SPINK5 and esophageal cancer: To further investigate the relationship between the expression level of SPINK5 protein and the clinicopathological features of esophageal cancer, we examined the expression level of SPINK5 protein in 205 cases of esophageal cancer by immunohistochemistry, the results showed that the expression level of SPINK5 protein was closely related to lymph node metastasis and pathological differentiation of esophageal cancer (Figure 1B,C, Table 1).