For example, a study which used APCmin- and azoxymethane (AOM)-based intestinal tumor models revealed the emergence of a peri-cryptal prostaglandin endoperoxide synthase 2 (PTGS2)-expressing fibroblast subpopulation that contributes to the proliferation of tumor-initiating stem cells (TISCs), thereby promoting intestinal tumorigenesis (Roulis et al. 2020). The gene discussed is PTGS2; the disease is neoplasm.