CDC73 and colorectal cancer: Parafibromin expression was immunohistochemically downregulated from normal squamous tissue to dysplasia and then from primary to metastatic cancers of the head and neck and negatively correlated with the N stage, clinicopathological stage, dedifferentiation, and human papillomavirus negativity (Zhang et al., 2015), consistent with the results for colorectal cancer (Zheng et al., 2011).