Cannabis Compounds may Inhibit Prostate Cancer

Early evidence suggests that compounds in marijuana called cannabinoids may help prevent prostate cancer cells from growing.

Researchers tested the anticancer effects of two cannabinoids: methanandamide and JWH-015. The compounds stopped the growth of therapy-resistance human prostate cancer cells in the laboratory and significantly reduced the size of prostate tumors in mice.

According to the authors, the cannabinoids may work by blocking tumor cell receptors, thereby preventing them from multiplying.

Although these preliminary results are promising, additional research is needed to fully understand how cannabinoids may affect prostate cancer in humans.

In a related April 2009 study, researchers found that tetrahydrocannabinol (THC), the main active component in marijuana, may help kill brain cancer cells. THC caused the tumors to shrink in both the mice and humans. They also noted that THC caused the tumor cells to undergo autophagy, or self-destruction.

For more information about marijuana, please visit Natural Standard’s Foods, Herbs & Supplements database.

Comments

[Kelly]

I think it is great that we are finally taking advantage of all the cannabinoid receptors throughout the body. These receptors are thought to be the most plentiful receptors in the brain, yet drugs are hardly ever made/used that target these receptors. The only drug on the market now is dronabinol (Marinol), and it is used to suppress severe nausea and vomiting and to increase appetite in patients with AIDS or cancer.

[Ryan]

I think that medications aren’t developed that target cannabinoid receptors more often because scientists are not fully aware of the function of these receptors throughout the body. Cannabinoid receptors are not only found in the brain, but also in the immune system, lungs, liver, kidneys and endothelium. Thus, stimulating one receptor for medicinal purposes may trigger a lot of unwanted side effects via multiple receptor stimulation all over the body.

[Tyler]

Columbia University recently did a study that revealed that marijuana contains up to 50% more carcinogens in its smoke than cigarettes, yet marijuana has a smaller lung cancer risk than cigarettes. Researchers suspected that this is due to the presence of a compound called THC (tetrahydrocannabinol) found in marijuana. THC apparently causes cell death to occur in cells that have mutated, thus reducing tumor growth. I wonder if this is the same mechanism that researchers are using to inhibit prostate cancer.

[Pam]

I have also heard of stimulating cannabinoid receptors for the treatment of breast cancer. Has anyone else heard about this too?

[Tod]

According to the American Cancer Society, prostate cancer has a 5-year survival rate of nearly 100% and a relative 10-year survival rate of 91%. It must be noted that survival rate obviously could vary depending on patient’s personal diagnosis (i.e., stage II vs. stage IV). I think with prostate cancer being one of the more treatable cancers, additional research in the field can possibly result in absolute cure.

[Ann]

My impression is that cannabis treatment for breast and prostate cancer remains controversial. I believe that some studies have shown benefit, while other studies have shown that some cancer strains are resistant to THC’s anti-tumor effects. While still in other studies, tumor growth has been accelerated via increased cell proliferation due to canabinoid-induced immunogenicity inhibition –- meaning that cannabis inhibits the body’s ability to recognize tumors as foreign, and therefore, the body does not illicit an immune response to them. There is a great article that goes into further detail in the British Journal of Pharmacology called “Cannabinoids and cancer: pros and cons of an antitumour strategy.”

[Jessica]

I think that cannabinoid-based cancer therapies are a wonderful idea. Most of the current anticancer drugs are very toxic and have a lot of side effects, whereas cannabis is sometimes used to treat side effects from anticancer drugs. If cannabinoid-based therapies were proven effective in prostate or breast cancer, its side-effect profile would be much more tolerable. In addition, usually anticancer therapies consist of a drug cocktail of 2-3 drugs, thus if a cannabis-based product could be used in these cocktails, it could even help treat and prevent the fatigue, pain and nausea/vomiting that accompany other drugs in the cocktail. This is very exciting news in the anticancer drug avenue!

[abg]

I wonder if cannabinoids will have any effect on the prevention of cancer in people who are at risk or in remission. Tyler commented in his post that a study from Columbia Univ. showed that marijuana was associated with a lower risk of small cell lung cancer. Maybe there is a difference between how THC is delivered to the system and what type of cannabinoid receptor it is.

[abg]

I read a news article from February 2009 on the Natural Standard Web site about a study linking marijuana use to testicular cancer. But this study showed that men aged 18-44 diagnosed with testicular cancer were 70 percent more likely to be current marijuana smokers. We are still learning about cannabinoid receptors and where they are in the body, and the difference between marijuana smoke and the THC extract. I’m interested in seeing if the information from these studies can be combined into a larger-scale study to see what types of cancer are affected by marijuana smoking and/or THC.

[Lo]

There is one thing I would be concerned about if this is developed as a drug and that is the drug’s abuse potential. If they are to be commercially available, it should be formulated in a way that it would be impossible to abuse the drug. This will ensure proper use of THC as a medication.

