Correlation analysis of MUC expression and clinicopathological parameters of patients with CRC found that MUC2 and MUC5AC were correlated with tumor stage, lymph node metastasis and prognosis of patients, and could be used as biomarkers to evaluate the prognosis of patients (Li et al., 2018), while the overexpression of MUC5B in CRC cells seemed to be related to degree of malignancy (Walsh et al., 2013), and increased expression of MUC6 was associated with malignancy and poor prognosis in CRC cells (Betge et al., 2016). The gene discussed is MUC5AC; the disease is colorectal carcinoma.