CD44 and Bloom syndrome: Significant elevation in the mRNA levels of activated fibroblast markers, such as collagen type 1, fibronectin, and α-SMA, and invasive fibroblast phenotype-regulating molecules, such as CD44, MMP9, MMP12, and MMP14, were also observed in primary fibroblasts from Gas6−/− mice at 14 days post-BLM treatment than in those from WT control mice (Fig. 7d).