A new treatment strategy for those experiencing breast cancer relapse could help save many lives.
Triple-negative breast cancer (TNBC) is one of the most difficult and aggressive forms of breast cancer, affecting around 15pc of all breast cancers diagnosed.
Occurring frequently in younger women, TNBC, unlike other forms of breast cancer, has no targeted therapies. Right now, the only treatment available is chemotherapy. While initially successful, a large number of patients will relapse after one to three years.
However, a new breakthrough achieved by scientists from the Apoptosis Research Centre at NUI Galway could drastically improve the chance of preventing TNBC relapse.
Until now, the exact mechanism of the tumour relapse post-chemotherapy was a mystery but, in a paper published to Nature Communications, the researchers have shown that it lies in IRE1.
This cellular stress sensor normally acts to alleviate short-term stress within cells, such as a lack of nutrients or oxygen. But when it comes to TNBC, chemotherapy was found to activate IRE1, leading to the production of survival glands that are pumped out of the cell to bolster the growth of new cancer cells.
A winning combination
For the sake of the patient, the research showed that relapse can be halted by specifically inhibiting IRE1 using a very specific small molecule drug.
In testing, the drug named MCK8866 was shown to reduce the production of these signals and, in turn, reduce the growth of new cancer cells by 50pc.
In a pre-clinical model of TNBC, the drug increased the effectiveness of chemotherapy treatment, leading to regression in eight out of 10 cancers compared to regression of just three in 10 cancers using chemotherapy alone.
This means that by combining chemotherapy with this IRE1 inhibitor, it could offer substantial benefits to those with TNBC and ensure they have a much lower chance of relapsing.
Dr Susan Logue, first author of the study, said: “While further research is needed, this work is a great example of how curiosity-driven basic research can lead to translational outcomes with real potential to impact on patient treatment.”