ADELAIDE, Australia / RankWire.AI / – Scientists from Adelaide University and the Olivia Newton-John Cancer Research Institute have pinpointed a novel molecular switch that fuels the progression of aggressive tumors. The breakthrough, detailed in EMBO Molecular Medicine, suggests an innovative approach to managing triple-negative breast cancer by reestablishing the function of a key regulatory molecule called miR-342. This discovery paves the way for new strategies to prevent deadly secondary cancers in organs such as the lungs and bones.
Triple-negative breast cancer makes up 10% to 15% of Australia’s roughly 21,000 annual breast cancer diagnoses. Despite its relatively small proportion, it is responsible for a significant share of related fatalities. This type of cancer does not express estrogen, progesterone, or HER2 receptors, which makes standard hormone-targeted treatments ineffective. The research team found that when miR-342 levels decline, a cancer-promoting pathway called E2F becomes hyperactive. This overactivity enables dormant cancer cells to disseminate and develop into dangerous secondary tumors.
Potential for Diagnostic Biomarker Tests to Identify Patients Who Could Benefit Most
In laboratory models, scientists demonstrated that increasing miR-342 levels significantly curbed the spread of cancer to distant organs. They also identified that palbociclib, an already approved CDK4/6 inhibitor used in hormone receptor-positive breast cancers, effectively slowed down the growth of metastatic tumors in models with low miR-342 expression. These results suggest that assessing miR-342 could enable clinicians to repurpose existing treatments for patients at high risk of metastasis.
Associate Professor Philip Gregory, co-senior author from the Centre for Cancer Biology at Adelaide University, stressed that stopping metastasis is the key challenge in managing aggressive breast cancers. Gregory explained that because palbociclib inhibits the hyperactive E2F pathway, giving the drug after cancer has spread can prevent microscopic deposits from growing. Instead of only focusing on reducing the size of primary tumors, this approach aims to block the development of secondary cancers that could become life-threatening.
miR-342 as a Central Molecular Regulator for Cancer-Related Genes
The research team pointed out that triple-negative breast cancer exhibits significant biological diversity, which has historically complicated the creation of universal targeted therapies. By identifying a specific biological vulnerability common among a subset of patients, the study opens the door to personalized treatment options. As Australian scientists develop a promising new method to address triple-negative breast cancer, they are preparing to validate their findings using patient-derived models ahead of clinical trials.
Medical oncologists and cancer research organizations across Australia expressed enthusiasm about the study, emphasizing the critical need for expanded therapeutic options when initial treatments prove ineffective. The team plans to collaborate with international clinical networks to speed up biomarker screening protocols. Confirming miR-342 as a useful biomarker could soon enable clinicians to identify suitable candidates for targeted CDK4/6 inhibitor therapies during early intervention stages.