Understanding how breast cancer becomes resistant to PARP inhibitor drugs

Sometimes breast cancer can become resistant to treatments. This means the disease can keep growing, and could spread around the body.

PARP inhibitors are a treatment that breast cancer can become resistant to. But we don’t know how, as PARP inhibitors haven’t been around for long.

So, we need to find out. This will help us to find new treatment strategies, so that more people diagnosed with breast cancer can live, and live well.

PARP inhibitors are a type of targeted therapy that can treat breast cancers with an altered BRCA1 or BRCA2 gene. These cancers rely on a protein called PARP to repair their DNA and keep growing. PARP inhibitors work by stopping this process. 

But PARP inhibitors don’t work for every patient, and cancer cells can become resistant to them. Professor Nick Lakin, from the University of Oxford, wants to better understand why and to use this knowledge to find signs that breast cancer cells will respond to PARP inhibitors.

Nick and his PhD student also want to find new weaknesses in tumours that are resistant to PARP inhibitors. They’ll be using a variety of breast cancer cells grown in the lab to study this. They’ve already discovered some proteins that are involved with PARPs, and they’re working out if they could be targets for new breast cancer treatments.

This research will lay the foundations to predict whether someone’s cancer will respond to PARP inhibitors and potentially find new weaknesses in breast cancers that don’t respond to these drugs, so that we can develop new treatments.

The project could help thousands of people. Of the 55,000 women diagnosed with breast cancer every year in the UK, around 5 to 10% are caused by an altered gene. The most common altered genes are the BRCA1 or BRCA2 gene. They might not all be treated with PARP inhibitors. But it’s important that we know who will benefit from PARP inhibitors and who won’t, so that everyone can get the best possible treatment.