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Hussain A, Ray MK. DEAD box RNA helicases protect Antarctic Pseudomonas syringae Lz4W against oxidative stress. Infect Genet Evol 2022; 106:105382. [PMID: 36336276 DOI: 10.1016/j.meegid.2022.105382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 10/28/2022] [Accepted: 11/02/2022] [Indexed: 11/06/2022]
Abstract
DEAD box RNA helicases are involved in important cellular processes like RNA metabolism (Processing and Degradation), ribosome biogenesis and translation. Besides being crucial to the formation of cold adapted degradosomes, RNA helicases have been implicated in structural rearrangement of RNA, implying a role in alleviation of RNA secondary structure stabilization at low temperature. This study depicts the results of experiments on protective role played by DEAD box RNA helicases against nucleic acid damaging agents. RNA helicase mutants ΔrhlE, ΔsrmB, ΔcsdA, ΔdbpA and ΔrhlB cells were exposed to various DNA damaging agents (UV, Paraquat, Mitomycin C, Hydroxyurea and Hydrogen peroxide) and assessed for sensitivity to them. Our results illustrate that ∆csdA displayed sensitivity to paraquat (that causes oxidative damage) and UV radiation induced DNA damage. On the other hand, ∆srmB displays sensitivity to hydroxyurea that causes damage to the replication forks (RFs) by inhibiting ribonucleotide reductase and depleting the dNTP pool of cells. However, all five RNA helicase mutants were resistant to H2O2 mediated oxidative stress and mitomycin C induced DNA cross-links.
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Affiliation(s)
- Ashaq Hussain
- Centre for Cellular and Molecular Biology, Hyderabad, India.
| | - Malay Kumar Ray
- Centre for Cellular and Molecular Biology, Hyderabad, India.
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Heerma van Voss MR, Schrijver WAME, Ter Hoeve ND, Hoefnagel LD, Manson QF, van der Wall E, Raman V, van Diest PJ. The prognostic effect of DDX3 upregulation in distant breast cancer metastases. Clin Exp Metastasis 2016; 34:85-92. [PMID: 27999982 PMCID: PMC5285427 DOI: 10.1007/s10585-016-9832-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/01/2016] [Indexed: 02/01/2023]
Abstract
Metastatic breast cancer remains one of the leading causes of death in women and identification of novel treatment targets is therefore warranted. Functional studies showed that the RNA helicase DDX3 promotes metastasis, but DDX3 expression was never studied in patient samples of metastatic cancer. In order to validate previous functional studies and to evaluate DDX3 as a potential therapeutic target, we investigated DDX3 expression in paired samples of primary and metastatic breast cancer. Samples from 79 breast cancer patients with distant metastases at various anatomical sites were immunohistochemically stained for DDX3. Both cytoplasmic and nuclear DDX3 expression were compared between primary and metastatic tumors. In addition, the correlation between DDX3 expression and overall survival was assessed. Upregulation of cytoplasmic (28%; OR 3.7; p = 0.002) was common in breast cancer metastases, especially in triple negative (TN) and high grade cases. High cytoplasmic DDX3 levels were most frequent in brain lesions (65%) and significantly correlated with high mitotic activity and triple negative subtype. In addition, worse overall survival was observed for patients with high DDX3 expression in the metastasis (HR 1.79, p = 0.039). Overall, we conclude that DDX3 expression is upregulated in distant breast cancer metastases, especially in the brain and in TN cases. In addition, high metastatic DDX3 expression correlates with worse survival, implying that DDX3 is a potential therapeutic target in metastatic breast cancer, in particular in the clinically important group of TN patients.
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Affiliation(s)
- Marise R Heerma van Voss
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands.,Department of Radiology and Radiological Sciences, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | | | - Natalie D Ter Hoeve
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Laurien D Hoefnagel
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Quirine F Manson
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elsken van der Wall
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands.,Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Venu Raman
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands.,Department of Radiology and Radiological Sciences, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.,Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Paul J van Diest
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands. .,Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
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