IGFBP3 and esophageal squamous cell carcinoma: Zhao et al. (2012) found that serum expression level of IGFBP3 correlated significantly with clinical pathological stage of ESCC. The serum level of IGFBP3 was also significantly correlated with lymph node metastasis as well as tumor stage in another study (Hou et al., 2019). In addition, in CRC tissue, Keku et al. (2008) found that IGFBP3 mRNA levels were positively correlated with apoptosis. Yan et al. (2017) recently reported the significant correlation between IGFBP3 expression and tumor size, node metastasis, and clinical stage in HCC.