CXCL8 and breast cancer: In contrast to these results, Green and coworkers [12] did not observe any correlation between the cytokines IL-1α, IL-1β, IL-4, IL-6, IL-8, TNF-α, TNF-β, IL-2, IL-5, IL-7 and IFN-γ and tumour histological grade, patient age or lymph node metastasis in breast cancer patients, but that study analyzed only RNA levels.