Shinno et al. and AndKajiwara et al. analyzed 119 cases and 72 cases of esophageal squamous cell carcinoma (ESCC) and showed that expression of CKAP4, along with DKK1 and/or DKK3, in ESCC was associated with poor prognosis (Kajiwara et al., 2018; Shinno et al., 2018) (Table 2). Here, CKAP4 is linked to esophageal squamous cell carcinoma.