Compared to the parental and shNeg controls, SMURF1 knockdown significantly reduced the number of CD44high cells in SCC-58 SDCs (p = 0.0092 compared to shNeg, p = 0.037 compared to parental; n = 7) as shown in Figure 6D. We also noted that the CD44high population in the TR146 SDCs was less than the CD44high population in the SCC-58 SDCs, demonstrating the potential heterogeneity that may exist within HNSCC. The gene discussed is SMURF1; the disease is head and neck squamous cell carcinoma.