IL33 and cancer: It was also noted that the level of desmoplasia, a fibrotic reaction often promoted by cancer-associated fibroblasts and a negative prognostic factor in CRC [85,86], was inversely correlated with stromal ST2 levels, and positively correlated with epithelial IL-33 levels in a group of CRC patients, suggesting a possible role of IL-33/ST2 signaling in desmoplasia development and tumor progression [84].