Differential gene expression in Lrig1null duodenal tumors compared to normal duodenum

Leucine-rich repeats and immunoglobulin-like domains 1 (Lrig1) is a pan-ErbB negative regulator and intestinal stem cell marker downregulated in many malignancies. Over 91% Lrig1-CreERT2/CreERT2 (Lrig1-/-) mice developed duodenal adenomas, providing the first in vivo evidence Lrig1 acts as a tumor suppressor. We thus characterize the differential expressing transcripts in these duodenal adenomas to explore the pathegenesis. Elevated expression of the Egfr ligands was detected in adenomas compared to adjacent normal tissue. These adenomas also expressed the gastric-specific genes Gastrokine1 and Mucin5ac, indicating gastric metaplasia.

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