An alternative approach in regulation of expression of a transgene by endogenous miR-145 in carcinoma and normal breast cell lines.
MicroRNAs are small noncoding RNAs that regulate gene expression by repressing translation of target cellular transcripts. Increasing evidences indicate that miRNAs have different expression profiles and play crucial roles in numerous cellular processes. Delivery and expression of transgenes for cancer therapy must be specific for tumors to avoid killing of healthy tissues. Many investigators have shown that transgene expression can be suppressed in normal cells using vectors that are responsive to microRNA regulation. To overcome this problem, miR-145 that exhibits downregulation in many types of cancer cells was chosen for posttranscriptional regulatory systems mediated by microRNAs. In this study, a psiCHECK-145T vector carrying four tandem copies of target sequences of miR-145 into 3'-UTR of the Renilla luciferase gene was constructed. Renilla luciferase activity from the psiCHECK-145T vector was 57% lower in MCF10A cells with high miR-145 expression as compared to a control condition. Additionally, overexpression of miR-145 in MCF-7 cells with low expression level of miR-145 showed more than 76% reduction in the Renilla luciferase activity from the psiCHECK-145T vector. Inclusion of miR-145 target sequences into the 3'-UTR of the Renilla luciferase gene is a feasible strategy for restricting transgene expression in a breast cancer cell line while sparing a breast normal cell line.
Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Maryam
M
Ghanbari Safari
Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.
Kazem
K
Baesi
Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Saman
S
Hosseinkhani
D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D049410:Luciferases, Renilla / Q000096:biosynthesis / Q000235:genetics*; D061986:MCF-7 Cells; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D019076:Transgenes
C541010:MIRN145 microRNA, human; D035683:MicroRNAs; D049410:Luciferases, Renilla
Renilla luciferase; miR-145; microRNA regulation; transgene