title: Micro RNA 34a and Let-7a Expression in Human Breast Cancers is Associated with Apoptotic Expression Genes.
abstract: Breast cancer is the most common cause of cancer-related death among women in the whole world. MiR- 34a and let-7a are well known tumor suppressors that participate in the regulation of apoptosis, invasion and other cellular functions. In this study, expression of miR-34a, let-7a and apoptosis pathway genes such as Bcl-2, Caspase-3 and P53 were evaluated using quantitative real-time PCR in 45 paired samples of normal margin and tumor tissue collected from breast cancer patient at advanced stage (3-4). MiR-34a, let-7a, caspase-3 and P53 expression are reduced and Bcl-2 expression is increased within tumoral tissues in comparison with normal margin tissues. P53 expression directly or indirectly was correlated with miR-34a, let-7a, Bcl-2 and caspase-3 expression. In This study we found that MiR-34a and let-7a expression are reduced in the tumoral tissues. Down- regulation of these two molecules correlated with expression of genes associated with apoptosis. These results suggest that due to the correlation of miR-34a and let-7a with apoptotic and anti-apoptotic pathways these molecules could participate as regulators in advanced clinical stages of breast cancer and should be considered as markers for diagnosis, prognostic assessment and targeted therapy.
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran E-mail : behzad_im@yahoo.com.
authors.forename: Behzad
authors.initials: B
authors.lastname: Mansoori
authors.forename: Ali
authors.initials: A
authors.lastname: Mohammadi
authors.forename: Solmaz
authors.initials: S
authors.lastname: Shirjang
authors.forename: Elham
authors.initials: E
authors.lastname: Baghbani
authors.forename: Behzad
authors.initials: B
authors.lastname: Baradaran
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000235:genetics*; D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009367:Neoplasm Staging; D011379:Prognosis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D051017:Apoptosis Regulatory Proteins; D014408:Biomarkers, Tumor; C522425:MIRN34 microRNA, human; D035683:MicroRNAs; C487931:mirnlet7 microRNA, human