Despite the limitations and the need for further confirmatory studies, this work allowed us to search the Achilles heel of FOXP3 and identify short sequences within the leucin zipper, the AML1 binding region, or the FKH domain that could be considered as potential hits (Figure 8) for the development of first-in-class molecules to inhibit FOXP3 with potential for the development of new therapies against cancer. This evidence concerns the gene FOXP3 and cancer.