“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.”
“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.”
“Notably, oncology patients reported using medical cannabis (MC) for symptom management and as cancer‐directed therapy, sometimes instead of traditional treatments.”
“Prostate cancer is a major cause of death among men worldwide.
Recent preclinical evidence implicates cannabinoids as powerful regulators of cell growth and differentiation, as well as potential anti-cancer agents.
The aim of this review was to evaluate the effect of cannabinoids on in vivo prostate cancer models.
We identified six studies that were all found to be based on in vivo/xenograft animal models.
All studies have reported that the treatment of prostate cancers in in vivo/xenograft models with various cannabinoids decreased the size of the tumor, the outcomes of which depended on the dose and length of treatment.
Within the limitation of these identified studies, cannabinoids were shown to reduce the size of prostate cancer tumors in animal models.”
“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.”
“The recent announcement of marijuana legalization in Canada spiked many discussions about potential health benefits of Cannabis sativa. Cannabinoids are active chemical compounds produced by cannabis, and their numerous effects on the human body are primarily exerted through interactions with cannabinoid receptor types 1 (CB1) and 2 (CB2). Cannabinoids are broadly classified as endo-, phyto-, and synthetic cannabinoids. In this review, we will describe the activity of cannabinoids on the cellular level, comprehensively summarize the activity of all groups of cannabinoids on various cancers and propose several potential mechanisms of action of cannabinoids on cancer cells.”
“Endocannabinoids and phytocannabinoids can be used for cancer therapy. Cannabis extracts have stronger anti-tumor capacity than single cannabinoids. Combination of several cannabinoids may have more potent effect on cancer.”
“Endo-, phyto- and synthetic cannabinoids have been proposed as promising anti-cancer agents able to impair cancer cells’ behavior without affecting their non-transformed counterparts.
However, cancer outcome depends not only on cancer cells’ activity, but also on the stromal cells, which coevolve with cancer cells to sustain tumor progression.
Here, we show for the first time that cannabinoid treatment impairs the activation and the reactivity of cancer-associated fibroblasts (CAFs), the most represented stromal component of prostate tumor microenvironment.
Overall, our data strongly support the use of cannabinoids as anti-tumor agents in prostate cancer, since they are able to simultaneously strike both cancer and stromal cells.”
“In recent years, the endocannabinoid system has received great interest as a potential therapeutic target in numerous pathological conditions.
Cannabinoids have shown an anticancer potential by modulating several pathways involved in cell growth, differentiation, migration, and angiogenesis.
However, the therapeutic efficacy of cannabinoids is limited to the treatment of chemotherapy-induced symptoms or cancer pain, but their use as anticancer drugs in chemotherapeutic protocols requires further investigation.
In this paper, we reviewed the role of cannabinoids in the modulation of signaling mechanisms implicated in tumor progression.”
“In addition to the symptomatic therapy of cancer patients, the antitumor effects of cannabinoids (whether in monotherapy or in combination with other cancer therapies) have promising potential in the treatment of cancer patients.” https://www.ncbi.nlm.nih.gov/pubmed/31950844
“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. In addition, cannabinoids inhibit angiogenesis and decrease metastasis in various tumour types in laboratory animals. Thus, numerous studies have provided evidence that thc and other cannabinoids exhibit antitumour effects in a wide array of animal models of cancer.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4791144/
“Antitumour actions of cannabinoids.” https://www.ncbi.nlm.nih.gov/pubmed/30019449
“The endocannabinoid system as a target for the development of new drugs for cancer therapy” https://www.ncbi.nlm.nih.gov/pubmed/12723496
“Cannabinoids as Anticancer Drugs.” https://www.ncbi.nlm.nih.gov/pubmed/28826542
“Prostate cancer patients receiving androgen-deprivation therapy (ADT) often experience a combination of disease symptoms and treatment side effects. The therapeutic use of cannabis to alleviate these side effects has not been studied, despite increasing patient interest. With the increasing availability of cannabis, it is important for clinicians to understand the prevalence, predictors, and perceived benefits of cannabis use among patients with prostate cancer.
Questionnaire data revealed that 23.2% of surveyed men had recently used cannabis. In contrast, 5.8% of men had detectable levels of THC metabolite in their urine. Combined questionnaire and urine data revealed that cannabis users were significantly younger (p=0.003) and had lower testosterone levels (p=0.003) than non-users. The majority of men experiencing common ADT side effects reported some degree of relief following cannabis use.
