A cannabidiol-loaded Mg-gallate metal-organic framework-based potential therapeutic for glioblastomas

 “Cannabidiol (CBD) has been shown to slow cancer cell growth and is toxic to human glioblastoma cell lines. Thus, CBD could be an effective therapeutic for glioblastoma.

In the present study, we explored the anticancer effect of cannabidiol loaded magnesium-gallate (CBD/Mg-GA) metal-organic framework (MOF) using the rat glioma brain cancer (C6) cell line.

Bioactive and microporous magnesium gallate MOF was employed for simultaneous delivery of two potential anticancer agents (gallic acid and CBD) to the cancer cells. Gallic acid (GA), a polyphenolic compound, is part of the MOF framework, while CBD is loaded within the framework. Slow degradation of CBD/Mg-GA MOF in physiological fluids leads to sustained release of GA and CBD.

CBD’s anti-cancer actions target mitochondria, inducing their dysfunction and generation of harmful reactive oxygen species (ROS). Anticancer effects of CBD/Mg-GA include a significant increase in ROS production and a reduction in anti-inflammatory responses as reflected by a significant decrease in TNF-α expression levels. Molecular mechanisms that underlie these effects include the modulation of NF-κB expression, triggering the apoptotic cascades of glioma cells. CBD/Mg-GA MOF has potential anti-cancer, anti-inflammatory and anti-oxidant properties.

Thus, the present study demonstrates that CBD/Mg-GA MOF may be a promising therapeutic for glioblastoma.”

https://pubmed.ncbi.nlm.nih.gov/33657198/

https://pubs.rsc.org/en/content/articlelanding/2021/TB/D0TB02780D#!divAbstract

Graphical abstract: A cannabidiol-loaded Mg-gallate metal–organic framework-based potential therapeutic for glioblastomas

Cannabidiol inhibits human glioma by induction of lethal mitophagy through activating TRPV4

Publication Cover“Glioma is the most common primary malignant brain tumor with poor survival and limited therapeutic options. The non-psychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against glioma; however, the molecular target and mechanism of action of CBD in glioma are poorly understood.

Here we investigated the molecular mechanisms underlying the antitumor effect of CBD in preclinical models of human glioma.

Our results showed that CBD induced autophagic rather than apoptotic cell death in glioma cells. We also showed that CBD induced mitochondrial dysfunction and lethal mitophagy arrest, leading to autophagic cell death. Mechanistically, calcium flux induced by CBD through TRPV4 (transient receptor potential cation channel subfamily V member 4) activation played a key role in mitophagy initiation. We further confirmed TRPV4 levels correlated with both tumor grade and poor survival in glioma patients. Transcriptome analysis and other results demonstrated that ER stress and the ATF4-DDIT3-TRIB3-AKT-MTOR axis downstream of TRPV4 were involved in CBD-induced mitophagy in glioma cells. Lastly, CBD and temozolomide combination therapy in patient-derived neurosphere cultures and mouse orthotopic models showed significant synergistic effect in both controlling tumor size and improving survival.

Altogether, these findings showed for the first time that the antitumor effect of CBD in glioma is caused by lethal mitophagy and identified TRPV4 as a molecular target and potential biomarker of CBD in glioma. Given the low toxicity and high tolerability of CBD, we therefore propose CBD should be tested clinically for glioma, both alone and in combination with temozolomide.”

https://pubmed.ncbi.nlm.nih.gov/33629929/

https://www.tandfonline.com/doi/abs/10.1080/15548627.2021.1885203?journalCode=kaup20

A phase 1b randomised, placebo-controlled trial of nabiximols cannabinoid oromucosal spray with temozolomide in patients with recurrent glioblastoma

British Journal of Cancer“Preclinical data suggest some cannabinoids may exert antitumour effects against glioblastoma (GBM). Safety and preliminary efficacy of nabiximols oromucosal cannabinoid spray plus dose-intense temozolomide (DIT) was evaluated in patients with first recurrence of GBM.

