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Keller LML, Flattich K, Weber-Ban E. Novel WYL domain-containing transcriptional activator acts in response to genotoxic stress in rapidly growing mycobacteria. Commun Biol 2023; 6:1222. [PMID: 38042942 PMCID: PMC10693628 DOI: 10.1038/s42003-023-05592-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/15/2023] [Indexed: 12/04/2023] Open
Abstract
The WYL domain is a nucleotide-sensing module that controls the activity of transcription factors involved in the regulation of DNA damage response and phage defense mechanisms in bacteria. In this study, we investigated a WYL domain-containing transcription factor in Mycobacterium smegmatis that we termed stress-involved WYL domain-containing regulator (SiwR). We found that SiwR controls adjacent genes that belong to the DinB/YfiT-like putative metalloenzymes superfamily by upregulating their expression in response to various genotoxic stress conditions, including upon exposure to H2O2 or the natural antibiotic zeocin. We show that SiwR binds different forms of single-stranded DNA (ssDNA) with high affinity, primarily through its characteristic WYL domain. In combination with complementation studies of a M. smegmatis siwR deletion strain, our findings support a role of the WYL domains as signal-sensing activity switches of WYL domain-containing transcription factors (WYL TFs). Our study provides evidence that WYL TFs are involved in the adaptation of bacteria to changing environments and encountered stress conditions.
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Affiliation(s)
| | - Kim Flattich
- Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Eilika Weber-Ban
- Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland.
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2
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Goel H, Goyal K, Pandey AK, Benjamin M, Khan F, Pandey P, Mittan S, Iqbal D, Alsaweed M, Alturaiki W, Madkhali Y, Kamal MA, Tanwar P, Upadhyay TK. Elucidations of Molecular Mechanism and Mechanistic Effects of Environmental Toxicants in Neurological Disorders. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2023; 22:84-97. [PMID: 35352654 DOI: 10.2174/1871527321666220329103610] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/08/2022] [Accepted: 02/08/2022] [Indexed: 02/08/2023]
Abstract
Due to rising environmental and global public health concerns associated with environmental contamination, human populations are continually being exposed to environmental toxicants, including physical chemical mutagens widespread in our environment causing adverse consequences and inducing a variety of neurological disorders in humans. Physical mutagens comprise ionizing and non-ionizing radiation, such as UV rays, IR rays, X-rays, which produces a broad spectrum of neuronal destruction, including neuroinflammation, genetic instability, enhanced oxidative stress driving mitochondrial damage in the human neuronal antecedent cells, cognitive impairment due to alterations in neuronal function, especially in synaptic plasticity, neurogenesis repression, modifications in mature neuronal networks drives to enhanced neurodegenerative risk. Chemical Mutagens including alkylating agents (EMS, NM, MMS, and NTG), Hydroxylamine, nitrous acid, sodium azide, halouracils are the major toxic mutagen in our environment and have been associated with neurological disorders. These chemical mutagens create dimers of pyrimidine that cause DNA damage that leads to ROS generation producing mutations, chromosomal abnormalities, genotoxicity which leads to increased neurodegenerative risk. The toxicity of four heavy metal including Cd, As, Pb, Hg is mostly responsible for complicated neurological disorders in humans. Cadmium exposure can enhance the permeability of the BBB and penetrate the brain, driving brain intracellular accumulation, cellular dysfunction, and cerebral edema. Arsenic exerts its toxic effect by induction of ROS production in neuronal cells. In this review, we summarize the molecular mechanism and mechanistic effects of mutagens in the environment and their role in multiple neurological disorders.
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Affiliation(s)
- Harsh Goel
- Department of Laboratory Oncology, All India Institute of Medical Sciences, New Delhi, India
| | - Keshav Goyal
- Division of Molecular and Cellular Biology, Faculty of Biology, Ludwig Maximilians Universitat, Munchen, Germany
| | - Avanish Kumar Pandey
- Department of Laboratory Oncology, All India Institute of Medical Sciences, New Delhi, India
| | - Mercilena Benjamin
- Department of Laboratory Oncology, All India Institute of Medical Sciences, New Delhi, India
| | - Fahad Khan
- Department of Biotechnology, Noida Institute of Engineering & Technology, 19, Knowledge Park-II, Institutional Area, Greater Noida, India
| | - Pratibha Pandey
- Department of Biotechnology, Noida Institute of Engineering & Technology, 19, Knowledge Park-II, Institutional Area, Greater Noida, India
| | - Sandeep Mittan
- Department of Cardiology, Ichan School of Medicine, Mount Sinai Hospital, One Gustave L. Levy Place, New York, USA
| | - Danish Iqbal
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al-Majmaah, 11952, Saudi Arabia
| | - Mohammed Alsaweed
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al-Majmaah, 11952, Saudi Arabia
| | - Wael Alturaiki
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al-Majmaah, 11952, Saudi Arabia
| | - Yahya Madkhali
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al-Majmaah, 11952, Saudi Arabia
| | - Mohammad Amjad Kamal
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, China
- King Fahd Medical Research Center, King Abdulaziz University, Saudi Arabia
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Bangladesh
- Enzymoics, 7 Peterlee Place, Hebersham NSW 2770, Novel Global Community Educational Foundation, Australia
| | - Pranay Tanwar
- Department of Laboratory Oncology, All India Institute of Medical Sciences, New Delhi, India
| | - Tarun Kumar Upadhyay
- Department of Biotechnology, Parul Institute of Applied Sciences and Cell Culture and Immunobiochemistry Lab, Centre of Research for Development, Parul University, Vadodara, Gujarat 391760, India
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3
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Wang Y, Wang J, Lv Q, He YK. ADH2/GSNOR1 is a key player in limiting genotoxic damage mediated by formaldehyde and UV-B in Arabidopsis. PLANT, CELL & ENVIRONMENT 2022; 45:378-391. [PMID: 34919280 DOI: 10.1111/pce.14249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
Maintenance of genome stability is an essential requirement for all living organisms. Formaldehyde and UV-B irradiation cause DNA damage and affect genome stability, growth and development, but the interplay between these two genotoxic factors is poorly understood in plants. We show that Arabidopsis adh2/gsnor1 mutant, which lacks alcohol dehydrogenase 2/S-nitrosoglutathione reductase 1 (ADH2/GSNOR1), are hypersensitive to low fluence UV-B irradiation or UV-B irradiation-mimetic chemicals. Although the ADH2/GSNOR1 enzyme can act on different substrates, notably on S-hydroxymethylglutathione (HMG) and S-nitrosoglutathione (GSNO), our study provides several lines of evidence that the sensitivity of gsnor1 to UV-B is caused mainly by UV-B-induced formaldehyde accumulation rather than other factors such as alteration of the GSNO concentration. Our results demonstrate an interplay between formaldehyde and UV-B that exacerbates genome instability, leading to severe DNA damage and impaired growth and development in Arabidopsis, and show that ADH2/GSNOR1 is a key player in combating these effects.
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Affiliation(s)
- Yu Wang
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Jinzheng Wang
- College of Life Sciences, Capital Normal University, Beijing, China
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| | - Qiang Lv
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Yi-Kun He
- College of Life Sciences, Capital Normal University, Beijing, China
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Rasgele PG, Gokalp FD, Kaya ST, Kekecoglu M, Acar MK. Investigation of genotoxic effects of rhododendron honey using three mammalian bioassays in vivo. Drug Chem Toxicol 2021; 45:2301-2310. [PMID: 34100323 DOI: 10.1080/01480545.2021.1935421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Rhododendron honey (RH) is obtained from the rhododendron plants are grown in many regions around the world, causes poisoning in humans due to the grayanotoxin (GTX) compound in its structure. It is used by the public as a therapeutic for some diseases. It was aimed to study the genotoxic and cytotoxic effects of RH in mouse bone-marrow and sperm cells by using three mammalian bioassays. 25, 50 and 75 mg kg-1 concentrations of RH given to male mice via gavage for 24 and 48 h treatment periods and its active ingredient Grayanatoxin (GTX-III) 0.01 mg kg-1 by i.p. injection. Chromosome aberrations (CA), polychromatic erythrocytes (PCE)/normochromatic erythrocytes (NCE), micronucleated polychromatic erythrocytes (MNPCE) and sperm abnormalities were investigated. The results demonstrated that all the tested concentrations of RH significantly induced total abnormal cell frequency including chromosomal breaks for two time periods. In the MN assay, 75 mg kg-1 RH and 0.01 mg kg-1 GTX-III significantly increased % MNPCE and significantly reduced PCE/NCE ratios after 24 and 48 h treatments on mice demonstrating potential genotoxic and cytotoxic effect. Although there was a concentration-related increase in the percentage of total sperm abnormalities, this increase was not statistically significant compared to control. As a result, microscopic genotoxicity and cytotoxicity marker tests showed that RH and its active ingredient GTX-III have potential genotoxic and cytotoxic effect on mice bone marrow cells. It is understood that RH that is used to treat some diseases by public, should be handled carefully and used in a controlled manner.HighlightsChromosome aberration, micronucleus and sperm morphology assays are recommended as reliable biological indicators.RH and its active ingredient GTX-III have potential genotoxic and cytotoxic effect on mice bone marrow cells.Significant changes were observed upon the treatment of 75 mg kg-1 MH for MN assay.
