IGFBP4 and adrenal gland pheochromocytoma: In MEN2/NF1-related PCC, downregulation of IGFBP3 and IGFBP7 was observed in two studies and the downregulation of IGFBP4 and IGFBP5 was correlated with the overexpression of hsa-miR-132 and has-miR-885-5p.