“CB1 and CB2 are multifunctional cannabinoid-specific receptors considered to be involved in inhibition of tumor development…
To elucidate their roles in hepatocarcinogenesis, we analyzed the expression of these receptors in tumor and matched nontumorous tissues of human hepatocellular carcinoma (HCC) samples.
Our results indicate that CB1 and CB2 have potential as prognostic indicators and suggest possible beneficial effects of cannabinoids on prognosis of patients with HCC.”
“In our previous study, we reported that the cannabinoid receptors CB1 and CB2 are overexpressed in human hepatocellular carcinoma (HCC) tissues. Recently, the antitumor potential of the endogenous cannabinoid anandamide (AEA) has also been addressed. The present study was conducted to investigate the anti-proliferative effects of AEA in HCC cells…
The results of this study demonstrated that AEA inhibited the proliferation of Huh7 cells, resulted in G1 cell cycle arrest and induced apoptosis…
This study defines the anti-proliferative effects of anandamide in HCC cells and suggests that AEA has therapeutic potential in the management of HCC patients.”
“Autophagy can promote cell survival or cell death, but the molecular basis underlying its dual role in cancer remains obscure. Here we demonstrate that Δ9-tetrahydrocannabinol (THC), the main active component of marijuana, induces human glioma cell death through stimulation of autophagy…We also showed that autophagy is upstream of apoptosis in cannabinoid-induced human and mouse cancer cell death and that activation of this pathway was necessary for the antitumor action of cannabinoids in vivo.”
“These findings describe a mechanism by which THC can promote the autophagic death of human and mouse cancer cells and provide evidence that cannabinoid administration may be an effective therapeutic strategy for targeting human cancers.
Δ9-Tetrahydrocannabinol (THC), the main active component of marijuana, exerts a wide variety of biological effects by mimicking endogenous substances — the endocannabinoids — that bind to and activate specific cannabinoid receptors. One of the most exciting areas of research in the cannabinoid field is the study of the potential application of cannabinoids as antitumoral agents.
Cannabinoid administration has been found to curb the growth of several types of tumor xenografts in rats and mice…
Considering that no signs of toxicity were observed in the clinical trial patients or in tumor-bearing animals treated intracranially, peritumorally, or intraperitoneally with THC, and that no overt toxic effects have been reported in other clinical trials of cannabinoid use in cancer patients for various applications (e.g., inhibition of nausea, vomiting, and pain) and using different routes of administration (e.g., oral, oro-mucosal) our findings support that safe, therapeutically efficacious doses of THC may be reached in cancer patients.”
“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
“This study examines the current knowledge of physiological and clinical effects of tetrahydrocannabinol (THC) and cannabidiol (CBD) and presents a rationale for their combination in pharmaceutical preparations. Cannabinoid and vanilloid receptor effects as well as non-receptor mechanisms are explored, such as the capability of THC and CBD to act as anti-inflammatory substances independent of cyclo-oxygenase (COX) inhibition.
CBD is demonstrated to antagonise some undesirable effects of THC including intoxication, sedation and tachycardia, while contributing analgesic, anti-emetic, and anti-carcinogenic properties in its own right.
In modern clinical trials, this has permitted the administration of higher doses of THC, providing evidence for clinical efficacy and safety for cannabis based extracts in treatment of spasticity, central pain and lower urinary tract symptoms in multiple sclerosis, as well as sleep disturbances, peripheral neuropathic pain, brachial plexus avulsion symptoms, rheumatoid arthritis and intractable cancer pain. Prospects for future application of whole cannabis extracts in neuroprotection, drug dependency, and neoplastic disorders are further examined.
The hypothesis that the combination of THC and CBD increases clinical efficacy while reducing adverse events is supported.”
“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
“A federal study completed more than two years ago reportedly found that marijuana’s main ingredient did not cause cancer in laboratory animals. A 126-page report on the $2 million study has not been published, although expert reviewers found in June 1994 that the scientific methods used and the conclusions reached were sound, The Boston Globe reported today.
The findings go against the contention of some federal officials that marijuana is carcinogenic. The study will likely add grist to the debate over using marijuana for medical treatment.
A spokesman for White House drug policy adviser Barry R. McCaffrey said his office was not aware of the study.
The Globe said the National Toxicology Program study was revealed earlier this month in a newsletter called AIDS Treatment News.
According to the probe, high doses of the main active ingredient in marijuana, _ tetrahydrocannabinol, or THC _ were put directly into the stomachs of mice and rats daily for two years.
“We found absolutely no evidence of cancer,” said John Bucher, deputy director of the National Toxicology Program.
Because the animals were not exposed to marijuana smoke, the potential of inhaled marijuana to cause cancer was not looked at.
The study was overseen by the Federal Drug Administration, the National Cancer Institute and other federal agencies.
Bucher said publication of the report was overdue, but his agency had not been pressured to bury it. A personnel shortage caused the delay, he said.
The New England Journal of Medicine has come out in favor of allowing doctors to prescribe marijuana for medical purposes.
Some doctors believe marijuana can relieve internal eye pressure in glaucoma, control nausea in cancer patients on chemotherapy and combat the severe weight loss seen in AIDS patients.
However, Clinton administration officials note that such uses of marijuana have not been proved.”
Associated Press, Jan 30, 1997 BOSTON
“delta 9-Tetrahydrocannabinol (delta 9-THC) was studied for potential carcinogenicity in rodents because it is the principal psychoactive ingredient in marihuana and it has potential medicinal uses. delta 9-THC in corn oil was administered by gavage to groups of male and female Fischer rats and B6C3F1 mice…
Decreased tumor incidences…
…There was no evidence that delta 9-THC was carcinogenic in rats or mice.”