Australian researchers from Adelaide University and the Olivia Newton-John Cancer Research Institute have identified a novel molecular switch that drives the spread of aggressive tumors. Published in EMBO Molecular Medicine, the breakthrough study reveals that Australian researchers uncover a promising new way to tackle triple-negative breast cancer by restoring a critical regulatory molecule known as miR-342. The discovery opens new avenues to prevent life-threatening secondary cancers in organs such as the lungs and bones. Triple-negative breast cancer accounts for 10% to 15% of Australia’s approximately 21,000 annual breast cancer diagnoses but causes a disproportionate number of deaths. Lead investigators demonstrated that when miR-342 levels fall, a cancer-driving pathway called E2F becomes overactive, allowing dormant cancer cells to spread throughout the body and form dangerous secondary tumors. In pre-clinical models, scientists demonstrated that restoring miR-342 levels markedly reduced the spread of cancer cells to distant organs. Furthermore, researchers discovered that palbociclib, an existing CDK4/6 inhibitor drug currently approved for hormone receptor-positive breast cancers, significantly halted metastatic tumor growth in models exhibiting low miR-342 levels. The findings suggest measuring miR-342 levels could allow doctors to repurpose existing therapeutics to treat high-risk patients. Co-senior author Associate Professor Philip Gregory from Adelaide University’s Centre for Cancer Biology confirmed that preventing metastasis remains the primary challenge in treating aggressive breast cancers. Gregory emphasized that because palbociclib targets the overactive E