The GIP/GIPR axis is functionally linked to GH-secretion increase in a significant proportion of gsp− somatotropinomas

Abstract

We demonstrate that <i>GIPR</i> mediates the GH-PI in a significant proportion of <i>gsp</i>^- acromegalic patients. In these cases, the stimulatory effect of IGF-1 on GIP promoter support the hypothesis of a functional GH/IGF-1/GIP axis. Further studies based on larger cohorts and the development of a stable transgenic model with inducible GIPR overexpression targeted to pituitary somatotroph lineage will be mandatory to establish the real role of GIPR in the pathogenesis of somatotropinomas.