Noteworthy, the potential role of microbiome as a multileveled regulator of distinct TME segments is further illustrated by a recent study showing that gut microbiota regulate the expression of the addressin MAdCAM-1 in intestinal endothelial and lymphoid tissues, thus controlling the egress of enterotropic α4β7+/IL-17+ regulatory T cells to tumor tissues by modulating the interaction between MAdCAM-1 and α4β7 [214]. The gene discussed is MADCAM1; the disease is neoplasm.