Figure 1. Oncogene amplification on ecDNA is a frequent event in cancer and promotes tumour heterogeneity.
a | The frequency of extrachromosomal DNA (ecDNA) amplification across newly diagnosed cancer7–10. b | EcDNA elements are replicated in S-phase and due to the absence of centromeres, segregate unevenly to daughter cells during mitosis. Clonal selection of tumour cells with an ecDNA-endowed proliferative advantage enables rapid intercellular diversification of ecDNA copy number and increases intratumoral heterogeneity.