Read by QxMD icon Read

h2ax and irradiation

Fei Lu, Xiaojun Wu, Feng Yin, Christina Chia-Fang Lee, Min Yu, Ivailo S Mihaylov, Jiekai Yu, Hong Sun, Hui Zhang
DNA replication licensing occurs on chromatin, but how the chromatin template is regulated for replication remains mostly unclear. Here, we have analyzed the requirement of histone methyltransferases for a specific type of replication: the DNA re-replication induced by the downregulation of either Geminin, an inhibitor of replication licensing protein CDT1, or the CRL4CDT2 ubiquitin E3 ligase. We found that siRNA-mediated reduction of essential components of the MLL-WDR5-RBBP5 methyltransferase complexes including WDR5 or RBBP5, which transfer methyl groups to histone H3 at K4 (H3K4), suppressed DNA re-replication and chromosomal polyploidy...
October 15, 2016: Biology Open
Michael M Im, Sheryl A Flanagan, Jeffrey J Ackroyd, Brendan Knapp, Aaron Kramer, Donna S Shewach
Gemcitabine (dFdCyd) shows broad antitumor activity in solid tumors in chemotherapeutic regimens or when combined with ionizing radiation (radiosensitization). While it is known that mismatches in DNA are necessary for dFdCyd radiosensitization, the critical event resulting in radiosensitization has not been identified. Here we hypothesized that late DNA damage (≥24 h after drug washout/irradiation) is a causal event in radiosensitization by dFdCyd, and that homologous recombination repair (HRR) is required for this late DNA damage...
October 14, 2016: Radiation Research
Peizhou Jiang, Peng Huang, Shu-Hui Yen, Abba C Zubair, Dennis W Dickson
BACKGROUND AIMS: Aberrant production of reactive oxygen species (ROS) and its impact on the integrity of genomic DNA have been considered one of the major risk factors for the loss of dopaminergic neurons in Parkinson's disease (PD). Stem cell transplantation as a strategy to replenish new functional neurons has great potential for PD treatment. However, limited survival of stem cells post-transplantation has always been an obstacle ascribed to the existence of neurotoxic environment in PD patients...
October 6, 2016: Cytotherapy
Pavel Lobachevsky, Trevor Leong, Patricia Daly, Jai Smith, Nickala Best, Ella R Thompson, Na Li, Ian G Campbell, Roger F Martin, Olga A Martin
A small percentage of cancer radiotherapy patients develop abnormally severe side effects as a consequence of intrinsic radiosensitivity. We analysed the γ-H2AX response to ex-vivo irradiation of peripheral blood lymphocytes (PBL) and plucked eyebrow hair follicles from 16 patients who developed severe late radiation toxicity following radiotherapy, and 12 matched control patients. Longer retention of the γ-H2AX signal and lower colocalization efficiency of repair factors in over-responding patients confirmed that DNA repair in these individuals was compromised...
September 28, 2016: Cancer Letters
Kathleen A Bridges, Xingxing Chen, Huifeng Liu, Crosby Rock, Thomas A Buchholz, Stuart D Shumway, Heath D Skinner, Raymond E Meyn
Radiotherapy is commonly used to treat a variety of solid tumors but improvements in the therapeutic ratio are sorely needed. The aim of this study was to assess the Chk1 kinase inhibitor, MK-8776, for its ability to radiosensitize human tumor cells. Cells derived from NSCLC and HNSCC cancers were tested for radiosensitization by MK-8776. The ability of MK-8776 to abrogate the radiation-induced G2 block was determined using flow cytometry. Effects on repair of radiation-induced DNA double strand breaks (DSBs) were determined on the basis of rad51, γ-H2AX and 53BP1 foci...
September 28, 2016: Oncotarget
Jayne Moquet, Stephen Barnard, Albena Staynova, Carita Lindholm, Octávia Monteiro Gil, Vanda Martins, Ute Rößler, Anne Vral, Charlot Vandevoorde, Maria Wojewódzka, Kai Rothkamm
PURPOSE: Within the EU RENEB project, seven laboratories have taken part in training and harmonisation activities to strengthen triage gamma-H2AX-based radiation exposure assessment. This has culminated in a second triage biodosimetry exercise. MATERIALS AND METHODS: Whole blood and separated lymphocyte samples were homogenously irradiated with (60)Co gamma rays at 0.5, 2.5 (blind samples), 0 and 2 Gy (reference samples). Following post-exposure incubations of 4 and 24 h, 16 samples were shipped on ice packs to each partner...
August 15, 2016: International Journal of Radiation Biology
Younghyun Lee, Huizi Keiko Li, Aya Masaoka, Shigeaki Sunada, Hirokazu Hirakawa, Akira Fujimori, Jac A Nickoloff, Ryuichi Okayasu
BACKGROUND AND PURPOSE: PU-H71 is a purine-scaffold Hsp90 inhibitor developed to overcome limitations of conventional Hsp90 inhibitors. This study was designed to investigate the combined effect of PU-H71 and heavy ion irradiation on human tumor and normal cells. MATERIALS AND METHODS: The effects of PU-H71 were determined by monitoring cell survival by colony formation, and DNA double-strand break (DSB) repair by γ-H2AX foci and immuno-blotting DSB repair proteins...
September 22, 2016: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
Yi-Fan Chen, Jonathan J Cho, Tsai-Hua Huang, Chao-Neng Tseng, Eng-Yen Huang, Chung-Lung Cho
ROGDI is a protein that contains a leucine zipper domain and may be involved in cell proliferation. In addition, ROGDI is associated with genome stability by regulating the activity of a DNA damage marker, γ-H2AX. The role of ROGDI in tumor radiosensitization has not been investigated. Previous studies have indicated that radiosensitivity is associated with DNA repair and the cell cycle. In general, the G2/M DNA damage checkpoint is more sensitive to radiation, whereas the G1/S phase transition is more resistant to radiation...
August 12, 2016: Cancer Biology & Therapy
Otilija D Keta, Danijela V Todorović, Tanja M Bulat, Pablo Ga Cirrone, Francesco Romano, Giacomo Cuttone, Ivan M Petrović, Aleksandra M Ristić Fira
The aim of this study was to investigate effects of irradiations with the therapeutic proton and carbon ion beams in two non-small cell lung cancers, CRL5876 adenocarcinoma and HTB177 large cell lung carcinoma. The DNA damage response dynamics, cell cycle regulation, and cell death pathway activation were followed. Viability of both cell lines was lower after carbon ions compared to the therapeutic proton irradiations. HTB177 cells showed higher recovery than CRL5876 cells seven days following the treatments, but the survival rates of both cell lines were lower after exposure to carbon ions with respect to therapeutic protons...
September 15, 2016: Experimental Biology and Medicine
Lu Lu, Jiali Dong, Deguan Li, Junling Zhang, Saijun Fan
We have reported that hematopoietic system injury induced by total body irradiation (TBI) leads to generation of intracellular reactive oxygen species (ROS) and DNA damage, which are ameliorated by antioxidant agents. In the present study, we reported that administration of DIM, a potent antioxidant agent, not only protected mice against TBI-induced lethality, also ameliorated TBI-induced hematopoietic injury. The latter effect was probably attributable to DIM's inhibition of TBI-induced increases in ROS production in hematopoietic stem cells (HSCs) and the phosphorylation of histone H2AX (γ-H2AX)...
September 5, 2016: Free Radical Biology & Medicine
Hongjuan Zhang, Fang Wang, Chunjie Mao, Zuncheng Zhang, Shengjun Fu, Jianzhong Lu, Zhenxing Zhai, Renju Li, Shuwen Li, Ron Rodriguez, Zhiping Wang
PURPOSE: Gene therapy combined with radiation has shown promising potential for the treatment of tumors. This paper aimed to clarify the synergistic effect of radiotherapy combined with the bladder cancer tissue-specific oncolytic adenovirus (Ad-PSCAE-UPII-E1A) on bladder cancer cells and to study the underlying synergy mechanisms of the combined treatment. MATERIALS AND METHODS: The Adenovirus carrying E1A under control of UPII promoter and prostate stem cell antigen enhancer (PSCAE) were successfully constructed...
October 14, 2016: International Journal of Radiation Biology
Tomoyuki Kawase, Kazuhiro Okuda, Masaki Nagata, Makoto Tsuchimochi, Hiromasa Yoshie, Koh Nakata
Purpose To assure the quality of cells to be used in cell therapy, we examined the applicability of digital holographic microscopy (DHM) for non-invasive, quantitative assessment of changes in cell morphology. Materials and methods Mesenchymal stem cells derived from adipose tissue (MSC-AT) and bone marrow (MSC-BM), in addition to human alveolar periosteal cells (PCs) as a reference, were γ-ray irradiated (1 and 4 Gy), and their morphological changes were quantified without fixation using holographic microscopy...
September 1, 2016: International Journal of Radiation Biology
S Raschke, S Spickermann, T Toncian, M Swantusch, J Boeker, U Giesen, G Iliakis, O Willi, F Boege
Ultra-short proton pulses originating from laser-plasma accelerators can provide instantaneous dose rates at least 10(7)-fold in excess of conventional, continuous proton beams. The impact of such extremely high proton dose rates on A549 human lung cancer cells was compared with conventionally accelerated protons and 90 keV X-rays. Between 0.2 and 2 Gy, the yield of DNA double strand breaks (foci of phosphorylated histone H2AX) was not significantly different between the two proton sources or proton irradiation and X-rays...
