Epithelial-to-mesenchymal transition as a central driver of tumor cell plasticity

Epithelial-to-mesenchymal transition (EMT) is a central driver of cancer cell plasticity, enabling invasion, immune evasion, therapeutic resistance and metastasis. Rather than a binary switch, EMT comprises a continuum of transient, reversible states that endow tumor cells with distinct functional properties. Recent technological advances have revealed an unexpected diversity of EMT states across tumor contexts, with implications for disease progression and therapy response. In this Review, we synthesize emerging evidence on EMT heterogeneity and dynamics during cancer progression, examine how new methodologies have increased our understanding of the process and outline therapeutic challenges and opportunities.