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Karagiannis TC, Wall M, Ververis K, Pitsillou E, Tortorella SM, Wood PA, Rafehi H, Khurana I, Maxwell SS, Hung A, Vongsvivut J, El-Osta A. Characterization of K562 cells: uncovering novel chromosomes, assessing transferrin receptor expression, and probing pharmacological therapies. Cell Mol Life Sci 2023; 80:248. [PMID: 37578596 PMCID: PMC11072675 DOI: 10.1007/s00018-023-04905-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 07/30/2023] [Accepted: 07/31/2023] [Indexed: 08/15/2023]
Abstract
Human erythroleukemic K562 cells represent the prototypical cell culture model of chronic myeloid leukemia (CML). The cells are pseudo-triploid and positive for the Philadelphia chromosome. Therefore, K562 cells have been widely used for investigating the BCR/ABL1 oncogene and the tyrosine kinase inhibitor, imatinib-mesylate. Further, K562 cells overexpress transferrin receptors (TfR) and have been used as a model for targeting cytotoxic therapies, via receptor-mediated endocytosis. Here, we have characterized K562 cells focusing on the karyotype of cells in prolonged culture, regulation of expression of TfR in wildtype (WT) and doxorubicin-resistant cells, and responses to histone deacetylase inhibition (HDACi). Karyotype analysis indicates novel chromosomes and gene expression analysis suggests a shift of cultured K562 cells away from patient-derived leukemic cells. We confirm the high expression of TfR on K562 cells using immunofluorescence and cell-surface receptor binding radioassays. Importantly, high TfR expression is observed in patient-derived cells, and we highlight the persistent expression of TfR following doxorubicin acquired resistance. Epigenetic analysis indicates that permissive histone acetylation and methylation at the promoter region regulates the transcription of TfR in K562 cells. Finally, we show relatively high expression of HDAC enzymes in K562 cells and demonstrate the chemotoxic effects of HDACi, using the FDA-approved hydroxamic acid, vorinostat. Together with a description of morphology, infrared spectral analysis, and examination of metabolic properties, we provide a comprehensive characterization of K562 cells. Overall, K562 cell culture systems remain widely used for the investigation of novel therapeutics for CML, which is particularly important in cases of imatinib-mesylate resistance.
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MESH Headings
- Humans
- Imatinib Mesylate/pharmacology
- Imatinib Mesylate/therapeutic use
- K562 Cells
- Fusion Proteins, bcr-abl/genetics
- Transferrin
- Pyrimidines/pharmacology
- Drug Resistance, Neoplasm/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Histone Deacetylases/metabolism
- Doxorubicin/pharmacology
- Doxorubicin/therapeutic use
- Receptors, Transferrin/genetics
- Chromosomes/metabolism
- Mesylates/pharmacology
- Apoptosis
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Affiliation(s)
- Tom C Karagiannis
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC, 3004, Australia.
- Epigenomic Medicine Laboratory at prospED Training, Carlton, VIC, 3053, Australia.
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, 3010, Australia.
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, 3010, Australia.
- Epigenomic in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC, 3004, Australia.
| | - Meaghan Wall
- Victorian Cancer Cytogenetics Service, St Vincent's Hospital, Fitzroy, VIC, 3065, Australia
- Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, VIC, 3065, Australia
| | - Katherine Ververis
- Epigenomic Medicine Laboratory at prospED Training, Carlton, VIC, 3053, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Eleni Pitsillou
- Epigenomic Medicine Laboratory at prospED Training, Carlton, VIC, 3053, Australia
- School of Science, STEM College, RMIT University, VIC, 3001, Australia
| | - Stephanie M Tortorella
- Epigenomic Medicine Laboratory at prospED Training, Carlton, VIC, 3053, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Peter A Wood
- Epigenomic Medicine Laboratory at prospED Training, Carlton, VIC, 3053, Australia
| | - Haloom Rafehi
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
| | - Ishant Khurana
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC, 3004, Australia
| | - Scott S Maxwell
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC, 3004, Australia
| | - Andrew Hung
- School of Science, STEM College, RMIT University, VIC, 3001, Australia
| | | | - Assam El-Osta
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC, 3004, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Sha Tin, Hong Kong SAR, China
- Hong Kong Institute of Diabetes and Obesity, Prince of Wales Hospital, The Chinese University of Hong Kong, 3/F Lui Che Woo Clinical Sciences Building, 30‑32 Ngan Shing Street, Sha Tin, Hong Kong SAR, China
- Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Sha Tin, Hong Kong SAR, China
