IGFBP7 and cholangiocarcinoma: As a unique member of IGFBPs, studies have shown that IGFBP7 plays important roles in regulating cell proliferation, adhesion and differentiation in many cell lines.9, 10 IGFBP7 has also been implicated as a tumour suppressor in a variety of human malignancies including thyroid carcinoma,11 cholangiocarcinoma,12 gastric cancer,13 hepatocellular carcinoma14 and breast cancer.15 Notably, there is increasing evidence, suggesting that IGFBP7 is involved in bone metabolism.