Inflammatory cytokines in cancer: tumour necrosis factor and interleukin 6 take the stage

Up to 20% of all cancers arise in association with chronic inflammation and most, if not all, solid tumours contain inflammatory infiltrates. Immune cells have a broad impact on tumour initiation, growth and progression and many of these effects are mediated by proinflammatory cytokines. Among these cytokines, the pro-tumourogenic function of tumour necrosis factor (TNF) and interleukin 6 (IL-6) is well established. The role of TNF and IL-6 as master regulators of tumour-associated inflammation and tumourigenesis makes them attractive targets for adjuvant treatment in cancer.