ADELAIDE, Australia / RankWire.AI / – 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. This subtype lacks estrogen, progesterone, and HER2 receptors, rendering conventional targeted hormone therapies ineffective. 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.
Diagnostic Biomarker Testing May Identify Patients Most Likely to Benefit
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 E2F pathway, administering the drug after cancer cells spread prevented microscopic deposits from expanding. Rather than focusing solely on shrinking primary tumors, this therapeutic approach stops microscopic secondary cancers from developing into life-threatening conditions.
Molecular Switch miR-342 Acts as Master Regulator for Cancer Genes
The scientific team noted that triple-negative breast cancer is biologically diverse, which has historically hindered the development of universal targeted treatments. By pinpointing a specific biological weakness shared by a distinct patient subgroup, the study opens the door to personalized treatment regimens. As Australian researchers uncover a promising new way to tackle triple-negative breast cancer, research teams are preparing to validate the findings using patient-derived models ahead of clinical trials.
Medical oncologists and cancer research organizations across Australia welcomed the findings, noting the urgent need for expanded treatment options when primary therapies fail. The research team plans to collaborate with international clinical networks to accelerate biomarker screening protocols. Validating miR-342 testing could soon allow clinicians to select suitable candidates for targeted CDK4/6 inhibitor therapies during early intervention phases.
