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Journal of cell science, 132
2019

Synthetic lethality of cytolytic HSV-1 in cancer cells with ATRX and PML deficiency.

Han, Mingqi, Napier, Christine E, Frölich, Sonja, Teber, Erdahl, Wong, Ted, Noble, Jane R, Choi, Eugene H Y, Everett, Roger D, Cesare, Anthony J, Reddel, Roger R

Cancers that utilize the alternative lengthening of telomeres (ALT) mechanism for telomere maintenance are often difficult to treat and have a poor prognosis. They are also commonly deficient for expression of ATRX protein, a repressor of ALT activity, and a component of promyelocytic leukemia nuclear bodies (PML NBs) that are required for intrinsic immunity to various viruses. Here, we asked whether ATRX deficiency creates a vulnerability in ALT cancer cells that could be exploited for therapeutic purposes. We showed in a range of cell types that a mutant herpes simplex virus type 1 (HSV-1) lacking ICP0, a protein that degrades PML NB components including ATRX, was ten- to one thousand-fold more effective in infecting ATRX-deficient cells than wild-type ATRX-expressing cells. Infection of co-cultured primary and ATRX-deficient cancer cells revealed that mutant HSV-1 selectively killed ATRX-deficient cells. Sensitivity to mutant HSV-1 infection also correlated inversely with PML protein levels, and we showed that ATRX upregulates PML expression at both the transcriptional and post-transcriptional levels. These data provide a basis for predicting, based on ATRX or PML levels, which tumors will respond to a selective oncolytic herpesvirus.

Digital object identifier (DOI): 10.1242/jcs.222349

European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences, 129, 181--189
2019

Multi- and unilamellar liposomal encapsulation of ciprofloxacin as ways to modify its phototoxicity and photodegradation.

Zgadzaj, A, Giebułtowicz, J, Gubernator, J, Podbielska, M, Sommer, S, Zaremba-Czogalla, M, Nałęcz-Jawecki, G

Liposomes are vesicular preparations that improve bioavailability of many pharmaceuticals, used even in ocular therapy. In addition, it is well documented that vesicular carriers could affect the photodegradation of molecules encapsulated inside, which is especially important for drugs that may exhibit phototoxicity when they are applied topically on sensitive light-exposed tissues. In this study, we investigated the effect of ciprofloxacin encapsulation into liposomes on its photodegradation, phototoxicity and photogenotoxicity in vitro at the concentration ranges applied in ophthalmology. We tested two variants of liposomes: large unilamellar vesicles (LUV) and multilamellar vesicles (MLV) in comparison to antibiotic solutions without phospholipids (CPX). On the basis of our research, the kinetics of ciprofloxacin photolysis was the fastest in formulations with vesicles with low drug-to-lipid ratio. Depending on vesicles type (drug-to-lipid ratio, MLV or LUV) and time of irradiation different degradants were produced. We proposed structures of the novel ciprofloxacin photolysis products characteristic for vesicles. We did not notice any photoprotective effect of application of ciprofloxacin encapsulation into liposomes, but it significantly affected the photodegradation product profile of the drug and the Photo-Irritation-Factor of the vesicular preparations. In the MTT and micronucleus assays impact of encapsulation was not as clearly visible.

Digital object identifier (DOI): 10.1016/j.ejps.2019.01.006

Cells, 8
2019

Oxidative Stress Induces Telomere Dysfunction and Senescence by Replication Fork Arrest.

