IL-6 and related cytokines as the critical lynchpins between inflammation and cancer

• The IL-6 family of cytokines includes IL-6, IL-11, IL-27, IL-31, LIF, OSM, CNTF, CT-1 and CLC.
• The IL-6 family of cytokines regulates cell proliferation, survival, migration, invasion, metastasis, angiogenesis and inflammation via gp130.
• The JAK-STAT3 pathway is the major pathway downstream of gp130 signaling.
• IL-6 and IL-11 are highly up-regulated in many cancers and are important mediators linking inflammation and cancer.
• IL-6 and IL-11 are potential therapeutic and preventive targets as well as prognostic factors in cancer.

Inflammatory responses play pivotal roles in cancer development, including tumor initiation, promotion, progression, and metastasis. Cytokines are now recognized as important mediators linking inflammation and cancer, and are therefore potential therapeutic and preventive targets as well as prognostic factors. The interleukin (IL)-6 family of cytokines, especially IL-6 and IL-11, is highly up-regulated in many cancers and considered as one of the most important cytokine families during tumorigenesis and metastasis. This review discusses molecular mechanisms linking the IL-6 cytokine family to solid malignancies and their treatment.