Several studies have reported the health risks associated with the use of marijuana but new research has shown that pot can actually impact cancer tumors, significantly reducing their growth.

Researchers at the University of East Anglia and Universidad Complutense de Madridin, Spain, state that previously unknown signaling platforms in the main psychoactive ingredient in marijuana are responsible for the drug's success in shrinking tumors.

For the study, the researchers used samples of human cancer cells to induce tumors in mice. Following this, the team then targeted the tumors with doses of the cannabis compound THC (Tetrahydrocannabinol). They discovered that the two cell receptors in particular were responsible for the anti-tumor effects of the drugs. 

"THC, the major active component of marijuana, has anti-cancer properties. This compound is known to act through a specific family of cell receptors called cannabinoid receptors. However, it was unclear which of these receptors were responsible for the anti-tumour effects of THC," said Dr Peter McCormick from UEA.

He explained that the drug's effects were mediated through the joint interaction of CB2 and GPR55 – two members of the cannabinoid receptor family. "Our findings help explain some of the well-known but still poorly understood effects of THC at low and high doses on tumour growth. There has been a great deal of interest in understanding the molecular mechanisms behind how marijuana, and specifically THC, influence cancer pathology". 

Researchers have said that the pharmaceutical industry is trying to make synthetic equivalents that might have anti-cancer properties and that the study's findings regarding the receptors involved have provided a major step toward future development of therapeutics to reduce tumor growth.

However, Dr McCormick cautioned that cancer sufferes should not self-medicate. "Our research uses an isolated chemical compound – and using the correct concentration is vital. Cancer patients should not use cannabis to self-medicate. But I hope our research will lead to a safe synthetic equivalent being available in the future," he said.

A recent study of marijuana found that smoking pot can drastically exacerbate anxiety and depression.