Study by Barcelona scientists identifies key element for future treatment of breast cancer

As a result of medical research carried out by a team of scientists from Barcelona’s IRB, breast cancer patients face a higher chance of survival.

After conducting their study, the the Institute for Research in Biomedicine team identified how the MAF protein interacts with the oestrogen receptor, a key element in the development of breast cancer.

Roger Gomis, head of the Cancer Growth Control and Metastasis laboratory, and also a group leader at the Cancer CIBER (CIBERONC), explained: ‘This finding is a critical step in understanding how breast cancer spreads and opens up new therapeutic options for the 20 per cent of patients who cannot benefit from bisphosphonate treatment’.

What is the breast cancer survival rate?

Breast cancer is currently the most common disease among women, with more than 2 million new cases per year. Patients have a high survival rate, reaching around 90 per cent in the case of localised tumours. However, when there is dissemination of tumour cells and metastasis occurs, the prognosis worsens significantly.

About five years ago, the team of Barcelona IRB scientists verified that those patients with high levels of the MAF protein, which is found in the body in cells other than breast cells, have a greater risk of developing metastases, especially bone metastases.

Through Inbiomotion, a spin-off of IRB Barcelona and ICREA, they developed a test – named the MAF Test – that is already marketed in Spain.

What did their study discover?

It allowed them to certify that the accumulation of MAF was synonymous with a greater risk of metastasis. On the other hand, it also made it possible to identify those patients who can benefit from treatment with bisphosphonates.

Published in the journal ‘Nature Cell Biology’, the study revealed how it could help to prevent bone metastasis and those in whom this therapy, would not only be beneficial, but may worsen their prognosis.

As Gomis explained: ‘In four out of five patients, treatment with bisphosphonates is beneficial in preventing metastasis. However, in those patients who express high levels of MAF, this therapy is not effective, in fact, it induces metastasis. That means there are one in every five patients for whom we do not have an answer so far’.

With this in mind, Gomis and his team subsequently launched their latest study in an effort to understand the molecular bases of metastasis and figure out the mechanism by which patients with high levels of MAF were so metastatic.

What was the main conclusion of their study?

The main conclusion of this study – which was carried out in cultured cells and animal models and was validated in patient samples – was that: ‘MAF modifies chromatin through its interaction with the KDM1A enzyme’.

‘Following orders from MAF, it opens the DNA so that the oestrogen receptor can reach more sites and, therefore, go from binding to the usual number of sites of a tumour cell to do so to twice as many, making this “a bad cell, a very bad one”‘, said Gomis.

This knowledge now opens new perspectives in the treatment of breast cancer. Gomis explained that: ‘KDM1A is an enzyme and, therefore, we can attack it’.

‘There are drugs in Phase II that are used for other indications, such as multiple myeloma, with which we can block it’. If the efficacy of this inhibitor is finally confirmed: ‘we could respond to those 20 per cent of patients who cannot benefit from treatment with bisphosphonates’, he concluded.