Figure 4.

Double minute chromosome-amplified oncogenes are lost as micronuclei or transformed into homogeneously staining regions during the S/G₂ phases of the cell cycle. (A) Representative micrographs indicating the two groups of miconuclei in UACC-1598 cells: those with fluorescence signals (MN⁺) and those without (MN⁻). (B) Homogeneously staining regions (HSRs) are present in metaphase UACC-1598 cells with U0126 and PD98059 treatment. (C, D) The percentage of HSRs with U0126 and PD98059 treatment. (E) The cell cycle distribution of ERK1/2 inhibitor-treated UACC-1598 cells; ^*p < 0.025, ^**p < 0.005; χ² test compared to DMSO