[luke]

I hope more research is done on specific receptor subtypes. JWH-015 is known to be 28 times more sensitive to the CB2 receptor than CB1. I wonder if this study made an conclusions or suggestions about whether methanandamide or JWH-015 had a greater impact on the results.

[Mike]

Prostate tumors can be of two types: malignant (cancerous) or benign (non-cancerous). Benign prostrate hypertrophy (BPH) is an abnormal growth of benign prostrate cells. Malignant tumors can spread and metastasize to other parts of the body like lymph nodes, bones, liver, colon and other organs. Some of the risk factors for prostate cancer are age, race, family history, high level of testosterone and obesity.

There are various ways it could be inhibited like surgery, radiation therapy, hormone therapy, chemotherapy and others. No direct connection between the use of cannabinoids and prostate cancer inhibition could be established from the information on Natural Standard monograph on prostate cancer. More evidence-based study will be needed before a strong correlation could be established between cannabinoids use in inhibition of prostate cancer.

[SK]

The research on cannabis compounds on prostate cancer inhibition suggests a therapeutic role for cannabinoids in cancer treatment. Currently, the only medicinal uses of cannabinoids (although controversial) is for nausea, pain and appetite stimulation in cancer patients.

Although this study shows promise in the laboratory, there are many issues when applying these findings to a clinical setting. Future clinical trials will have to determine the therapeutic index, safety and efficacy profile of these cannabis compounds. The future trials will also have to determine the correlation of PSA levels and when to initiate therapy.

[Eve]

In response to the Columbia University article brought up by Ryan -- it is very interesting that cigarettes have more lung cancer risk when they have 50% less carcinogens than marijuana. I wonder if these two products have the same type of carcinogens, or there might be one or more specific ones in cigarettes that are more harmful? But I do think there's a possibility that cannabinoids in marijuana might have some inhibitory effects on cancer cells. I would be interested in more research evidence that looks at the mechanism of action of these cannabinoids.

[Liam]

This recent research about cannabis compounds treating prostate cancer sounds promising, but it shouldn’t get blown out of proportion. The data suggest that these compounds may be able to stop the growth of cancerous prostate cells, but there doesn’t seem to be much data about it reversing any abnormal growth.

Prostate cancer is a slowly progressing disease, and the majority of patients are 65 years or older when they are diagnosed. Not to sound like a pessimist, but if these cannabis compounds will only slow disease progression of an already slowly progressing disease, how useful will they really turn out to be? Noticeable symptoms usually aren’t produced until later stages when the cancer has moved to other areas besides the prostate. More research is needed to determine what effects cannabis has on cancer cell growth in different tissues of the body before we can explore its potential for treating later-stage cancers.

[Sasha]

Good news for prostate cancer patients. I read a Polish study just last month that looked at marijuana derivatives as a promising therapy in the field of dermatology. The authors note that there are more than 60 such substances in this group, many of which have been used for hundreds of years by practitioners of natural medicine. Given this, it seems likely that we’ll continue to see more promising uses for THC down the road.

[Clayton]

The obvious hesitation about exploring the use of cannabis compounds for treating prostate cancer (and other cancers) is the abuse potential. Researchers know the mechanism of action involves cannabinoid receptors, so it may be possible to explore a sublingual formulation that contains an agonist and an antagonist compound, similar to how Suboxone works on opioid receptors. Prescribers have to get a special license to dispense Suboxone, and employing the same restrictions would most likely help decrease the abuse potential of cannabis compounds.

[Tim]

Prostate cancer can be a very scary diagnosis for a patient. it’s hopeful to see that all avenues of medicine, including natural medicines like marijuana, are being looked at to find an answer. Unfortunately, these results have only been seen in preliminary studies in mice prostate tumors. Let’s hope the results carry over to human prostate cancer cells.

[Shannon]

The media fuss about increasing abuse potential opportunities if cannabis compounds are developed for cancer treatment seems over the top. Shouldn’t we be exploring any avenue that shows promise in treating any type of cancer? Drug development can be approached in two different ways. First, a specific drug target (i.e. a certain protein) can be targeted and thousands of different compounds can be screened --- cannabis being one of them. Second, a specific compound (i.e. cannabis) can be targeted and thousands of different targets (i.e. different proteins) can be screened to see if the compound has an effect anywhere. I think a compound-target approach should be used when exploring cannabis therapy options. There are thousands of different enzyme assays already developed that cannabis can be screened through, so what are we waiting for?

[Andy]

Did anyone else notice the article that Natural Standard posted in February 2009 that showed a potential link between cannabis and testicular cancer? I find it very intriguing that although the use may increase the risk testicular cancer, two compounds may help to treat prostate cancer. It just goes to show you how diverse the cannabinoids are and supports that we need to keep researching all of the possibilities that could come from this one little plant.

