ABSTRACT
BACKGROUND: Whole transcriptome RNA variant analyses have shown that adenosine deaminases acting on RNA ( ADAR ) enzymes modify a large proportion of cellular RNAs, contributing to transcriptome diversity and cancer evolution. Despite the advances in the understanding of ADAR function in breast cancer, ADAR RNA editing functional consequences are not fully addressed. RESULTS: We characterized A to G(I) mRNA editing in 81 breast cell lines, showing increased editing at 3'UTR and exonic regions in breast cancer cells compared to immortalized non-malignant cell lines. In addition, tumors from the BRCA TCGA cohort show a 24% increase in editing over normal breast samples when looking at 571 well-characterized UTRs targeted by ADAR1. Basal-like subtype breast cancer patients with high level of ADAR1 mRNA expression shows a worse clinical outcome and increased editing in their 3'UTRs. Interestingly, editing was particularly increased in the 3'UTRs of ATM, GINS4 and POLH transcripts in tumors, which correlated with their mRNA expression. We confirmed the role of ADAR1 in this regulation using a shRNA in a breast cancer cell line (ZR-75-1). CONCLUSIONS: Altogether, these results revealed a significant association between the mRNA editing in genes related to cancer-relevant pathways and clinical outcomes, suggesting an important role of ADAR1 expression and function in breast cancer.
Subject(s)
Humans , Female , Breast Neoplasms/genetics , Adenosine Deaminase/genetics , RNA-Binding Proteins/genetics , RNA Editing/genetics , Untranslated Regions/genetics , RNA Stability/genetics , Breast Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Adenosine Deaminase/metabolism , RNA-Binding Proteins/metabolism , Gene Expression Profiling , RNA Stability/physiology , Cell Line, TumorABSTRACT
El desarrollo de técnicas que permitan editar o corregir con precisión y eficiencia el genoma de células vivas es uno de los objetivos principales de la investigación biomédica. En las últimas décadas se han investigado e implementado distintas herramientas de edición genómica entre las cuales se destaca el sistema CRISPR/Cas9, un mecanismo de defensa bacteriano que ha sido adaptado y rediseñado para su utilización en otros modelos celulares. La accesibilidad, técnica y económica, y el enorme potencial de CRISPR/Cas9 han dado lugar a una revolución casi sin precedentes en las ciencias biomédicas y representan un gran avance en el campo de la terapia génica que requiere, sin embargo, la cautela apropiada.
The development of techniques that allow the precise and efficient edition of the genome of living cells is one of the main goals of biomedical research. Over the last few decades, a number of genome editing tools have been developed, the most prominent being the CRISPR/Cas9 system, a bacterial defense mechanism that has been redesigned for its use in other cellular systems. The accessibility, both technical and economical, and the enormous potential of CRISPR/Cas9 have contributed to an almost unprecedented revolution in the biomedical sciences and represent an important step forward in the field of gene therapy that needs, however, to be taken cautiously.
Subject(s)
Humans , Animals , Genetic Therapy , Genetic Engineering , CRISPR-Cas Systems/genetics , RNA Editing/genetics , Gene EditingABSTRACT
Interleukin (IL)-12 activates T helper (Th) 1 cells to produce interferon (IFN)-gamma which inhibits atopic inflammation. IL-12 acts through interaction with its receptor, especially beta2 subunit. In several studies, the low production of IFN-gamma in peripheral mononuclear cells of atopic patients on response to IL-12 stimulation has been reported. Therefore we investigated the IL-12 receptor beta2 (IL-12R beta2) mRNA expression and RNA editing, nucleotide 2451 C-to-U conversion, to find the cause of low responsiveness to IL-12 in atopy. Quantitative real time PCR for mRNA expression and sequence analysis for RNA editing were performed in 80 atopic patients and 54 healthy controls. The expression of IL-12R beta2 mRNA was significantly lower in atopic patients than healthy controls (p<0.05). In sequence analysis, RNA editing on nucleotide 2451 was not found from either atopic patients or healthy controls. In additional evaluation, there was no relationship between expression of IL-12R beta2 mRNA and serum total IgE or blood eosinophil count. Reduced IL-12R beta2 mRNA expression in atopic patients indicate the reduced capacity to respond to IL-12 which induce IFN-gamma production and this may contribute to Th2-skewed immune response in atopy.