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Cancer Research Shows How Cannabinoids Fight Tumors

Brain Cancer. The effectiveness of cannabinoids in fighting glioblastoma multiforme (GBM), a form of brain cancer that is highly resistant to current treatments, has been demonstrated in numerous preclinical studies. New research shows that a combination of THC, CBD, and temozolomide (TMZ) "remarkably reduces the growth of glioma." The study revealed tumor growth is inhibited in part through "the stimulation of autophagy-mediated apoptosis," the biologic degradation of cells that leads to them dying off. The Spanish researchers conclude that "the combined administration of TMZ and cannabinoids could be therapeutically exploited for the management of GBM."

Torres S, et al. 2011. A combined preclinical therapy of cannabinoids and temozolomide against glioma. Mol Cancer Ther. 2011 Jan;10(1):90-103.

Oral Cancer. Medical researchers at the University of California report cannabinoids alleviate oral cancer pain and slow the spread of the disease both in vitro and in vivo. They also identified CB1 and CB2 cannabinoid receptors in human oral cancer cells. They suggest the endocannabinoid system may play "a direct role" in pain and proliferation. Noting proliferation of cancer cells was "significantly attenuated in a dose-dependent manner" by cannabinoids, they conclude "the systemic administration" of cannabinoids "may reduce morbidity and mortality of oral cancer."

Saghafi N, et al. 2011. Cannabinoids attenuate cancer pain and proliferation in a mouse model. Neurosci Lett. 488(3):247-51.

Gastric Cancer. Previous studies have shown cannabinoids significantly decrease the spread of gastric cancer tumors and kill off malignant cells. South Korean researchers have recently discovered some of the biologic mechanisms for those tumor-fighting properties. The new research on cellular mediators indicates cannabinoids play a role in halting cell cycles that cause the cancer to spread.

Park JM, et al. 2011. Antiproliferative mechanism of a cannabinoid agonist by cell cycle arrest in human gastric cancer cells. J Cell Biochem. Feb 10.

Cannabinoids Help MS Symptoms, Progression

Italian researchers used an animal model of multiple sclerosis to investigate the efficacy of cannabis extracts on motor symptoms. They found that treating with a THC-rich extract over time "resulted in a significant reduction of neurological deficits," that treatment with CBD affected only the relapse phase, and that combined THC-CBD treatment was ineffective. They suggest further investigation on each cannabinoid's action but conclude that cannabis extracts have potential for managing MS.

Another Italian research team reviewed studies on cannabinoid receptors in the lower urinary tract and their role in controlling urinary tract function, including the treatment of bladder dysfunction resulting from MS, finding that systemic cannabinoids may be clinically useful.
British scientists reviewing the clinical data on treating MS with cannabinoids note patient reports of symptomatic relief are confirmed by data showing cannabinoids improve muscle stiffness and spasms, neuropathic pain, and sleep and bladder disturbance. They note new evidence suggests that cannabinoids may affect "fundamental processes" in the progression of MS. They suggest "cannabinoids may have a longer term role in reducing disability and progression in MS."

Scientists who examined brain samples of deceased MS patients for CB1 and CB2 receptors, as well as an enzyme related to the synthesis of endocannabinoids, found differences in receptor concentration that correlated to MS damage. Their findings support animal studies that suggest the endocannabinoid system has a role in MS progression and cellular response to injuries from the disease.

Buccellato E, et al. 2011. Acute and chronic cannabinoid extracts administration affects motor function in a CREAE model of multiple sclerosis. J Ethnopharmacol. 133(3):1033-8.
Zajicek JP, Apostu VI. 2011. Role of cannabinoids in multiple sclerosis. CNS Drugs. 1;25(3):187-201.
Zhang H,et al. 2011. Cannabinoid Receptor and N-acyl Phosphatidylethanolamine Phospholipase D-Evidence for Altered Expression in Multiple Sclerosis. Brain Pathol.
Ruggieri MR Sr. 2011. Cannabinoids: potential targets for bladder dysfunction. Handb Exp Pharmacol. (202):425-51.

Studies Show Endocannabinoids Role in Anxiety Disorders

The anxiolytic, or anti-anxiety, properties of cannabis have been reported by sufferers of post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD) and others. Two new studies suggest that inhibiting the natural enzymes that break down endogenous cannabinoids may produce similar effects. Using a mouse model of obsessive compulsive behavior, they were able to show that increasing the natural cannabinoids by blocking the chemicals that degrade them decreased the behavior similar to THC but without the side effect of depressed motor activity. Similarly, Brazilian researchers published a review of the role of endocannabinoids in anxiety, noting that enhancement of endogenous cannabinoids avoids the dosage sensitivity to plant and synthetic cannabinoids such as THC, which frequently reduces anxiety in low doses but can trigger it in larger ones.

