Both murine SCC VII and primary human tumor cells collected from patients with HNSCC responded similarly in vitro to Rho kinase inhibition, which promoted a CD44hi tCSC phenotype additionally associated with coexpression of other stem cell markers including ALDH1A1, EpCAM, and EGFR (Supplemental Figure 1, B–D) (10). Here, ALDH1A1 is linked to head and neck squamous cell carcinoma.