Researchers in Spain have discovered that a cannabis extract makes brain tumors shrink by halting the growth of blood vessels that supply the tumors with life. Cannabis has chemicals called cannabinoids, these are the chemicals that could effectively starve tumors to death, say the researchers.
The study was carried out at the Complutense University, Madrid, Spain.
The team used mice to demonstrate that the cannabinoids block vessel growth.
You can read about this latest research in the journal Cancer Research.
Apparently, the procedure is also effective in humans.
The Spanish team, led by Dr Manuel Guzm�n, wanted to see whether they could prevent glioblastoma multiforme cancer from growing by cutting off its blood supply. Glioblastoma multiforme is one of the most difficult cancers to treat – it seldom responds to any medical intervention, such as radiotherapy, chemotherapy and surgery.
The scientists knew that cannabinoids will block the growth of blood vessels (to tumors) in mice – they wanted to find out whether the same thing would happen with humans.
The mice were given a cancer similar to the human brain cancer (glioblastoma multiforme). The mice were then given cannabinoids and the genes examined.
The genes associated with blood vessel growth in tumors through the production of a chemical called vascular endothelial growth factor (VEGF) had their activity reduced.
Cannabinoids halt VEGF production by producing Ceramide. Ceramide controls cell death.
Dr Guzm�n said: “As far as we know, this is the first report showing that ceramide depresses VEGF pathway by interfering with VEGF production.”
They then wanted to see if this would also happen with humans.
They selected two patients who had glioblastoma multiforme and had not responded to chemotherapy, radiotherapy or surgery. The scientists took samples from them before and after treating them with a cannabinoids solution – this was administered directly into the tumor.
Amazingly, both patients experienced reduced VEGF levels in the tumor as a result of treatment with cannabinoids.
The researchers said that the results were encouraging. In order to be sure about their findings they need to carry out a larger study, they said.
Dr Guzm�n said “The present findings provide a novel pharmacological target for cannabinoid-based therapies.”