- Biomedical Laboratory Science, Department of Technology, Faculty of Health, University College Copenhagen, Copenhagen, Denmark
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Jain V, Saini D, Soren DC, Kumar VA, Vivek Kumar PR, Koya PKM, Jaikrishan G, Das B. Non-linear dose response of DNA double strand breaks in response to chronic low dose radiation in individuals from high level natural radiation areas of Kerala coast. Genes Environ 2023; 45:16. [PMID: 37127760 PMCID: PMC10150514 DOI: 10.1186/s41021-023-00273-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 04/06/2023] [Indexed: 05/03/2023] Open
Abstract
BACKGROUND The human population living in high level natural radiation areas (HLNRAs) of Kerala coast provide unique opportunities to study the biological effects of low dose and low dose rate ionizing radiation below 100 mGy. The level of radiation in this area varies from < 1.0 to 45 mGy/year. The areas with ≤ 1.50 mGy/year are considered as normal level natural radiation areas (NLNRA) and > 1.50 mGy/year, as high level natural radiation areas (HLNRA). The present study evaluated dose response relationship between DNA double strand breaks (DSBs) and background radiation dose in individuals residing in Kerala coast. Venous blood samples were collected from 200 individuals belonging to NLNRA (n = 50) and four dose groups of HLNRA; 1.51-5.0 mGy/year (n = 50), 5.01-10.0 mGy/year (n = 30), 10.01-15.0 mGy/year (n = 33), > 15.0 mGy/year (n = 37) with written informed consent. The mean dose of NLNRA and four HLNRA dose groups studied are 1.21 ± 0.21 (range: 0.57-1.49), 3.02 ± 0.95 (range: 1.57-4.93), 7.43 ± 1.48 (range: 5.01-9.75), 12.22 ± 1.47 (range: 10.21-14.99), 21.64 ± 6.28 (range: 15.26-39.88) mGy/year, respectively. DNA DSBs were quantified using γH2AX as a marker, where foci were counted per cell using fluorescence microscopy. RESULTS Our results revealed that the frequency of γH2AX foci per cell was 0.090 ± 0.051 and 0.096 ± 0.051, respectively in NLNRA and HLNRA individuals, which were not significantly different (t198 = 0.33; P = 0.739). The frequency of γH2AX foci was observed to be 0.090 ± 0.051, 0.096 ± 0.051, 0.076 ± 0.036, 0.087 ± 0.042, 0.108 ± 0.046 per cell, respectively in different dose groups of ≤ 1.50, 1.51-5.0, 5.01-10.0, 10.01-15.0, > 15.0mGy/year (ANOVA, F4,195 = 2.18, P = 0.072) and suggested non-linearity in dose response. The frequency of γH2AX foci was observed to be 0.098 ± 0.042, 0.078 ± 0.037, 0.084 ± 0.042, 0.099 ± 0.058, 0.097 ± 0.06 and 0.114 ± 0.033 per cell in the age groups of ≤ 29, 30-34, 35-39, 40-44, 45-49 and ≥ 50 years, respectively (ANOVA, F5,194 = 2.17, P = 0.059), which suggested marginal influence of age on the baseline of DSBs. Personal habits such as smoking (No v/s Yes: 0.092 ± 0.047 v/s 0.093 ± 0.048, t198 = 0.13; P = 0.895) and drinking alcohol (No v/s Yes: 0.096 ± 0.052 v/s 0.091 ± 0.045, t198 = 0.62; P = 0.538) did not show any influence on DSBs in the population. CONCLUSION The present study did not show any increase in DSBs in different dose groups of HLNRA compared to NLNRA, however, it suggested a non-linear dose response between DNA DSBs and chronic low dose radiation.
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Affiliation(s)
- Vinay Jain
- Low Level Radiation Research Section (LLRRS), Radiation Biology & Health Sciences Division (RB&HSD), Bio-Sciences Group (BSG), Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
- Homi Bhabha National Institute (HBNI), Anushakti Nagar, Trombay, Mumbai, 400 094, India
| | - Divyalakshmi Saini
- Low Level Radiation Research Section (LLRRS), Radiation Biology & Health Sciences Division (RB&HSD), Bio-Sciences Group (BSG), Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
| | - D C Soren
- Low Level Radiation Research Section (LLRRS), Radiation Biology & Health Sciences Division (RB&HSD), Bio-Sciences Group (BSG), Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
| | - V Anil Kumar
- Low Level Radiation Research Section (LLRRS), Radiation Biology & Health Sciences Division (RB&HSD), Bio-Sciences Group (BSG), Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
| | - P R Vivek Kumar
- Low Level Radiation Research Laboratory, LLRRS, RB&HSD, BSG, BARC, IRE Campus, Beach Road, Kollam, Kerala, 691 001, India
- Homi Bhabha National Institute (HBNI), Anushakti Nagar, Trombay, Mumbai, 400 094, India
| | - P K M Koya
- Low Level Radiation Research Laboratory, LLRRS, RB&HSD, BSG, BARC, IRE Campus, Beach Road, Kollam, Kerala, 691 001, India
| | - G Jaikrishan
- Low Level Radiation Research Laboratory, LLRRS, RB&HSD, BSG, BARC, IRE Campus, Beach Road, Kollam, Kerala, 691 001, India
| | - Birajalaxmi Das
- Low Level Radiation Research Section (LLRRS), Radiation Biology & Health Sciences Division (RB&HSD), Bio-Sciences Group (BSG), Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India.
- Homi Bhabha National Institute (HBNI), Anushakti Nagar, Trombay, Mumbai, 400 094, India.
