IGF-IR pathways in breast cancer.

Posted on May 24, 2016 by David

“Breast cancer is the second leading cause of cancer deaths among women.

Cannabinoid receptor 2 (CNR2 or CB2) is an integral part of the endocannabinoid system.

Although CNR2 is highly expressed in the breast cancer tissues as well as breast cancer cell lines, its functional role in breast tumorigenesis is not well understood.

We observed that estrogen receptor-α negative (ERα-) breast cancer cells highly express epidermal growth factor receptor (EGFR) as well as insulin-like growth factor-I receptor (IGF-IR). We also observed IGF-IR upregulation in ERα+ breast cancer cells.

In addition, we found that higher CNR2 expression correlates with better recurrence free survival in ERα- and ERα+ breast cancer patients.

Our studies showed that CNR2 activation inhibited EGF and IGF-I-induced migration and invasion of ERα+ and ERα- breast cancer cells.

In conclusion, we show that CNR2 activation suppresses breast cancer through novel mechanisms by inhibiting EGF/EGFR and IGF-I/IGF-IR signaling axes.”

http://www.ncbi.nlm.nih.gov/pubmed/27213582

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/

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

Posted on May 2, 2016 by David

“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 mechanism of this modulation remains only partially delineated, and activity induced via the CB₁ and CB₂ receptors may be distinct despite significant sequence homology and structural similarity of ligands.

https://www.dovepress.com/modulation-of-breast-cancer-cell-viability-by-a-cannabinoid-receptor-2-peer-reviewed-article-BCTT

ENDOCANNABINOID SYSTEM: A multi-facet therapeutic target.

Posted on April 19, 2016 by David

Image result for Curr Clin Pharmacol.

“Cannabis sativa is also popularly known as marijuana. It is being cultivated and used by man for recreational and medicinal purposes from many centuries.

Study of cannabinoids was at bay for very long time and its therapeutic value could not be adequately harnessed due to its legal status as proscribed drug in most of the countries.

The research of drugs acting on endocannabinoid system has seen many ups and down in recent past. Presently, it is known that endocannabinoids has role in pathology of many disorders and they also serve “protective role” in many medical conditions.

Several diseases like emesis, pain, inflammation, multiple sclerosis, anorexia, epilepsy, glaucoma, schizophrenia, cardiovascular disorders, cancer, obesity, metabolic syndrome related diseases, Parkinson’s disease, Huntington’s disease, Alzheimer’s disease and Tourette’s syndrome could possibly be treated by drugs modulating endocannabinoid system.

Presently, cannabinoid receptor agonists like nabilone and dronabinol are used for reducing the chemotherapy induced vomiting. Sativex (cannabidiol and THC combination) is approved in the UK, Spain and New Zealand to treat spasticity due to multiple sclerosis. In US it is under investigation for cancer pain, another drug Epidiolex (cannabidiol) is also under investigation in US for childhood seizures. Rimonabant, CB1 receptor antagonist appeared as a promising anti-obesity drug during clinical trials but it also exhibited remarkable psychiatric side effect profile. Due to which the US Food and Drug Administration did not approve Rimonabant in US. It sale was also suspended across the EU in 2008.

Recent discontinuation of clinical trial related to FAAH inhibitor due to occurrence of serious adverse events in the participating subjects could be discouraging for the research fraternity. Despite of some mishaps in clinical trials related to drugs acting on endocannabinoid system, still lot of research is being carried out to explore and establish the therapeutic targets for both cannabinoid receptor agonists and antagonists.

One challenge is to develop drugs that target only cannabinoid receptors in a particular tissue and another is to invent drugs that acts selectively on cannabinoid receptors located outside the blood brain barrier. Besides this, development of the suitable dosage forms with maximum efficacy and minimum adverse effects is also warranted.

Another angle to be introspected for therapeutic abilities of this group of drugs is non-CB1 and non-CB2 receptor targets for cannabinoids.

In order to successfully exploit the therapeutic potential of endocannabinoid system, it is imperative to further characterize the endocannabinoid system in terms of identification of the exact cellular location of cannabinoid receptors and their role as “protective” and “disease inducing substance”, time-dependent changes in the expression of cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27086601

Cannabinoid pharmacology in cancer research: A new hope for cancer patients?

Posted on February 9, 2016 by David

Image result for Eur J Pharmacol.

“Cannabinoids have been used for many centuries to ease pain and in the past decade, the endocannabinoid system has been implicated in a number of pathophysiological conditions, such as mood and anxiety disorders, movement disorders such as Parkinson’s and Huntington’s disease, neuropathic pain, multiple sclerosis, spinal cord injury, atherosclerosis, myocardial infarction, stroke, hypertension, glaucoma, obesity, and osteoporosis.

Several studies have demonstrated that cannabinoids also have anti-cancer activity and as cannabinoids are usually well tolerated and do not produce the typical toxic effects of conventional chemotherapies, there is considerable merit in the development of cannabinoids as potential anticancer therapies.

Whilst the presence of psychoactive effects of cannabinoids could prevent any progress in this field, recent studies have shown the value of the non-psychoactive components of cannabinoids in activating apoptotic pathways, inducing anti-proliferative and anti-angiogenic effects.

