My research explores the unknown biology of the extracellular basement membrane protein complex FRAS1/FREM2 and its role in breast and prostate cancer progression to metastasis. I focus on understanding how imbalances in FRAS1 and FREM2 expression influence tumour cell behaviour, metastatic competence, and therapeutic response. Using genomic editing approaches, 3D culture systems, and complementary in vitro and in vivo models, I characterise how altered FRAS1/FREM2 expression regulates epithelial mesenchymal transition and NF-κB signalling pathways, both of which are strongly implicated in metastatic progression. I also examine how these proteins are dynamically modulated in response to clinically relevant therapies. By identifying shared and distinct regulatory mechanisms across hormone-driven cancers, this research enhances the translational relevance of findings in both breast and prostate cancer and broadens their potential clinical applicability.