The image visualizes the interaction between colon cancer stem cells and their surrounding "niche" cells. Engineered Lgr5-GFP; AKP colon cancer organoids were orthotopically transplanted to Rspo3-GFP; Grem1-tdTomato reporter mice. The researchers collected the primary tumors 4 weeks after the transplantation. This image shows 1)  heterogeneity of Lgr5+ colon cancer stem cells and Lgr5- differentiated cells, and 2)  expansion of Grem1-producing and/or RSPO3-producing surrounding “niche” cells. Visualization of cancer stem cells and their surrounding “niche” cells allows us to understand their complex interaction.