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Affiliation(s)
- Pinar Goc Rasgele
- Department of Biosystems Engineering, Faculty of Agriculture, Duzce University, Duzce, Turkey
| | - Fulya Dilek Gokalp
- Department of Biology, Faculty of Science, Trakya University, Edirne, Turkey
| | - Salih Tunc Kaya
- Department of Biology, Faculty of Science and Letters, Duzce University, Duzce, Turkey
| | - Meral Kekecoglu
- Department of Biology, Faculty of Science and Letters, Duzce University, Duzce, Turkey
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Postoperative peritoneal adhesion: an update on physiopathology and novel traditional herbal and modern medical therapeutics. Naunyn Schmiedebergs Arch Pharmacol 2020; 394:317-336. [PMID: 32979062 DOI: 10.1007/s00210-020-01961-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/06/2020] [Indexed: 02/06/2023]
Abstract
Postoperative peritoneal adhesion (PPA) is a serious clinical condition that affects the high percentage of patients after abdominal surgery. In this review, we have tried to focus on pathophysiology and different underlying signal pathways of adhesion formation based on recent progress in the molecular and cellular mechanisms. Also, the strategies, developed based on traditional herbal and modern medicines, to prevent and treat the PPA via regulation of the molecular mechanisms were investigated. The search engines such as Google Scholar, PubMed, Scopus, and Science Direct have been used to evaluate the current literature related to the pathogenesis of adhesion formation and novel products. Recently, different mechanisms have been defined for adhesion formation, mainly categorized in fibrin formation and adhesion fibroblast function, inflammation, and angiogenesis. Therefore, the suppression of these mechanisms via traditional and modern medicine has been suggested in several studies. While different strategies with encouraging findings have been developed, most of the studies showed contradictory results and were performed on animals. The herbal products have been introduced as safe and effective agent which can be considered in future preclinical and clinical studies. Although a wide range of therapeutics based on traditional and modern medicines have been suggested, there is no agreement in the efficacy of these methods to prevent or treat adhesion formation after surgeries. Further basic and clinical researches are still needed to propose the efficiency of recommended strategies for prevention and treatment of PPA.
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Koklesova L, Liskova A, Samec M, Qaradakhi T, Zulli A, Smejkal K, Kajo K, Jakubikova J, Behzadi P, Pec M, Zubor P, Biringer K, Kwon TK, Büsselberg D, Sarria GR, Giordano FA, Golubnitschaja O, Kubatka P. Genoprotective activities of plant natural substances in cancer and chemopreventive strategies in the context of 3P medicine. EPMA J 2020; 11:261-287. [PMID: 32547652 PMCID: PMC7272522 DOI: 10.1007/s13167-020-00210-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 05/16/2020] [Indexed: 12/12/2022]
Abstract
Severe durable changes may occur to the DNA structure caused by exogenous and endogenous risk factors initiating the process of carcinogenesis. By evidence, a large portion of malignancies have been demonstrated as being preventable. Moreover, the targeted prevention of cancer onset is possible, due to unique properties of plant bioactive compounds. Although genoprotective effects of phytochemicals have been well documented, there is an evident lack of articles which would systematically present the spectrum of anticancer effects by phytochemicals, plant extracts, and plant-derived diet applicable to stratified patient groups at the level of targeted primary (cancer development) and secondary (cancer progression and metastatic disease) prevention. Consequently, clinical implementation of knowledge accumulated in the area is still highly restricted. To stimulate coherent co-development of the dedicated plant bioactive compound investigation on one hand and comprehensive cancer preventive strategies on the other hand, the current paper highlights and deeply analyses relevant evidence available in the area. Key molecular mechanisms are presented to detail genoprotective and anticancer activities of plants and phytochemicals. Clinical implementation is discussed. Based on the presented evidence, advanced chemopreventive strategies in the context of 3P medicine are considered.
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Affiliation(s)
- Lenka Koklesova
- Department of Obstetrics and Gynecology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Alena Liskova
- Department of Obstetrics and Gynecology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Marek Samec
- Department of Obstetrics and Gynecology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Tawar Qaradakhi
- Institute for Health and Sport, Victoria University, Melbourne, VIC Australia
| | - Anthony Zulli
- Institute for Health and Sport, Victoria University, Melbourne, VIC Australia
| | - Karel Smejkal
- Department of Natural Drugs, Faculty of Pharmacy, Masaryk University, 612 42 Brno, Czech Republic
| | - Karol Kajo
- Department of Pathology, St. Elisabeth Oncology Institute, 812 50 Bratislava, Slovakia
- Biomedical Research Center, Slovak Academy of Sciences, 845 05 Bratislava, Slovakia
| | - Jana Jakubikova
- Biomedical Research Center SAS, Cancer Research Institute, Bratislava, Slovakia
| | - Payam Behzadi
- Department of Microbiology, College of Basic Sciences, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran
| | - Martin Pec
- Department of Medical Biology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Pavol Zubor
- Department of Gynecologic Oncology, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- OBGY Health & Care, Ltd., 01001 Zilina, Slovakia
| | - Kamil Biringer
- Department of Obstetrics and Gynecology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Taeg Kyu Kwon
- Department of Immunology and School of Medicine, Keimyung University, Dalseo-Gu, Daegu, 42601 Korea
| | - Dietrich Büsselberg
- Department of Physiology and Biophysics, Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, P.O. Box 24144, Doha, Qatar
| | - Gustavo R. Sarria
- Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Frank A. Giordano
- Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Olga Golubnitschaja
- Predictive, Preventive and Personalised (3P) Medicine, Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Peter Kubatka
- Department of Medical Biology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
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In Vitro Antigenotoxic, Antihelminthic and Antioxidant Potentials Based on the Extracted Metabolites from Lichen, Candelariella vitellina. Pharmaceutics 2020; 12:pharmaceutics12050477. [PMID: 32456266 PMCID: PMC7285106 DOI: 10.3390/pharmaceutics12050477] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/17/2020] [Accepted: 05/20/2020] [Indexed: 01/22/2023] Open
Abstract
Lichens have recently received great attention due to their pharmacological potentials. The antigenotoxic potential of C. vitellina extract (25 and 50 µg/mL) was assessed in normal human peripheral blood lymphocytes (HPBL) against Mitomycin C (MMC) co-treatments. Flow cytometric analyses of cell cycle distribution, as well as apoptosis (Annexin V/PI), revealed that the extract had significantly (p ≤ 0.05) ameliorated the MMC toxicity by reducing the apoptotic cells and normalized the cell cycle phases. C. vitellina exhibited antigenotoxicity by ameliorating the diminished mitotic index and DNA single-strand breaks caused by MMC. Herein, the hydromethanolic extract (80%) of Candelariella vitellina (Japan) lichen, exhibited very low cytotoxicity towards normal human peripheral lymphocytes (HPBL) with IC50 >1000 µg/mL. In order to explore the antihelminthic effect, Echinococcus granulosus protoscoleces were used in vitro. Eosin staining revealed significant (p ≤ 0.05) dose and time-dependent scolicidal effects of the extract confirmed by degenerative alterations as observed by electron scan microscopy. Furthermore, primary and secondary metabolites were investigated using GC-MS and qualitative HPLC, revealing the presence of sugars, alcohols, different phenolic acids and light flavonoids. Significant antioxidant capacities were also demonstrated by DPPH radical-scavenging assay. In conclusion, the promising antigenotoxic, antihelminthic and antioxidant potentials of C. vitellina extract encourage further studies to evaluate its possible therapeutic potency.