Cannabis use among men with advanced prostate cancer receiving ADT is more prevalent than in the general population and the majority of other oncological cohorts. Lower testosterone levels and reported therapeutic benefit among cannabis users warrants confirmation in appropriate clinical trials.”
“Phytocannabinoids are unique terpenophenolic compounds predominantly produced in the glandular trichomes of the cannabis plant (Cannabis sativa L.). The delta-9- tetrahydrocannabinol (THC) is the main active constituent responsible for the plant’s psychoactive effect and, together with the non- psychoactive cannabidiol (CBD), the most investigated naturally occurring cannabinoid.
The first report on the antitumor properties of cannabis compounds appeared more than forty years ago, but the potential of targeting the endocannabinoid system in cancer has recently attracted increasing interest. Our study aimed to review the last decade’s findings on the anticancer potential of plant- derived cannabinoids and the possible mechanisms of their activity.
A large body of in vitro data has been accumulated demonstrating that phytocannabinoids affect a wide spectrum of tumor cells, including gliomas, neuroblastomas, hepatocarcinoma as well as skin, prostate, breast, cervical, colon, pancreatic, lung and hematological cancer.
It has been found that they can stop the uncontrolled growth of cancer cells through the cell-cycle arrest, inhibition of cell proliferation and induction of autophagy and apoptosis. They can also block all the steps of tumor progression, including tumor cell migration, adhesion and invasion as well as angiogenesis. The observed effects are mainly mediated by the cannabinoid CB1 and/or CB2 receptors, although some other receptors and mechanisms unrelated to receptor stimulation may also be involved.
The majority of available animal studies confirmed that phytocannabinoids are capable of effectively decreasing cancer growth and metastasis in vivo. THC was found to be effective against experimental glioma, liver, pancreatic, breast and lung cancer while CBD showed activity against glioma and neuroblastoma, melanoma, colon, breast, prostate and lung cancer. Further in vitro and in vivo studies also greatly support their use in combination with traditional chemotherapy or radiotherapy, which results in improved efficiency, attenuated toxicity or reduced drug resistance.
Taken together most of available preclinical results emphasize the extensive therapeutic potential of THC and CBD in various types of cancers. The potential clinical interest of cannabinoids is additionally suggested by their selectivity for tumor cells as well as their good tolerance and the absence of normal tissue toxicity, which are still the major limitations of most conventional drugs. The accumulated preclinical evidence strongly suggests the need for clinical testing of cannabinoids in cancer patients.”
“The Cannabis plant contains over 100 phytocannabinoids and hundreds of other components. The biological effects and interplay of these Cannabis compounds are not fully understood and yet influence the plant’s therapeutic effects.
Here we assessed the antitumor effects of whole Cannabis extracts, which contained significant amounts of differing phytocannabinoids, on different cancer lines from various tumor origins.
Our results show that specific Cannabis extracts impaired the survival and proliferation of cancer cell lines as well as induced apoptosis.
Our findings showed that pure (-)-Δ9–trans-tetrahydrocannabinol (Δ9-THC) did not produce the same effects on these cell lines as the whole Cannabis extracts. Furthermore, Cannabis extracts with similar amounts of Δ9-THC produced significantly different effects on the survival of specific cancer cells.
In addition, we demonstrated that specific Cannabis extracts may selectively and differentially affect cancer cells and differing cancer cell lines from the same organ origin. We also found that cannabimimetic receptors were differentially expressed among various cancer cell lines and suggest that this receptor diversity may contribute to the heterogeneous effects produced by the differing Cannabis extracts on each cell line.
Our overall findings indicate that the effect of a Cannabis extract on a specific cancer cell line relies on the extract’s composition as well as on certain characteristics of the targeted cells.”
“Many previous reports highlight and demonstrate the anti-tumor effects of cannabinoids. In the last decade, accumulating evidence has indicated that phytocannabinoids might have antitumor properties. A number of in vitro and in vivo studies have demonstrated the effects of phytocannabinoids on tumor progression by interrupting several characteristic features of cancer. These studies suggest that specific cannabinoids such as Δ9-THC and CBD induce apoptosis and inhibit proliferation in various cancer cell lines.”