CXCL8 and osteosarcoma: In a study that evaluated interleukin (IL)-2, IL-4, IL-8, interferon (IFN)-γ, and TNF-α concentrations at the time of diagnosis in children with osteosarcoma, the following concentrations of peripheral blood cytokines were observed: IL-2 10.7 pg/mL, IFN-γ 1.3 pg/mL, TNF-α 28.3 pg/mL, IL-4 2.0 pg/mL, and IL-8 13.5 pg/mL [51].