The aforementioned effects are suggested to be through pathways such as ERK, Akt, mitogen-activated protein kinase (MAPK) pathways, phosphoinositide 3-kinase (PI3K) pathways and hypoxia inducible factor 1 (HIF1), all of which are important contributors to the hallmarks of cancer.

Many important questions still remain unanswered or are poorly addressed thus necessitating further research at basic pre-clinical and clinical levels. In this review, we address these issues with a view to identifying the key challenges that future research needs to address.”

http://www.ncbi.nlm.nih.gov/pubmed/26852955

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

Ligands for cannabinoid receptors, promising anticancer agents.

Posted on January 15, 2016 by David

Image result for Life Sci.

“Cannabinoid compounds are unique to cannabis and provide some interesting biological properties.

These compounds along with endocannabinoids, a group of neuromodulator compounds in the body especially in brain, express their effects by activation of G-protein-coupled cannabinoid receptors, CB1 and CB2.

There are several physiological properties attributed to the endocannabinoids including pain relief, enhancement of appetite, blood pressure lowering during shock, embryonic development, and blocking of working memory.

On the other hand, activation of endocannabinoid system may be suppresses evolution and progression of several types of cancer.

According to the results of recent studies, CB receptors are over-expressed in cancer cell lines and application of multiple cannabinoid or cannabis-derived compounds reduce tumor size through decrease of cell proliferation or induction of cell cycle arrest and apoptosis along with desirable effect on decrease of tumor-evoked pain.

Therefore, modulation of endocannabinoid system by inhibition of fatty acid amide hydrolase (FAAH), the enzyme, which metabolized endocannabinoids, or application of multiple cannabinoid or cannabis-derived compounds, may be appropriate for the treatment of several cancer subtypes. This review focuses on how cannabinoid affect different types of cancers.”

http://www.ncbi.nlm.nih.gov/pubmed/26764235

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

Control of Breast Cancer by the Endocannabinoid System

Posted on October 2, 2015 by David

“Activation of the endocannabinoid system through CB1, CB2 and additional receptor subtypes results in the inhibition of a broad range of cancers.

The endocannabinoid system was discovered through research focusing on the classical cannabinoid agonist, ?9-tetrahydrocannabinol (?9-THC), and other synthetic cannabinoids.

This proposal will focus on the potential treatment of human breast cancer using cannabinoids as selective antitumor agents.

We have found that cannabinoid compounds activating CB1, CB2 and additional receptor subtypes can inhibit breast cancer cell proliferation and invasiveness and we have discovered down-stream targets that potentially link cannabinoid receptor stimulation to these effects.

Furthermore, our preliminary studies provide evidence that endogenous endocannabinoid tone tonically inhibits metastatic breast cancer cell proliferation and invasiveness through the activation of cannabinoid receptors.

Our preliminary data also suggests that cannabinoid compounds possess selective efficacy, having less adverse effects on the normal human cells from which the breast cancers arise.

Since toxicity in healthy tissue limits the efficacy of current cancer treatments, discovering the mechanism behind selective efficacy in human tissues is of clinical importance.

Cannabinoids can inhibit multiple types of tumor growth in vivo…

Testing the hypotheses outlined in the application may lead to the development of effective inhibitors of breast, and perhaps other, cancers.

This research may also elucidate novel mechanisms related to the anticancer activity of cannabinoids, and will serve to develop the career of the candidate in the field of cancer biology.”

http://grantome.com/grant/NIH/K01-CA111723-01A2

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

The Use of Styrene Maleic Acid Nanomicelles Encapsulating the Synthetic Cannabinoid Analog WIN55,212-2 for the Treatment of Cancer.

Posted on August 10, 2015 by David

“Synthetic cannabinoid WIN55,212-2 (WIN) has shown a promise as an anticancer agent but causes psychoactive side-effects.

In the present study, nano-micelles of styrene maleic acid (SMA)-conjugated WIN were synthesized to reduce side-effects and increase drug efficacy…

SMA-WIN demonstrated characteristics theorized to improve in vivo drug biodistribution.

Potent cytotoxicity was found against breast and prostate cancer cells in vitro, showing promise as a novel treatment against breast and prostate cancer.”

http://www.ncbi.nlm.nih.gov/pubmed/26254360

Bone cell-autonomous contribution of type 2 cannabinoid receptor to breast cancer induced osteolysis.

Posted on July 22, 2015 by David

“The cannabinoid type 2 receptor (CB2) has previously been implicated as a regulator of tumour growth, bone remodelling and bone pain.

However, very little is known about the role of the skeletal CB2 receptor in the regulation of osteoblasts and osteoclasts changes associated with breast cancer. Here, we found that the CB2 selective agonists HU308 and JWH133 reduced the viability of a variety of parental and bone-tropic human and mouse breast cancer cells at high micro-molar concentrations…

When combined with published work, these findings suggest that breast cancer and bone cells exhibit differential responses to treatment with CB2 ligands, depending upon cell type and concentration used.

We therefore conclude that both, CB2 selective activation and antagonism have potential efficacy in cancer associated bone disease but further studies are warranted and ongoing.”

http://www.ncbi.nlm.nih.gov/pubmed/26195631