Paracrine signaling via secreted cytokines, growth factors, and extracellular vesicles

Paracrine signaling via secreted cytokines, growth factors, and extracellular vesicles refers to a **cellular communication mechanism** where cells secrete soluble proteins or vesicles that act locally on neighboring cells. These mediators include **cytokines**—small proteins involved in immune responses; **growth factors**—proteins that regulate cell proliferation and differentiation; and **extracellular vesicles**—membrane-bound particles carrying proteins, lipids, RNA, or surface ligands. The signals typically diffuse over short distances within tissues to alter the behavior of nearby cells. This form of local intercellular communication is distinct from endocrine signaling (long-range) and autocrine signaling (self-targeting). Paracrine signals play critical roles in development, tissue repair/regeneration, immune modulation, angiogenesis, tumor progression/metastasis formation through modification of the microenvironment—including promoting cancer cell motility/invasion by EVs—and regulation of inflammation. Many well-known families are involved in paracrine processes such as fibroblast growth factor family (FGF), transforming growth factor-beta superfamily (TGF-beta), Wnt family members for morphogenesis/developmental patterning; interleukins for immunity; vascular endothelial growth factor for angiogenesis. Therapeutically relevant targets within these pathways are usually individual receptors or ligands rather than "paracrine signaling" itself—for example inhibitors against VEGF-A/VEGFR2 axis in cancer therapy. Thus "paracrine signaling via secreted cytokines/growth factors/extracellular vesicles" is not itself a druggable molecular entity but an umbrella term describing multiple possible targets/processes. Because this entry describes a *process* rather than any single protein/receptor/enzyme/transporter/etc., it should be flagged as incorrect if used where only discrete molecular targets are appropriate.[1][3][4][5]

Other names

Paracrine signalingParacrine communication via cytokines/growth factors/EVsLocal cell-to-cell signaling by secreted mediators