TLR4 and colon dysplasia: Levels of P. anaerobius are higher in human colon tumor tissues and adenomas compared with nontumor tissues; this bacterium increases colon dysplasia in a colorectal cancer mouse model. P. anaerobius interacts with TLR2 and TLR4 in colon cells to increase the abundance of reactive oxidative species, which promotes cholesterol synthesis and cell proliferation.