Results: The most common treatment-emergent adverse events (TEAEs; both parts) were vomiting, dizziness, fatigue, nausea and headache. Most patients experienced TEAEs that were grade 2 or 3 (CTCAE). In Part 2, 33% of both nabiximols- and placebo-treated patients were progression-free at 6 months. Survival at 1 year was 83% for nabiximols- and 44% for placebo-treated patients (p = 0.042), although two patients died within the first 40 days of enrolment in the placebo arm. There were no apparent effects of nabiximols on TMZ PK.

Conclusions: With personalised dosing, nabiximols had acceptable safety and tolerability with no drug-drug interaction identified. The observed survival differences support further exploration in an adequately powered randomised controlled trial.”

https://pubmed.ncbi.nlm.nih.gov/33623076/

https://www.nature.com/articles/s41416-021-01259-3

Synthetic Cannabinoids Induce Autophagy and Mitochondrial Apoptotic Pathways in Human Glioblastoma Cells Independently of Deficiency in TP53 or PTEN Tumor Suppressors

cancers-logo“Glioblastomas (GBMs) are aggressive brain tumors with frequent genetic alterations in TP53 and PTEN tumor suppressor genes rendering resistance to standard chemotherapeutics. Cannabinoid type 1 and 2 (CB1/CB2) receptor expression in GBMs and antitumor activity of cannabinoids in glioma cells and animal models, raised promises for a targeted treatment of these tumors. The susceptibility of human glioma cells to CB2-agonists and their mechanism of action are not fully elucidated. We determined CB1 and CB2 expression in 14 low-grade and 21 high-grade tumor biopsies, GBM-derived primary cultures and established cell lines. The non-selective CB receptor agonist WIN55,212-2 (but not its inactive enantiomer) or the CB2-selective agonist JWH133 induced apoptosis in patient-derived glioma cultures and five established glioma cell lines despite p53 and/or PTEN deficiency. Growth inhibitory efficacy of cannabinoids correlated with CB1/CB2 expression (EC50 WIN55,212-2: 7.36-15.70 µM, JWH133: 12.15-143.20 µM). Treatment with WIN55,212-2 or JWH133 led to activation of the apoptotic mitochondrial pathway and DNA fragmentation. Synthetic cannabinoid action was associated with the induction of autophagy and knockdown of autophagy genes augmented cannabinoid-induced apoptotic cell death. The high susceptibility of human glioblastoma cells to synthetic cannabinoids, despite genetic defects contributing to apoptosis resistance, makes cannabinoids promising anti-glioma therapeutics.”

https://pubmed.ncbi.nlm.nih.gov/33499365/

“Glioblastomas (GBMs) are aggressive brain tumors with frequent genetic defects in TP53 and PTEN tumor suppressor genes, which render tumors refractory to standard chemotherapeutics.

Natural and synthetic cannabinoids showed antitumor activity in glioma cells and animal glioma models.

Due to differences in the expression of cannabinoid type 2 receptors (CB2), which are abundant in GBMs but absent from a healthy brain, we tested synthetic cannabinoids for their ability to kill numerous glioma cells. We performed multiple biochemical analyses to determine which cell death pathways are activated in human glioma cells. We demonstrate high susceptibility of human glioblastoma cells to synthetic cannabinoids, despite genetic defects contributing to apoptosis resistance, which makes cannabinoids promising anti-glioma therapeutics.”