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Adler A, Roth B, Lundy SD, Takeshima T, Yumura Y, Kuroda S. Sperm DNA fragmentation testing in clinical management of reproductive medicine. Reprod Med Biol 2023; 22:e12547. [PMID: 37915974 PMCID: PMC10616814 DOI: 10.1002/rmb2.12547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 09/26/2023] [Accepted: 10/12/2023] [Indexed: 11/03/2023] Open
Abstract
Background Approximately 8%-12% of couples worldwide face infertility, with infertility of individuals assigned male at birth (AMAB) contributing to at least 50% of cases. Conventional semen analysis commonly used to detect sperm abnormalities is insufficient, as 30% of AMAB patients experiencing infertility show normal results in this test. From a genetic perspective, the assessment of sperm DNA fragmentation (SDF) is important as a parameter of sperm quality. Methods In this narrative study, we review and discuss pathophysiological causes, DNA repair mechanisms, and management of high SDF. We then summarize literature exploring the association between SDF and reproductive outcomes. Main Findings Recent systematic reviews and meta-analyses have revealed a significant association between high SDF in AMAB individuals and adverse reproductive outcomes including embryo development, natural conception, intrauterine insemination, and in vitro fertilization. However, the association with live birth rates and pregnancy rates following intracytoplasmic injection remains inconclusive. The disparities among quantitative assays, inconsistent reference range values, absent high-quality prospective clinical trials, and clinical heterogeneity in AMAB patients with elevated SDF represent the main limitations affecting SDF testing. Conclusion The evaluation and management of SDF plays an important role in a subset of AMAB infertility, but widespread integration into clinical guidelines will require future high-quality clinical trials and assay standardization.
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Affiliation(s)
- Ava Adler
- Glickman Urological & Kidney InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Bradley Roth
- Glickman Urological & Kidney InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Scott D. Lundy
- Glickman Urological & Kidney InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Teppei Takeshima
- Department of Urology, Reproduction CenterYokohama City University Medical CenterYokohamaJapan
| | - Yasushi Yumura
- Department of Urology, Reproduction CenterYokohama City University Medical CenterYokohamaJapan
| | - Shinnosuke Kuroda
- Glickman Urological & Kidney InstituteCleveland Clinic FoundationClevelandOhioUSA
- Department of Urology, Reproduction CenterYokohama City University Medical CenterYokohamaJapan
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Chumsuwan N, Khongkow P, Kaewsuwan S, Kanokwiroon K. Interruptin C, a Radioprotective Agent, Derived from Cyclosorus terminans Protect Normal Breast MCF-10A and Human Keratinocyte HaCaT Cells against Radiation-Induced Damage. Molecules 2022; 27:3298. [PMID: 35630775 PMCID: PMC9142933 DOI: 10.3390/molecules27103298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/12/2022] [Accepted: 05/14/2022] [Indexed: 01/27/2023] Open
Abstract
Radiotherapy is a common method to treat cancers, with the goal of maximizing the dose to tumors while minimizing the dose to normal tissues. Radioprotectors can reduce the toxicity to normal tissues during radiotherapy. Several plant-derived compounds can function as radioprotectors by scavenging free radicals. We investigated the radioprotective activity of interruptin C from the fern Cyclosorus terminans. The molecular mechanism of interruptin C's activity in X-ray-irradiated cells was evaluated. Superoxide dismutase activity was examined to investigate the antioxidant enzyme activity. Clonogenic cell survival was also investigated following radiation exposure. DNA damage and cell cycle progression were detected using micronuclei formation assays. DNA repair after irradiation was analyzed in a γH2AX assay. The levels of the proteins related to the radioprotective responses were analyzed by Western blotting. Interruptin C increased the antioxidant enzyme activity and significantly decreased the DNA damage by reducing the γH2AX foci and micronucleus formation in irradiated MCF-10A normal breast and HaCaT human keratinocyte cells. The apoptotic protein levels decreased, whereas the antiapoptotic protein levels increased. Interruptin C pretreatment increased the survival rate of irradiated MCF-10A and HaCaT cells. Moreover, the compound did not promote the survival of MDA-MB-231 and Hs578T breast cancer cells. Therefore, interruptin C may exert radioprotective activity without enhancing cancer cell proliferation.
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Affiliation(s)
- Nipha Chumsuwan
- Department of Biomedical Sciences and Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (N.C.); (P.K.)
- Department of Radiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Pasarat Khongkow
- Department of Biomedical Sciences and Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (N.C.); (P.K.)
| | - Sireewan Kaewsuwan
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand;
- Phytomedicine and Pharmaceutical Biotechnology Excellence Center, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Kanyanatt Kanokwiroon
- Department of Biomedical Sciences and Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (N.C.); (P.K.)
