title: The effect of miR-340 over-expression on cell-cycle-related genes in triple-negative breast cancer cells.
abstract: Breast cancer is a heterogeneous disease, and among all types, triple-negative breast cancer (TNBC) is characterised by high risk of recurrence. The discovery of microRNAs (miRNA) has opened the door for targeted therapy of TNBC. miR-340 down-regulation and sub-G1-accumulated cells in flowcytometry were observed in metastatic TNBC cells (data in publication), leading us to investigate the potential tumour suppressive role of this miRNA on cell-cycle-related genes. A lentiviral vector containing miR-340 was applied to over-express miR-340 in TNBC cell line, MDA-MB-231. Then, the expression of some cell-cycle-regulating genes including cyclin A2 (cyclin A2), Cyclin-dependent kinases 2 (CDK2), cyclin-dependent kinase inhibitors (P16, P18 and P27), Retinoblastoma (RB) and transcription factors (SMAD 4, SOX2 and SOX17) was investigated using quantitative RT-PCR. The results showed a decline in the expression of SOX2, P16 and P27 after miR-340 over-expression, whereas we observed an increase in the expression of cyclin A2, CDK2, SOX17, P18, SMAD 4 and RB. The over-expression of tumour suppressor genes such as RB and SOX17 and down-regulation of an oncogene such as SOX2 were in accordance to the inhibitory role of miR-340 that causes blockage of breast cancer metastasis which should be further investigated.
authors.affiliation: Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.|Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Mohammadi Yeganeh
authors.affiliation: Department of Pathology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Vasei
authors.affiliation: Department of Molecular Biology and Genetic Engineering, Stem Cell Technology Research Center, Tehran, Iran.
authors.forename: R
authors.initials: R
authors.lastname: Tavakoli
authors.affiliation: Department of Medical Biotechnology and Nanotechnology, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
authors.forename: V
authors.initials: V
authors.lastname: Kia
authors.affiliation: Department of Research and Development, Production and Research Complex, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Paryan
mesh_terms: D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D056751:Cyclin A2 / Q000235:genetics; D051357:Cyclin-Dependent Kinase 2 / Q000235:genetics; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics; D050763:Cyclin-Dependent Kinase Inhibitor p18 / Q000235:genetics; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D005822:Genetic Vectors; D006801:Humans; D016086:Lentivirus; D035683:MicroRNAs / Q000235:genetics*; D009362:Neoplasm Metastasis; D016160:Retinoblastoma Protein / Q000235:genetics; D055748:SOXB1 Transcription Factors / Q000235:genetics; D055760:SOXF Transcription Factors / Q000235:genetics; D051901:Smad4 Protein / Q000235:genetics; D064726:Triple Negative Breast Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: C503721:CCNA2 protein, human; D056751:Cyclin A2; D019941:Cyclin-Dependent Kinase Inhibitor p16; D050763:Cyclin-Dependent Kinase Inhibitor p18; C570046:MIRN340 microRNA, human; D035683:MicroRNAs; D016160:Retinoblastoma Protein; C497796:SMAD4 protein, human; C109188:SOX17 protein, human; C527782:SOX2 protein, human; D055748:SOXB1 Transcription Factors; D055760:SOXF Transcription Factors; D051901:Smad4 Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2
keywords: cell-cycle genes; cyclin-dependent kinase; cyclin-dependent kinase inhibitor; miRNA; triple-negative breast cancer