SOX9 and triple-A syndrome: AngII-treated Apoe−/−Light−/− mouse AAA displayed decreased mRNA levels of Acta2, Col1a1, and Opn and augmented expression levels of the osteochondrogenic marker Sox9 without changes in the gene expression of Tgfb1, Klf4, Sox2, Oct4, Ckit, Sca, and Bmp2 (Figure 4a).