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Antigenotoxic, Anti-photogenotoxic, and Antioxidant Properties of Polyscias filicifolia Shoots Cultivated In Vitro. Molecules 2020; 25:molecules25051090. [PMID: 32121158 PMCID: PMC7179227 DOI: 10.3390/molecules25051090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/17/2020] [Accepted: 02/22/2020] [Indexed: 11/16/2022] Open
Abstract
Traditional medicinal plants are an important source of active compounds with potential antimutagenic activity. Polyscias filicifolia Bailey (Araliaceae) is a South Asian traditional herb used as an adaptogenic and cardiac drug. Extracts of P. filicifolia contain a wide range of biologically active compounds like phenolic acids and triterpenoid saponins. In the present study. antigenotoxic potential of three naturally occurring phenolic acids and extracts of P. filicifolia growing in vitro with the addition of elicitors was evaluated against direct (4-nitroquinoline-N-oxide (4NQO) and mitomycin C (MMC)) and indirect mutagens (2-aminoanthracene (2AA)). The evaluation was made using a bacterial umu-test. Moreover, the ability to prevent photogenotoxicity induced by chlorpromazine (CPZ) under UVA irradiation was measured. The phytochemical profiling of examined extracts revealed the presence of numerous compounds with the prevelance of chlorogenic, caffeic, and ferulic acid derivatives; however, saponin fractions were also determined. The antioxidant potential of extracts strictly correlated with their composition. The tested extracts exhibited high antigenotoxic activity if the assay was performed with 2AA and metabolic activation. Moreover, the extracts slightly decreased the MMC-induced genotoxicity. However, an increase of the genotoxic effect was observed in the assay performed with 4NQO. In addition, photo-antigenotoxic activity was observed. In our study, phenolic acids exhibited lower activity than the extracts.
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Liu J, Geng G, Liang G, Wang L, Luo K, Yuan J, Zhao S. A novel topoisomerase I inhibitor DIA-001 induces DNA damage mediated cell cycle arrest and apoptosis in cancer cell. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:89. [PMID: 32175382 DOI: 10.21037/atm.2019.12.138] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background DNA topoisomerase enzyme plays an essential role in controlling the DNA topology structure by binding to DNA and cutting the phosphate backbone of either one or both of the DNA strands. Here, we have identified a small molecule inhibitor, DIA-001, that directly binds to Topoisomerase 1 (Topo I) and promotes the Topo I-DNA adducts. Methods In this study, we investigated the antitumor effects of DIA-001 using MTS assay and colony formation. We examined cell cycle of tumor cells with DIA-001 treatment in vitro by flow cytometry. And we investigated DNA damage and cell cycle marker protein after treatment with DIA-001 at different concentration and time point by western blot. Immunofluorescence was performance to detect the nuclear foci. The effects of DIA-001 on Topo I and Topo II activities were examined by DNA relaxation assays. Results We demonstrate that DIA-001 inhibit DNA replication and arrest cell cycle progression at the G2/M phase by directly binds to Topo I and promotes the Topo I-DNA adducts. In addition, DIA-001 can activate the DNA damage response signaling cascade, resulting in apoptosis in treated cells. Conclusions Our findings show a novel compound for treatment of cancer cells with the potential as a chemotherapy candidate that is less toxic to normal cells.
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Affiliation(s)
- Jiaqi Liu
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Guohe Geng
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Guang Liang
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Ling Wang
- Department of Pharmacy, Fujian Provincial Hospital, Provincial Clinical College of Fujian Medical University, Fuzhou 350001, China
| | - Kuntian Luo
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Jian Yuan
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Shiguang Zhao
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, China
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Sharma RB, Darko C, Zheng X, Gablaski B, Alonso LC. DNA Damage Does Not Cause BrdU Labeling of Mouse or Human β-Cells. Diabetes 2019; 68:975-987. [PMID: 30833468 PMCID: PMC6477907 DOI: 10.2337/db18-0761] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 02/23/2019] [Indexed: 12/26/2022]
Abstract
Pancreatic β-cell regeneration, the therapeutic expansion of β-cell number to reverse diabetes, is an important goal. Replication of differentiated insulin-producing cells is the major source of new β-cells in adult mice and juvenile humans. Nucleoside analogs such as BrdU, which are incorporated into DNA during S-phase, have been widely used to quantify β-cell proliferation. However, reports of β-cell nuclei labeling with both BrdU and γ-phosphorylated H2A histone family member X (γH2AX), a DNA damage marker, have raised questions about the fidelity of BrdU to label S-phase, especially during conditions when DNA damage is present. We performed experiments to clarify the causes of BrdU-γH2AX double labeling in mouse and human β-cells. BrdU-γH2AX colabeling is neither an age-related phenomenon nor limited to human β-cells. DNA damage suppressed BrdU labeling and BrdU-γH2AX colabeling. In dispersed islet cells, but not in intact islets or in vivo, pro-proliferative conditions promoted both BrdU and γH2AX labeling, which could indicate DNA damage, DNA replication stress, or cell cycle-related intrinsic H2AX phosphorylation. Strategies to increase β-cell number must not only tackle the difficult challenge of enticing a quiescent cell to enter the cell cycle, but also achieve safe completion of the cell division process.
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Affiliation(s)
- Rohit B Sharma
- Diabetes Center of Excellence in the Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Christine Darko
- Diabetes Center of Excellence in the Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Xiaoying Zheng
- Diabetes Center of Excellence in the Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Brian Gablaski
- Diabetes Center of Excellence in the Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Laura C Alonso
- Diabetes Center of Excellence in the Department of Medicine, University of Massachusetts Medical School, Worcester, MA
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Paramasivam A, Raghunandhakumar S, Priyadharsini JV, Jayaraman G. In Vitro Anti-Neuroblastoma Activity of Thymoquinone Against Neuro-2a Cells via Cell-cycle Arrest. Asian Pac J Cancer Prev 2016; 16:8313-9. [PMID: 26745078 DOI: 10.7314/apjcp.2015.16.18.8313] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We have recently shown that thymoquinone (TQ) has a potent cytotoxic effect and induces apoptosis via caspase-3 activation with down-regulation of XIAP in mouse neuroblastoma (Neuro-2a) cells. Interestingly, our results showed that TQ was significantly more cytotoxic towards Neuro-2a cells when compared with primary normal neuronal cells. In this study, the effects of TQ on cell-cycle regulation and the mechanisms that contribute to this effect were investigated using Neuro-2a cells. Cell-cycle analysis performed by flow cytometry revealed cell-cycle arrest at G2/M phase and a significant increase in the accumulation of TQ-treated cells at sub-G1 phase, indicating induction of apoptosis by the compound. Moreover, TQ increased the expression of p53, p21 mRNA and protein levels, whereas it decreased the protein expression of PCNA, cyclin B1 and Cdc2 in a dose- dependent manner. Our finding suggests that TQ could suppress cell growth and cell survival via arresting the cell-cycle in the G2/M phase and inducing apoptosis of neuroblastoma cells.
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Affiliation(s)
- Arumugam Paramasivam
- Department of Genetics, Dr.ALM Post Graduate Institute of Basic Medical Sciences, Sekkizhar Campus, University of Madras, Taramani, India E-mail :
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Huan Z, Luo J, Xu Z, Xie D. Acute Toxicity and Genotoxicity of Carbendazim, Main Impurities and Metabolite to Earthworms (Eisenia foetida). BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 96:62-69. [PMID: 26370277 DOI: 10.1007/s00128-015-1653-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/09/2015] [Indexed: 06/05/2023]
Abstract
The acute toxicity and genotoxicity of carbendazim, two impurities (3-amino-2-hydroxyphenazine and 2,3-diaminophenazine) and one metabolite (2-aminobenzimidazole) to Eisenia foetida were assessed using artificial soil test and comet assay respectively. Acute toxicity results showed carbendazim was moderately toxic to the earthworms with 14 day-LC50 of 8.6 mg/kg dry soil while 3-amino-2-hydroxyphenazine, 2,3-diaminophenazine, and 2-aminobenzimidazole were of low toxicity with 14 day-LC50 values of 19.0, 14.9, and 27.7 mg/kg dry soil respectively (nominal concentration). The olive tail moment and percentage of DNA in the tail were used as genotoxicity indices, and carbendazim could significantly induce DNA damage to the earthworm coelomocytes with obviously positive dose- and duration-response relationships while the other three substances showed similar (p = 0.05) genotoxicity results to the negative controls in all of the tests.
