title: Association of microRNA expression with microsatellite instability status in colorectal adenocarcinoma.
abstract: MicroRNAs (miRNA), small noncoding RNAs, are potential diagnostic and prognostic markers, as well as therapeutic targets. miRNA profiles of colorectal carcinomas have not been studied extensively in the context of microsatellite instability (MSI) status. We therefore evaluated 55 paired colorectal adenocarcinomas (CRC) and non-neoplastic mucosa samples using a panel of 24 miRNAs selected by literature review and prior studies in our laboratory. Stem-loop reverse transcriptase quantitative (real-time) polymerase chain reaction assays were done on RNA extracted from formalin-fixed, paraffin-embedded tissue of resection specimens. When miRNA expression was compared with clinicopathologic features and MSI status, eleven miRNAs (miR-183, -31, -20, -25, -92, -93, -17, -135a, -203, -133b, and -223) were over-expressed in CRC relative to mucosa, and nine (miR-192, -215, -26b, -143, -145, -191, -196a, -16, and let-7a) were under-expressed in CRC. Relative expression of miR-92, -223, -155, -196a, -31, and -26b were significantly different among MSI subgroups, and miR-31 and miR-223 were overexpressed in CRC of patients with hereditary non-polyposis colorectal cancer syndrome (Lynch syndrome). Our findings indicate that miRNA expression in CRC is associated with MSI subgroups, including low MSI and HNPCC-associated cancers, and that miRNAs may have posttranscriptional gene regulatory roles in these MSI subgroups and possible effects on the clinicopathologic and biomarker characteristics.
authors.affiliation: Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, 8515 Fannin St, NAO1.061a, Houston, Texas 77054, USA.
authors.forename: Jonathan S L
authors.initials: JS
authors.lastname: Earle
authors.forename: Rajyalakshmi
authors.initials: R
authors.lastname: Luthra
authors.forename: Angela
authors.initials: A
authors.lastname: Romans
authors.forename: Ronald
authors.initials: R
authors.lastname: Abraham
authors.forename: Joe
authors.initials: J
authors.lastname: Ensor
authors.forename: Hui
authors.initials: H
authors.lastname: Yao
authors.forename: Stanley R
authors.initials: SR
authors.lastname: Hamilton
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001681:Biological Assay; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism / Q000473:pathology; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D053842:Microsatellite Instability; D008875:Middle Aged
chemical_list: D035683:MicroRNAs