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Liao L, Yan WJ, Tian CM, Li MY, Tian YQ, Zeng GQ. Knockdown of Annexin A1 Enhances Radioresistance and Inhibits Apoptosis in Nasopharyngeal Carcinoma. Technol Cancer Res Treat 2019; 17:1533034617750309. [PMID: 29357787 PMCID: PMC5784564 DOI: 10.1177/1533034617750309] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Radiotherapy is the primary treatment for nasopharyngeal carcinoma while radioresistance can hinder efficient treatment. To explore the role of annexin A1 and its potential mechanisms in radioresistance of nasopharyngeal carcinoma, human nasopharyngeal carcinoma cell line CNE2-sh annexin A1 (knockdown of annexin A1) and the control cell line CNE2-pLKO.1 were constituted and CNE2-sh annexin A1 xenograft mouse model was generated. The effect of annexin A1 knockdown on the growth of xenograft tumor after irradiation and radiation-induced DNA damage and repair was analyzed. The results of immunohistochemistry assays and Western blotting showed that the level of annexin A1 was significantly downregulated in the radioresistant nasopharyngeal carcinoma tissues or cell line compared to the radiosensitive nasopharyngeal carcinoma tissues or cell line. Knockdown of annexin A1 significantly promoted CNE2-sh annexin A1 xenograft tumor growth compared to the control groups after irradiation. Moreover, the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assays revealed that knockdown of annexin A1 significantly inhibited apoptosis in vivo compared to the control groups. We assessed the intracellular reactive oxygen species levels and the extent of radiation-induced DNA damage and repair using reactive oxygen species assay, comet assays, and immunohistochemistry assay. The results showed that knockdown of annexin A1 remarkedly reduced the intracellular reactive oxygen species levels, level of DNA double-strand breaks, and the phosphorylation level of H2AX and increased the accumulation of DNA-dependent protein kinase in nasopharyngeal carcinoma cells after irradiation. The findings suggest that knockdown of annexin A1 inhibits DNA damage via decreasing the generation of intracellular reactive oxygen species and the formation of γ-H2AX and promotes DNA repair via increasing DNA-dependent protein kinase activity and therefore improves the radioresistance in nasopharyngeal carcinoma cells. Together, our findings suggest that knockdown of annexin A1 promotes radioresistance in nasopharyngeal carcinoma and provides insights into therapeutic targets for nasopharyngeal carcinoma radiotherapy.
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Affiliation(s)
- Li Liao
- 1 School of Public Health, Central South University, Changsha, Hunan, China.,2 School of Nursing, University of South China, Hengyang, Hunan, China
| | - Wen-Jing Yan
- 2 School of Nursing, University of South China, Hengyang, Hunan, China
| | - Chun-Mei Tian
- 2 School of Nursing, University of South China, Hengyang, Hunan, China
| | - Mao-Yu Li
- 3 Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yong-Quan Tian
- 1 School of Public Health, Central South University, Changsha, Hunan, China
| | - Gu-Qing Zeng
- 2 School of Nursing, University of South China, Hengyang, Hunan, China
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Murthy V, Dacus D, Gamez M, Hu C, Wendel SO, Snow J, Kahn A, Walterhouse SH, Wallace NA. Characterizing DNA Repair Processes at Transient and Long-lasting Double-strand DNA Breaks by Immunofluorescence Microscopy. J Vis Exp 2018. [PMID: 29939192 DOI: 10.3791/57653] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The repair of double-stranded breaks (DSBs) in DNA is a highly coordinated process, necessitating the formation and resolution of multi-protein repair complexes. This process is regulated by a myriad of proteins that promote the association and disassociation of proteins to these lesions. Thanks in large part to the ability to perform functional screens of a vast library of proteins, there is a greater appreciation of the genes necessary for the double-strand DNA break repair. Often knockout or chemical inhibitor screens identify proteins involved in repair processes by using increased toxicity as a marker for a protein that is required for DSB repair. Although useful for identifying novel cellular proteins involved in maintaining genome fidelity, functional analysis requires the determination of whether the protein of interest promotes localization, formation, or resolution of repair complexes. The accumulation of repair proteins can be readily detected as distinct nuclear foci by immunofluorescence microscopy. Thus, association and disassociation of these proteins at sites of DNA damage can be accessed by observing these nuclear foci at representative intervals after the induction of double-strand DNA breaks. This approach can also identify mis-localized repair factor proteins, if repair defects do not simultaneously occur with incomplete delays in repair. In this scenario, long-lasting double-strand DNA breaks can be engineered by expressing a rare cutting endonuclease (e.g., I-SceI) in cells where the recognition site for the said enzyme has been integrated into the cellular genome. The resulting lesion is particularly hard to resolve as faithful repair will reintroduce the enzyme's recognition site, prompting another round of cleavage. As a result, differences in the kinetics of repair are eliminated. If repair complexes are not formed, localization has been impeded. This protocol describes the methodology necessary to identify changes in repair kinetics as well as repair protein localization.
