IGFBP5 and lung cancer: In humans, overexpression of IGFBP5 inhibited in vitro cell proliferation or angiogenesis in different tumor types (Hung et al. 2008; Rho et al. 2008; Su et al. 2011), whereas low serum IGFBP5 levels correlated with poor prognosis of lung cancer patients (Shersher et al. 2011).