KRT19 and head and neck squamous cell carcinoma: Although K19-Wnt1/C2mE-KP cells manifested the resistance to sulfasalazine treatment, the exposure to the combination of dyclonine and sulfasalazine greatly reduced the survival of these cells in vitro (Figure 5C), suggesting that combination therapy with these agents might be effective for the treatment of tumors formed by CD44v-expressing stemlike cancer cells not only in HNSCC but also in gastric cancer.