https://www.mdpi.com/2072-6694/13/3/419

Cannabigerol Is a Potential Therapeutic Agent in a Novel Combined Therapy for Glioblastoma

cells-logo“Glioblastoma is the most aggressive cancer among primary brain tumours. As with other cancers, the incidence of glioblastoma is increasing; despite modern therapies, the overall mean survival of patients post-diagnosis averages around 16 months, a figure that has not changed in many years. Cannabigerol (CBG) has only recently been reported to prevent the progression of certain carcinomas and has not yet been studied in glioblastoma. Here, we have compared the cytotoxic, apoptotic, and anti-invasive effects of the purified natural cannabinoid CBG together with CBD and THC on established differentiated glioblastoma tumour cells and glioblastoma stem cells. CBG and THC reduced the viability of both types of cells to a similar extent, whereas combining CBD with CBG was more efficient than with THC. CBD and CBG, both alone and in combination, induced caspase-dependent cell apoptosis, and there was no additive THC effect. Of note, CBG inhibited glioblastoma invasion in a similar manner to CBD and the chemotherapeutic temozolomide. We have demonstrated that THC has little added value in combined-cannabinoid glioblastoma treatment, suggesting that this psychotropic cannabinoid should be replaced with CBG in future clinical studies of glioblastoma therapy.”

https://pubmed.ncbi.nlm.nih.gov/33562819/

“Among primary brain tumours, glioblastoma is the most aggressive. As early relapses are unavoidable despite standard-of-care treatment, the cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) alone or in combination have been suggested as a combined treatment strategy for glioblastomas. However, the known psychoactive effects of THC hamper its medical applications in these patients with potential cognitive impairment due to the progression of the disease. Therefore, nontoxic cannabigerol (CBG), being recently shown to exhibit anti-tumour properties in some carcinomas, is assayed here for the first time in glioblastoma with the aim to replace THC. We indeed found CBG to effectively impair the relevant hallmarks of glioblastoma progression, with comparable killing effects to THC and in addition inhibiting the invasion of glioblastoma cells. Moreover, CBG can destroy therapy-resistant glioblastoma stem cells, which are the root of cancer development and extremely resistant to various other treatments of this lethal cancer. CBG should present a new yet unexplored adjuvant treatment strategy of glioblastoma.”

https://www.mdpi.com/2073-4409/10/2/340

Cannabis and its Constituents for Cancer: History, Biogenesis, Chemistry and Pharmacological Activities

Pharmacological Research “Cannabis has long been used for healing and recreation in several regions of the world. Over 400 bioactive constituents, including more than 100 phytocannabinoids, have been isolated from this plant. The non-psychoactive cannabidiol (CBD) and the psychoactive Δ9-tetrahydrocannabinol (Δ9-THC) are the major and widely studied constituents from this plant.

Cannabinoids exert their effects through the endocannabinoid system (ECS) that comprises cannabinoid receptors (CB1, CB2), endogenous ligands, and metabolizing enzymes. Several preclinical studies have demonstrated the potential of cannabinoids against leukemia, lymphoma, glioblastoma, and cancers of the breast, colorectum, pancreas, cervix and prostate.

Cannabis and its constituents can modulate multiple cancer related pathways such as PKB, AMPK, CAMKK-β, mTOR, PDHK, HIF-1α, and PPAR-γ. Cannabinoids can block cell growth, progression of cell cycle and induce apoptosis selectively in tumour cells. Cannabinoids can also enhance the efficacy of cancer therapeutics. These compounds have been used for the management of anorexia, queasiness, and pain in cancer patients.

Cannabinoid based products such as dronabinol, nabilone, nabiximols, and epidyolex are now approved for medical use in cancer patients. Cannabinoids are reported to produce a favourable safety profile. However, psychoactive properties and poor bioavailability limit the use of some cannabinoids. The Academic Institutions across the globe are offering training courses on cannabis. How cannabis and its constituents exert anticancer activities is discussed in this article. We also discuss areas that require attention and more extensive research.”

https://pubmed.ncbi.nlm.nih.gov/33246167/

https://www.sciencedirect.com/science/article/abs/pii/S1043661820316108?via%3Dihub

Education and communication are critical to effectively incorporating cannabis into cancer treatment

“Providers need to be better equipped to discuss medical cannabis with patients even if they are not willing to prescribe it. The oncology community would be well served to ensure that providers are aware of existing cannabis research and are able to incorporate it into their communications with patients instead of leaving patients to figure out medical cannabis on their own.”

https://pubmed.ncbi.nlm.nih.gov/32986251/

https://acsjournals.onlinelibrary.wiley.com/doi/10.1002/cncr.33204

Cancer patients’ experiences with medicinal cannabis-related care

 “Background: Little is known about medical cannabis (MC)-related care for patients with cancer using MC.

