cannabisnews.com: Marijuana May Stall Brain Tumor Growth





Marijuana May Stall Brain Tumor Growth
Posted by CN Staff on August 14, 2004 at 22:27:59 PT
By Jennifer Warner, WebMD Medical News  
Source: WebMD
The active ingredient in marijuana may help fight brain tumors, a new study suggests. Researchers say the cannabinoids found in marijuana may aid in brain tumor treatment by targeting the genes needed for the tumors to sprout blood vessels and grow. Their study showed that cannabinoids inhibited genes needed for the production of vascular growth factor (VEGF) in laboratory mice with glioma brain tumors and two patients with late-stage glioblastoma multiforme, a form of brain cancer.
VEGF is a protein that stimulates blood vessels to grow. Tumors need an abundant blood supply because they generally grow rapidly. So when VEGF is blocked, tumors starve from lack of blood supply and nutrients. Blocking of VEGF constitutes one of the most promising tumor-fighting approaches currently available, says researcher Manuel Guzman, professor of biochemistry and molecular biology, at the Complutense University in Madrid, Spain, in a news release. Guzman says the findings suggest VEGF may be a new target for cannabinoid-based treatments. Previous studies have shown that cannabinoids could inhibit the growth of tumor-associated blood vessels in mice, but until now little was known about how they worked. The results of the study appear in the Aug. 15 issue of the journal Cancer Research. Cannabinoids May Help Starve Tumors In the study, researchers looked at the effects of cannabinoid treatment on gliobastoma multiforme, a form of brain cancer that affects about 7,000 Americans each year. It's considered one of the deadliest forms of cancer and usually results in death within one to two years after diagnosis. Treatment typically involves surgery, followed by radiation and/or chemotherapy. But despite these efforts to destroy the tumor, this type of brain tumor often survives and starts growing again, which is why researchers are looking for novel ways to attack it. In order to grow, all tumors require a network of blood vessels to feed them, and they create this network through a process known as angiogenesis. VEGF is critical to this process. In the first part of the study, researchers induced brain cancer in mice and then treated them with cannabinoids. They then analyzed the genes associated with the growth of blood vessels in the tumor and found that cannabinoids inhibited several of the genes related to VEGF. In the second part of the study, researchers injected cannabinoids into tumor samples taken from two human glioblastoma patients. "In both patients, VEGF levels in tumor extracts were lower after cannabinoid inoculation," says Guzman. Researchers say more study is needed but the results suggest that cannabinoid-based therapies may offer a new alternative for treatment of these otherwise untreatable brain tumors. SOURCES: Blazquez, C. Cancer Research, Aug. 15, 2004; vol 64: pp 5617-5623. News release, American Association for Cancer Research. Note: Active Ingredient in Marijuana Inhibits Cancer Growth in Early Study.Reviewed By Michael Smith, MD on Friday, August 13, 2004 Source: WebMD (US)Author: Jennifer Warner, WebMD Medical News Published: August 15, 2004 Copyright: 2004 WebMD Inc.Contact: Sswint webmd.net Website: http://www.webmd.com/Related Articles:Cannabis Hope for Brain Cancerhttp://cannabisnews.com/news/thread19338.shtmlMarijuana Ingredient Inhibits VEGF Pathwayhttp://cannabisnews.com/news/thread19337.shtmlCannabis Extract Shrinks Brain Tumourshttp://cannabisnews.com/news/thread19336.shtml'Cannabis' Brain Tumour Drug Hopehttp://cannabisnews.com/news/thread19335.shtml
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Comment #10 posted by greenmed on August 21, 2004 at 12:17:45 PT
my two cents...
If inhibition of the VEGF pathway by cannabinoids proceeds through the standard cannabinoid action - binding of THC to CB1 or CB2 receptors, then angiogenesis would be expected to be suppressed only locally where there are receptors (and possibly only in the presence of specific cancer-activated genes). As there are no CB receptors in cardiac tissue, THC at any level would not be expected to have negative impact on angiogenesis there.Cannabis vaporization or eating would be a healthy option for cardiac patients - considering that smoking any combustible increases blood CO and CO2 concentrations, and lowers O2 availability.
