Certain gene mutation 'hotspots' found in breast cancers can be beneficial and help patients survive longer, suggests new research.Kataegis -- the multiple mutations that cluster in a few hotspots in a genome -- occurs in nearly 55 per cent of breast cancers.The findings showed that kataegis is actually a positive marker in breast cancer and patients with these mutation hotspots have less invasive tumours, better prognoses as well as longer survival."The study found that kataegis is associated with a good prognosis for patients with breast cancer," said lead author Kelly Frazer, Professor at University of California San Diego.The mutation hotspots were found more common in breast cancer patients diagnosed at a later age and in patients with HER2-positive and high-grade tumours.Further, the genes located near kataegis hotspots were found less likely to behave abnormally than genes located further away in the genome."
We think kataegis mutations are dampening the abnormal expression of neighbouring genes that might otherwise contribute to tumour development and invasiveness," said Matteo D'Antonio, PhD, a postdoctoral researcher in Frazer's lab and first author of the study.The status of kataegis can help doctors determine the treatment options that might work best for patients with the mutation pattern, the researchers said.In addition, tumours with kataegis showed elevated levels of PLAC1, a gene that encodes a molecule that is an immunotherapy target in gastric cancer. However, "there's a long way to go before kataegis status could be used in the clinic," Frazer added.For the study, the team analysed the kataegis status of 97 breast tumours and then paired this information with patient data, such as age at diagnosis, treatment and outcome. Although the causes of death for patients in the study are not known, patients without kataegis tended to die younger (median age 47 years old) than patients with kataegis (median age 78 years old), said the paper published in the journal Cell Reports.