[T.K.]

Our knowledge of cannabinoids and their effects is in its infancy. Endogenous cannabinoids and their receptors were just discovered in the human body in the 1980s, and we are just now beginning to evaluate their effects. It is interesting that cannabinoids are meant to be processed within our bodies considering the finding of cannabinoid receptors. This may suggest that the effects are more natural than the effect of analgesics that rely on opioid receptors.

From the limited data available, their effects are seen to be both immediate and delayed; acting somewhat as a neurotransmitter and a hormone at the same time. The plant marijuana contains over 50 different cannabinoids, and until the effects of these substances are isolated, our knowledge will remain primitive.

Our attempts at creating synthetic cannabinoids have been relatively ineffective. Marinol has been reported to have inconsistent effects because of the variability of its availability to the tissues. Being committed to developing advances in healthcare, the subject of herbals and homeopathics cannot be overlooked. Some of the most used medications in this country were derived from plant sources, yet an entire family of medications may be available to us that we have long been reluctant to study.

[Nate]

Although concerns over the abuse potential of these cannabis compounds were mentioned earlier, I am sure the manufactured drug will be strictly regulated once on the market. Drugs that are controlled substances have many rules surrounding them before they are dispensed to a patient. Also, since the medical condition of prostate cancer is not strictly based on subjective parameters (such as pain), the marijuana substances may not be as abused as much as opiods are for pain. However, it will still probably take a longer time before such a drug is approved since it will introduce another potential threat of medication drug abuse and addiction in the community.

[Sweetbanana]

Does anyone wonder why marijuana grows so ferociously? Its presence and ubiquity demands respect; it is an herb to be reckoned with. Early ancient scholars and wise men have praised Cannabis as a panacea or a cure all and have rated it as a top medicine. With more than 400 chemicals, including steroids and vitamin A, its wide use has been explored in the treatment fo AIDS, cancer, dystonia, glaucoma, depression, multiple sclerosis, asthma, migraine headaches, pruritus, epilepsy and severe pain.

The New English Dispensatory of 1764 recommended burning hemp root and applying it to the skin to reduce inflammation. Also, a marijuana concoction has been used to dry tumors and dissolve deposits in the joints.

As there are different reviews about the activities of cannabinoids, such as THC, as potential cancer-fighting agents, a cohort study that looks into early cannabis use in men with prostate cancer and survival rate will be very much enlightening. Also, a long-term epidemiologic study that compares men who are using cannabis to those who aren't and their chances of getting prostate cancer will shed more light on the selectivity of cannabinoids.

[Estelle]

This study evaluating the effects of cannabinoids on the human tumor prostate cell (PC3) is quite interesting. I would have to agree with many of you who have stated that more research is needed. However, I feel this is a great pathway to investigate since cancer treatments are incredibly toxic with numerous side effects. If this agent, a natural substance, proves to have some beneficial effects on the progression of prostate cancer, that would be a huge step in the cancer realm. In terms of increased risk of testicular cancer associated with marijuana use, perhaps future studies will investigate what compounds are associated with that risk.

[karina gordin]

Considering all the medicinal benefits of marijuana, I wonder what the best method of administration is. Smoking? Tincture, tea or capsule form? Perhaps homeopathic proportions are optimal? Is the bioavailability rapid or slow; moreover, stunted or stimulated by food?

Because the research is extensive, I decided to focus on the rapid absorption method associated with smoking and how that process affects us physiologically.

In one study, researcher Donald Tashkin, MD, of UCLA’s David Geffen School of Medicine, suggests that while a demonstrative increase in cancer risks was noted among cigarette smokers in the study, no such association was noted in regular cannabis users. In fact, there was no significantly greater risk for very heavy, long-term marijuana users who smoked more than 22,000 joints over a lifetime than infrequent marijuana users or nonusers.

This is quite surprising because it was found that there are just as many, if not more, carcinogens and co-carcinogens in marijuana smoke than in cigarettes! Essentially, the key must be that marijuana smoke also contains cannabinoids such as THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol), which are non-carcinogenic and demonstrate anti-cancer properties in vivo and in vitro.

Upon delving further into the most popular method of marijuana consumption, which is smoking, I found that the smoke promotes the development of pre-cancerous changes in bronchia and epithelium cells in similar rates to cigarrete smokers. Ultimately, the solution for cannabis users who require the rapid onset of action associated with inhalation, but do not tolerate the noxious smoke, can dramatically reduce their intake of carcinogenic compounds by availing themselves in vaporization, rather than smoking. "Our results show that with the Volcano [vaporizing device], a safe and effective cannabinoid delivery system seems to be available to patients,"investigators at Leiden University's Institute of Biology concluded.