An international team of scientists led by Peter MacCallum Cancer Centre has identified a new way to potentially stop cancer cells hiding from the immune system.
Their research has identified a master regulator of a protein (PD-L1), which is over-expressed by tumour cells, and which suppresses the immune response to these rogue cancer cells allowing them to proliferate.
“For some time we’ve known that PD-L1 plays an important regulatory role for our immune system – and when it is operating normally it is a handbrake that prevents over-reactions,” said Professor Mark Dawson, Head of the Translational Haematology Program at Peter Mac.
“We’ve also know that cancers exploit this process and an over-supply of PD-L1 on the surface of tumour cells effectively shields them, stopping them from being killed off by our immune system.”
“If we had a way to control the production of PD-L1 this would be a powerful new addition to our armoury of immunotherapy agents, and that’s what the research has identified.”
New protein target for immunotherapy
The researchers found the protein CMTM6 is needed to maintain the expression of PD-L1 and in a wide variety of cancers cells they showed that as CMTM6 levels decline so does the cancer’s ability to suppress the immune response.
The discovery opens a new avenue to develop immunotherapy drugs that target CMTM6. These would use the similar pathway as emerging “anti-PD1” class of antibody therapies, which have already shown great promise for the treatment of a broad array of cancers.
“If we can develop new drugs that re-activate a patient’s immune response to their cancer, this would be a major world-wide advance,” said Professor Joe Trapani, Executive Director of Research and Head of the 70-strong Cancer Immunology Program at Peter Mac.
“Immunotherapy is the first totally new treatment for advanced cancer in over 50 years and our capacity for this exciting research project and many more is rapidly expanding.”
A paper describing this work, titled “CMTM6 maintains the expression of PD-L1 and regulates anti-tumour immunity”, has been recently published in the journal Nature.
The study was funded by the National Health and Medical Research Council and other collaborators.
This post was originally published on Peter Mac’s website.
ACRF has supported cancer research at Peter Mac by providing three grants, totalling $7 million towards cutting edge research technology and equipment.