In this way, the objective of this work was to ascertain the role of anti-inflammatory cytokines, IL-4 and IL-10, and proinflammatory cytokines, IL-6 and TNF-α, in mammary tumors of female dogs and to correlate these results with the gene and protein expression of NF-κB. In addition, we sought to verify the correlation of these cytokines with clinicopathological parameters, cancer progression, and overall survival, to determine their prognostic value in mammary tumors. This evidence concerns the gene NFKB1 and breast cancer.