So, the results of Bmi-1 expression correlated with lymph node metastasis or clinical stage in in vivo study was accordance with the results in in vitro study, while the results of no correlation was found between Mel-18 expression and clinicopathological factors in in vivo study was not accordance with the results in in vitro study, we suspected that one of the reason may due to the reliability of IHC method which was used to detect the expression of Bmi-1 and Mel-18 in tumor tissues in most paper of literature including our previous study. The gene discussed is PCGF2; the disease is metastatic malignant neoplasm in the lymph nodes.