A treatment for one of the more hard to treat types of breast cancer could be a step closer thanks to the discovery by Irish based researchers of a potential new therapy.

The scientists have found that a new drug called THZ-1 is capable of halting the growth of triple negative breast cancer.

The researchers say that while use of THZ-1 in humans is still some way off and further study is necessary, the discovery does open up a wider range of new and less toxic treatment options.

"This study has uncovered an important new treatment possibility for patients with triple negative breast cancer, a particularly aggressive subtype of the disease," said Professor William Gallagher, the lead investigator on the study and Professor of Cancer Biology at UCD.

Triple negative breast cancer is a very challenging tumour type because it lacks three important proteins or biomarkers.

As a result, it is difficult to target existing therapies, like hormone based drugs such as Tamoxifen and Herceptin, at the tumour, leaving chemotherapy as the only viable treatment option.

A common problems though is that many patients with triple negative breast cancer find it is resistant to such treatments, leading to poor prognosis.

However, scientists at the Irish Cancer Society Collaborative Cancer Research Centre, BREAST-PREDICT, working as part of an EU-funded research consortium may have found a way around this problem.

They've established that a protein called CDK7 is abundant in triple negative breast cancers and those with such elevated levels are more likely to see the cancer return following chemotherapy.

As a result the researchers say CDK7 levels can be used to establish in advance whether patients are likely to react well or not to chemotherapy, allowing doctors to bypass the option and go straight to alternative treatments.

The scientists also found that the drug THZ-1 is capable of stopping triple negative breast cancer cells developed in the lab from growing further.

This was the case both when the drug was used on its own and when it was combined with other remedies.

The findings have recently been published in the journal Cancer Research.