Worth Repeating: Marijuana Halves Lung Cancer Tumor Growth


Graphic: NORML Stash Blog

By Ron Marczyk
A 2007 study, performed at Harvard University (yes, that Harvard) by Anju Preet, PhD and the Division of Experimental Medicine, is further evidence that supports the study performed by Donald Tashkin, M.D. (reported in Toke January 27) originally published in 2005, indicating that THC appears not to start or promote lung cancer, and if anything, appears to slow or stop lung cancer.
In other words, THC, marijuana’s main active ingredient, appears to have anti-tumor effects!
Dr. Preet’s conclusion is that the THC is the main player in stopping cancer. Tetrahyrocannabinol appears to stop epidermal growth factor (EGF) released by lung tumors. EGF is used for angiogenesis (it’s a growth factor released by a tumor to encourage new blood vessel growth to feed it; this also allows the growth of the tumor and allows it to spread).
When mice (whose biological functions are identical to humans’ in many ways) were implanted surgically with human lung cancer cells which were allowed to start growing and then treated with THC for three weeks, the cancer tumors shrunk by 50 percent in weight, and there was a 60 percent reduction in the number of tumors in their lungs.

Photo: TheBongPlace

​Two caveats about this study:
1. This was only a phase 1 study, meaning that some interesting experimental results were uncovered, by one researcher, in one lab. It needs to be reproduced in a bigger study using the same procedures.  A Phase 2 study would check if this type of treatment would be safe in humans and in what dosages, and would ascertain any drastic side effects. Phase 3 would be human study involving three groups: Group A gets real THC, Group B the old treatment (chemotherapy), and Group C would receive a placebo.
2. This study was performed in an animal model only, and would need to be reproducible in humans who have lung cancer, in large numbers, to see if cancer can be halted. But there is enough evidence here, in my opinion, that definitely screams out for further research… But the U.S. federal government makes getting cannabis for doctors and researchers to study on such cancer patients near impossible, and this in my opinion is a crime.
As a Registered Nurse I have cared for cancer patients, mostly the inner-city poor, and watched them die. My perspective is thus substantially more ground level then you’ll get from Congress.
Worldwide, lung cancer is the most common cancer in terms of both incidence and mortality (1.35 million new cases per year and 1.18 million deaths), with the highest rates in Europe and North America.
Five-year survival rates for lung cancer are low, and chemotherapy has a very low success rate. THC can’t be patented and pharmaceutical companies would find it hard to make money on this possible treatment.
In addition, there is the political bias against cannabis. Marijuana as medicine still has not gone fully mainstream yet, and 2012 must be the year we fix this.
Think about this information the next time you hear about someone with cancer.  LEGALIZE CANNABIS IN 2012! LEGALIZE FREEDOM! 
The active ingredient in marijuana cuts tumor growth in common lung cancer in half and significantly reduces the ability of the cancer to spread, say researchers at Harvard University who tested the chemical in both lab and mouse studies.  
They say this is the first set of experiments to show that the compound, delta 9 tetrahydrocannabinol (THC), inhibits EGF-induced growth and migration in epidermal growth factor receptor (EGFR) expressing non-small cell lung cancer cell lines. Lung cancers that over-express EGFR are usually highly aggressive and resistant to chemotherapy.
THC, which targets cannabinoid receptors CB1 and CB2, is similar in function to endocannabinoids, which are cannabinoids that are naturally produced in the body and activate these receptors. The researchers suggest that THC or other designer agents that activate these receptors might be used in a targeted fashion to treat lung cancer.
“The beauty of this study is that we are showing that a substance of abuse, if used prudently, may offer a new road to therapy against lung cancer,” said Anju Preet, Ph.D., a researcher in the Division of Experimental Medicine.
Acting through cannabinoid receptors CB1 and CB2, endocannabinoids (as well as THC) are thought to play a role in variety of biological functions, including pain and anxiety control, and inflammation. Although a medical derivative of THC, known as Marinol, has been approved for use as an appetite stimulant for cancer patients, and a small number of U.S. states allow use of medical marijuana to treat the same side effect, few studies have shown that THC might have anti-tumor activity, Preet says. The only clinical trial testing THC as a treatment against cancer growth was a recently completed British pilot study in human glioblastoma.
In the present study, the researchers first demonstrated that two different lung cancer cell lines as well as patient lung tumor samples express CB1 and CB2, and that non-toxic doses of THC inhibited growth and spread in the cell lines. “When the cells are pretreated with THC, they have less EGFR stimulated invasion as measured by various in-vitro assays,” Preet said.
Then, for three weeks, researchers injected standard doses of THC into mice that had been implanted with human lung cancer cells, and found that tumors were reduced in size and weight by about 50 percent in treated animals compared to a control group. There was also about a 60 percent reduction in cancer lesions on the lungs in these mice as well as a significant reduction in protein markers associated with cancer progression, Preet says.
Although the researchers do not know why THC inhibits tumor growth, they say the substance could be activating molecules that arrest the cell cycle. They speculate that THC may also interfere with angiogenesis and vascularization, which promotes cancer growth.
Preet says much work is needed to clarify the pathway by which THC functions, and cautions that some animal studies have shown that THC can stimulate some cancers. “THC offers some promise, but we have a long way to go before we know what its potential is,” she said.
Editor’s note: Ron Marczyk will be bringing to your attention stories from the cannabis archives that are “Worth Repeating.”

Often, as stories are churned through the media’s 24-hour news cycle, good information flashes by and is lost. We aim to help correct that with “Wo
rth Repeating,” which will cover important cannabis stories that you may have missed.
Ron is a retired health education teacher who taught health ed and psych (drug/sex ed) to high school students for 20 years. He is an R.N. (emergency room) M.S. in cardiac rehab, and worked as a New York City Police officer for two years.
More to come from the “Worth Repeating” Cannabis Archives — this gets even better…  stay tuned.