Scientists from the UK believe they have found a way to ‘steer’ our immune systems to kill cancers.
The researchers at University College, London, whose work has been funded by Cancer Research UK, believe their discovery could form the backbone of new treatments, but the revolutionary method would be expensive and has not yet been trialled on patients.
The ‘Achilles heel’
The researchers have developed a way of finding unique markings within a tumour – its ‘Achilles heel’ – allowing the sufferer’s body to target the disease.
Experts said the idea made sense, but could be ‘more complicated in reality’. However, the researchers hope to test the technique on patients within two years. They believe by analysing the patient’s DNA, they will be able to develop working treatments.
People have tried to steer the immune system to kill tumours before, but cancer vaccines have largely failed. One explanation for this failure is that they are training the body’s own defences to go after the wrong target.
The major problem is that cancers are not made up of identical cells. Cancer cells are a heavily mutated, genetic ‘mess’, and samples at different areas within a single tumour can look and act very differently. The tumours grow like a tree with core ‘trunk’ mutations and other mutations which branch off in all directions.
The international study has developed a way of discovering the ‘trunk’ mutations that change the tumour’s antigens – the proteins that protrude from the surface of cancer cells.
Professor Charles Swanton, from the UCL Cancer Institute, said: “This is exciting. Now we can prioritise and target tumour antigens that are present in every cell – the Achilles heel of these highly complex cancers. This is really fascinating and takes personalised medicine to its absolute limit, where each patient would have a unique, bespoke treatment.”
There are currently two different approaches being suggested for targeting the trunk mutations.
The first of which is to develop cancer vaccines for each of the patients that trains their immune systems to spot the cancerous mutations.
The second approach is to ‘fish’ for immune cells that are already targeting those mutations and to increase their numbers in the lab, and then transfer them back into the body – ready to fight the cancerous tumours.
Could it help treat mesothelioma or asbestos related lung cancer?
Mesothelioma is a type of lung cancer caused, in the vast majority of cases, by exposure to asbestos dust and fibres. It is notoriously difficult to treat any kind of lung cancer and mesothelioma is incurable.
It is a rare cancer and attracts little funding for research, which is why the ‘Achilles heel’ research is exciting because it offers a hope to treat all types of cancerous tumours no matter where they are in the body.
Figures from the Health and Safety Executive show that more than 2,500 people are diagnosed with pleural mesothelioma in the UK each year and according to the Department for Health and Pensions, 53,000 people will die from pleural mesothelioma between 2013 and 2037.
Any development towards a wide spread treatment for cancers will come as welcome news for those suffering from, or affected by, mesothelioma or asbestos related lung cancer. It could be entirely possible for this new technique to allow scientists to instruct and steer antigens from immune systems towards the mesothelioma tumours in the pleura around a patient’s lungs.
The current focus of treatments for mesothelioma is to ease discomfort and pain caused by the cancer, attempt to stop the progress of the disease and, where possible, prolong survival and improve outcomes.
An expert from the Institute of Cancer Research, Dr Marco Gerlinger, has stated: “This is a very important step and makes us think about heterogeneity as a problem and why this gives cancer this big advantage.
“Targeting trunk mutations makes sense from many points of view, but it is early days and whether it’s that simple, I’m not entirely sure. Many cancers are not standing still, but they keep evolving constantly. These are moving targets which makes it difficult to get them under control. Cancers that can change and evolve could lose the initial antigen or maybe come up with smokescreens of other good antigens so that the immune system gets confused.”
There is still a long way to go.