ADELAIDE, Australia / RankWire.AI / – Research teams from Adelaide University and the Olivia Newton-John Cancer Research Institute have pinpointed a new molecular mechanism responsible for the progression of aggressive tumors. Their findings, published in EMBO Molecular Medicine, reveal a promising approach to address triple-negative breast cancer by reactivating a vital regulatory molecule called miR-342. This breakthrough paves the way for strategies aimed at preventing the development of secondary cancers in organs such as the lungs and bones.
Although triple-negative breast cancer constitutes 10% to 15% of the approximately 21,000 breast cancer cases diagnosed annually in Australia, it accounts for a larger share of mortality. This form of cancer is characterized by the absence of estrogen, progesterone, and HER2 receptors, which renders standard hormone-targeted therapies ineffective. The research demonstrated that a decline in miR-342 levels activates the E2F pathway, a driver of tumor growth, enabling dormant cancer cells to spread and form dangerous secondary growths throughout the body.
Potential of Diagnostic Testing to Identify Patients Who May Benefit Most
Using pre-clinical models, scientists showed that restoring miR-342 significantly decreased cancer cell dissemination to distant tissues. Additionally, they found that palbociclib, a CDK4/6 inhibitor already approved for hormone receptor-positive breast cancers, effectively slowed the growth of metastatic tumors in models with low miR-342 levels. These results imply that assessing miR-342 levels could enable clinicians to repurpose existing drugs for high-risk patient groups.
Associate Professor Philip Gregory from Adelaide University’s Centre for Cancer Biology, co-lead author, confirmed that preventing metastasis remains the main challenge in managing aggressive breast cancers. Gregory highlighted that since palbociclib inhibits the overactive E2F pathway, its use after cancer has already spread can prevent microscopic deposits from enlarging. Instead of merely reducing primary tumor size, this method aims to halt the development of secondary cancers at a microscopic stage before they become life-threatening.
miR-342 as a Central Regulator of Cancer-Related Genes
The researchers emphasized that triple-negative breast cancer presents significant biological heterogeneity, which has historically impeded the development of universal targeted therapies. By identifying a specific biological vulnerability shared among a subgroup of patients, the study provides a pathway toward more personalized treatments. As Australian scientists explore a novel method to combat triple-negative breast cancer, efforts are underway to validate these findings using patient-derived models prior to clinical testing.
The research received strong support from medical oncologists and cancer organizations across Australia. They acknowledged the critical need for expanding treatment options, especially when primary therapies fall short. Plans are in motion for the research team to collaborate with international clinical networks to speed up biomarker screening processes. Validating miR-342 testing could enable early identification of candidates suitable for targeted CDK4/6 inhibitor treatments, potentially improving patient outcomes during initial therapy stages.