IL-11 is known to promote the development of colorectal cancer in humans and mice, but when and where IL-11 is expressed during cancer development is unknown. “To address these questions experimentally, we generated reporter mice that express the green fluorescent protein (EGFP) gene in interleukin 11 (IL-11)-producing (IL11+) cells in vivo. We found IL-11+ cells in the colons of this murine colitis-associated colorectal cancer model,” said Dr. Nishina, the lead author of a study published April 16 in Nature Communications. “The IL-11+ cells were absent from the colon under normal conditions but rapidly appeared in the tissues of mice with colitis and colorectal cancer.”