Scientists may have found cancer's 'Achilles heel'
Published Friday, March 4, 2016 10:56AM EST
Last Updated Saturday, March 5, 2016 11:45AM EST
An international team of researchers believes it has made an important discovery about the genetics of cancer tumours that they say could offer a new way to deliver customized cancer-killing therapies.
The team said their research, published in the journal Science, would help to fine-tune the way existing immunotherapy drugs are used on the most complex cancers, such as melanoma and lung cancer.
Immunotherapy -- currently one of the most promising areas of cancer research -- uses specific proteins to try to stimulate the body’s immune system to recognize tumours as “foreign agents.” The immune system then goes after these tumours, destroying them while leaving healthy cells alone.
Such treatments help get around one of the key problems that can make cancer so difficult to treat. Many tumours are able to deactivate the body’s T-cells, which are the soldiers of the immune system, detecting bad cells and destroying them.
As well, cancer tumours mutate as they grow so that they are never made up of one kind of cell. Instead, they are a mixture of many kinds of rogue cells that can behave very differently from one another, evading the treatments used to target them.
But now researchers from Harvard, MIT and University College London, have found that even as tumours mutate, they still produce distinct “flags,” or antigens, which appear on the surface of all the tumour’s cells.
Finding these unique flags within a tumour is the equivalent of finding the cancer’s "Achilles heel,” the team says.
The finding is important, they add, because it is not enough to simply alert the immune system to a particular antigen in a tumour. The antigen has to be present on all the tumour cells; otherwise, treatment might leave some cells unharmed, allowing the tumour to begin growing again.
Study co-author Prof. Charles Swanton, from the University College London’s Cancer Institute, says the findings pave the way for treatments that would activate T-cells to target and attack all tumour cells at once.
“This opens up a way to look at individual patients’ tumours and profile all the antigen variations to figure out the best ways for immunotherapy treatments to work, prioritizing antigens present in every tumour cell and identifying the body’s immune T-cells that recognize them,” he said in a statement.
So far, the team has not yet tried using their findings to treat live patients, but they say their findings could lead to more precise, personalized treatments. Swanton told The Guardian his team hopes to launch a study in lung cancer patients in the next two to three years.
“It’s incredibly exciting,” Swanton said in a statement, “and although it’s early days, it offers hope that we might just be able to turn the tide against advanced cancer – something we desperately want for our patients.”
Sian Bevan Canadian Cancer Society’s Research Institute find this latest research “interesting,” saying the whole field of immunotherapy is exciting and provides lots of new opportunities for new treatments.
“The whole idea behind this work is to personalize the treatment depending on the different mutations in the tumours,” she told CTV News Channel from Toronto.
Cancer Research UK has produced an explanatory video, which can be found here.