Figure 2.

Evaluating Shh and Nrf2 protein expression in tumor tissues by immunostaining. (a, b) We classified the HNSCC tumors as Shh^high/Shh^low and Nrf2^high/Nrf2^low. Shh^high and Nrf2^high samples were scored as Score2 and Score3 if the staining intensity of Shh and Nrf2 showed dense nuclear expression in the entire section of tumors. Similarly, Shh^low and Nrf2^low were scored as Score0 and Score1, if the staining intensity was completely lacking or the minority of cells were positive for either Shh or Nrf2. The samples were subclassified as Score0 if Shh expression was completely lacking (28.96%, 53 of 183); Score1 if staining was weak or sporadic (26.23%, 48 of 183); Score2 if staining intensity was moderate (14.75%, 27 of 183); and Score3 if staining intensity was strong (30.60%, 55 of 183). For Nrf2, samples were subclassified as Score0 if Nrf2 expression was completely lacking (20.77%, 38 of 183); Score1 if staining intensity was weak and sporadic (21.30%, 39 of 183); Score2 if the staining intensity was moderate (19.20%, 37 of 183); and Score3 if staining was strong and widespread (38.79%, 71 of 183). For staining intensity comparison one-way ANOVA was used, p < 0.0001).

ANOVA, analysis of variance; HNSCC, head and neck squamous cell carcinoma.