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Affiliation(s)
- Zhibo Huan
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Analysis and Testing Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China.
| | - Jinhui Luo
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Analysis and Testing Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China
| | - Zhi Xu
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Analysis and Testing Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China
| | - Defang Xie
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Analysis and Testing Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China
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Mitigating effect of Indian propolis against mitomycin C induced bone marrow toxicity. Cytotechnology 2015; 68:1789-800. [PMID: 26590833 DOI: 10.1007/s10616-015-9931-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 11/13/2015] [Indexed: 01/09/2023] Open
Abstract
A major drawback with cancer chemotherapy is its severe toxic effects on non-target tissues. Assessment of natural products for their protective effect against anticancer drugs-induced toxicity is gaining importance in cancer biology. The present study was aimed at assessing the protective effect of hydroethanolic extract of Indian propolis (HEIP) against mitomycin C (MMC)-induced genotoxicity and cytotoxicity. Swiss albino mice were injected with various doses of HEIP (100, 200, 300, 400, 600 and 800 mg/kg b. wt., i.p) 1 h prior to MMC (8 mg/kg, i.p.) injection. The geno- and cyto-toxicities were evaluated in mice by performing bone marrow micronucleus and TUNEL assays. In vitro antioxidant and lipid peroxidation inhibitory assays were carried out to understand the mechanism of the protective effects. The significant increase in the frequency of micronculeated cells (12.51 ± 0.48), apoptotic cells (23.43 ± 1.86) and reduction in P/N ratio (0.69 ± 0.04) compared with control indicated the potential geno- and cytotoxic effects of MMC in bone marrow. Pretreatment with HEIP resulted in the significant recovery of the toxic effects induced by MMC. HEIP at 400 mg/kg b. wt. was found to be the optimum dose imparting the maximum protective effects. The in vitro antioxidant and lipid peroxidation inhibitory assays suggest that the extract possesses substantial free radical scavenging activities. In conclusion, HEIP possesses substantial geno- and cyto-protective properties against MMC, which could be mediated through efficient free radical scavenging and inhibitory effect on lipid peroxidation.
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Pagano G, Shyamsunder P, Verma RS, Lyakhovich A. Damaged mitochondria in Fanconi anemia - an isolated event or a general phenomenon? Oncoscience 2014; 1:287-95. [PMID: 25594021 PMCID: PMC4278298 DOI: 10.18632/oncoscience.29] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/20/2014] [Indexed: 12/21/2022] Open
Abstract
Fanconi anemia (FA) is known as an inherited bone marrow failure syndrome associated with cancer predisposition and susceptibility to a number of DNA damaging stimuli, along with a number of clinical features such as upper limb malformations, increased diabetes incidence and typical anomalies in skin pigmentation. The proteins encoded by FA-defective genes (FANC proteins) display well-established roles in DNA damage and repair pathways. Moreover, some independent studies have revealed that mitochondrial dysfunction (MDF) is also involved in FA phenotype. Unconfined to FA, we have shown that other syndromes featuring DNA damage and repair (such as ataxia-telangiectasia, AT, and Werner syndrome, WS) display MDF-related phenotypes, along with oxidative stress (OS) that, altogether, may play major roles in these diseases. Experimental and clinical studies are warranted in the prospect of future therapies to be focused on compounds scavenging reactive oxygen species (ROS) as well as protecting mitochondrial functions.
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Affiliation(s)
- Giovanni Pagano
- Italian National Cancer Institute, G Pascale Foundation, CROM, Mercogliano, AV, Italy
| | - Pavithra Shyamsunder
- Stem Cell and Molecular Biology laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai
| | - Rama S Verma
- Stem Cell and Molecular Biology laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai
| | - Alex Lyakhovich
- Duke-NUS Graduate Medical School, Singapore ; Novosibirsk Institute of Molecular Biology and Biophysics, Russian Federation ; Queen's University Belfast, UK
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15
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Alteration of the redox state with reactive oxygen species for 5-fluorouracil-induced oral mucositis in hamsters. PLoS One 2013; 8:e82834. [PMID: 24376587 PMCID: PMC3869731 DOI: 10.1371/journal.pone.0082834] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 10/29/2013] [Indexed: 01/27/2023] Open
Abstract
Oral mucositis is often induced in patients receiving cancer chemotherapy treatment. It has been reported that oral mucositis can reduce quality of life, as well as increasing the incidence of mortality. The participation of reactive oxygen species (ROS) in the pathogenesis of oral mucositis is well known, but no report has actually demonstrated the presence of ROS. Thus, the purpose of this study was thus to demonstrate the involvement of ROS and the alteration of the redox state in oral mucositis using an in vivo L-band electron spin resonance (ESR) technique. An oral mucositis animal model induced by treatment of 5-fluorouracil with 10% acetic acid in hamster cheek pouch was used. Lipid peroxidation was measured as the level of malondialdehyde determined by the thiobarbituric acid reaction. The rate constants of the signal decay of nitroxyl compounds using in vivo L-band ESR were calculated from the signal decay curves. Firstly, we established the oral mucositis animal model induced by treatment of 5-fluorouracil with acetic acid in hamster cheek pouch. An increased level of lipid peroxidation in oral mucositis was found by measuring malondialdehyde using isolated hamster cheek pouch ulcer. In addition, as a result of in vivo L-band ESR measurements using our model animals, the decay rate constants of carbamoyl-PROXYL, which is a reagent for detecting the redox balance in tissue, were decreased. These results suggest that a redox imbalance might occur by excessive generation of ROS at an early stage of oral mucositis and the consumption of large quantities of antioxidants including glutathione in the locality of oral mucositis. These findings support the presence of ROS involved in the pathogenesis of oral mucositis with anti-cancer therapy, and is useful for the development of novel therapies drugs for oral mucositis.
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16
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Stupak EE, Stupak IV. Cyclic digene system as a control element of a bacterial biosensor. APPL BIOCHEM MICRO+ 2011. [DOI: 10.1134/s0003683812010164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Takagi R, Suzuki Y, Seki Y, Ikehata M, Kajihara C, Shimizu H, Yanagisawa H. Indium Chloride‐induced Micronuclei in In Vivo and In Vitro Experimental Systems. J Occup Health 2011; 53:102-9. [DOI: 10.1539/joh.l9142] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Ryo Takagi
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Yuji Suzuki
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Yoshiko Seki
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Masateru Ikehata
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Chieko Kajihara
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Hidesuke Shimizu
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
| | - Hiroyuki Yanagisawa
- Department of Public Health and Environmental MedicineJikei University School of MedicineJapan
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18
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YQ36: a novel bisindolylmaleimide analogue induces KB/VCR cell death. J Biomed Biotechnol 2010; 2009:535072. [PMID: 20069125 PMCID: PMC2804113 DOI: 10.1155/2009/535072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 05/22/2009] [Accepted: 10/15/2009] [Indexed: 11/17/2022] Open
Abstract
Overexpression of multidrug resistance proteins P-glycoprotein (P-gp, MDR1) causes resistance of the tumor cells against a variety of chemotherapeutic agents. 3-(1-methyl-1H-indol-3-yl)-1-phenyl-4-(1-(3-(piperidin-1-yl)propyl)-1H-pyrazolo[3,4-b]pyridine-3-yl)-1H-pyrrole-2,5-dione (YQ36) is a novel analogue of bisindolylmaleimide, which has been reported to overcome multidrug resistance. Here, we dedicated to investigate the anticancer activity of YQ36 on KB/VCR cells. The results revealed that YQ36 exhibited great antiproliferative activity on three parental cell lines and MDR1 overexpressed cell lines. Moreover, the hypersensitivity of YQ36 was confirmed on the base of great apoptosis induction and unaltered intracellular drug accumulation in KB/VCR cells. Further results suggested that YQ36 could not be considered as a substrate of P-gp, which contributed to its successfully escaping from the efflux mediated by P-gp. Interestingly, we observed that YQ36 could accumulate in nucleus and induce DNA damage. YQ36 could also induce the activation of caspase-3, imposing effects on the mitochondrial function. Collectively, our data demonstrated that YQ36 exhibited potent activities against MDR cells, inducing DNA damage and triggering subsequent apoptosis via mitochondrial pathway.
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Albert BJ, McPherson PA, O'Brien K, Czaicki NL, Destefino V, Osman S, Li M, Day BW, Grabowski PJ, Moore MJ, Vogt A, Koide K. Meayamycin inhibits pre-messenger RNA splicing and exhibits picomolar activity against multidrug-resistant cells. Mol Cancer Ther 2009; 8:2308-18. [PMID: 19671752 DOI: 10.1158/1535-7163.mct-09-0051] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
FR901464 is a potent antitumor natural product that binds to the splicing factor 3b complex and inhibits pre-mRNA splicing. Its analogue, meayamycin, is two orders of magnitude more potent as an antiproliferative agent against human breast cancer MCF-7 cells. Here, we report the picomolar antiproliferative activity of meayamycin against various cancer cell lines and multidrug-resistant cells. Time-dependence studies implied that meayamycin may form a covalent bond with its target protein(s). Meayamycin inhibited pre-mRNA splicing in HEK-293 cells but not alternative splicing in a neuronal system. Meayamycin exhibited specificity toward human lung cancer cells compared with nontumorigenic human lung fibroblasts and retained picomolar growth-inhibitory activity against multidrug-resistant cells. These data suggest that meayamycin is a useful chemical probe to study pre-mRNA splicing in live cells and is a promising lead as an anticancer agent.
