FIG. 6.
Rapamycin increases the frequency of chromosome and chromatid breaks. Panels A–C: Frequencies of chromosome and chromatid breaks. Thirty to 50 metaphases for each sample were analyzed. The data shown are from one of two independent experiments. Representative metaphase spreads in irradiated MCF7 cells pretreated with rapamycin are shown. FISH using telomeric probe reveals the red/pink color. Chromatid-type and chromosome-type breaks are indicated by arrowheads. Panel D: A typical radial structure induced by radiation from cells pretreated with rapamycin. Star-shaped quadri-radial chromosomes are indicated by arrowheads. IR, ionizing radiation; Rap, rapamycin; met, metaphase.
