Serum MicroRNA profile in patients with colon adenomas or cancer

Background: Colon cancer, one of the most common causes of cancer-related deaths, arises from adenomatous polyps. In these years, circulating microRNAs (miRNAs) have attracted increasing attention as novel biomarkers for colon cancers. The dysregulated circulating miRNAs in patients with colon adenomas has not been well-understood. Methods: Here, we aimed to identify miRNA profile in the serum of patients with colon adenomas or colon cancer by using microarray. Then we validated eight differentially expressed miRNAs (DEMs) by qRT-PCR and predicted their targets. Results: We identified 26 DEMs from Adenomas versus Normal comparison (11 up-regulations and 15 down-regulations), 72 DEMs from Cancer versus Normal comparison (19 up-regulations and 53 down-regulations) and 17 DEMs from Cancer versus Adenomas comparison (4 up-regulations and 13 down-regulations). Moreover, three DEMs identified from Cancer versus Normal comparison were included in the list of DEMs identified from Cancer versus Adenomas comparison, and may be specific diagnostic biomarkers for colon cancer. Five down-regulated miRNAs identified from Cancer versus Normal comparison were included in the list of DEMs identified from Adenomas versus Normal comparison, and may be important for the development of colon polyps and cancer. Conclusions: We discovered 8 circulating miRNAs associated with colon adenomas and colon cancer, and these miRNAs may potentially serve as noninvasive screening biomarkers for colon cancer. Our study is useful for expanding our understanding in the development of colon adenomas and colon cancer, and thus provide novel insights into colon cancer pathogenesis and prevention.