ADELAIDE, Australia / RankWire.AI / – Researchers from Adelaide University and the Olivia Newton-John Cancer Research Institute have discovered a new molecular switch that influences the spread of aggressive tumors. Their findings were published in EMBO Molecular Medicine. The study reveals that restoring a key regulatory molecule called miR-342 could provide a novel approach to fighting triple-negative breast cancer. This discovery paves the way for new strategies to prevent deadly secondary cancers in organs such as the lungs and bones.
In Australia, triple-negative breast cancer makes up 10% to 15% of about 21,000 annual breast cancer cases. Despite its relatively small proportion, it accounts for a large share of fatalities. This subtype lacks estrogen, progesterone, and HER2 receptors, making targeted hormone treatments ineffective. The researchers showed that when miR-342 levels drop, a cancer-promoting pathway called E2F becomes overly active. This overactivity allows dormant cancer cells to travel and form dangerous secondary tumors throughout the body.
Testing for Diagnostic Biomarkers Could Help Identify Patients Who May Benefit Most
In pre-clinical experiments, scientists found that increasing miR-342 levels significantly decreased cancer spread to distant organs. They also tested palbociclib, an existing CDK4/6 inhibitor approved for hormone receptor-positive breast cancers. It notably slowed down metastatic tumor growth in models with low miR-342. These results suggest that measuring miR-342 could help doctors repurpose current drugs for high-risk patients.
Associate Professor Philip Gregory from Adelaide University’s Centre for Cancer Biology, co-senior author, stated that stopping metastasis remains the biggest challenge in treating aggressive breast cancers. Gregory explained that because palbociclib targets the overactive E2F pathway, giving the drug after cancer spread prevents tiny deposits from growing. Instead of only shrinking primary tumors, this method halts microscopic secondary cancers from becoming life-threatening.
MiR-342 Serves as a Master Regulator in Cancer Development
The research team highlighted that triple-negative breast cancer is biologically varied. This diversity has made it difficult to develop universal targeted treatments. By identifying a specific weakness shared among a patient subgroup, the study opens the possibility for personalized therapies. As Australian researchers find a promising new way to address this disease, efforts are underway to validate the findings with patient-derived models ahead of clinical trials.
Medical oncologists and cancer organizations across Australia welcomed the news. They stressed the importance of expanding treatment options when primary therapies fail. The research team plans to work with international clinical networks to speed up biomarker screening. Confirming miR-342 testing could soon help clinicians select patients for targeted CDK4/6 inhibitor therapies early on, improving treatment outcomes.