Targeting ecDNA

Extrachromosomal DNA (ecDNA) has emerged as a crucial player in cancer biology, particularly in driving oncogene amplification, promoting intratumoral heterogeneity, and conferring resistance to conventional therapies. Unlike chromosomal DNA, ecDNA exists outside the linear genome and replicates independently, enabling rapid evolution of cancer cells and enhanced expression of oncogenes without the constraints of chromatin regulation. Recent advances in sequencing and imaging technologies have deepened our understanding of ecDNA’s structural complexity, biogenesis, and functional roles in tumor progression. These insights have highlighted ecDNA as a promising therapeutic target. Novel strategies aiming to target ecDNA include disrupting its formation, inhibiting its replication, promoting its degradation, or re-sensitizing ecDNA-harboring cells to existing therapies. CRISPR-Cas systems, DNA-damaging agents, and inhibitors of DNA repair pathways have shown potential in selectively impairing ecDNA-driven oncogenic processes. Additionally, targeting the unique vulnerabilities of ecDNA-positive tumors, such as their dependence on specific transcriptional programs and stress response pathways, offers new avenues for precision medicine. This review explores the biology of ecDNA, its implications in cancer, and current progress in therapeutic strategies targeting ecDNA. Harnessing these novel approaches may pave the way for more effective and durable cancer treatments, especially in refractory and aggressive tumor types.