Preparation and characterization of Δ(9)-tetrahydrocannabinol-loaded biodegradable polymeric microparticles and their antitumoral efficacy on cancer cell lines.

Posted on August 1, 2016 by David

“Cannabinoids present an interesting therapeutic potential as antiemetics, appetite stimulants in debilitating diseases (cancer, AIDS and multiple sclerosis), analgesics, and in the treatment of multiple sclerosis and cancer, among other conditions.

However, despite their high clinical potential, only few dosage forms are available to date.

In this paper, the development of Δ(9)-tetrahydrocannabinol (THC) biodegradable microspheres as an alternative delivery system for cannabinoid parenteral administration is proposed.

As THC has shown therapeutic potential as anticancer drug, the efficacy of the microspheres was tested on different cancer cell lines.

Interestingly, the microspheres were able to inhibit cancer cell proliferation during the nine-day study period.

All the above results suggest that the use of biodegradable microspheres would be a suitable alternative delivery system for THC administration.”

http://www.ncbi.nlm.nih.gov/pubmed/23773072

Endocannabinoid system as a regulator of tumor cell malignancy – biological pathways and clinical significance

Posted on July 19, 2016 by David

“The endocannabinoid system (ECS) comprises cannabinoid receptors (CBs), endogenous cannabinoids, and enzymes responsible for their synthesis, transport, and degradation of (endo)cannabinoids.

To date, two CBs, CB1 and CB2, have been characterized; however, orphan G-protein-coupled receptor GPR55 has been suggested to be the third putative CB.

Several different types of cancer present abnormal expression of CBs, as well as other components of ECS, and this has been shown to correlate with the clinical outcome.

Although most effects of (endo)cannabinoids are mediated through stimulation of classical CBs, they also interact with several molecules, either prosurvival or proapoptotic molecules.

It should be noted that the mode of action of exogenous cannabinoids differs significantly from that of endocannabinoid and results from the studies on their activity both in vivo and in vitro could not be easily compared.

This review highlights the main signaling pathways involved in the antitumor activity of cannabinoids and the influence of their activation on cancer cell biology.

We also discuss changes in the expression pattern of the ECS in various cancer types that have an impact on disease progression and patient survival.

A growing amount of experimental data imply possible exploitation of cannabinoids in cancer therapy.”

https://www.dovepress.com/endocannabinoid-system-as-a-regulator-of-tumor-cell-malignancy-ndash-b-peer-reviewed-article-OTT

Cannabinoids for Symptom Management and Cancer Therapy: The Evidence.

Posted on July 14, 2016 by David

“Cannabinoids bind not only to classical receptors (CB1 and CB2) but also to certain orphan receptors (GPR55 and GPR119), ion channels (transient receptor potential vanilloid), and peroxisome proliferator-activated receptors. Cannabinoids are known to modulate a multitude of monoamine receptors. Structurally, there are 3 groups of cannabinoids.

Multiple studies, most of which are of moderate to low quality, demonstrate that tetrahydrocannabinol (THC) and oromucosal cannabinoid combinations of THC and cannabidiol (CBD) modestly reduce cancer pain.

Dronabinol and nabilone are better antiemetics for chemotherapy-induced nausea and vomiting (CINV) than certain neuroleptics, but are not better than serotonin receptor antagonists in reducing delayed emesis, and cannabinoids have largely been superseded by neurokinin-1 receptor antagonists and olanzapine; both cannabinoids have been recommended for breakthrough nausea and vomiting among other antiemetics. Dronabinol is ineffective in ameliorating cancer anorexia but does improve associated cancer-related dysgeusia.

Multiple cancers express cannabinoid receptors directly related to the degree of anaplasia and grade of tumor.

Preclinical in vitro and in vivo studies suggest that cannabinoids may have anticancer activity.

Paradoxically, cannabinoid receptor antagonists also have antitumor activity.

