Differential expression of microRNA-320a, -145, and -192 along the continuum of normal mucosa to high-grade dysplastic adenomas of the colorectum

Background: MicroRNA (miR)-320a, miR-145, and miR-192 have been shown to play a role in colorectal carcinogenesis and metastasis. We examined if there is a difference in expression during the histologic progression from normal mucosa (NM) to high-grade dysplastic adenomas (HG). Methods: Genome-wide miRNA expression profiling was performed on 113 colon adenomas. Information included histologic type, tumor grade, location, sex, age, family, and smoking history. A 2-way ANOVA was performed to evaluate the effect of the following factors adjusted for scan dates: location, sex, age, family history, smoking, and histology. Results: The expression of miR-320a increased; miR-145 and miR-192 expression decreased (P <.0001), with higher histologic grade, and were independent of age, sex, family history, and smoking status. Conclusions: The miRs studied had statistically significant changes in expression with progression of histologic grade. These changes may signify progression of normal mucosa to HG and potentially serve as early markers for disease progression and differentiating high- from low-risk adenomas.