The pivotal role of cytokines in liver disease pathogenesis and therapeutic potential

Liver disease is a major threat to human health and life safety, primarily encompassing hepatitis caused by various factors (viral, alcoholic, fatty and autoimmune hepatitis), cirrhosis and liver cancer. Cytokines are molecules found on cell membranes that mediate the inflammation, immunity and a range of cellular functions, such as cell differentiation, proliferation, metastasis and apoptosis. In general, the delicate balance between pro- and anti-inflammatory effects is maintained by the body's regulatory mechanisms. Once this balance is disturbed, complex chain reactions can occur, including systemic injury, tumor, multi-organ failure or death, resulting in the release of cytokines. This review mainly focuses on the classification, biological characteristics, pathogenesis, signaling pathways of various cytokines (interleukins, interferons, tumor necrosis factor, colony-stimulating factors, chemokines and growth factors) and their important roles in the occurrence and development of different liver diseases, mediating the immune responses, and further discusses the application prospects of cytokines in the clinical treatments of liver diseases.