“Endocannabinoids are bioactive lipids that modulate various physiological processes through G-protein-coupled receptors (CB1 and CB2) and other putative targets. By sharing the activation of the same receptors, some phytocannabinoids and a multitude of synthetic cannabinoids mimic the effects of endocannabinoids.
In recent years, a growing interest has been dedicated to the study of cannabinoids properties for their analgesic, antioxidant, anti-inflammatory and neuroprotective effects. In addition to these well-recognized effects, various studies suggest that cannabinoids may affect cell survival, cell proliferation or cell death. These observations indicate that cannabinoids may play an important role in the regulation of cellular homeostasis and, thus, may contribute to tissue remodelling and cancer treatment.
For a long time, the study of cannabinoid receptor signalling has been focused on the classical adenylyl cyclase/cyclic AMP/protein kinase A (PKA) pathway. However, this pathway does not totally explain the wide array of biological responses to cannabinoids. In addition, the diversity of receptors and signalling pathways that endocannabinoids modulate offers an interesting opportunity for the development of specific molecules to disturb selectively the endogenous system.
Moreover, emerging evidences suggest that cannabinoids ability to limit cell proliferation and to induce tumour-selective cell death may offer a novel strategy in cancer treatment.
This review describes the main properties of cannabinoids in cell death and attempts to clarify the different pathways triggered by these compounds that may help to understand the complexity of respective molecular mechanisms and explore the potential clinical benefit of cannabinoids use in cancer therapies.”
https://www.ncbi.nlm.nih.gov/pubmed/28425013
“Mediterranean diet components, such as olive oil and ω-3 polyunsaturated fatty acids (ω-3 PUFAs), can arrest cell growth and promote cell apoptosis.
Recently, olive oil has been demonstrated to modulate type-1 cannabinoid (CB1) receptor gene expression in both human colon cancer cells and rat colon. The aim of this study was to investigate a possible link between olive oil and ω-3 PUFAs effects and CB1 receptor expression in both intestinal and adipose tissue of ApcMin/+ mice.
To confirm the role for the CB1 receptor as a negative modulator of cell proliferation in human colon cancer, CB1 receptor gene expression was also detected in tumor tissue and in surrounding normal mucosa of patients with colorectal cancer (CRC).
Dietary ω-3 PUFAs significantly inhibited intestinal polyp growth in mice, correlating with CB1 receptor gene and protein expression induction. CB1 receptor gene up-regulation was also detected in adipose tissue, suggesting a close communication between cancer cells and the surrounding environment. Tissue CB1 receptor induction was associated with a concurrent inactivation of the Wnt/β-catenin pathway.
Moreover, there was a significant reduction in CB1 receptor gene expression levels in cancer tissue compared to normal surrounding mucosa of patients with CRC, confirming that in cancer the “protective” action of the CB1 receptor is lost.”
https://www.ncbi.nlm.nih.gov/pubmed/28245562
“Colorectal cancer (CRC) is a major health problem in Western countries. The endocannabinoid 2-arachidonoyl-glycerol (2-AG) exerts antiproliferative actions in a number of tumoral cell lines, including CRC cells. Monoacylglycerol lipase (MAGL), a serine hydrolase that inactivates 2-AG, is highly expressed in aggressive human cancer cells. Here, we investigated the role of MAGL in experimental colon carcinogenesis. MAGL, possibly through modulation of angiogenesis, plays a pivotal role in experimental colon carcinogenesis. Pharmacological inhibition of MAGL could represent an innovative therapeutic approach to reduce colorectal tumor progression.” https://www.ncbi.nlm.nih.gov/pubmed/28193521]]>
“In ancient medicine, extracts of the marijuana plant Cannabis sativa were used against diseases of the gastrointestinal (GI) tract. Today, our knowledge of the ingredients of the Cannabis plant has remarkably advanced enabling us to use a variety of herbal and synthetic cannabinoid (CB) compounds to study the endocannabinoid system (ECS), a physiologic entity that controls tissue homeostasis with the help of endogenously produced CBs and their receptors. After many anecdotal reports suggested beneficial effects of Cannabis in GI disorders, it was not surprising to discover that the GI tract accommodates and expresses all the components of the ECS. The following review summarizes important and recent findings on the role of CB receptors and their ligands in the GI tract with emphasis on GI disorders, such as irritable bowel syndrome, inflammatory bowel disease, and colon cancer.” https://www.ncbi.nlm.nih.gov/pubmed/27561826]]>
“Extravirgin olive oil (EVOO) represents the typical lipid source of the Mediterranean diet, an eating habit pattern that has been associated with a significant reduction of cancer risk. Diet is the more studied environmental factor in epigenetics, and many evidences suggest dysregulation of epigenetic pathways in cancer.
