Myc is necessary for mammary tumor formation in K5ΔNβcat animals. A. Double immunofluorescence analysis of a K5ΔNβcat tumor with anti-HA (red), and anti-Myc (green) antibodies. Arrows indicate the presence of nuclei positively stained for Myc. Bar: 40 μm. B. qPCR analysis of Myc target genes. The graph shows mean ± SEM for four control tissue and five K5ΔNβcat tumor samples; p < 0.05. C. Kaplan-Meier tumor-free survival curve of K5ΔNβcat virgin and parous mice. 17 virgin and 10 parous K5ΔNβcat, 14 virgin and 6 parous K5ΔNβcat;K5Cre;MycF/+and 12 virgin and 10 parous K5ΔNβcat; K5Cre;MycF/Ffemales were analyzed.