IL6 and neoplasm: Experimental studies have shown that chemokines and cytokines, such as IL-8, IL-1β, IL-6, and TNF-α, produced by the cells present in the tumor microenvironment as well as by the tumor on its own, can positively influence neutrophil recruitment (Waugh and Wilson, 2008; Lechner et al., 2010) and thereby promote angiogenesis, tumor progression, and metastasis (Bekes et al., 2011).