The Role of Receptor–Ligand Interaction in Somatostatin Signaling Pathways: Implications for Neuroendocrine Tumors

Abstract

Neuroendocrine tumors (NETs) arise from neuroendocrine cells and manifest in diverse organs. Key players in their regulation are somatostatin and its receptors (SSTR1–SSTR5). Understanding receptor–ligand interactions and signaling pathways is vital for elucidating their role in tumor development and therapeutic potential. This review highlights SSTR characteristics, localization, and expression in tissues, impacting physiological functions. Mechanisms of somatostatin and synthetic analogue binding to SSTRs, their selectivity, and their affinity were analyzed. Upon activation, somatostatin initiates intricate intracellular signaling, involving cAMP, PLC, and MAP kinases and influencing growth, differentiation, survival, and hormone secretion in NETs. This review explores SSTR expression in different tumor types, examining receptor activation effects on cancer cells. SSTRs’ significance as therapeutic targets is discussed. Additionally, somatostatin and analogues’ role in hormone secretion regulation, tumor growth, and survival is emphasized, presenting relevant therapeutic examples. In conclusion, this review advances the knowledge of receptor–ligand interactions and signaling pathways in somatostatin receptors, with potential for improved neuroendocrine tumor treatments.