Glioblastoma and Extrachromosomal DNA: A Tale of Divergent Inheritance

We often think of our DNA as a nice tightly wound package that exists within the nucleus of the cell. Yet, in various cancers, there are fragments of our genetic code that reside outside of the contiguous genome—called extrachromosomal DNA (ecDNA)—that play a critical role in carcinogenesis and chemotherapy resistance. For instance, glioblastoma (GBM), the most common and aggressive form of brain cancer, has an extremely poor response to standard-of-care treatment, with a two-year su