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Affiliation(s)
| | | | - Monica Gamez
- Bristol Medical School, Translational Health Sciences, University of Bristol
| | - Changkun Hu
- Division of Biology, Kansas State University
| | | | | | - Andrew Kahn
- Division of Biology, Kansas State University
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Nguemgo Kouam P, Rezniczek GA, Kochanneck A, Priesch-Grzeszkowiak B, Hero T, Adamietz IA, Bühler H. Robo1 and vimentin regulate radiation-induced motility of human glioblastoma cells. PLoS One 2018; 13:e0198508. [PMID: 29864155 PMCID: PMC5986140 DOI: 10.1371/journal.pone.0198508] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 05/21/2018] [Indexed: 11/18/2022] Open
Abstract
Glioblastoma is a primary brain tumor with a poor prognosis despite of many treatment regimens. Radiotherapy significantly prolongs patient survival and remains the most common treatment. Slit2 and Robo1 are evolutionarily conserved proteins involved in axon guidance, migration, and branching of neuronal cells. New studies have shown that Slit2 and Robo1 could play important roles in leukocyte chemotaxis and glioblastoma cell migration. Therefore, we investigated whether the Slit2/Robo1 complex has an impact on the motility of glioblastoma cells and whether irradiation with therapeutic doses modulates this effect. Our results indicate that photon irradiation increases the migration of glioblastoma cells in vitro. qPCR and immunoblotting experiments in two different glioblastoma cell lines (U-373 MG and U-87 MG) with different malignancy revealed that both Slit2 and Robo1 are significantly lower expressed in the cell populations with the highest motility and that the expression was reduced after irradiation. Overexpression of Robo1 significantly decreased the motility of glioblastoma cells and inhibited the accelerated migration of wild-type cells after irradiation. Immunoblotting analysis of migration-associated proteins (fascin and focal adhesion kinase) and of the epithelial-mesenchymal-transition-related protein vimentin showed that irradiation affected the migration of glioblastoma cells by increasing vimentin expression, which can be reversed by the overexpression of Slit2 and Robo1. Our findings suggest that Robo1 expression might counteract migration and also radiation-induced migration of glioblastoma cells, a process that might be connected to mesenchymal-epithelial transition.
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Affiliation(s)
- Pascaline Nguemgo Kouam
- Institute for Molecular Oncology, Radio-Biology and Experimental Radiotherapy, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Günther A. Rezniczek
- Department of Obstetrics and Gynecology, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Anja Kochanneck
- Institute for Molecular Oncology, Radio-Biology and Experimental Radiotherapy, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Bettina Priesch-Grzeszkowiak
- Institute for Molecular Oncology, Radio-Biology and Experimental Radiotherapy, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Thomas Hero
- Department of Radiotherapy and Radio-Oncology, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Irenäus A. Adamietz
- Department of Radiotherapy and Radio-Oncology, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
| | - Helmut Bühler
- Institute for Molecular Oncology, Radio-Biology and Experimental Radiotherapy, Ruhr-Universität Bochum, Medical Research Center, Marien Hospital Herne, Herne, Germany
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Overactive type 2 cannabinoid receptor induces meiosis in fetal gonads and impairs ovarian reserve. Cell Death Dis 2017; 8:e3085. [PMID: 28981118 PMCID: PMC5682662 DOI: 10.1038/cddis.2017.496] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/29/2017] [Accepted: 08/30/2017] [Indexed: 12/27/2022]
Abstract
Type 2 cannabinoid receptor (CB2R) has been proposed to promote in vitro meiotic entry of postnatal male germ cells and to maintain the temporal progression of spermatogenesis in vivo. However, no information is presently available on the role played by CB2R in male and female fetal gonads. Here we show that in vitro pharmacological stimulation with JWH133, a CB2R agonist, induced activation of the meiotic program in both male and female fetal gonads. Upon stimulation, gonocytes initiated the meiotic program but became arrested at early stages of prophase I, while oocytes showed an increased rate of meiotic entry and progression toward more advanced stage of meiosis. Acceleration of meiosis in oocytes was accompanied by a strong increase in the percentage of γ-H2AX-positive pachytene and diplotene cells, paralleled by an increase of TUNEL-positive cells, suggesting that DNA double-strand breaks were not correctly repaired during meiosis, leading to oocyte apoptosis. Interestingly, in vivo pharmacological stimulation of CB2R in fetal germ cells through JWH133 administration to pregnant females caused a significant reduction of primordial and primary follicles in the ovaries of newborns with a consequent depletion of ovarian reserve and reduced fertility in adult life, while no alterations of spermatogenesis in the testis of the offspring were detected. Altogether our findings highlight a pro-meiotic role of CB2R in male and female germ cells and suggest that the use of cannabis in pregnant female might represent a risk for fertility and reproductive lifespan in female offspring.
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9
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Suchorska WM, Augustyniak E, Łukjanow M. Comparison of the early response of human embryonic stem cells and human induced pluripotent stem cells to ionizing radiation. Mol Med Rep 2017; 15:1952-1962. [PMID: 28259963 PMCID: PMC5364988 DOI: 10.3892/mmr.2017.6270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 01/09/2017] [Indexed: 12/14/2022] Open
Abstract
Despite the well-demonstrated efficacy of stem cell (SC) therapy, this approach has a number of key drawbacks. One important concern is the response of pluripotent SCs to treatment with ionizing radiation (IR), given that SCs used in regenerative medicine will eventually be exposed to IR for diagnostic or treatment-associated purposes. Therefore, the aim of the present study was to examine and compare early IR-induced responses of pluripotent SCs to assess their radioresistance and radiosensitivity. In the present study, 3 cell lines; human embryonic SCs (hESCs), human induced pluripotent SCs (hiPSCs) and primary human dermal fibroblasts (PHDFs); were exposed to IR at doses ranging from 0 to 15 gray (Gy). Double strand breaks (DSBs), and the gene expression of the following DNA repair genes were analyzed: P53; RAD51; BRCA2; PRKDC; and XRCC4. hiPSCs demonstrated greater radioresistance, as fewer DSBs were identified, compared with hESCs. Both pluripotent SC lines exhibited distinct gene expression profiles in the most common DNA repair genes that are involved in homologous recombination, non-homologous end-joining and enhanced DNA damage response following IR exposure. Although hESCs and hiPSCs are equivalent in terms of capacity for pluripotency and differentiation into 3 germ layers, the results of the present study indicate that these 2 types of SCs differ in gene expression following exposure to IR. Consequently, further research is required to determine whether hiPSCs and hESCs are equally safe for application in clinical practice. The present study contributes to a greater understanding of DNA damage response (DDR) mechanisms activated in pluripotent SCs and may aid in the future development of safe SC-based clinical protocols.