2016: Scientific Reports
Aurélie Henry, Marie-Julie Nokin, Natacha Leroi, François Lallemand, Jérémy Lambert, Nicolas Goffart, Patrick Roncarati, Elettra Bianchi, Paul Peixoto, Arnaud Blomme, Andrei Turtoi, Olivier Peulen, Yvette Habraken, Félix Scholtes, Philippe Martinive, Philippe Delvenne, Bernard Rogister, Vincent Castronovo, Akeila Bellahcène
Glioblastoma (GBM) represents the most aggressive and common solid human brain tumor. We have recently demonstrated the importance of osteopontin (OPN) in the acquisition/maintenance of stemness characters and tumorigenicity of glioma initiating cells. Consultation of publicly available TCGA database indicated that high OPN expression correlated with poor survival in GBM patients. In this study, we explored the role of OPN in GBM radioresistance using an OPN-depletion strategy in U87-MG, U87-MG vIII and U251-MG human GBM cell lines...
August 22, 2016: Oncotarget
D Ding, Y Zhang, J Wang, X Zhang, Y Gao, L Yin, Q Li, J Li, H Chen
Human peripheral blood lymphocytes (HPBLs) are one of the most sensitive cells to ionizing radiation (IR) in the human body, and IR-induced DNA damage and functional impairment of HPBLs are the adverse consequences of IR accidents and major side effects of radiotherapy. Phosphorylated H2AX (γH2AX) is a sensitive marker for DNA double-strand breaks, but the role and regulation of the pan-nuclear γH2AX response in HPBLs after IR remain unclear. We herein demonstrated that the pan-nuclear γH2AX signals were increased in a time- and dose-dependent manner, colocalized with >94% of TUNEL apoptotic staining, and displayed a typical apoptotic pattern in resting HPBLs after low LET X-ray IR...
2016: Cell Death Discovery
Anu Pal, Shamshad Alam, Sandeep Mittal, Nidhi Arjaria, Jai Shankar, Mahadeo Kumar, Dhirendra Singh, Alok Kumar Pandey, Kausar Mahmood Ansari
UV-induced reactive oxygen species (ROS) have been implicated in photocarcinogenesis and skin aging. This is because UV-induced ROS can induce DNA damage that, if unrepaired, can lead to carcinogenesis. Sunscreens contain UV attenuators, such as organic chemical and/or physical UV filters, which can prevent all forms of damage from UV irradiation. In recent years, the effective broad-spectrum UV attenuation properties of ZnO-nanoparticles (ZnO-NPs) have made them attractive as active components in sunscreens and other personal care products...
September 1, 2016: Mutation Research. Genetic Toxicology and Environmental Mutagenesis
Wei Ma, Chao-Nan Ma, Nan-Nan Zhou, Xian-Dong Li, Yi-Jie Zhang
MicroRNAs (miRNAs) are believed to be resistant against radiotherapy in certain types of cancers. The aim of our study was to determine the clinical application of miRNAs in non-small cell lung cancer (NSCLC). Sixty NSCLC tissue samples and adjacent histologically normal tissues were obtained for miRNAs microarray analysis and validated by RT-qPCR. Correlation between miRNA expression level and clinicopathological features was evaluated. Our study examined the influence of changed miRNA expression on the damaged DNA and its associated radio sensitivity...
2016: Scientific Reports
Almudena Pérez-Sánchez, Enrique Barrajón-Catalán, María Herranz-López, Julián Castillo, Vicente Micol
BACKGROUND: Solar ultraviolet (UV) radiation is one of the main causes of a variety of cutaneous disorders, including photoaging and skin cancer. Its UVB component (280-315nm) leads to oxidative stress and causes inflammation, DNA damage, p53 induction and lipid and protein oxidation. Recently, an increase in the use of plant polyphenols with antioxidant and anti-inflammatory properties has emerged to protect human skin against the deleterious effects of sunlight. OBJECTIVE: This study evaluates the protective effects of lemon balm extract (LBE) (Melissa Officinalis, L) and its main phenolic compound rosmarinic acid (RA) against UVB-induced damage in human keratinocytes...
August 4, 2016: Journal of Dermatological Science
Donna L Nile, Colin Rae, Iain J Hyndman, Mark N Gaze, Robert J Mairs
BACKGROUND: The radiopharmaceutical (131)I-meta-iodobenzylguanidine ((131)I-MIBG) is an effective treatment for neuroblastoma. However, maximal therapeutic benefit from (131)I-MIBG is likely to be obtained by its combination with chemotherapy. We previously reported enhanced antitumour efficacy of (131)I-MIBG by inhibition of the poly(ADP-ribose) polymerase-1 (PARP-1) DNA repair pathway using the phenanthridinone derivative PJ34. Recently developed alternative PARP-1 inhibitors have greater target specificity and are expected to be associated with reduced toxicity to normal tissue...
2016: BMC Cancer
Ki-Man Lee, Ui-Seob Lee, Eun-Hee Kim
An alpha particle irradiator has been built in the Radiation Bioengineering Laboratory at Seoul National University (SNU) to investigate the cellular responses to alpha emissions from radon and the progeny. This irradiator is designed to have the energy of alpha particles entering target cells similar to that of alpha emissions from the radon progeny Po-218 and Po-214 residing in the human respiratory tract. For the SNU alpha particle irradiator, an irradiation system is equipped with cell dishes of 4µm thick Mylar bottom and a special setup of cells on slide for gamma-H2AX assay...
September 2016: Applied Radiation and Isotopes
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"