Murine cohorts were generated harboring Pax8-Cre driven inactivation of different
combinations of the Brca (Brca1 or Brca2), Tp53 (loss of function and/or dominant negative
inactivating R270H mutation), and Pten genes, which are commonly altered in ovarian
cancer patients (Figure 2A–D) (TCGA, 2011). Heterozygous and homozygous Brca1 (and
Brca2) mutants (mut), unless otherwise indicated, will collectively be designated Brca1mut
(Brca2mut) as they yielded similar tumor phenotypes. Similarly, Tp53−/− gave similar results
as Tp53R270H/− and therefore are collectively designated Tp53mut. The Kaplan-Meier curves
of the 5 Pax8-rtTA;TetO-Cre murine cohorts, Brca1−/−;Tp53mut;Pten−/−,
Brca1+/−;Tp53mut;Pten−/−, Brca2−/−;Tp53mut;Pten−/−, Brca2+/−;Tp53mut;Pten−/−, and
Tp53−/−;Pten−/− mice are shown for comparison in Figure 2C. Interestingly, we noticed a
statistically significant increase in disease latency in the Tp53−/−; Pten−/− cohort in
comparison to either Brca1mut;Tp53mut;Pten−/− or Brca2mut;Tp53mut;Pten−/− mice (p <
0.01, Figure 2C). Furthermore, the survival of Brca2−/− mice was significantly lower when
compared to Brca2+/− mice (p < 0.05, Figure 2C). Otherwise, the heterozygous and
homozygous Brca1 and Brca2 animals yielded similar phenotypic results. Evidence of
Brca2, Tp53, and Pten recombination in our animal models is shown in Figure 2D while the
efficiency of recombination events at the 3 genetic loci is displayed in Figure 2E.