Abstract Extrachromosomal DNA (ecDNA) amplifies oncogenes with high copy-number variability, promoting heterogeneity, rapid tumor evolution and treatment failure. MDM2, a key negative regulator of TP53, is frequently amplified on ecDNA, yet its impact on ecDNA dynamics and ecDNA dosage-driven treatment responses remains unclear. We integrated pan-cancer ecDNA reconstructions (TCGA + PCAWG), single-cell DNA FISH and ImmunoFISH, scRNA-seq, scG Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7511.
Schmargon et al. (Fri,) studied this question.