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Affiliation(s)
| | - Ewelina Augustyniak
- Radiobiology Laboratory, Greater Poland Cancer Centre, 61‑866 Poznan, Poland
| | - Magdalena Łukjanow
- Radiobiology Laboratory, Greater Poland Cancer Centre, 61‑866 Poznan, Poland
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Zhao J, Zhou M, Li C. Synthetic nanoparticles for delivery of radioisotopes and radiosensitizers in cancer therapy. Cancer Nanotechnol 2016; 7:9. [PMID: 27909463 PMCID: PMC5112292 DOI: 10.1186/s12645-016-0022-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 11/02/2016] [Indexed: 12/11/2022] Open
Abstract
Radiotherapy has been, and will continue to be, a critical modality to treat cancer. Since the discovery of radiation-induced cytotoxicity in the late 19th century, both external and internal radiation sources have provided tremendous benefits to extend the life of cancer patients. Despite the dramatic improvement of radiation techniques, however, one challenge persists to limit the anti-tumor efficacy of radiotherapy, which is to maximize the deposited dose in tumor while sparing the rest of the healthy vital organs. Nanomedicine has stepped into the spotlight of cancer diagnosis and therapy during the past decades. Nanoparticles can potentiate radiotherapy by specifically delivering radionuclides or radiosensitizers into tumors, therefore enhancing the efficacy while alleviating the toxicity of radiotherapy. This paper reviews recent advances in synthetic nanoparticles for radiotherapy and radiosensitization, with a focus on the enhancement of in vivo anti-tumor activities. We also provide a brief discussion on radiation-associated toxicities as this is an area that, up to date, has been largely missing in the literature and should be closely examined in future studies involving nanoparticle-mediated radiosensitization.
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Affiliation(s)
- Jun Zhao
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Road, Houston, TX 77054 USA
| | - Min Zhou
- Institute of Translational Medicine, Zhejiang University, Hangzhou, 310009 Zhejiang China
| | - Chun Li
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Road, Houston, TX 77054 USA
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11
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Rodd AL, Ververis K, Sayakkarage D, Khan AW, Rafehi H, Ziemann M, Loveridge SJ, Lazarus R, Kerr C, Lockett T, El-Osta A, Karagiannis TC, Bennett LE. RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells. Food Funct 2015; 6:2507-24. [PMID: 26114728 DOI: 10.1039/c5fo00467e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Anti-proliferative and pro-apoptotic effects of Bay leaf (Laurus nobilis) in mammalian cancer and HT-29 adenocarcinoma cells have been previously attributed to effects of polyphenolic and essential oil chemical species. Recently, we demonstrated differentiated growth-regulating effects of high (HFBL) versus low molecular mass (LFBL) aqueous fractions of bay leaf and now confirm by comparative effects on gene expression, that HFBL and LFBL suppress HT-29 growth by distinct mechanisms. Induction of intra-cellular lesions including DNA strand breakage by extra-cellular HFBL, invoked the hypothesis that iron-mediated reactive oxygen species with capacity to penetrate cell membrane, were responsible for HFBL-mediated effects, supported by equivalent effects of HFBL in combination with γ radiation. Activities of HFBL and LFBL were interpreted to reflect differentiated responses to iron-mediated reactive oxygen species (ROS), occurring either outside or inside cells. In the presence of LFBL, apoptotic death was relatively delayed compared with HFBL. ROS production by LFBL mediated p53-dependent apoptosis and recovery was suppressed by promoting G1/S phase arrest and failure of cellular tight junctions. In comparison, intra-cellular anti-oxidant protection exerted by LFBL was absent for extra-cellular HFBL (likely polysaccharide-rich), which potentiated more rapid apoptosis by producing DNA double strand breaks. Differentiated effects on expression of genes regulating ROS defense and chromatic condensation by LFBL versus HFBL, were observed. The results support ferrous iron in cell culture systems and potentially in vivo, can invoke different extra-cellular versus intra-cellular ROS-mediated chemistries, that may be regulated by exogenous, including dietary species.