The aim of our study was to investigate the effects of EVOO and its phenolic compounds on endocannabinoid system (ECS) gene expression via epigenetic regulation in both human colon cancer cells (Caco-2) and rats exposed to short- and long-term dietary EVOO.
Taken together, our findings demonstrating CB₁ gene expression modulation by EVOO or its phenolic compounds via epigenetic mechanism, both in vitro and in vivo, may provide a new therapeutic avenue for treatment and/or prevention of colon cancer.”
“In ancient medicine, extracts of the marijuana plant Cannabis sativa were used against diseases of the gastrointestinal (GI) tract.
Today, our knowledge of the ingredients of the Cannabis plant has remarkably advanced enabling us to use a variety of herbal and synthetic cannabinoid (CB) compounds to study the endocannabinoid system (ECS), a physiologic entity that controls tissue homeostasis with the help of endogenously produced CBs and their receptors.
After many anecdotal reports suggested beneficial effects of Cannabis in GI disorders, it was not surprising to discover that the GI tract accommodates and expresses all the components of the ECS.
Cannabinoid receptors and their endogenous ligands, the endocannabinoids, participate in the regulation of GI motility, secretion, and the maintenance of the epithelial barrier integrity.
In addition, other receptors, such as the transient receptor potential cation channel subfamily V member 1 (TRPV1), the peroxisome proliferator-activated receptor alpha (PPARα) and the G-protein coupled receptor 55 (GPR55), are important participants in the actions of CBs in the gut and critically determine the course of bowel inflammation and colon cancer.
The following review summarizes important and recent findings on the role of CB receptors and their ligands in the GI tract with emphasis on GI disorders, such as irritable bowel syndrome, inflammatory bowel disease, and colon cancer.”
“We have investigated the effects of cannabinoid agonists and antagonists on tumour necrosis factor-alpha (TNF-alpha)-induced secretion of interleukin-8 from the colonic epithelial cell line, HT-29.
The cannabinoid receptor agonists [(-)-3-[2-hydroxy-4-(1,1-dimethyl-heptyl)-phenyl]4-[3-hydroxypropyl]cyclo-hexan-1-ol] (CP55,940); Delta-9-tetrahydrocannabinol; [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl) methyl] pyrrolo[1,2,3-de]1,4-benzoxazin-6-yl](1-naphthyl) methanone mesylate] (WIN55,212-2) and 1-propyl-2-methyl-3-naphthoyl-indole (JWH 015) inhibited TNF-alpha induced release of interleukin-8 in a concentration-dependent manner.
We conclude that in HT-29 cells, TNF-alpha-induced interleukin-8 release is inhibited by cannabinoids through activation of cannabinoid CB(2) receptors.”
http://www.ncbi.nlm.nih.gov/pubmed/12498928
“Essential involvement of interleukin-8 (IL-8) in acute inflammation.” http://www.ncbi.nlm.nih.gov/pubmed/7964163
“Interleukin-8 (IL-8) is known to possess tumorigenic and proangiogenic properties. Overexpression of IL-8 has been detected in many human tumors, including colorectal cancer (CRC). IL-8 promotes tumor growth, metastasis, chemoresistance and angiogenesis, implying IL-8 to be an important therapeutic target in CRC.” http://www.ncbi.nlm.nih.gov/pubmed/20648559
“Excessive inflammatory responses can emerge as a potential danger for organisms’ health.
Our results indicate that the endogenous cannabinoid system represents a promising therapeutic target for the treatment of intestinal disease conditions characterized by excessive inflammatory responses.
The major active constituent of the plant Cannabis sativa (marijuana), Δ9-tetrahydrocannabinol, and a variety of natural and synthetic cannabinoids have been shown to possess antinociceptive and anti-inflammatory activities.
For millennia, Cannabis preparations have been used in folk medicine for the treatment of a wide variety of disorders, including those affecting the gastrointestinal tract. A century ago, extracts of Cannabis were used in the US to treat gastrointestinal pain of different origins, gastroenteritis, and diarrhea. There are also anecdotal reports suggesting that marijuana may be effective in alleviating symptoms of Crohn disease.
In conclusion, this study shows that the endogenous cannabinoid system is physiologically involved in the protection against excessive inflammation in the colon, both by dampening smooth muscular irritation caused by inflammation and by controlling cellular pathways leading to inflammatory responses.
These results strongly suggest that modulation of the physiological activity of the endogenous cannabinoid system during colonic inflammation might be a promising therapeutic tool for the treatment of several diseases characterized by inflammation of the gastrointestinal tract.”
https://www.jci.org/articles/view/19465
“A mouse study demonstrated that endogenous cannabinoid system signaling is likely to provide intrinsic protection against colonic inflammation. As a result, a hypothesis that phytocannabinoids and endocannabinoids may be useful in the risk reduction and treatment of colorectal cancer has been developed.” http://www.cancer.gov/about-cancer/treatment/cam/hp/cannabis-pdq#section/_7