CCL2 and pancreatic neoplasm: It has been reported that senescent cells can produce a variety of cytokines (SASP), including IL-6, IL-8, tumor necrosis factor α (TNF-α), monocyte chemoattractant protein 1 (MCP-1), etc. (Coppe et al., 2010; Acosta et al., 2013), which promotes the occurrence and development of tumor; paracrine IL-6 can induce the proliferation of human lung fibroblasts and the growth and metastasis of pancreatic cancer cells (Huang et al., 2016; Klee et al., 2016).