Cancer's Achilles heel: Immunotherapy breakthrough as scientists discover 'flag' to target tumours

A ground-breaking technique that hunts out cancer cells using the patient's own immune system has been hailed as a revolutionary way to treat cancer.

A team from University College London has discovered that on the surface of every cell in a patient's tumour is a biological "flag" and also immune "killer" cells that can target that flag. In effect, they say it is the disease's "Achilles heel".

Their research has shown that patients could receive bespoke vaccines made from proteins from their own tumours that can spark the immune system to fight the cancer.

This would mean that healthy tissue would not be targeted and could work well against fast-mutating forms of the disease like lung cancer, although there is hope it could work on all forms of the disease.

Charles Swanton, from the UCL Cancer Institute told The Times: "I will be disappointed if we haven't treated a patient within two years." Peter Johnson, from Cancer Research UK, which funded the research told the newspaper: "We have big optimism about what it will deliver."

The research which was published in the journal Science, highlights two possible future treatments.

One would be where doctors read the genome from a tumour biopsy and work out which flags are on the malignant cells. They can then use the immune cells inside the tumours that recognise these flags, replicate them in a lab and then inject them back into the patient.

The second treatment would see protein flags being used to create a vaccine to be injected into the body. It was likely that these treatments would be used in alongside existing drugs.

Bespoke treatment - but it won't be cheap

Cancer can become resistant to drugs as it evolves. It can also switch off T-cells which are the body's natural defences. But the researchers think they could reactivate the T-cells which would then attack the tumour.

Swanton said: "This is exciting. There was evidence that complex tumours with many mutations could increase the chance of the immune system spotting them; now we can prioritise and target tumour antigens that are present in every cell, the Achilles heel of these highly complex cancers.

"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, prioritising antigens present in every tumour cell and identifying the body's immune T cells that recognise them. This is really fascinating, and takes personalised medicine to its absolute limit where each patient would have a unique, bespoke treatment."

About 160,000 people die from cancer each year in the UK, half of which are from lung, bowel, breast and prostate cancer.

The research is still in its early stages and would require trials.

Swanton said that that the treatment was "not going to be cheap" but added: "Cancer care is already incredibly expensive. And what if you balance it against getting a patient back into the workplace in their mid-40s? I would hope we can do this in a very cost-effective way."