Methods: Semistructured telephone interviews were conducted in a convenience sample of individuals (n = 24) with physician-confirmed oncologic diagnoses and state/district authorization to use MC (Arizona, California, Florida, Illinois, Massachusetts, Oregon, New York, and Washington, DC) from April 2017 to March 2019. Standard qualitative techniques were used to assess the degree of MC-related health care oversight, MC practices, and key information sources.

Results: Among 24 participants (median age, 57 years; range, 30-71 years; 16 women [67%]), MC certifications were typically issued by a professional new to a patient’s care after a brief, perfunctory consultation. Patients disclosed MCuse to their established medical teams but received little medical advice about whether and how to use MC. Patients with cancer used MC products as multipurpose symptom management and as cancer-directed therapy, sometimes in lieu of standard-of-care treatments. Personal experimentation, including methodical self-monitoring, was an important source of MC know-how. Absent formal advice from medical professionals, patients relied on nonmedical sources for MC information.

Conclusions: Patients with cancer used MC with minimal medical oversight. Most received MC certifications through brief meetings with unfamiliar professionals. Participants desired but were often unable to access high-quality clinical information about MC from their established medical teams. Because many patients are committed to using MC, a product sustained by a growing industry, medical providers should familiarize themselves with the existing data for MM and its limitations to address a poorly met clinical need.”

https://pubmed.ncbi.nlm.nih.gov/32986266/

“Notably, oncology patients reported using medical cannabis (MC) for symptom management and as cancer‐directed therapy, sometimes instead of traditional treatments.”

https://acsjournals.onlinelibrary.wiley.com/doi/10.1002/cncr.33202

Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis

cancers-logo“In recent years, and even more since its legalization in several jurisdictions, cannabis and the endocannabinoid system have received an increasing amount of interest related to their potential exploitation in clinical settings. Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.”

https://pubmed.ncbi.nlm.nih.gov/32708138/

https://www.mdpi.com/2072-6694/12/7/1985

The Expression Level of Cannabinoid Receptors Type 1 and 2 in the Different Types of Astrocytomas

 SpringerLink“Astrocytomas, the most prevalent primary brain tumors, can be divided by histology and malignancy levels into four following types: pilocytic astrocytoma (grade I), diffuse fibrillary astrocytoma (grade II), anaplastic astrocytoma (grade III), and glioblastoma multiforme (grade IV). For high grade astrocytomas (grade III and grade IV), blood vessels formation is considered as the most important property.

The distribution of cannabinoid receptors type 1 (CB1) and cannabinoid receptor type 2 (CB2) in blood vessels and tumor tissue of astrocytoma is still controversial. Asrocytoma tissues were collected from 45 patients under the condition of tumor-related neurosurgical operation. The expression of CB1 and CB2 receptors was assessed using immunofluorescence, quantitative real-time RT-PCR and western blotting.

The results indicated an increased expression of CB1 receptors in tumor tissue. There was a significant difference in the mount of CB2 receptors in blood vessels. More was observed in the grade III and glioblastoma (grade IV) than astrocytoma of grade II and control.

This study suggested that, the expression increase of cannabinoid receptors is an index for astrocytoma malignancy and can be targeted as a therapeutic approach for the inhibition of astrocytoma growth among patients.”

https://pubmed.ncbi.nlm.nih.gov/32623617/

https://link.springer.com/article/10.1007%2Fs11033-020-05636-8