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Comment #9 posted by CorvallisEric on August 16, 2004 at 23:19:51 PT
charmed quark (comment #6)
Just feel like repeating some really important things you said.... the medicinal properties of cannabis are not indicative that it is innocuous - in some cases it means it is less innocuous. The ideal recreational drug would have no medical properties beyond achieving the mental state people are after.That said - I think that cannabis is one of the safest drugs available to treat many medical conditions and probably is quite safe for normal recreational use compared to other recreational drugs. -PeteBravo!
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Comment #8 posted by breeze on August 16, 2004 at 22:03:52 PT
charmed quark
Sorry, didn't mean to sound so acidic- but 'tis true about people aren't health concious. In other nations, people live everyday likes it is their last day on earth. IN this nation, people live like there is ALWAYS a tommorow, and they don't give a shit about today, or what/how they do/don't do today effects tommorow.
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Comment #7 posted by Hope on August 16, 2004 at 10:22:12 PT
Might as well say it
The stuff could even be good for a person!
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Comment #6 posted by charmed quark on August 16, 2004 at 05:22:22 PT
Breeze and all
You misunderstood what I'm getting at. People will argue that cannabis' anti-tumor properties means it is even more useful and safe and therefore should be decriminalized or something. I'm just pointing out that the medicinal properties of cannabis are not indicative that it is innocuous - in some cases it means it is less innocuous. The ideal recreational drug would have no medical properties beyond achieving the mental state people are after.That said - I think that cannabis is one of the safest drugs available to treat many medical conditions and probably is quite safe for normal recreational use compared to other recreational drugs. 
-Pete
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Comment #5 posted by FoM on August 15, 2004 at 20:25:42 PT
Related News Article from News-Medical.Net
Novel Pharmacological Target for Cannabinoid-Based Therapies News-Medical in Medical Study News Published: Sunday, 15-Aug-2004 
  
 
 
 Cannabinoids, the active ingredients in marijuana, restrict the sprouting of blood vessels to brain tumors by inhibiting the expression of genes needed for the production of vascular endothelial growth factor (VEGF). 
According to a new study published in the August 15, 2004 issue of the journal Cancer Research, administration of cannabinoids significantly lowered VEGF activity in laboratory mice and two patients with late-stage glioblastoma. "Blockade of the VEGF pathway constitutes one of the most promising antitumoral approaches currently available," said Manuel Guzmán, professor of biochemistry and molecular biology, with the Complutense University in Madrid, Spain, and the study's principal investigator. "The present findings provide a novel pharmacological target for cannabinoid-based therapies." Glioblastoma multiforme, the most aggressive form of glioma, strikes more than 7,000 Americans each year and is considered one of the most malignant and deadliest forms of cancer, generally resulting in death within one to two years following diagnosis. The disease is usually treated with surgery, followed by conventional radiation alone or in combination with chemotherapy. However, the main tumor often evades total destruction, surviving and growing again, eventually killing the patient. For this reason, researchers are actively seeking other therapeutic strategies, some of which might be considered novel. In this study, the investigators chose to work with cannabinoids which, in previous studies, have been shown to inhibit the growth of blood vessels, or angiogenesis, in laboratory mice. However, little was known about the specific mechanisms by which cannabinoids impair angiogenesis, or whether the chemical might do the same in human tumors. To answer the first part of the question, the scientists induced gliomas in mice, which were subsequently inoculated with cannabinoids. Using DNA array analysis, the team examined 267 genes associated with the growth of blood vessels in tumors and found that cannabinoids lowered the expression of several genes related to the VEGF pathway, critical for angiogenesis. The researchers also discovered that cannabinoids apparently worked by increasing the activity of ceramide, a lipid mediator of apoptosis, resulting in the functional inhibition of cells needed for VEGF production. The ability of cannabinoids to alter VEGF production was significantly stifled following the introduction of a ceramide inhibitor. "As far as we know, this is the first report showing that ceramide depresses VEGF pathway by interfering with VEGF production," according to Guzmán. To answer the second part of the question relating to clinical tests, the scientists obtained tumor biopsies from two patients with glioblastomas who had failed standard therapy, including surgery, radiotherapy and chemotherapy. The biopsied tissue was analyzed before and after local injection of a cannabinoid. "In both patients, VEGF levels in tumor extracts were lower after cannabinoid inoculation," said Guzmán. The results, he added, suggest a potential new approach toward the treatment of these otherwise intractable brain tumors. "It is essential to develop new therapeutic strategies for the management of glioblastoma multiforme," the scientists wrote, "which will most likely require a combination of therapies to obtain significant clinical results." http://www.aacr.org/
 
 
http://www.news-medical.net/?id=4071
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Comment #4 posted by Nuevo Mexican on August 15, 2004 at 08:56:09 PT
Thank you Breeze, I concur!
