14 DAY TRIAL // A new study carried out by an international team of immunologists, concluded that cannabis compounds trigger a suppression of the body's immune functions, and actually promote cancer growth.
“Cannabis is one of the most widely used drugs of abuse worldwide and it is already believed to suppress immune functions making the user more susceptible to infections and some types of cancer,” said Dr Prakash Nagarkatti from the University of South Carolina, and leader of the team.
“We believe the key to this suppression is a unique type of immune cell, which has only recently been identified by immunologists, called myeloid-derived suppressor cells, MDSCs.”
The team focused on cannabinoids – a group of components found inside the cannabis plant, which include THC (delta-9 tetahydrocannabinol), a compound used for medical purposes like pain relief.
The analysis showed that even if most immune cells fight against cancers and infections to protect the body, MDSCs efficiently suppress the immune system.
Cancer patients have a high amount of these cells, and many doctors believe that MDSCs may suppress the immune system against cancer therapy, and promote cancer growth.
What Dr Nagarkatti's team managed to prove, was that cannabinoids trigger a significant amount of MDSCs, by activating the cannabinoid receptors.
This research is actually the first one to discover that marijuana cannabinoids can suppress the immune system by activating these unique cells.
“These results raise interesting questions on whether increased susceptibility to certain types of cancers or infections caused from smoking marijuana results from induction of MDSCs,” Nagarkatti said.
“MDSCs seem to be unique and important cells that may be triggered by inappropriate production of certain growth factors by cancer cells or other chemical agents such as cannabinoids, which lead to a suppression of the immune system's response.”
Dr Nagarkatti added that “marijuana cannabinoids present us with a double edged sword.
“On one hand, due to their immunosuppressive nature, they can cause increased susceptibility to cancer and infections.
“However, further research of these compounds could provide opportunities to treat a large number of clinical disorders where suppressing the immune response is actually beneficial.”
In another study, related to this work, Dr Christian Vosshenrich from the Pasteur Institute in Paris, found that when cancer cells grow, they produce interleukin-1 β (IL-1β), a molecule that also triggers MDSCs.
Both researches were published in the European Journal of Immunology.