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Affiliation(s)
- Brian J Albert
- Departments of 1Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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20
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Begleiter A, El-Gabalawy N, Lange L, Leith MK, Guziec LJ, Guziec FS. A Model for NAD(P)H:Quinoneoxidoreductase 1 (NQO1) Targeted Individualized Cancer Chemotherapy. Drug Target Insights 2009; 4:1-8. [PMID: 21904446 PMCID: PMC3086316 DOI: 10.4137/dti.s1146] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
NQO1 (NAD(P)H:quinoneoxidoreductase 1) is a reductive enzyme that is an important activator of bioreductive antitumor agents. NQO1 activity varies in individual tumors but is generally higher in tumor cells than in normal cells. NQO1 has been used as a target for tumor specific drug development. We investigated a series of bioreductive benzoquinone mustard analogs as a model for NQO1 targeted individualized cancer chemotherapy. We compared the tumor cell growth inhibitory activity of benzoquinone mustard analogs with sterically bulky groups of different size and placed at different positions on the benzoquinone ring, using tumor cell lines with different levels of NQO1. We demonstrated that functional groups of different steric size could be used to produce a series of bioreductive antitumor agents that were activated by different levels of NQO1 in tumor cells. This series of drugs could then be used to target cells with specific levels of NQO1 for growth inhibition and to avoid damage to normal cells, like bone marrow cells, that have low levels of NQO1. This approach could be used to develop new bioreductive antitumor agents for NQO1 targeted individualized cancer chemotherapy.
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Affiliation(s)
- Asher Begleiter
- Manitoba Institute of Cell Biology, CancerCare Manitoba, Departments of Internal Medicine and Pharmacology and Therapeutics, University of Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 Canada
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21
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Niikawa M, Nagase H. Effect of aspirin on DNA damage induced by MMC in Drosophila. Pharmacotherapy 2007; 61:250-3. [PMID: 17336029 DOI: 10.1016/j.biopha.2007.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 01/10/2007] [Indexed: 11/20/2022]
Abstract
In our previous paper, we found that aspirin suppressed the genotoxicity of mitomycin C (MMC) in a somatic mutation and recombination test (SMART) in Drosophila melanogaster. In order to reveal the mechanism of antigenotoxicity of aspirin, we evaluated the protective effects of aspirin against the genotoxicity of MMC with the DNA repair test in Drosophila melanogaster. Three types of treatment of aspirin were performed as co-, post- and pre-treatment. Aspirin co-treatment suppressed effectively the genotoxicity of MMC in a dose-dependent manner and the sex ratio at a dose of aspirin 10mg/bottle elevated from 0.01 (without aspirin) to 0.65 at sc z(1) w(+(TE)) mei-9(a) mei-41(D5)/-C(1)DX, y f [mei-9 mei-41, Rec(-) male.Rec(+) female] consists of DNA repair-deficient (Rec(-)) males and -proficient (Rec(+)) females. The antigenotoxic effect of aspirin on [mei-41, Rec(-) male.Rec(+) female] was similar to that on [mei-9, Rec(-) male.Rec(+) female]. But post- and pre-treatment by aspirin did not affect the genotoxicity of MMC on [mei-9 mei-41, Rec(-) male.Rec(+) female].
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Affiliation(s)
- Miki Niikawa
- Department of Hygienics, Gifu Pharmaceutical University, 5-6-1 Mitahora-higashi, Gifu 502-8585, Japan.
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22
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Mascarenhas J, Sanchez H, Tadesse S, Kidane D, Krisnamurthy M, Alonso JC, Graumann PL. Bacillus subtilis SbcC protein plays an important role in DNA inter-strand cross-link repair. BMC Mol Biol 2006; 7:20. [PMID: 16780573 PMCID: PMC1533848 DOI: 10.1186/1471-2199-7-20] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2006] [Accepted: 06/16/2006] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Several distinct pathways for the repair of damaged DNA exist in all cells. DNA modifications are repaired by base excision or nucleotide excision repair, while DNA double strand breaks (DSBs) can be repaired through direct joining of broken ends (non homologous end joining, NHEJ) or through recombination with the non broken sister chromosome (homologous recombination, HR). Rad50 protein plays an important role in repair of DNA damage in eukaryotic cells, and forms a complex with the Mre11 nuclease. The prokaryotic ortholog of Rad50, SbcC, also forms a complex with a nuclease, SbcD, in Escherichia coli, and has been implicated in the removal of hairpin structures that can arise during DNA replication. Ku protein is a component of the NHEJ pathway in pro- and eukaryotic cells. RESULTS A deletion of the sbcC gene rendered Bacillus subtilis cells sensitive to DNA damage caused by Mitomycin C (MMC) or by gamma irradiation. The deletion of the sbcC gene in a recN mutant background increased the sensitivity of the single recN mutant strain. SbcC was also non-epistatic with AddAB (analog of Escherichia coli RecBCD), but epistatic with RecA. A deletion of the ykoV gene encoding the B. subtilis Ku protein in a sbcC mutant strain did not resulted in an increase in sensitivity towards MMC and gamma irradiation, but exacerbated the phenotype of a recN or a recA mutant strain. In exponentially growing cells, SbcC-GFP was present throughout the cells, or as a central focus in rare cases. Upon induction of DNA damage, SbcC formed 1, rarely 2, foci on the nucleoids. Different to RecN protein, which forms repair centers at any location on the nucleoids, SbcC foci mostly co-localized with the DNA polymerase complex. In contrast to this, AddA-GFP or AddB-GFP did not form detectable foci upon addition of MMC. CONCLUSION Our experiments show that SbcC plays an important role in the repair of DNA inter-strand cross-links (induced by MMC), most likely through HR, and suggest that NHEJ via Ku serves as a backup DNA repair system. The cell biological experiments show that SbcC functions in close proximity to the replication machinery, suggesting that SbcC may act on stalled or collapsed replication forks. Our results show that different patterns of localization exist for DNA repair proteins, and that the B. subtilis SMC proteins RecN and SbcC play distinct roles in the repair of DNA damage.
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Affiliation(s)
- Judita Mascarenhas
- Institut für Mikrobiologie, Albert-Ludwigs Universität Freiburg, Stefan Meier Str. 19, 79104 Freiburg, Germany
- Institut für Klinische Zytobiologie und Zytopathologie, Robert-Koch-Straße 6, 35037 Marburg, Germany
| | - Humberto Sanchez
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, C/Darwin 3, Campus Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Serkalem Tadesse
- Institut für Mikrobiologie, Albert-Ludwigs Universität Freiburg, Stefan Meier Str. 19, 79104 Freiburg, Germany
| | - Dawit Kidane
- Institut für Mikrobiologie, Albert-Ludwigs Universität Freiburg, Stefan Meier Str. 19, 79104 Freiburg, Germany
| | - Mahalakshmi Krisnamurthy
- Institut für Mikrobiologie, Albert-Ludwigs Universität Freiburg, Stefan Meier Str. 19, 79104 Freiburg, Germany
| | - Juan C Alonso
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, C/Darwin 3, Campus Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Peter L Graumann
- Institut für Mikrobiologie, Albert-Ludwigs Universität Freiburg, Stefan Meier Str. 19, 79104 Freiburg, Germany
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Digby T, Leith MK, Thliveris JA, Begleiter A. Effect of NQO1 induction on the antitumor activity of RH1 in human tumors in vitro and in vivo. Cancer Chemother Pharmacol 2005; 56:307-16. [PMID: 15877230 DOI: 10.1007/s00280-004-0961-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Accepted: 10/18/2004] [Indexed: 01/06/2023]
Abstract
NQO1 is a reductive enzyme that is important for the activation of many bioreductive agents and is a target for an enzyme-directed approach to cancer therapy. It can be selectively induced in many tumor types by a number of compounds including dimethyl fumarate and sulforaphane. Mitomycin C is a bioreductive agent that is used clinically for treatment of solid tumors. RH1 (2,5-diaziridinyl-3-(hydroxymethyl)- 6-methyl-1,4-benzoquinone) is a new bioreductive agent currently in clinical trials. We have shown previously that induction of NQO1 can enhance the antitumor activity of mitomycin C in tumor cells in vitro and in vivo. As RH1 is activated selectively by NQO1 while mitomycin C is activated by many reductive enzymes, we investigated whether induction of NQO1 would produce a greater enhancement of the antitumor activity of RH1 compared with mitomycin C. HCT116 human colon cancer cells and T47D human breast cancer cells were incubated with or without dimethyl fumarate or sulforaphane followed by mitomycin C or RH1 treatment, and cytotoxic activity was measured by a clonogenic (HCT116) or MTT assay (T47D). Dimethyl fumarate and sulforaphane treatment increased NQO1 activity by 1.4- to 2.8-fold and resulted in a significant enhancement of the antitumor activity of mitomycin C, but not of RH1. This appeared to be due to the presence of a sufficient constitutive level of NQO1 activity in the tumor cells to fully activate the RH1. Mice were implanted with HL60 human promyelocytic leukemia cells, which have low levels of NQO1 activity. The mice were fed control or dimethyl fumarate-containing diet and were treated with RH1. NQO1 activity in the tumors increased but RH1 produced no antitumor activity in mice fed control or dimethyl fumarate diet. This is consistent with a narrow window of NQO1 activity between no RH1 activation and maximum RH1 activation. This study suggests that selective induction of NQO1 in tumor cells is not likely to be an effective strategy for enhancing the antitumor activity of RH1. In addition, we found that RH1 treatment produced significant leukopenia in mice that may be of concern in the clinic. These results suggest that the ease of reduction of RH1 by NQO1 makes it a poor candidate for an enzyme-directed approach to cancer therapy.
