University of Alberta researchers have discovered an experimental combination drug therapy which dramatically shrinks tumours and prevents metastasis in mice, and could act as a new cancer therapy in the future.

Almost all cancer fatalities are caused by metastasis, the migration of tumour cells to a different site in the body, where secondary growths then develop.

In the study, two drugs were used together to ensure DNA damage in human breast cancer cells in mice was greatly increased, so the tumours had limited capacity to repair themselves. Following this, the scientists found the tumours shrank considerably, and metastasis was prevented.

Armin Gamper, an assistant professor of oncology at the University of Alberta, said that: “The combination was very well tolerated…If we see that this works as well in patients as it does in mice, at one point it might, at least in some cases, replace the traditional chemotherapy because it seems to have far fewer side-effects.”

The drugs involved in the combination are already being tested in clinical trials, on their own and in combination with other drugs, but not together. Because of this, the scientists said, the process of starting a new combined clinical trial will be greatly sped up.

From here, the scientists intend to expand their work to other cancer types and identify biomarkers for patients best served by the treatment.