Chronic Rsf-1 induction leads to chromosomal abnormality. A, the frequency of abnormal mitoses including micronuclei, abnormal spindle pole number, and anaphase bridge increases in the Rsf-1-induced RK3E cells (filled symbols) as compared with noninduced controls (open symbols) at different time points. B, karyotypic analysis demonstrates different types of gross karyotypic abnormality in Rsf-1 induced cells. C, examples of karyotypes in Rsf-1-induced (Rsf-1 on) and noninduced (Rsf-1 off) cells. D, array CGH showed clonal DNA copy number alterations including deletion in ch5, ch7, and ch9, and amplification in ch7 in RK3E cells after Rsf-1 induction, whereas Rsf-1-noninduced and mock-induced RK3E (vector-only control) cells displayed no such changes. Error bar: one standard error.