IL6 and neoplasm: In particular, mast cells play a role in tumor initiation, maintenance, and growth by synthesizing and secreting matrix metalloproteinases, various cytokines (IL6 and TNFα), and multiple mitogens [vascular endothelial growth factor precursor (VEGF) and platelet-derived growth factor (PDGF)] (Galli and Tsai, 2008; Galli et al., 2008).