CDKN1B and esophageal squamous cell carcinoma: In ESCC group, a low expression of p27 protein was linked with pathology grading (OR: 2.16, 95% CI: 1.15–4.05, P = 0.017) but not with lymph node metastasis (OR: 1.97, 95% CI: 0.83–4.69, P = 0.124).