title: microRNA-27a functions as a tumor suppressor in esophageal squamous cell carcinoma by targeting KRAS.
abstract: microRNAs (miRNAs) have been suggested to play a vital role in regulating tumor progression and invasion. However, the expression of miR-27a in esophageal squamous cell carcinoma (ESCC) and its effect on the tumorigenesis of ESCC are unclear. In the present study, we found that miR-27a was downregulated in esophageal carcinoma cell lines and ESCC specimens with lymph node metastasis. Furthermore, we demonstrated that miR-27a binds to the 3'-untranslated region (UTR) of KRAS and inhibits the expression of the KRAS protein. miR-27a levels were inversely correlated with levels of KRAS mRNA and protein in ESCC specimens. Both in vitro and in vivo assays revealed that miR-27a attenuated ESCC proliferation, invasion and tumor growth in nude mice. miR-27a exerts its tumor suppressor function through inhibition of the KRAS-related ERK pathways. Our findings suggest, for the first time, that miR-27a suppresses tumorigenesis of ESCC by targeting KRAS.
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, P.R. China.
authors.forename: Linan
authors.initials: L
authors.lastname: Zhu
authors.forename: Zhiju
authors.initials: Z
authors.lastname: Wang
authors.forename: Qingxia
authors.initials: Q
authors.lastname: Fan
authors.forename: Ruilin
authors.initials: R
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000473:pathology; D015536:Down-Regulation; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000473:pathology; D000077277:Esophageal Squamous Cell Carcinoma; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D016147:Genes, Tumor Suppressor; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D035683:MicroRNAs / Q000235:genetics / Q000502:physiology*; D009361:Neoplasm Invasiveness / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; C117307:KRAS protein, human; C531388:MIRN27 microRNA, human; D035683:MicroRNAs; D011518:Proto-Oncogene Proteins; D048049:Extracellular Signal-Regulated MAP Kinases; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins