Figure 1
From: Recent advances reveal IL-8 signaling as a potential key to targeting breast cancer stem cells
Model of cytokine networks depicting the proposed interactions between breast cancer cells and stromal cells. (a) Interleukin-8 (IL-8) is secreted by cancer cells, mesenchymal cells, and macrophages via multiple signaling pathways. (b) IL-8 promotes breast cancer stem-like cell (CSC) activity via CXCR1/2 by activating EGFR/HER2-dependent and -independent signaling pathways. Red circles denote CXCR1/2 ligands: IL-8/CXCL8, CXCL1/GRO-α, CXCL5, CXCL6/GCP-2, and CXCL7/NAP-2. bFGF, basic fibroblast growth factor; CXCL, C-X-C motif ligand; EGFR, epidermal growth factor receptor; FGFR, fibroblast growth factor receptor; GCP-2, granulocyte chemotactic protein-2; GRO, growth-regulated oncogene; HER2, human growth factor receptor 2; IGF-1R, insulin-like growth factor 1 receptor; JAK/STAT, Janus kinase/signal transducers and activators of transcription; NAP-2, neutrophil-activating protein-2; Src, sarcoma kinase; TGF-β, transforming growth factor-beta.