miR-24-2 controls H2AFX expression regardless of gene copy number alteration and induces apoptosis by targeting antiapoptotic gene BCL-2: a potential for therapeutic intervention.
Niloo Srivastava,Siddharth Manvati,Siddharth Manvati,Archita Srivastava,Ranjana Pal,Ponnusamy Kalaiarasan,Ponnusamy Kalaiarasan,Shilpi Chattopadhyay,Sailesh Gochhait,Raina Dua,Rameshwar N. K. Bamezai,Rameshwar N. K. Bamezai +11 more
TLDR
It was observed that H2AX gene expression was negatively correlated with miR-24-2 expression and not in accordance with the gene copy number status, both in cell lines and in sporadic breast tumor tissues, suggesting the potentiating effect of mir- 24-2-mediated apoptotic induction in human cancer cell lines treated with anticancer drugs.Abstract:
New levels of gene regulation with microRNA (miR) and gene copy number alterations (CNAs) have been identified as playing a role in various cancers. We have previously reported that sporadic breast cancer tissues exhibit significant alteration in H2AX gene copy number. However, how CNA affects gene expression and what is the role of miR, miR-24-2, known to regulate H2AX expression, in the background of the change in copy number, are not known. Further, many miRs, including miR-24-2, are implicated as playing a role in cell proliferation and apoptosis, but their specific target genes and the pathways contributing to them remain unexplored. Changes in gene copy number and mRNA/miR expression were estimated using real-time polymerase chain reaction assays in two mammalian cell lines, MCF-7 and HeLa, and in a set of sporadic breast cancer tissues. In silico analysis was performed to find the putative target for miR-24-2. MCF-7 cells were transfected with precursor miR-24-2 oligonucleotides, and the gene expression levels of BRCA1, BRCA2, ATM, MDM2, TP53, CHEK2, CYT-C, BCL-2, H2AFX and P21 were examined using TaqMan gene expression assays. Apoptosis was measured by flow cytometric detection using annexin V dye. A luciferase assay was performed to confirm BCL-2 as a valid cellular target of miR-24-2. It was observed that H2AX gene expression was negatively correlated with miR-24-2 expression and not in accordance with the gene copy number status, both in cell lines and in sporadic breast tumor tissues. Further, the cells overexpressing miR-24-2 were observed to be hypersensitive to DNA damaging drugs, undergoing apoptotic cell death, suggesting the potentiating effect of mir-24-2-mediated apoptotic induction in human cancer cell lines treated with anticancer drugs. BCL-2 was identified as a novel cellular target of miR-24-2. mir-24-2 is capable of inducing apoptosis by modulating different apoptotic pathways and targeting BCL-2, an antiapoptotic gene. The study suggests that miR-24-2 is more effective in controlling H2AX gene expression, regardless of the change in gene copy number. Further, the study indicates that combination therapy with miR-24-2 along with an anticancer drug such as cisplatin could provide a new avenue in cancer therapy for patients with tumors otherwise resistant to drugs.read more
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References
More filters
Journal ArticleDOI
Analysis of relative gene expression data using real-time quantitative pcr and the 2(-delta delta c(t)) method
TL;DR: The 2-Delta Delta C(T) method as mentioned in this paper was proposed to analyze the relative changes in gene expression from real-time quantitative PCR experiments, and it has been shown to be useful in the analysis of realtime, quantitative PCR data.
Journal ArticleDOI
DNA Double-stranded Breaks Induce Histone H2AX Phosphorylation on Serine 139
TL;DR: In this paper, a histone H2AX species that has been phosphorylated specifically at serine 139 was found to be a major component of DNA double-stranded break.
Journal ArticleDOI
The mdm-2 oncogene product forms a complex with the p53 protein and inhibits p53-mediated transactivation
TL;DR: A product of the mdm-2 oncogene forms a tight complex with the p53 protein, and the mDM-2oncogene can inhibit p53-mediated transactivation.
Journal ArticleDOI
Large-Scale Copy Number Polymorphism in the Human Genome
Jonathan Sebat,B. Lakshmi,Jennifer Troge,Joan Alexander,Janet M. Young,Pär Lundin,Susanne Månér,Hillary Massa,Megan Walker,Maoyen Chi,Nicholas Navin,Robert Lucito,John Healy,James W. Hicks,Kenny Q. Ye,Andrew Reiner,T. Conrad Gilliam,Barbara J. Trask,Nick Patterson,Anders Zetterberg,Michael Wigler +20 more
TL;DR: It is shown that large-scale copy number polymorphisms (CNPs) (about 100 kilobases and greater) contribute substantially to genomic variation between normal humans.
Journal ArticleDOI
Megabase chromatin domains involved in DNA double-strand breaks in vivo.
TL;DR: The results offer direct visual confirmation that γ-H2AX forms en masse at chromosomal sites of DNA double-strand breaks and suggest the possible existence of units of higher order chromatin structure involved in monitoring DNA integrity.