IL17A and colorectal carcinoma: These results are in agreement with our previous data indicating increased Il17a transcript levels in CRC lesions of St2−/− versus WT mice (mean relative expression: 2.99 × 10−2 ± 9.25 × 10−3 versus 3.98 × 10−4 ± 1.44 × 10−4, P < 0.01; n = 9 and 8, respectively).16 Therefore, IL-33 appears to restrain the conversion of CD4+ T cells into IL-17-producing cells, also during intestinal tumorigenesis.