Loss of 1 Allele of Egr1, Tp53, or both genes equally accelerates Apc^del/+-induced fatal anemia. Kaplan-Meier survival curve of Apc^fl/+ control mice and Apc^del/+mice, crossed with Egr1^+/− (A), Tp53^+/− (B), or Egr1^+/− and Tp53^+/− (C). Percent survival (time to sacrifice of moribund animals) is plotted vs time in days, post-pIpC treatment (to induce Apc deletion). The number of mice in each cohort is shown. Egr1^+/−, Apc^del/+; Tp53^+/−, Apc^del/+; and Egr1^+/−, Tp53^+/−, Apc^del/+ mice all had significantly decreased survival compared with Apc^del/+ mice (P < .0001). The deletion of a single allele of Apc was induced in Mx1-Cre⁺Apc^fl/+ mice treated with 3 doses of pI-pC, referred to as Apc^del/+mice. Control Mx1-Cre⁻Apc^fl/+ mice are referred as Apc^fl/+mice.