According to this publicly available database, among the 10 FZD genes, the differential expression of FZD2 in head and neck squamous cell carcinoma (501 cases of cancer and 41 cases of normal) and tongue cancer (149 cases of cancer and 15 cases of normal) was the most obvious compared with normal tissues (Fig 1A). Here, FZD2 is linked to head and neck squamous cell carcinoma.