Have you ever heard someone say “I thought my cancer was in remission, but now it has come back”? It’s one of the saddest things you’ll hear. Or heard how suddenly someone’s cancer has suddenly become resistant? And why do tumours spread so quickly, and so suddenly, sometimes-and other times not? The answer may be Extrachromosomal DNA or ecDNA as it’s called in the business.
According to Robin McKie of the Guardian  ecDNA can be thought of as free floating lumps of DNA which can dodge in and out of the main chromosomes almost at whim. And they can carry oncogenes, which seem to be the key factors in cancer genesis. And get this from Robin’s key paragraph:
“………We have now discovered that, in some of the most aggressive forms of cancer, the oncogenes aren’t where we thought they were. They are actually on extrachromosomal DNA,” said Mischel.“The vulnerable gene had quickly disappeared when threatened by cancer drugs and was hidden in ecDNA. Then it reappeared once it was safe for it to start causing damage again.”
Who Mischel is, and why he said it is down to you to discover, gentle reader, by reading the article. You should: Robin’s an excellent science writer.
Our thoughts? Well for what it may be worth, these ecDNA johnnies sound little bit like viruses, the way they can jump in and out of genomes and all that.(spoiler alert: we are not microbiologists) And what has all this to do with satellite regions, non coding areas, epigenetics and multiple gene copies, and that whole mish mash of stuff where microbiology meets information theory? But these researchers are definitely on to something. We hope.
#cancer #tumour #ecDNA #oncology