ADELAIDE, Australia / RankWire.AI / – Researchers in Australia have discovered a molecular switch that controls the spread of aggressive tumors. This finding offers a new potential pathway for therapy to prevent secondary cancers. Their study, published in EMBO Molecular Medicine, involves scientists from Adelaide University and the Olivia Newton-John Cancer Research Institute. They showed that restoring a key regulatory molecule called miR-342 can greatly reduce tumor metastasis. These results suggest a promising new strategy to combat triple-negative breast cancer by targeting dormant cancer cells before they form deadly secondary tumors in distant organs.

Triple-negative breast cancer makes up 10% to 15% of Australia’s roughly 21,000 annual breast cancer cases. It causes a higher number of deaths relative to its incidence. This subtype lacks estrogen, progesterone, and HER2 receptors, so standard hormone therapies do not work. The investigators found that when miR-342 levels decrease, a cancer-promoting pathway called E2F becomes overactive. This allows dormant cancer cells to spread and develop into dangerous secondary tumors.
Targeted Treatments Bring New Hope for Preventing High-Risk Metastasis
In laboratory models, scientists showed that raising miR-342 levels greatly reduced the spread of cancer to other organs. They also found that palbociclib, a CDK4/6 inhibitor approved for hormone receptor-positive breast cancers, significantly slowed metastatic tumor growth in models with low miR-342 levels. These results suggest that testing miR-342 could help doctors repurpose existing drugs to treat patients at high risk of metastasis.
Associate Professor Philip Gregory from Adelaide University’s Centre for Cancer Biology, a co-senior author, said that preventing metastasis remains the biggest challenge in treating aggressive breast cancers. Gregory highlighted that because palbociclib targets the overactive E2F pathway, giving the drug after cancer spreads can stop microscopic deposits from growing. Instead of only shrinking primary tumors, this approach aims to prevent microscopic secondary cancers from becoming life-threatening.
Pre-Clinical Results Published in Peer-Reviewed EMBO Molecular Medicine
The research team pointed out that triple-negative breast cancer is biologically diverse. This diversity has made it difficult to develop universal targeted treatments. By identifying a specific weakness shared by a subgroup of patients, the study paves the way for personalized therapies. As Australian scientists look for new ways to fight triple-negative breast cancer, efforts are underway to validate these findings using patient-derived models before moving to clinical trials.
Medical oncologists and cancer research groups across Australia welcomed these results. They emphasized the urgent need for more treatment options when primary therapies do not succeed. The team plans to work with international clinical networks to speed up biomarker screening. Validating miR-342 testing could soon help clinicians identify suitable candidates for targeted CDK4/6 inhibitor treatments early on, improving intervention outcomes.
