With the pioneering advances in gnotobiotic biology, such as that of Faith et al. [22], it is fitting to speculate that inoculation of mice (prior to tumor growth) with commensals that are known to induce proliferation of anti-inflammatory cells, such as Foxp3+ Treg, and commensals able to moderate levels of inflammatory signals will create an antitumorigenic mucosal environment, which will considerably impede tumor growth. This evidence concerns the gene FOXP3 and neoplasm.