My thoughts exactly!
Glad you stated your opinion so elequently!
Life is a risk, but living under bush is more life threatening to all of the human race, than any substance previously known to man. No one can argue that!
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Comment #3 posted by breeze on August 15, 2004 at 06:36:02 PT
Growth of new blood cells
Considering the fact that people aren't exactly health concious in every aspect of what they do during life, it should have zero impact on recreational users whatsoever, only in the propaganda aspect. Did you have caffeine in the last few hours? Did you have alcohol in the last week, there is no telling how many brain cells you killed if you did. Did you consider the possibility of becoming permanently disabled, maybe even dying, because you decided to drive your automobile to the market instead of walking- but then again, you could have been run down by a wreckless driver. And experts say that walking is one of the best exercises one can do. Eating a healthy diet is key to living longer and healthier- but take a look at the number of fast food resturants in your town- have you been there lately?Face it, something, somewhere, somehow- is GOING to kill you. You have no choice in the matter, no matter how hard you try to avoid it- it is inevitably going to happen. It will certainly be tragic and sad. I just don't want to be there when it happens to me.=) 
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Comment #2 posted by charmed quark on August 15, 2004 at 05:59:26 PT
Possible good news for cancer sufferers but ...
Not necessarily good news for recreational users. You probably don't want to use a drug recreationally that may supress the growth of new blood vessels. Think of middle-aged men and the bood supply to their hearts. However, the quantity used by most recreational users is probably low enough not to have a dramatic effect. Something to check out.-Pete
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Comment #1 posted by FoM on August 14, 2004 at 22:42:15 PT
Related Article from The Sunday Herald UK
Cannabis May Block Growth of Brain Cancer By James Hamilton August 15, 2004Cannabis chemicals may provide a new way of treating deadly brain cancer.Scientists have shown that cannabinoids – the chemicals responsible for the drug’s “high” – deter the growth of blood vessels which feed the tumour.They appear to prevent genes making a protein called VEGF (vascular endothelial growth factor) that stimulates the sprouting of blood vessels.Cutting off tumours’ blood supply is one of the latest anti-cancer strategies being explored by scientists. In studies cannabinoids significantly reduced the activity of VEGF in laboratory mice.They also lowered VEGF levels in tumour tissue samples taken from two patients with glioblastoma multiforme, the most lethal brain tumour type.About 4400 new cases of brain tumour are diagnosed in the UK each year. A small percentage of these are grade four gliomas, the most aggressive and dangerous brain tumours.Only about 6% of people diagnosed with these high- grade cancers live for more than three years. The disease is normally treated with surgery, followed by radiotherapy and possibly chemotherapy. But the main tumour often evades complete destruction and grows again to kill the patient.Cannabinoids had previously been shown to inhibit the growth of blood vessels in mice. But the mechanism involved remained a mystery and it was not known if the same effect occurred in humans.In the new Spanish-led study, cannabinoids were injected into mice with gliomas. DNA analysis was then carried out on 267 genes associated with the growth of tumour blood vessels. It showed that the cannabis compounds reduced the activity of several genes involved in VEGF production.Professor Manuel Guzman, from Complutense University in Madrid, said: “In both patients, VEGF levels in tumour extracts were lower after cannabinoid inoculation.” http://www.sundayherald.com/44079Copyright: Newsquest (Sunday Herald) Limited. 
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