PIWIL2 and colon mucinous adenocarcinoma: Furthermore, when we interrogated PIWIL2 expression levels in the TCGA dataset by UALCAN analysis, PIWIL2 loss was more prevalent in the mucinous adenocarcinoma subtype of colon cancer (Fig. 2E), which is found in 10-20% of colon cancer patients and is characterized by ≥50% of the tumor volume consisting of extracellular mucins (Fleming et al., 2012; Luo et al., 2019; Huang et al., 2021).