There are few randomized smoked or vaporized cannabis trials in cancer on which to judge the benefits of these forms of cannabinoids on symptoms and the clinical course of cancer. Smoked cannabis has been found to contain Aspergillosis. Immunosuppressed patients should be advised of the risks of using “medical marijuana” in this regard.”

http://www.ncbi.nlm.nih.gov/pubmed/27407130

Modulation of breast cancer cell viability by a cannabinoid receptor 2 agonist, JWH-015, is calcium dependent

Posted on May 20, 2016 by David

“Breast cancer is the leading cause of cancer-related deaths among women aged 34–50 worldwide, and is the most commonly diagnosed metastasizing tumor in women of all ages. Despite advances in understanding breast cancer as a disease, there remains a critical need for novel disease-modifying therapeutics.

Nonspecific cannabinoids, cannabinoid receptor 2 (CB₂)-selective, as well as cannabinoid receptor 1 (CB₁)-selective compounds have yielded similar antitumor results in several tumor models. The lack of neuronal expression of CB₂ receptors precludes CB₂ selective compounds from inducing the psychotropic effects that typically accompany CB₁ activation.

Our group and others have shown that CB₂ agonists displaying selectivity for the CB₂ receptor can decrease tumor cell viability and significantly attenuate cancer-induced bone pain without displaying psychoactive or addictive properties.

…antitumor effects of cannabinoids have been demonstrated in a variety of tumor models…

The antiproliferative effects of a CB₂ agonist along with our previous work demonstrating significant efficacy in inhibiting bone cancer pain and slowing bone loss in a murine model of advanced breast cancer strongly suggest that CB₂ agonists should be investigated in humans as adjunct therapy for advanced stages of breast cancer.

Cannabinoid compounds, both nonspecific as well as agonists selective for either cannabinoid receptor 1 (CB₁) or cannabinoid receptor 2 (CB₂), have been shown to modulate the tumor microenvironment by inducing apoptosis in tumor cells in several model systems.

The results of this work characterize the actions of a CB₂-selective agonist on breast cancer cells in a syngeneic murine model representing how a clinical presentation of cancer progression and metastasis may be significantly modulated by a G-protein-coupled receptor.

Several groups have shown that both nonselective cannabinoid and CB₂-specific compounds decrease breast cancer viability in vitro and in vivo: Δ⁹-tetrahydrocannabinol and CB₂-selective agonist, JWH-133, have been demonstrated to exert considerable antitumoral effects…”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4847606/

The Influence of Biomechanical Properties and Cannabinoids on Tumor Invasion.

Posted on May 6, 2016 by David

Image result for Cell Adhesion & Migration journal

“Cannabinoids are known to have an anti-tumorous effect, but the underlying mechanisms are only sparsely understood. Mechanical characteristics of tumor cells represent a promising marker to distinguish between tumor cells and the healthy tissue.

We tested the hypothesis whether cannabinoids influence the tumor cell specific mechanical and migratory properties and if these factors are a prognostic marker for the invasiveness of tumor cells.

Here we could show that a “generalized stiffness” is a profound marker for the invasiveness of a tumor cell population in our model and thus might be of high clinical relevance for drug testing.

Additionally cannabinoids were shown to be of potential use for therapeutic approaches of glioblastoma.”

http://www.ncbi.nlm.nih.gov/pubmed/27149140

“Glioblastomas (GBM) are tumors that arise from astrocytes—the star-shaped cells that make up the “glue-like,” or supportive tissue of the brain. These tumors are usually highly malignant (cancerous) because the cells reproduce quickly and they are supported by a large network of blood vessels. Glioblastomas are generally found in the cerebral hemispheres of the brain, but can be found anywhere in the brain or spinal cord.” http://www.abta.org/brain-tumor-information/types-of-tumors/glioblastoma.html?referrer=https://www.google.com/

Targeting Cannabinoid Receptors in Brain Tumors

Posted on May 4, 2016 by David

Image result for springerlink

“Cannabinoids, the active components of Cannabis sativa L., act in the body by mimicking endogenous substances — the endocannabinoids — that activate specific cell surface receptors.

Cannabinoids exert various palliative effects in cancer patients. In addition, cannabinoids inhibit the growth of different types of tumor cells, including glioma cells, in laboratory animals. They do so by modulating key cell signaling pathways, mostly the endoplasmic reticulum stress response, thereby inducing antitumoral actions such as the apoptotic death of tumor cells and the inhibition of tumor angiogenesis.

Of interest, cannabinoids seem to be selective antitumoral compounds as they kill glioma cells but not their nontransformed astroglial counterparts.