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Affiliation(s)
- Annabelle L Rodd
- Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria, Australia
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Shifts in developmental timing, and not increased levels of experience-dependent neuronal activity, promote barrel expansion in the primary somatosensory cortex of rats enucleated at birth. PLoS One 2013; 8:e54940. [PMID: 23372796 PMCID: PMC3556040 DOI: 10.1371/journal.pone.0054940] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 12/17/2012] [Indexed: 11/19/2022] Open
Abstract
Birth-enucleated rodents display enlarged representations of whiskers (i.e., barrels of the posteromedial subfield) in the primary somatosensory cortex. Although the historical view maintains that barrel expansion is due to incremental increases in neuronal activity along the trigeminal pathway during postnatal development, recent evidence obtained in experimental models of intramodal plasticity challenges this view. Here, we re-evaluate the role of experience-dependent neuronal activity on barrel expansion in birth-enucleated rats by combining various anatomical methods and sensory deprivation paradigms. We show that barrels in birth-enucleated rats were already enlarged by the end of the first week of life and had levels of metabolic activity comparable to those in control rats at different ages. Dewhiskering after the postnatal period of barrel formation did not prevent barrel expansion in adult, birth-enucleated rats. Further, dark rearing and enucleation after barrel formation did not lead to expanded barrels in adult brains. Because incremental increases of somatosensory experience did not promote barrel expansion in birth-enucleated rats, we explored whether shifts of the developmental timing could better explain barrel expansion during the first week of life. Accordingly, birth-enucleated rats show earlier formation of barrels, accelerated growth of somatosensory thalamocortical afferents, and an earlier H4 deacetylation. Interestingly, when H4 deacetylation was prevented with a histone deacetylases inhibitor (valproic acid), barrel specification timing returned to normal and barrel expansion did not occur. Thus, we provide evidence supporting that shifts in developmental timing modulated through epigenetic mechanisms, and not increased levels of experience dependent neuronal activity, promote barrel expansion in the primary somatosensory cortex of rats enucleated at birth.
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Age- and oxidative stress-induced DNA damage in Drosophila intestinal stem cells as marked by Gamma-H2AX. Exp Gerontol 2012; 47:401-5. [DOI: 10.1016/j.exger.2012.02.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 01/20/2012] [Accepted: 02/15/2012] [Indexed: 01/09/2023]
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Ververis K, Rodd AL, Tang MM, El-Osta A, Karagiannis TC. Histone deacetylase inhibitors augment doxorubicin-induced DNA damage in cardiomyocytes. Cell Mol Life Sci 2011; 68:4101-14. [PMID: 21584806 PMCID: PMC11115072 DOI: 10.1007/s00018-011-0727-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 04/19/2011] [Accepted: 05/03/2011] [Indexed: 01/11/2023]
Abstract
Histone deacetylase inhibitors have emerged as a new class of anticancer therapeutics with suberoylanilide hydroxamic acid (Vorinostat) and depsipeptide (Romidepsin) already being approved for clinical use. Numerous studies have identified that histone deacetylase inhibitors will be most effective in the clinic when used in combination with conventional cancer therapies such as ionizing radiation and chemotherapeutic agents. One promising combination, particularly for hematologic malignancies, involves the use of histone deacetylase inhibitors with the anthracycline, doxorubicin. However, we previously identified that trichostatin A can potentiate doxorubicin-induced hypertrophy, the dose-limiting side-effect of the anthracycline, in cardiac myocytes. Here we have the extended the earlier studies and evaluated the effects of combinations of the histone deacetylase inhibitors, trichostatin A, valproic acid and sodium butyrate on doxorubicin-induced DNA double-strand breaks in cardiomyocytes. Using γH2AX as a molecular marker for the DNA lesions, we identified that all of the broad-spectrum histone deacetylase inhibitors tested augment doxorubicin-induced DNA damage. Furthermore, it is evident from the fluorescence photomicrographs of stained nuclei that the histone deacetylase inhibitors also augment doxorubicin-induced hypertrophy. These observations highlight the importance of investigating potential side-effects, in relevant model systems, which may be associated with emerging combination therapies for cancer.
