“The available literature suggests that the endocannabinoid system may be targeted to suppress the evolution and progression of breast, prostate and bone cancer as well as the accompanying pain syndromes. Many in vitro and in vivo studies have shown that cannabinoids are efficacious in reducing cancer progression (i.e. inhibition of tumour growth and metastases as well as induction of apoptosis and other anti-cancer properties) in breast, prostate and bone cancer. Although this review focuses on these three types of cancer, activation of the endocannabinoid signalling system produces anti-cancer effects in other types of cancer.” http://onlinelibrary.wiley.com/doi/10.1111/j.1476-5381.2011.01327.x/full

Cannabinoid receptor activation correlates with the pro-apoptotic action of the β2-adrenergic agonist, (R,R’)-4-methoxy-1-naphthylfenoterol, in HepG2 hepatocarcinoma cells

“In the last several years, development of new CBR ligands has become an intense area in cancer research because of the role of the endocannabinoid system in the regulation of cell proliferation and apoptosis…

The therapeutic potential for synthetic small bivalent ligands holds great promise as new lead compounds in a wide range of disparate diseases.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3464034/

Anti-tumoral action of cannabinoids on hepatocellular carcinoma: role of AMPK-dependent activation of autophagy

“Hepatocellular carcinoma (HCC) is the third cause of cancer-related death worldwide… few therapeutic options are available… we investigated the effects of cannabinoids–a novel family of potential anticancer agents–on the growth of HCC. We found that Δ(9)-tetrahydrocannabinol (Δ(9)-THC, the main active component of Cannabis sativa)… reduced the viability of the human HCC cell lines…cannabinoids were also able to inhibit tumor growth… Our findings may contribute to the design of new therapeutic strategies for the management of HCC.”

http://www.ncbi.nlm.nih.gov/pubmed/21475304