Gene expression profiling of Trop2+ cells in mouse Apc-deficient small intestinal hyperplastic epithelium

Tumor Associated Calcium Signal Transducer 2 (TACSTD2) is one of the cancer-related genes whose overexpression correlates with tumor progression and invasiveness in human colorectal cancer. TACSTD2 gene encodes for a transmembrane glycoprotein TROP2, which is implicated in altered expression of epithelial-mesenchymal transition (EMT) markers and may play a role in metastasis formation. To monitor the onset of TROP2 in hyperplastic cells and its effect on aberrant signaling potentially leading to tumor growth, we isolated epithelial cells from the mouse small intestine 7 days after disruption of the Adenomatous polyposis coli (Apc) gene. Loss of APC tumor suppressor function is the most common initial step in the development of colon cancer in humans. In the mice, the epithelial hyperproliferation occurs within a few days after Apc disruption, accompanied by the formation of ectopic crypts, followed by the formation of microadenomas over time. We performed expression profiling of Trop2+ and Trop2- hyperproliferating cells and, in addition, non-proliferating cells of the intestinal epithelium, including predominantly differentiated cells.