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Affiliation(s)
- Tyler Digby
- Manitoba Institute of Cell Biology, CancerCare Manitoba, University of Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba, R3E 0V9, Canada
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Begleiter A, Leith MK, Thliveris JA, Digby T. Dietary induction of NQO1 increases the antitumour activity of mitomycin C in human colon tumours in vivo. Br J Cancer 2004; 91:1624-31. [PMID: 15467770 PMCID: PMC2409939 DOI: 10.1038/sj.bjc.6602171] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The bioreductive antitumour agent, mitomycin C (MMC), requires activation by reductive enzymes like NAD(P)H:quinone oxidoreductase 1 (NQO1). We used a novel approach to increase MMC efficacy by selectively inducing NQO1 in tumour cells in vivo. CD-1 nude mice were implanted with HCT116 cells, and fed control diet or diet containing 0.3% of the NQO1 inducer, dimethyl fumarate (DMF). The mice were then treated with saline, 2.0, 3.5 or 2.0 mg kg−1 MMC and dicoumarol, an NQO1 inhibitor. The DMF diet increased NQO1 activity by 2.5-fold in the tumours, but had no effect in marrow cells. Mice given control diet/2.0 mg kg−1 MMC had tumours with the same volume as control mice; however, mice given DMF diet/2.0 mg kg−1 MMC had significantly smaller tumours. Tumour volumes in mice given DMF/2.0 mg kg−1 MMC were similar to those in mice given control diet/3.5 mg kg−1 MMC. Tumour inhibition was partially reversed in mice given DMF/2.0 mg kg−1 MMC and dicoumarol. DMF diet/2.0 mg kg−1 MMC treatment did not increase myelosuppression and did not produce any organ toxicity. These results provide strong evidence that dietary inducers of NQO1 can increase the antitumour activity of bioreductive agents like MMC without increasing toxicity.
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Affiliation(s)
- A Begleiter
- Department of Internal Medicine, Manitoba Institute of Cell Biology, CancerCare Manitoba, University of Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba, Canada R3E 0V9.
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25
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Hong Y, Müller UR, Lai F. Discriminating two classes of toxicants through expression analysis of HepG2 cells with DNA arrays. Toxicol In Vitro 2003; 17:85-92. [PMID: 12537966 DOI: 10.1016/s0887-2333(02)00122-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Microarray technology provides a rapid and cost-effective method to associate specific cellular responses with unique gene expression patterns. If characteristic expression patterns of a small number of genes could be associated with drug toxicity, this association may be used for toxicity prediction, and thereby to reduce the need for traditional toxicity testing. To test this hypothesis, we have designed an array composed of 92 known human genes of toxicological interest (including seven housekeeping genes) and eight bacterial controls. HepG2 cells were treated with either ethanol or one of two quinone containing anticancer drugs, mitomycin C or doxorubicin. RNA was isolated from treated and untreated cells, differentially labeled with fluorescent dyes, and then hybridized to the array. Our results show that the expression patterns induced by ethanol and the anticancer drugs are different. Both of the anticancer drugs, but not ethanol had a differential effect on the regulation of several genes, including CYP4F2/3, CYP3A3, TNFRSF6 and CHES1, demonstrating that the two drugs might function through a similar mechanism, which differs from that of ethanol. These results suggest that microarray-based expression analysis may offer a rapid and efficient means for assessing drug toxicity.
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Affiliation(s)
- Y Hong
- Science and Technology Division, Corning Incorporated, Corning, NY 14831, USA
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26
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Abstract
A number of xenobiotics require redox reactions to form the reactive intermediates involved in the ultimate toxic events (e.g., adduct formation). The same mechanisms lead to the formation of reactive oxygen species (ROS), which can themselves exert direct toxicity including, e.g., DNA oxidative damage or glutathione depletion. The occurence of both mechanistic features in xenobiotic activation and toxicity may raise some difficulties in ascertaining the respective roles of reactive intermediates versus ROS-related mechnisms. An example is provided by the toxicity mechanisms of mitomycin C (MMC) and diepoxybutane (DEB), which are commonly referred to as 'cross-linkers'. Their toxic actions, however, are well-known to be modulated via redox parameters, such as oxygen tension, antioxidants levels, or thioredoxin overexpression. The diagnostic assessment of Fanconi's anaemia (FA) relies on MMC and DEB sensitivity, which is usually referred to as 'cross-linker sensitivity'; thus the redox-dependent toxicities of MMC and DEB may have direct implications for the definition of FA phenotype. Another major aspect in ROS formation relies on the extensive evidence pointing to the requirement for oxidative, as well as nitrosative activities in triggering a number of key events in cell division and differentiation, and in early embryogenesis. In turn, antioxidants that may prevent ROS-associated cellular damage in adult cells may prove to exert adverse or fatal outcomes when administered in early life stages. The overall information available on xenobiotic redox biotransformation and on the physiopathological roles of ROS points to the need of addressing ad hoc studies that should take into account the multiplicity of mechanistic events involved.
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Affiliation(s)
- G Pagano
- Italian National Cancer Institute, G Pascale Foundation, Naples, Italy.
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27
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Pagano G, Degan P, De Biase A, Iaccarino M, Warnau M. Diepoxybutane and mitomycin C toxicity is associated with the induction of oxidative DNA damage in sea urchin embryos. Hum Exp Toxicol 2001; 20:651-5. [PMID: 11936580 DOI: 10.1191/096032701718890577] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Diepoxybutane (DEB)- and mitomycin C (MMC)-associated toxicity was investigated in embryos from the sea urchin (SU) species Sphaerechinus granularis. DEB- and MMC-induced toxicity resulted in S. granularis embryos and larvae at concentrations ranging 10(-5) to 10(-4) M DEB, and 3 x 10(-6) to 3 x 10(-5) M MMC, in terms of larval malformations, developmental arrest and mortality. The formation of DNA oxidative damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured in DEB- and in MMC-exposed embryos (at gastrula stage). A dose-dependent increase in 8-OHdG levels was observed that was significantly correlated with DEB- and MMC-induced developmental defects. The results lend further support to the body of evidence associating both DEB and MMC toxicity with oxidative stress, including DNA oxidative damage.
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Affiliation(s)
- G Pagano
- G. Pascale Foundation, Italian National Cancer Institute, Naples
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Kelley MR, Tritt R, Xu Y, New S, Freie B, Clapp DW, Deutsch WA. The Drosophila S3 multifunctional DNA repair/ribosomal protein protects Fanconi anemia cells against oxidative DNA damaging agents. Mutat Res 2001; 485:107-19. [PMID: 11182542 DOI: 10.1016/s0921-8777(00)00067-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cells harvested from Fanconi anemia (FA) patients show an increased hypersensitivity to the multifunctional DNA damaging agent mitomycin C (MMC), which causes cross-links in DNA as well as 7,8-dihydro-8-oxoguanine (8-oxoG) adducts indicative of escalated oxidative DNA damage. We show here that the Drosophila multifunctional S3 cDNA, which encodes an N-glycosylase/apurinic/apyrimidinic (AP) lyase activity was found to correct the FA Group A (FA(A)) and FA Group C (FA(C)) sensitivity to MMC and hydrogen peroxide (H2O2). Furthermore, the Drosophila S3 cDNA was shown to protect AP endonuclease deficient E. coli cells against H(2)O(2) and MMC, and also protect 8-oxoG repair deficient mutM E. coli strains against MMC and H2O2 cell toxicity. Conversely, the human S3 protein failed to complement the AP endonuclease deficient E. coli strain, most likely because it lacks N-glycosylase activity for the repair of oxidatively-damaged DNA bases. Although the human S3 gene is clearly not the genetic alteration in FA cells, our results suggest that oxidative DNA damage is intimately involved in the overall FA phenotype, and the cytotoxic effect of selective DNA damaging agents in FA cells can be overcome by trans-complementation with specific DNA repair cDNAs. Based on these findings, we would predict other oxidative repair proteins, or oxidative scavengers, could serve as protective agents against the oxidative DNA damage that occurs in FA.
