TLR4 and colonic neoplasm: First of all, incubation of HT-29 cells only with LPS determines a significant stimulation of all analyzed interleukins compared to untreated cells due to the stimulation of Toll Like Receptor type 4 (TLR4) expressed on the membrane of human colon cancer cells leading to an upregulation of interleukins expression mRNA and their secretion [14].