This process is achieved by initial colonization of the bacteria which recruits abuntdant immune cells including macrophages and neutrophils via TLR4 signalling pathway and further activation of these immune cells triggered by TLR5 signalling mediated by the secretion of FlaB 74, Other engineered S. typhimurium expressing the cytokine LIGHT was injected intravenously to mice models of both primary and established pulmonary metastases, carrying out anti-tumour effects by binding to LIGHT receptors, transducing signals to induce the expression of chemokines 75. Here, TLR4 is linked to neoplasm.