11 October 2018
For the first time scientists working on the development of cancer therapies have won a Nobel prize. Dr James Allison, from The University of Texas, and Professor Tasuku Honjo, based at Kyoto University, have been awarded the Nobel Prize for Physiology or Medicine for their discovery of cancer therapy by using inhibition of negative immune regulation.
Dr Allison studied the mechanism of CTLA-4 and Professor Honjo, the action of PD-1. These are proteins that function as a brake on the immune system. They both realised the potential of releasing the brake and thereby allowing our immune cells to attack tumours.
As a direct result of the scientists’ work, cancer drugs have been developed which are beginning to revolutionise the treatment of previously difficult cancers such as melanoma, renal cancer and lung cancer. These are the agents known as ‘checkpoint inhibitors’. Ipilimumab exploits CTLA-4 inhibition to activate t-cells to attack melanomatous tumours. Nivolumab and Pembrolizumab target the PD-1 molecules on the surface of T cells in order to treat melanoma, non-small cell lung cancer and urothelial cancer.
Work is on-going to extend the use of existing agents into other tumour types and to develop new agents which utilise the same, or similar immunological pathways.