Notably, more than 30% of CD4+ FOXP3+ Tregs in colonic tumors of BALB/c mice expressed ST2, versus 3% of CD4+ FOXP3- T cells (Fig. 2b), thus indicating that ST2 expression in the CD4+ T cell compartment was mainly restricted to FOXP3+ Tregs. This evidence concerns the gene IL1RL1 and colonic neoplasm.