TLR4 and breast cancer: Additional immunological relevant factors that affect the prognosis of breast cancer patients include loss-of-function alleles of pattern recognition receptors (such as toll like receptor 4 (TLR4) and purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7) [12, 13] and the local expression of genes [such as myxovirus (influenza virus) resistance 1 (MX1)]) that are tied to the type 1 interferon response [14].