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Affiliation(s)
- M R Kelley
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, 702 Barnhill Dr., Room 2600, Indianapolis, IN 46202, USA.
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Urano M, Kuroda M, Nishimura Y. For the clinical application of thermochemotherapy given at mild temperatures. Int J Hyperthermia 1999; 15:79-107. [PMID: 10323618 DOI: 10.1080/026567399285765] [Citation(s) in RCA: 231] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
Abstract
It has been demonstrated in vitro and in vivo that hyperthermia can enhance the cytotoxicity of some chemotherapeutic agents. This paper summarizes the authors' own laboratory studies on the effect of chemotherapeutic agents given at elevated temperatures, experimental results obtained using animal tumour systems in other laboratories, and clinical trials of thermochemotherapy reported in literature. The in vivo studies have demonstrated that the thermal enhancement of cytotoxicity of many chemotherapeutic agents is maximized at mild temperatures such as at 40.5-43 degrees C. Comparison of in vitro and in vivo results using five agents show that the in vivo thermal enhancement increases with an increase in the activation energy obtained in the temperature range between 40.5 and 43.0 degrees C. A summary of experimental results obtained by various investigators indicates a potentially wide variation in the thermal enhancement of a given agent among the different types of tumours and suggests potential agents useful at moderately elevated temperatures. In vivo studies on nine different agents indicate that the drug(s) of choice at physiological temperatures may not be the drug(s) of choice at elevated temperatures. It is also shown that drug concentration in the target must be high for sufficient thermal enhancement. Clinical trials of thermochemotherapy have employed various heating methods, including local heating, hyerthermic perfusion and whole body hyperthermia. Extensive trials have been made in the treatment of melanoma and soft tissue sarcoma in the extremity. Hyperthermic isolated perfusion with chemotherapeutic(s) provides much higher drug concentration than a systemic drug administration in the target(s), resulting in a high tumour response rate and an increased survival of the patients. It is of interest that the most successful agent used in the treatment of both melanomas and sarcomas is melphalan and is the drug of choice at moderately elevated temperatures among the nine agents tested in the in vivo studies. Current results using the tumour necrosis factor with melphalan are impressive. In several institutes, techniques have been developed to uniformly heat the localized tumour, but studies are needed to find an agent effective at elevated temperatures to each type of tumours and to establish the methods for obtaining a sufficient drug concentration in the target tissue.
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Affiliation(s)
- M Urano
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
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Beard SE, Capaldi SR, Gee P. Stress responses to DNA damaging agents in the human colon carcinoma cell line, RKO. Mutat Res 1996; 371:1-13. [PMID: 8950345 DOI: 10.1016/s0165-1218(96)90089-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
DNA damage results from a wide variety of external agents such as chemicals and radiation. The consequences of exposure to agents that damage DNA have been traditionally studied from the perspective of cell survival and mutagenesis. Mutations are late endpoints of DNA damage. Cells respond to the earlier stages of DNA damage by inducing the expression of several genes, including those specific of the nature of the lesion. These early transcriptional responses are likely to predetermine the later fate of the damaged cell. Genes activated during this early response include those involved in DNA repair, replication, and growth control. We are interested in the transcriptional mechanisms by which cells respond to DNA damaging agents. To facilitate the measurement of gene induction, we used seven different reporter constructs integrated stably into the RKO cell line derived from a human colon carcinoma. These constructs were derived from promoters and/or response elements isolated from genes associated with DNA damage responses in human cells, and were fused to the bacterial reporter gene, choramphenicol acetyl transferase (CAT). The cell lines generated in this manner contain the promoters and/or response elements representing DNA polymerase beta, p53, gadd (growth arrest and DNA damage) 45 and 153, c-fos, TPA response element, and tissue-type plasminogen activator. These recombinant cell lines were assembled in a 96-well microtiter plate permitting their simultaneous exposure to compounds and subsequent CAT protein measurement. This assembly has been designated the CAT-Tox (D) assay. These cell lines were exposed to different classes of DNA damaging agents including those which covalently join bases to form dimers (e.g., UVC irradiation), generate DNA adducts by alkylation (e.g., methylmethane sulfonate [MMS], ethylmethane sulfonate [EMS], N-methyl-N-nitro-N-nitrosoguanine [MNNG], dimethylnitrosamine [DMN]), cross-link DNA (e.g., mitomycin C), and inhibit DNA replication by intercalative (e.g., actinomycin D) and nonintercalative (e.g., hydroxyurea) mechanisms. The transcriptional responses were measured as a function of the accumulation of CAT protein using antibodies against CAT protein in a standard ELISA. Endogenous cellular responses were evaluated for a number of the genes represented in the assay at both the mRNA and protein levels by Northern and Western blot analysis, respectively. These data corroborate the stress-induced responses measured by CAT ELISA in the CAT-Tox (D) assay, demonstrating the usefulness of this assay as a rapid and sensitive method for detection of DNA damaging agents in human cells.
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Affiliation(s)
- S E Beard
- Xenometrix Inc., Boulder, CO 80301, USA.
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31
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Benvenuto JA, Hittelman WN, Zwelling LA, Plunkett W, Pandita TK, Farquhar D, Newman RA. Biochemical pharmacology of penclomedine (NSC-338720). Biochem Pharmacol 1995; 50:1157-64. [PMID: 7488229 DOI: 10.1016/0006-2952(95)00251-t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Penclomedine (PEN) is a synthetic pyridine derivative that has been selected for clinical development based on its activity against human and mouse breast tumors implanted in mice. Its mechanism of action was unclear, and we were interested in determining its mechanism of cytotoxicity in vitro and in vivo. We found chromosome breaks, gaps, and exchanges in P388 ascites cells from BD2F1 mice treated with 200 mg/kg PEN. Maximal observed damage occurred 24 hr after drug administration. Alkaline elution indicated only limited DNA strand breaks and interstrand cross-linking. In vitro, PEN (75 micrograms/mL) inhibited RNA and DNA syntheses almost completely. In addition, incubation of [14C]PEN with rat liver S-9 fraction in the presence of calf thymus DNA resulted in the stable transfer of radioactivity to DNA. Addition of butylated hydroxytoluene, a free radical scavenger, to the incubation mixture inhibited the binding of drug to DNA, implicating free radicals as the ultimate reactive species. These data suggest that PEN can be metabolized to free radical, DNA-reactive products, and that its cytotoxicity is due to chromosomal damage produced by monofunctional alkylation. As an alternate mechanism, the ability of PEN to inhibit cellular dihydroorotate dehydrogenase was explored. Although PEN is an inhibitor of this enzyme in cells in vivo, in vitro, and in isolated cell sonicates, HPLC analyses of ribonucleotide triphosphate pools in P388 cells showed that all triphosphates had increased, especially UTP. Addition of uridine to the cell culture failed to prevent PEN-mediated cytotoxicity, suggesting that inhibition of de novo pyrimidine biosynthesis was not likely to be an important mechanism of action of this drug. These data suggest that PEN is activated in cells to a free radical that binds DNA.
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Affiliation(s)
- J A Benvenuto
- Department of Clinical Investigation, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA
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Srikanth NS, Mudipalli A, Maccubbin AE, Gurtoo HL. Mutations in a shuttle vector exposed to activated mitomycin C. Mol Carcinog 1994; 10:23-9. [PMID: 8185826 DOI: 10.1002/mc.2940100105] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The cytotoxicity of the potent antibiotic and antitumor agent mitomycin C (MMC) is due to its irreversible binding to DNA. Alkylating species generated by bioreductive activation of MMC are known to cause monoadducts and cross-links in DNA by specifically binding to guanine residues. To gain insight into how these lesions lead to base- and sequence-specific mutations, shuttle vector pSP189 was treated with MMC chemically reduced by treatment with sodium borohydride, replicated in human Ad293 cells, rescued in bacteria, and analyzed for mutations in the supF tRNA gene sequence. The MMC-induced mutations were predominantly base substitutions. Eighty-four percent of the base substitutions were transversions, with G:C-->T:A the major transversion. Single base deletions were the other major mutational event, and 77% of these were G:C deletions. Base positions 115, 123, and 163 were mutational hot spots based on the frequency of independent mutations. Identification of a single MMC adduct (presumed to be a modified G on the basis of its Rf value) and clustering of MMC-induced mutations at three GC-rich areas (nt 100-123, 152-163, and 168-176) suggested that the mutational spectrum we found was due to binding of MMC to guanine on either strand of the plasmid DNA.
