SLURP1 and head and neck squamous cell carcinoma: These results, taken together with the previous reports that (i) SLURP1 expression is downregulated in many metastatic tumors47, and (ii) the nuclear β-catenin levels are elevated in head and neck squamous cell carcinoma, basal cell carcinoma, prostate cancer, colorectal cancer and medulloblastoma48,49, suggest that SLURP1 serves as an anti-tumor agent by stabilizing β-catenin at cell membranes.