In this study, we also examined IGFBP-2 expression in 23 lung cancer tissue sections (Fig. 4), and found 69.6% (16/23) of the lung cancer specimens had low (43.5%) to high (26.1%) IGFBP-2 expression, and 82.6% (19/23) of the tissue specimens had anti-IGFBP-2 antibody levels above the cut-off value of 1,264.306 ng/ml (data were not shown). Here, IGFBP2 is linked to lung cancer.