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Affiliation(s)
- N S Srikanth
- Department of Experimental Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263
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Plumb JA, Workman P. Unusually marked hypoxic sensitization to indoloquinone EO9 and mitomycin C in a human colon-tumour cell line that lacks DT-diaphorase activity. Int J Cancer 1994; 56:134-9. [PMID: 8262670 DOI: 10.1002/ijc.2910560124] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Studies with purified DT-diaphorase have shown that the enzyme is capable of catalyzing a two-electron reduction of the novel indoloquinone EO9 to a DNA-damaging alkylating species. The aim of this study was to determine to what extent DT-diaphorase may be involved in the metabolic activation of EO9 and mitomycin C in both aerobic and hypoxic conditions. Two human colon-carcinoma cell lines were used; HT29 has high levels of DT-diaphorase whilst BE lacks this activity because of a point mutation in the NQOI gene. In aerobic conditions the 2 cell lines show similar sensitivities to a number of cytotoxic drugs including cisplatin, doxorubicin and etoposide. They are equally sensitive to the benzotriazine di-N-oxide SR 4233 but HT29 is more sensitive than BE to mitomycin C and EO9. Sensitivity to SR 4233 is increased by about 100-fold for both cell lines in hypoxic conditions. DT-diaphorase-deficient BE cells show markedly increased sensitivity to mitomycin C and particularly EO9 in hypoxic conditions, whereas DT-diaphorase-rich HT29 cells show little hypoxic sensitization to these agents unless exposed in the presence of dicoumarol. These results suggest that DT-diaphorase can reduce EO9 and mitomycin C to potent cytotoxic species in aerobic conditions, and this activity predominates over the one-electron-reducing enzymes even in hypoxic conditions. In the absence of DT-diaphorase activity, EO9 and mitomycin C are reduced in hypoxic conditions, presumably by one-electron-reducing enzymes, to a similar or greater extent than is achieved with DT-diaphorase.
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Affiliation(s)
- J A Plumb
- CRC Department of Medical Oncology, University of Glasgow, Bearsden, UK
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Van den Berg DJ, Francke U. Sensitivity of Roberts syndrome cells to gamma radiation, mitomycin C, and protein synthesis inhibitors. SOMATIC CELL AND MOLECULAR GENETICS 1993; 19:377-92. [PMID: 8211379 DOI: 10.1007/bf01232749] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Roberts syndrome (RS) is a rare autosomal recessive disorder characterized by pre- and postnatal growth retardation, limb reduction abnormalities, and craniofacial anomalies. Mitotic chromosomes from RS individuals display repulsion of heterochromatin regions or centromere splitting, leading to a railroad-track appearance of mitotic chromosomes. Abnormalities in metaphase duration, anaphase progression, nuclear morphology, and increased frequency of micronucleation have been reported in RS cells. Cells from RS heterozygotes are normal in these respects, and in vitro complementation of the defects in somatic cell hybrids has been reported. Therefore, in preparation for the isolation of cDNAs that complement the RS defect, we investigated various drug treatments to identify an agent that specifically involves the growth of RS cells. Based on the cytogenetic and cell biologic findings, we chose agents that increase micronucleation or inhibit protein synthesis. We found that RS cells are hypersensitive to gamma radiation, mitomycin C, G418 and hygromycin B, but not to colcemid or streptonigrin when compared to normal cells. DNA content and cell viability analysis confirmed that the sensitivity to gamma irradiation was primarily due to increased cell death.
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Affiliation(s)
- D J Van den Berg
- Department of Genetics, Stanford University School of Medicine, California 94305
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Nishiyama M, Saeki S, Aogi K, Hirabayashi N, Toge T. Relevance of DT-diaphorase activity to mitomycin C (MMC) efficacy on human cancer cells: differences in in vitro and in vivo systems. Int J Cancer 1993; 53:1013-6. [PMID: 8473041 DOI: 10.1002/ijc.2910530626] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Using 4 human cancer cell lines, 4 tumors xenografted into nude mice, and 11 fresh tumor specimens removed at surgery, we investigated the relevance of NAD(P)H:quinone oxidoreductase (DT-diaphorase, DTD) activity (nmoles/min/mg protein) to mitomycin C (MMC)-induced cytotoxicity. In culture cell lines, KB cells had significantly higher levels of DTD activity (8260) than PH101 (1934), SH101 (1805) or K562 (1796), and the highest sensitivity to MMC. In contrast, the higher the DTD activity of xenografts, the greater their resistance to MMC, while the inhibition rate of relative tumor growth for MMC, as evaluated by the NCI protocol, was highest in SH-6, high in CH-5, lower in CH-4 and lowest in EH-6. The investigation using 11 fresh tumor specimens also showed an inverse relationship between IC50 values after a 30-min MMC treatment, as evaluated by ATP assay and DTD activities. Moreover, a non-toxic DTD inhibitor, dicoumarol (DIC), or flavin adenine dinucleotide (FAD), suppressed the efficacy of MMC in culture cells, but enhanced it in xenografts. Thus, we suggest that DTD may play an important role in MMC-induced cytotoxicity but MMC metabolism by DTD in solid tumors may differ from that in culture cells.
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Affiliation(s)
- M Nishiyama
- Department of Surgery, Hiroshima University, Japan
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36
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Barber CV, Fantel AG. The role of oxygenation in embryotoxic mechanisms of three bioreducible agents. TERATOLOGY 1993; 47:209-23. [PMID: 8475464 DOI: 10.1002/tera.1420470305] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Many xenobiotics used in the treatment of hypoxic pathogens and tumors require reductive bioactivation under anaerobic conditions for maximal effectiveness and/or toxicity. A number of agents of this type have been shown to be teratogenic in vitro and/or in vivo. Early conceptuses may be vulnerable to these agents because they exist in a relatively anaerobic environment and have the capacity to perform reductive metabolism. It has been hypothesized that the single electron redox potential of bioreducible agents plays a dominant role in the capacity to induce anomalies. We examined the in vitro embryotoxicity in rats of three bioreducible drugs of similar redox potential under normoxic and hypoxic conditions as well as the capacity of those drugs to redox cycle and to damage DNA in embryonic tissue. Adriamycin, mitomycin C, and niridazole were shown to have differential embryotoxic responses in vitro to altered oxygenation. Studies of the bases of drug action showed (1) Adriamycin induces DNA strand breaks at concentrations that correlate well with embryolethality; (2) Mitomycin C does not induce strand breaks, but its dysmorphogenicity is increased by hypoxia; and (3) Niridazole does not produce DNA damage but appears to induce asymmetric malformations by depleting embryonic oxygen through redox cycling. Together the studies show that dysmorphogenic and embryolethal effects may result from separate mechanisms and that oxygenation plays an important role in those mechanisms.
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Affiliation(s)
- C V Barber
- Department of Pediatrics, University of Washington, Seattle 98195
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37
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Sinha BK, Mimnaugh EG. Free radicals and anticancer drug resistance: oxygen free radicals in the mechanisms of drug cytotoxicity and resistance by certain tumors. Free Radic Biol Med 1990; 8:567-81. [PMID: 2113883 DOI: 10.1016/0891-5849(90)90155-c] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Certain anticancer agents form free radical intermediates during enzymatic activation. Recent studies have indicated that free radicals generated from adriamycin and mitomycin C may play a critical role in their toxicity to human tumor cells. Furthermore, it is becoming increasingly apparent that reduced drug activation and or enhanced detoxification of reactive oxygen species may be related to the resistance to these anticancer agents by certain tumor cell lines. The purposes of this review are to summarize the evidence pointing toward the significance of free radicals formation in drug toxicity and to evaluate the role of decreased free radical formation and enhanced free radical scavenging and detoxification in the development of anticancer drug resistance by a spectrum of tumor cell types. Studies failing to support the participation of oxyradicals in the cytotoxicity and resistance of adriamycin are also discussed.
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Affiliation(s)
- B K Sinha
- Medicine Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Abstract
This review examines the formation of free radical intermediates from a number of clinically active antitumor agents including quinone-containing antibiotics and etoposide. An attempt is also made to relate the formation of these reactive intermediates to biochemical and pharmacological basis for tumor cell kill and resistance. The formation of these intermediates in some tumor cells has been detected by both direct ESR and spin-trapping technique. The detection of free radicals in biological systems, however, depends upon cellular bioenvironments, e.g. reducing conditions, and the presence and/or absence of activation and detoxification mechanisms. Evidence shows that certain antitumor drugs generate free radicals in vitro and in vivo and that these reactive species kill tumor cells by causing damage to DNA, membranes or enzymes.
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Affiliation(s)
- B K Sinha
- Clinical Pharmacology Branch, National Cancer Institute, Bethesda, MD 20892
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