Marijuana may fight brain tumours

WASHINGTON: The main chemical in marijuana kills cancerous brain cells, offering hope for future anti-cancer therapies, say Spanish scientists.

A team led by Guillermo Velasco of Complutense University in Madrid, found that the active component of marijuana – tetrahydrocannabinol (THC) – kills tumour cells through a process called autophagy. This is the process that occurs when a cell self-destructs by digesting itself.

The research, which appears in the April edition of the Journal of Clinical Investigation, demonstrates that THC and related cannabinoids appear to be "a new family of potential anti-tumoral agents", the authors write.

Injecting THC

In the study the scientists conducted most of their research on mice, in which the growth of cancer was stimulated. But the researchers also looked at two patients suffering from a highly aggressive form of brain cancer who were enrolled in a clinical trial.

A mixture of THC in saline solution and injected it into each patient's tumour for 26 or 30 days, then the researchers took samples of the brain tumours. By analysing the tumours using electron microscopy, the researchers discovered that the cancer cells had been killed off while the normal cells stayed intact.

"Although these studies were only conducted in specimens from two patients," the researchers said, "they are in line with the preclinical evidence shown [in mice] and suggest that cannabinoid administration might also trigger autophagy-mediated cell death in human tumors."

Anti-cancer therapies

There have been previous studies that found cannabinoids curbed the growth of several types of tumours in rats and mice, but the mechanism by which is worked has been obscure until now.

Autophagy has a dual role in cancer: in some cases it promotes cancer cell survival and in other cases it inhibits cancer cell survival. This study identified the signalling route by which autophagy is activated for cell death.

The authors suggest that the study may prove useful in the development of future anti-cancer therapies based on THC or in the activation of the process that results in autophagy.

Study says marijuana chemical has anti-cancer properties

According to a study released on Thursday, Spanish researchers from the Complutense University in Madrid, together with scientists of other universities, found that tetrahydrocannabinol (THC) - the main chemical in the infamous narcotic agent, marijuana - likely helps the annihilation of brain cancer cells.

The research, which proposes to bring to improve the prospects of anti-cancer therapies, said that THC causes cancer cells to go through a process called autophagy - the breakdown that takes place when the cells fundamentally self-digest.

Based on the findings of the research, which was first carried out on the laboratory mice, and then substantiated on two patients - suffering from the highly aggressive and recurrent brain tumor, glioblastoma multiforme - in an experimental trial, the scientists came to the conclusion that THC and associated "cannabinoids" depicted properties of being "a new family of potential anti-tumoral agent."

The study which has been published in the April edition of the US Journal of Clinical Investigation, on of the scientists, Guillermo Velasco, reported: "We found that the anti-tumoral action of THC is based on its ability to activate an intracellular signalling pathway that promotes the activation of a cellular process called `autophagy'. The activation of this pathway leads to cancer cell death."