Although the extent of replication fork collapse induced by 100 mM HU was reduced in parental H1299 cells compared to the other three cancer cell models, as indicated by a fainter 30–100 kb fragment fraction, quantification of these fragments in the parental H1299 and HMGA2 KO cells revealed consistent protection in the presence of HMGA2 (Fig 1C). Here, HMGA2 is linked to cancer.