MicroRNA Signatures as Novel Biomarkers in Small Intestine Neuroendocrine Tumors Abstract #355

Introduction: Small intestine (SI) neuroendocrine tumors (NET) arise from serotonin-producing intraepithelial cells in the SI referred to as enterochromafin cells. The detection of SI-NETs is often concomitant with the appearance of hepatic metastasis thus most patients with SI-NET have metastases at initial presentation. MicroRNAs (miRs) are post-transcriptional key regulators in tumorigenesis which regulate expression of other genes. Little evidence of miR expression or deregulation in SI-NETs has been reported.
Aim(s): To explore miR expression of SI-NET cells at different stages of disease and uncover the role miRs in the development of SI-NETs.
Materials and methods: Microdissected normal enterochromaffin cells and SI-NET tissues were miRs profiled. Results were confirmed by QRT-PCR and Northern Blot analysis. A miR target genes list was retrieved using TargetScan.

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