CXCL8 and neoplasm: SASP refers to the ability of senescent cells to overproduce multiple cytokines (e.g., IL-1, IL-6), chemokines (e.g., IL-8, MCP-1, GRO-1, SDF-1), growth factors (e.g., TGF-β, VEGF, heregulin), and extracellular matrix (ECM) resysteming agents (e.g., PAI-1, -2, tPA, uPA) that promote various steps in tumor progression, including adhesion, proliferation, migration, invasion, epithelial–mesenchymal transition (EMT), and angiogenesis [176].