microRNA-7 inhibits the epidermal growth factor receptor and the Akt pathway and is down-regulated in glioblastoma

• Published in: Cancer research (Chicago, Ill.) Ill.), 2008-05, Vol.68 (10), p.3566-3572
• Main Authors: Kefas, Benjamin, Godlewski, Jakub, Comeau, Laurey, Li, Yunqing, Abounader, Roger, Hawkinson, Michael, Lee, Jeongwu, Fine, Howard, Chiocca, E Antonio, Lawler, Sean, Purow, Benjamin
• Format: Article
• Language: English
• Subjects: 3' Untranslated Regions; Brain Neoplasms - metabolism; Cell Line, Tumor; Cell Proliferation; Cell Separation; Down-Regulation; Flow Cytometry; Gene Expression Regulation, Neoplastic; Glioblastoma - metabolism; HeLa Cells; Humans; MicroRNAs; Proto-Oncogene Proteins c-akt - metabolism; Transfection
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/0008-5472.can-07-6639

microRNAs are noncoding RNAs inhibiting expression of numerous target genes, and a few have been shown to act as oncogenes or tumor suppressors. We show that microRNA-7 (miR-7) is a potential tumor suppressor in glioblastoma targeting critical cancer pathways. miR-7 potently suppressed epidermal growth factor receptor expression, and furthermore it independently inhibited the Akt pathway via targeting upstream regulators. miR-7 expression was down-regulated in glioblastoma versus surrounding brain, with a mechanism involving impaired processing. Importantly, transfection with miR-7 decreased viability and invasiveness of primary glioblastoma lines. This study establishes miR-7 as a regulator of major cancer pathways and suggests that it has therapeutic potential for glioblastoma.