Paracrine signaling pathways in recipient tissues

Paracrine signaling pathways represent a fundamental mechanism of local cell-to-cell communication where signaling molecules secreted by a source cell act on nearby recipient cells to elicit a biological response (NIH, 2023). Unlike endocrine signaling, which involves systemic transport via the bloodstream, paracrine factors act over short distances within the local tissue microenvironment to maintain homeostasis or drive developmental processes (StatPearls, 2023). These pathways encompass a diverse array of molecular components, including growth factors, cytokines, and morphogens, which bind to specific receptors on recipient tissues to regulate cell proliferation, differentiation, and survival (Nature Reviews Molecular Cell Biology, 2020). In disease states such as cancer, aberrant paracrine signaling between malignant cells and the surrounding stroma is a key driver of tumor progression, angiogenesis, and immune evasion (Nature Reviews Cancer, 2017). While many therapeutic agents, such as Bevacizumab or Vismodegib, target specific components of these pathways, the term itself describes a broad physiological process rather than a single druggable molecule (PubMed, 2021). Consequently, targeting these pathways requires high specificity to avoid disrupting essential local signaling in healthy tissues. Therapeutic strategies often focus on neutralizing secreted ligands or blocking their cognate receptors on recipient cells to interrupt pathological communication loops. Understanding the spatial and temporal dynamics of these pathways is crucial for developing effective localized treatments.

Other names

Local signalingParacrine communicationNeighbor-to-neighbor signalingShort-range signaling

Modulation of local ligand-receptor interactions and downstream intracellular signaling cascades within the tissue microenvironment to interrupt pathological cell-to-cell communication.