Kinsey SG, et al. 2011. Inhibition of endocannabinoid catabolic enzymes elicits anxiolytic-like effects in the marble burying assay. Pharmacol Biochem Behav. 98(1):21-7.
Gomes FV, et al. 2010. Facilitation of CB1 receptor-mediated neurotransmission decreases marble burying behavior in mice. Prog Neuropsychopharmacol Biol Psychiatry.
Moreira FA, Wotjak CT. 2010. Cannabinoids and anxiety. Curr Top Behav Neurosci. 2:429-50.

Cannabinoids May Regulate Diabetes

Many people with diabetes turn to cannabis to treat their neuropathic pain. But recent research reveals that the endocannabinoid system is implicated in the regulation of insulin production and blood glucose. The majority of studies indicate that endocannabinoids in the pancreas decrease insulin secretion, but other studies have shown the opposite. As a Johns Hopkins researcher notes, "the exact nature of the effects of endocannabinoids on insulin secretion require rigorous study examining both acute and long-term effects at physiologically relevant doses employing both whole animal and clinically relevant models such as human islets in vitro and explanted in vivo, in rodent models of diabetes." What is clear is that the regulatory role of endocannabinoids in many of the body's most complex physiologic systems suggests a target for cannabinoid-based therapies.

Kim W, et al. 2011. Cannabinoids Inhibit Insulin Receptor Signaling in Pancreatic {beta}-Cells. Diabetes. Feb 23.
Doyle ME. 2011. The role of the endocannabinoid system in islet biology. Curr Opin Endocrinol Diabetes Obes. Feb 9.

Cannabinoids May Provide Treatment for Endometriosis

Scientists at Florida State University investigated the role of the endocannabinoid system in endometriosis, a disease common in women that is associated with severe pain and is difficult to treat. Using a rat model, they discovered CB1 cannabinoid receptors throughout the abnormal growths that characterize endometriosis. Blocking those CB1 receptors increased pain sensitivity, while stimulating them reduced it. They conclude that the endocannabinoid system plays a role in the development of the abnormal growths and pain associated with endometriosis, suggesting cannabinoids may provide "badly-needed new treatments."
Dmitrieva N,et al. 2010. Endocannabinoid involvement in endometriosis. Pain. Dec;151(3):703-10.

Cannabinoid Analgesic Action Studied

While the ability of cannabis and cannabinoids to control chronic pain is well known and amply demonstrated by a variety of historical, anecdotal, and clinical reports, the effect of different dosages, individual cannabinoids, and the mechanisms of action on different types of pain are still being investigated.
A review by German researchers notes that while "an increasing number of randomized, double-blind, placebo-controlled studies have shown the efficacy of cannabinoids" for treating chronic pain and painful spasticity, cannabinoids have not shown "convincing reduction of acute pain." Because patients who have problems adapting to stress and for whom other pain treatments have failed are the most likely to be helped by treatment with cannabinoids, they suggest exploring different modes of administration and new types of "endocannbinoid modulators."
Karst M, et al. 2010. Role of cannabinoids in the treatment of pain and (painful) spasticity. Drugs. 70(18):2409-38.
The pain-control mechanisms for two non-psychoactive cannabinoids -- cannabidiol (CBD) and cannabichromene (CBC) -- have been demonstrated in an animal study conducted by Italian researchers. By monitoring the electrical activity of neurons in the brainstem, they found that both acted in a dose-dependent manner on the activity of proteins involved in a key pain pathway, though twice as much CBC as CBD was necessary to achieve maximum pain relief. Treating with CBC and CBD was also found to elevate endocannabinoid levels. The researchers conclude that "these compounds might represent useful therapeutic agents with multiple mechanisms of action."
Maione S, et al. 2011. Non-psychoactive cannabinoids modulate the descending pathway of antinociception in anaesthetized rats through several mechanisms of action. Br J Pharmacol. 162(3):584-96.

Cannabinoid Control of Nausea Explored

Researchers have recently revealed more about how cannabinoids control nausea. The anti-emetic properties of cannabis is one of its more well-established therapeutic uses, and is also one of the primary indications for prescribing marinol, the synthetic THC pill. A team of Canadian scientists using an animal study have now located an area of the brainstem that may be responsible for the effect. They also demonstrated that not just THC but CBD, the second most prevalent cannabinoid in the plant, has powerful anti-nausea effects within a limited dose range.