IGF1 and adenocarcinoma: Previous studies have suggested that IGFBP7 may sustainably activate the downstream PI3K/AKT signaling pathway by prolonging the action of IGF1 on the IGF1R.[37] However, other studies have used IGFBP7 at concentrations that are significantly higher than the physiological levels and observed that it inhibits IGF1R activation on adenocarcinoma cell surfaces, thereby suppressing the transmission of the downstream PI3K/AKT signaling pathway.