NRG/ErbB signaling: on the trail of a molecular fingerprint in mucinous carcinoma

Introduction: Human neuregulins (NRG) are small epidermal growth factor ligands, involved inthe activation of ErbBs receptors. Among genomic aberrations, the NRG fusionsare one of the most intriguing genetic markers reported in the latest years,due to their agnostic and potentially predictive features. Mucinous carcinomashowed a higher rate of mutations in downstream effectors of NRG/ErbBactivation, thus suggesting that RAS/MAPK and PIK3K/AKT pathway are involved inmucinous phenotype development and aggressiveness. Areacovered: Epidemiological data on the spectrum ofall NRG/ErbBs and downstream effectors alterations in mucinous carcinoma of digestivetract, ovary, lung, and pancreato-biliary tract, as well as their correlationwith respective immunological and molecular background are discussed. Peer-reviewedpublications on high-quality international from PubMed and data from scientificofficial sites were used to update the current literature. Expertopinion: Recent scientific advances highlightthe predictive and prognostic role of the NRGs/ErbBs network deregulation incancer; anyhow its role is not well investigated in solid tumors with mucinousfeatures. Although the mucin-rich cancers have a considerably greater rate ofmutations in therapeutically critical pathways than non-mucinous ones, commonmucinous pathways have not yet been found.