RARRES2 and neoplasm: Previous studies have confirmed that chemerin can increase the invasion of gastric cancer cells, and promote tumor invasion and metastasis by inducing the phosphorylation of p38, extracellular signal-regulated kinases 1 and 2 (ERK1/2) and mitogen-activated protein kinase (MAPK), up-regulating vascular endothelial growth factor (VEGF), matrix metalloproteinase-7 (MMP-7) and interleukin 6 (IL-6) 28, 29.