MicroRNA profiling differentiates colorectal cancer according to KRAS status

• DOI: 10.1002/gcc.20925
• Publication Date: 2011-09-16T00:28:00Z
• Authors: Neda Mosakhani; Virinder Kaur Sar...; Ioana Borze; Marja‐Liisa Karja...; Jari Sundström; Raija Ristamäki; Pia Österlund; Sakari Knuutila
• Keywords: Male; Proto-Oncogene Proteins B-raf; 0301 basic medicine; Gene Expression Profiling; Reproducibility of Results; Middle Aged; ta3111; 3. Good health; Gene Expression Regulation, Neoplastic; Proto-Oncogene Proteins p21(ras); MicroRNAs; 03 medical and health sciences; Proto-Oncogene Proteins; Mutation; ras Proteins; Humans; Female; Colorectal Neoplasms; ta999; Aged; Signal Transduction

AbstractRecent studies have shown the important role of microRNAs (miRNAs) in a variety of biological processes, and in its ability to distinguish tumors according to their prognostic and predictive properties. To identify miRNA signatures associated with colorectal carcinoma (CRC) and with KRAS status, we studied, using Agilent's miRNA microarrays, miRNA expression in primary tumors from 55 metastatic CRC patients, including 15 with mutant and 40 with wild‐type KRAS. Comparing these with normal colon tissue, we identified 49 miRNAs—including 19 novel miRNAs—significantly deregulated in tumor tissue. The presence of the KRAS mutation was associated with up‐regulation of miR‐127‐3p, miR‐92a, and miR‐486‐3p and down‐regulation of miR‐378. Increased expression of miR‐127‐3p and miR‐92a in KRAS mutant tumors was significantly confirmed by quantitative reverse transcriptase polymerase chain reaction (qRT‐PCR) (P < 0.05). We identified some predicted target genes of differentially expressed miRNAs between mutated and wild‐type KRAS, such as RSG3 and TOB1, which are involved in apoptosis and proliferation. Target prediction and pathway analysis suggest a possible role for deregulated miRNAs in nicotinamide adenine dinucleotide phosphate (NADPH) regeneration and G protein‐coupled receptor signaling pathways. © 2011 Wiley Periodicals, Inc.