An Australian research team describes how neochromosomes — unusually large and sometimes circular chromosomes found in some cancers — arise. As they report in Cancer Cell, they performed a molecular analysis of such neochromosomes that are found in liposarcomas.
They arise, the team led by the Walter & Eliza Hall Institute of Medical Research's Anthony Papenfuss and David Thomas at Peter MacCallum Cancer Centre reports, through the chromothripsis or shattering of chromosome 12 to form a circular chromosome. Breakage-fusion-bridge events then amplify and shuffle certain loci around, while other loci are lost. And then the growing neochromosome begins to acquire new material.
It is more likely, the team says, to acquire genes linked to cancer that help it survive. "There's selection going on," Thomas tells the New Scientist.
It also either captures a foreign centromere or develops a neo-centromere and can then become linear, and more stable.
"Since the particular genes that were massively amplified in the neochromosomes were shown to be essential for their survival, drugs that turn those off are an obvious target for research," New Scientist says. Thomas adds that there are already trials of such drugs going on.