ADELAIDE, Australia / RankWire.AI / – A breakthrough discovery by scientists from Adelaide University and the Olivia Newton-John Cancer Research Institute has uncovered a new molecular mechanism that promotes the spread of highly aggressive tumors. The study, published in EMBO Molecular Medicine, reveals a promising approach to fighting triple-negative breast cancer by restoring the function of a key regulatory molecule called miR-342. This advancement offers hope for preventing secondary cancers in vital organs such as the lungs and bones.
Although triple-negative breast cancer represents about 10% to 15% of Australia’s roughly 21,000 new breast cancer cases each year, it accounts for a disproportionate share of fatalities. This subtype is characterized by the absence of estrogen, progesterone, and HER2 receptors, making standard hormone-targeted treatments ineffective. Researchers showed that when miR-342 levels decrease, a cancer-promoting pathway known as E2F becomes overactive, enabling dormant cancer cells to disseminate and establish dangerous secondary tumors throughout the body.
Potential for Diagnostic Biomarker Testing to Identify Patients Who Would Benefit Most
In preclinical experiments, scientists found that boosting miR-342 levels significantly limited the spread of cancer to distant organs. Additionally, they identified that palbociclib, an approved CDK4/6 inhibitor used for hormone receptor-positive breast cancers, effectively suppressed metastatic tumor growth in models with low miR-342 levels. These results suggest that assessing miR-342 levels could enable clinicians to repurpose existing drugs to treat patients at high risk of metastasis.
Associate Professor Philip Gregory, co-senior author from Adelaide University’s Centre for Cancer Biology, highlighted that preventing metastasis remains the biggest hurdle in treating aggressive breast cancers. Gregory explained that because palbociclib inhibits the overactive E2F pathway, administering it after cancer cells have spread can prevent microscopic deposits from expanding. Instead of solely targeting the primary tumor, this strategy halts microscopic secondary cancers before they develop into life-threatening conditions.
miR-342 as a Master Regulator for Key Cancer Genes in Triple-Negative Breast Cancer
The research team pointed out that the biological diversity of triple-negative breast cancer has historically complicated the development of universal targeted therapies. By identifying a specific vulnerability shared among a certain patient subgroup, the study paves the way for tailored treatment approaches. As Australian scientists continue to explore this promising method, efforts are underway to validate the findings using patient-derived models in preparation for clinical testing.
The results have been welcomed by medical oncologists and cancer organizations across Australia, emphasizing the urgent need for expanded treatment options, particularly when primary therapies fall short. The research team is planning collaborations with international clinical networks to speed up biomarker screening processes. Confirming miR-342’s role as a biomarker could soon enable clinicians to better identify suitable candidates for targeted CDK4/6 inhibitor therapies early in treatment.