On the basis of these preclinical findings, a pilot clinical study of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) in patients with recurrent glioblastoma multiforme has been recently run. The fair safety profile of Δ⁹-THC, together with its possible growth-inhibiting action on tumor cells, may set the basis for future trials aimed at evaluating the potential antitumoral activity of cannabinoids.”

http://link.springer.com/chapter/10.1007%2F978-0-387-74349-3_17

Anticancer mechanisms of cannabinoids.

Posted on March 30, 2016 by David

“In addition to the well-known palliative effects of cannabinoids on some cancer-associated symptoms, a large body of evidence shows that these molecules can decrease tumour growth in animal models of cancer.

They do so by modulating key cell signalling pathways involved in the control of cancer cell proliferation and survival. In addition, cannabinoids inhibit angiogenesis and decrease metastasis in various tumour types in laboratory animals.

In this review, we discuss the current understanding of cannabinoids as antitumour agents, focusing on recent discoveries about their molecular mechanisms of action, including resistance mechanisms and opportunities for their use in combination therapy.

Those observations have already contributed to the foundation for the development of the first clinical studies that will analyze the safety and potential clinical benefit of cannabinoids as anticancer agents.”

http://www.ncbi.nlm.nih.gov/pubmed/27022311

Medical Marijuana Use in Oncology: A Review.

Posted on March 19, 2016 by David

“Medicinal marijuana use is currently legal in 23 states and the District of Columbia. As more states approve marijuana use for medical indications, physicians will be asked by their patients for more information regarding the risks and benefits of use. This article reviews the history, adverse effects, and proposed mechanisms of action of marijuana and summarizes the available literature regarding symptom relief and therapeutic value in patients with cancer.

OBSERVATIONS:

Marijuana in oncology may have potential for use as an antiemetic, for refractory cancer pain, and as an antitumor agent. However, much of the data are based on animal data, small trials, or are outdated.

CONCLUSIONS AND RELEVANCE:

More research is needed in all areas related to the therapeutic use of marijuana in oncology.”

http://www.ncbi.nlm.nih.gov/pubmed/26986677

http://www.thctotalhealthcare.com/category/cancer/

Smoking marijuana reduces cancer risk

Posted on February 16, 2016 by David

“Marijuana reduces cancer risk and kills existing tumors”

“This may be hard to believe — as we’re fairly accustomed to the notion that inhaling smoke is always bad for your health — but research shows smoking marijuana actually decreases the risk for developing lung cancer.

According to multiple study findings published on Cancer.gov, “Cannabinoids appear to kill tumor cells but do not affect their nontransformed counterparts and may even protect them from cell death.”

Dr. Donald Tashkin, professor emeritus of medicine at UCLA, also recently revealed to LA Weekly that after 30 years of studying the effects of marijuana smoke on lung function, he did not find any association between lung cancer and smoking weed.

Smoking marijuana doesn’t lead to impaired lung function either

Tashkin also found smoking marijuana does not lead to impaired lung function even after years of habitual use.”

More: http://extract.suntimes.com/information-resources/10/153/892/smoking-marijuana-reduces-cancer-risk

“Cannabis has been shown to kill cancer cells in the laboratory. Cannabinoids appear to kill tumor cells but do not affect their nontransformed counterparts and may even protect them from cell death.” http://www.cancer.gov/about-cancer/treatment/cam/patient/cannabis-pdq#section/all

http://www.thctotalhealthcare.com/category/cancer/

Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveal a Mechanism for Regulation of Tumor Progression.

Posted on February 5, 2016 by David

“The G-protein-coupled chemokine receptor, CXCR4, generates signals that lead to cell migration, cell proliferation, and other survival mechanisms which result in the metastatic spread of primary tumor cells to distal organs.

Numerous studies have demonstrated that CXCR4 can form homodimers, or can heterodimerize with other GPCRs to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor.

Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells.

Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2, and ultimately, reduced cancer cell functions such as calcium mobilization and cellular chemotaxis.

Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells, as well as CXCR4-mediated migration of immune cells, it is therefore plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4.

Taken together, the data illustrates a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function, and perhaps, tumor progression.”

http://www.ncbi.nlm.nih.gov/pubmed/26841863