Finding may help those at risk of breast cancer

Giving drugs usually administered in the late stages of breast cancer to healthy people with faulty genes could prevent them from developing the disease, a study has suggested.

The discovery could lead to people who are carriers of the BRCA mutation – which puts them at a higher risk of breast, ovarian and other cancers – being offered preventative treatment options other than surgery, researchers said.

It comes after academics from Cambridge University discovered immune cells in the breast tissue of healthy women carrying faulty BRCA1 or BRCA2 genes showed signs of a malfunction known as exhaustion.

This mechanism, usually found in late-stage tumours, suggests the immune cells cannot clear out damaged cells, which eventually leads to cancer.

Senior author Professor Walid Khaled, of Cambridge University department of pharmacology and Wellcome-MRC Cambridge Stem Cell Institute, said immunotherapy drugs exist which block this function in the late stages of the disease.

He said: “We’re very excited about this discovery, because it opens up potential for a preventative treatment other than surgery for carriers of BRCA breast cancer gene mutations.

“Drugs already exist that can overcome this block in immune cell function but so far they’ve only been approved for late-stage disease.”

Immunotherapy helps the immune system recognise and fight cancer.

It can be administered on its own or alongside other treatments.

“No one has really considered using them in a preventative way before,” Prof Khaled added.

“However, these drugs do have serious side-effects and we are working now on testing these in pre-clinical models to determine a safe dosage before moving to human studies.”

According to the NHS, out of 100 women with a BRCA1 gene mutation between 65 and 85 will develop breast cancer in their lifetime while between 40 and 63 will develop ovarian cancer.

Out of 100 women with the BRCA2 mutation, between 40 and 85 will develop breast cancer at some point in their life.

In some cases, patients with the faulty genes may be offered risk-reducing surgery, which removes tissue such as breasts or ovaries that could become cancerous.

Cancer Research UK has granted the Cambridge research team with a Biology to Prevention Award to test the method in mice, and will closely monitor side-effects and dosage.

After this, a pilot clinical trial could be carried out in women with BRCA gene mutations.

Prof Khaled added: “The best way to prevent breast cancer is to really understand how it develops in the first place.

“Then we can identify these early changes and intervene.

“Late-stage breast cancer tends to be very unpredictable and hard to manage. As we make better and better drugs, the tumours just seem to find a way around it.”

Dr Simon Vincent, director of research, support and influencing at Breast Cancer Now, said: “The best weapon we could have against breast cancer is the ability to stop it occurring in the first place.

“This research, which used tissue samples from Breast Cancer Now’s Tissue Bank, suggests that we could prevent some women with altered genes from developing the disease by using drugs approved for treatment in the late stages of breast cancer.”