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Affiliation(s)
- Katherine Ververis
- Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 75 Commercial Road, Melbourne, VIC Australia
- Department of Anatomy and Cell Biology, The University of Melbourne, Parkville, VIC Australia
| | - Annabelle L. Rodd
- Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 75 Commercial Road, Melbourne, VIC Australia
- Department of Pathology, The University of Melbourne, Parkville, VIC Australia
| | - Michelle M. Tang
- Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 75 Commercial Road, Melbourne, VIC Australia
- Epigenetics in Human Health and Disease, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, VIC Australia
| | - Assam El-Osta
- Department of Pathology, The University of Melbourne, Parkville, VIC Australia
- Epigenetics in Human Health and Disease, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, VIC Australia
- Epigenomics Profiling Facility, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, VIC Australia
- Faculty of Medicine, Monash University, Melbourne, VIC Australia
| | - Tom C. Karagiannis
- Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 75 Commercial Road, Melbourne, VIC Australia
- Department of Pathology, The University of Melbourne, Parkville, VIC Australia
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Schisano B, Tripathi G, McGee K, McTernan PG, Ceriello A. Glucose oscillations, more than constant high glucose, induce p53 activation and a metabolic memory in human endothelial cells. Diabetologia 2011; 54:1219-26. [PMID: 21287141 DOI: 10.1007/s00125-011-2049-0] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 12/07/2010] [Indexed: 10/18/2022]
Abstract
AIMS/HYPOTHESIS Damage persists in HUVECs exposed to a constant high glucose concentration long after glucose normalisation, a phenomenon termed 'metabolic memory'. Evaluation of the effects of exposure of HUVECs to oscillating high glucose on the induction of markers of oxidative stress and DNA damage (phospho-γ-histone H2AX and PKCδ) and onset of metabolic memory, and the possible role of the tumour suppressor transcriptional factor p53 is of pivotal interest. METHODS HUVECs were incubated for 3 weeks in 5 or 25 mmol/l glucose or oscillating glucose (24 h in 5 mmol/l glucose followed by 24 h in 25 mmol/l glucose) or for 1 week in constant 5 mmol/l glucose after being exposed for 2 weeks to continuous 25 mmol/l high glucose or oscillating glucose. Transcriptional activity of p53 was also evaluated in the first 24 h after high glucose exposure. RESULTS High constant glucose upregulated phospho-γ-histone H2AX and protein kinase C (PKC)δ compared with control. Oscillating glucose was even more effective than both normal and constant high glucose. Both constant and oscillating glucose resulted in a memory effect, which was more pronounced in the oscillating condition. Transcriptional activity of p53 peaked 6 h after glucose exposure, showing a predicted oscillatory behaviour. CONCLUSIONS/INTERPRETATION Exposure to oscillating glucose was more deleterious than constant high glucose and induced a metabolic memory after glucose normalisation. Hyperactivation of p53 during glucose oscillation might be due to the absence of consistent feedback inhibition during each glucose spike and might account for the worse outcome of this condition.
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Affiliation(s)
- B Schisano
- Clinical Science Research Institute (CSRI), Warwick Medical School, University of Warwick, University Hospital-Walsgrave Campus, Coventry, CV2 2DX, UK
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Abstract
Histone deacetylase inhibitors represent a new class of anticancer therapeutics and the expectation is that they will be most effective when used in combination with conventional cancer therapies, such as the anthracycline, doxorubicin. The dose-limiting side effect of doxorubicin is severe cardiotoxicity and evaluation of the effects of combinations of the anthracycline with histone deacetylase inhibitors in relevant models is important. We used a well-established in vitro model of doxorubicin-induced hypertrophy to examine the effects of the prototypical histone deacetylase inhibitor, Trichostatin A. Our findings indicate that doxorubicin modulates the expression of the hypertrophy-associated genes, ventricular myosin light chain-2, the alpha isoform of myosin heavy chain and atrial natriuretic peptide, an effect which is augmented by Trichostatin A. Furthermore, we show that Trichostatin A amplifies doxorubicin-induced DNA double strand breaks, as assessed by γH2AX formation. More generally, our findings highlight the importance of investigating potential side effects that may be associated with emerging combination therapies for cancer.
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Photosensitization by iodinated DNA minor groove binding ligands: Evaluation of DNA double-strand break induction and repair. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 103:145-52. [PMID: 21440453 DOI: 10.1016/j.jphotobiol.2011.02.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 02/17/2011] [Accepted: 02/28/2011] [Indexed: 01/09/2023]
Abstract
Iodinated DNA minor groove binding bibenzimidazoles represent a unique class of UVA photosensitizer and their extreme photopotency has been previously characterized. Earlier studies have included a comparison of three isomers, referred to as ortho-, meta- and para-iodoHoechst, which differ only in the location of the iodine substituent in the phenyl ring of the bibenzimidazole. DNA breakage and clonogenic survival studies in human erythroleukemic K562 cells have highlighted the higher photo-efficiency of the ortho-isomer (subsequently designated UV(A)Sens) compared to the meta- and para-isomers. In this study, the aim was to compare the induction and repair of DNA double-strand breaks induced by the three isomers in K562 cells. Further, we examined the effects of the prototypical broad-spectrum histone deacetylase inhibitor, Trichostatin A, on ortho-iodoHoechst/UVA-induced double-strand breaks in K562 cells. Using γH2AX as a molecular marker of the DNA lesions, our findings indicate a disparity in the induction and particularly, in the repair kinetics of double-strand breaks for the three isomers. The accumulation of γH2AX foci induced by the meta- and para-isomers returned to background levels within 24 and 48 h, respectively; the number of γH2AX foci induced by ortho-iodoHoechst remained elevated even after incubation for 96 h post-irradiation. These findings provide further evidence that the extreme photopotency of ortho-iodoHoechst is due to not only to the high quantum yield of dehalogenation, but also to the severity of the DNA lesions which are not readily repaired. Finally, our findings which indicate that Trichostatin A has a remarkable potentiating effect on ortho-iodoHoechst/UVA-induced DNA lesions are encouraging, particularly in the context of cutaneous T-cell lymphoma, for which a histone deacetylase inhibitor is already approved for therapy. This finding prompts further evaluation of the potential of combination therapies.
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