RAF/MAP kinase cascade Gastrin binds to CCK-B receptor PathwayStep5823 PathwayStep5829 PathwayStep5764 Gastrin-CREB signalling pathway via PKC and MAPK Authored: Jassal, B, Tripathi, S, 2012-04-04 Edited: Jassal, B, Tripathi, S, 2012-04-04 Gastrin is a hormone whose main function is to stimulate secretion of hydrochloric acid by the gastric mucosa, which results in gastrin formation inhibition. This hormone also acts as a mitogenic factor for gastrointestinal epithelial cells. Gastrin has two biologically active peptide forms, G34 and G17.Gastrin gene expression is upregulated in both a number of pre-malignant conditions and in established cancer through a variety of mechanisms. Depending on the tissue where it is expressed and the level of expression, differential processing of the polypeptide product leads to the production of different biologically active peptides. In turn, acting through the classical gastrin cholecystokinin B receptor CCK-BR, its isoforms and alternative receptors, these peptides trigger signalling pathways which influence the expression of downstream genes that affect cell survival, angiogenesis and invasion (Wank 1995, de Weerth et al. 1999, Grabowska & Watson 2007) Pubmed10413847 Pubmed17698287 Pubmed7491953 Reactome Database ID Release 43881907 Reactome, http://www.reactome.org ReactomeREACT_120966 Reviewed: D'Eustachio, P, 2012-04-23 EGFR Transactivation by Gastrin G alpha (q) signalling events RSK1/2/3 phosphorylates CREB at Serine 133 PathwayStep3475 PathwayStep3467 ERK1/2/5 activate RSK1/2/3 PathwayStep3857