The role of Nox4-derived ROS in mediating IL-6 and IL-8-dependent RCC cell invasion is supported by our findings that pretreatment of RCC cells with the antioxidant, NAC or the Nox inhibitor, DPI in addition to specific Nox4 silencing with siRNA reduces IL-6 and IL-8 production and this conditioned media is unable to stimulate RCC cell invasion when compared to hypoxia conditioned media. This evidence concerns the gene CXCL8 and renal cell carcinoma.