Coluzzi, Elisa, Leone, Stefano, Sgura, Antonella

Oxidative DNA damage, particularly 8-oxoguanine, represents the most frequent DNA damage in human cells, especially at the telomeric level. The presence of oxidative lesions in the DNA can hinder the replication fork and is able to activate the DNA damage response. In this study, we wanted to understand the mechanisms by which oxidative damage causes telomere dysfunction and senescence in human primary fibroblasts. After acute oxidative stress at telomeres, our data demonstrated a reduction in TRF1 and TRF2, which are involved in proper telomere replication and T-loop formation, respectively. Furthermore, we observed a higher level of γH2AX with respect to 53BP1 at telomeres, suggesting a telomeric replication fork stall rather than double-strand breaks. To confirm this finding, we studied the replication of telomeres by Chromosome Orientation-FISH (CO-FISH). The data obtained show an increase in unreplicated telomeres after hydrogen peroxide treatment, corroborating the idea that the presence of 8-oxoG can induce replication fork arrest at telomeres. Lastly, we analyzed the H3K9me3 histone mark after oxidative stress at telomeres, and our results showed an increase of this marker, most likely inducing the heterochromatinization of telomeres. These results suggest that 8-oxoG is fundamental in oxidative stress-induced telomeric damage, principally causing replication fork arrest.

Digital object identifier (DOI): 10.3390/cells8010019

Biochemical and biophysical research communications, 511, 658--664
2019

Distinctive Krebs cycle remodeling in iPSC-derived neural and mesenchymal stem cells.

Benlamara, Sarah, Aubry, Laetitia, Fabregue, Julien, Bénit, Paule, Rustin, Pierre, Rak, Malgorzata

Mitochondria play a vital role in proliferation and differentiation and their remodeling in the course of differentiation is related to the variable energy and metabolic needs of the cell. In this work, we show a distinctive mitochondrial remodeling in human induced pluripotent stem cells differentiated into neural or mesenchymal progenitors. While leading to upregulation of the citrate synthase-α-ketoglutarate dehydrogenase segment of the Krebs cycle and increased respiratory chain activities and respiration in the mesenchymal stem cells, the remodeling in the neural stem cells resulted in downregulation of α-ketoglutarate dehydrogenase, upregulation of isocitrate dehydrogenase 2 and the accumulation of α-ketoglutarate. The distinct, lineage-specific changes indicate an involvement of these Krebs cycle enzymes in cell differentiation.

Digital object identifier (DOI): 10.1016/j.bbrc.2019.02.033

Annals of laboratory medicine, 39, 91--95
2019

Dose Estimation Curves Following In Vitro X-ray Irradiation Using Blood From Four Healthy Korean Individuals.

Jang, Mi Ae, Han, Eun Ae, Lee, Jin Kyung, Cho, Kwang Hwan, Shin, Hee Bong, Lee, You Kyoung

Cytogenetic dosimetry is useful for evaluating the absorbed dose of ionizing radiation based on analysis of radiation-induced chromosomal aberrations. We created two types of dose-response calibration curves for dicentric chromosomes (DC) and translocations (TR) induced by X-ray irradiation, using an electron linear accelerator, which is the most frequently used medical device in radiotherapy. We irradiated samples from four healthy Korean individuals and compared the resultant curves between individuals. Aberration yields were studied in a total of 31,800 and 31,725 metaphases for DC and TR, respectively, obtained from 11 X-ray irradiation dose-points (0, 0.05, 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, and 5 Gy). The dose-response relationship followed a linear-quadratic equation, Y=C+αD+βD², with the coefficients C=0.0011 for DC and 0.0015 for TR, α=0.0119 for DC and 0.0048 for TR, and β=0.0617 for DC and 0.0237 for TR. Correlation coefficients between irradiation doses and chromosomal aberrations were 0.971 for DC and 0.6 for TR, indicating a very strong and a moderate correlation, respectively. This is the first study implementing cytogenetic dosimetry following exposure to ionizing X-radiation.

Digital object identifier (DOI): 10.3343/alm.2019.39.1.91

BMC plant biology, 19, 183
2019

Development and characterisation of interspecific hybrid lines with genome-wide introgressions from Triticum timopheevii in a hexaploid wheat background.

Devi, Urmila, Grewal, Surbhi, Yang, Cai-Yun, Hubbart-Edwards, Stella, Scholefield, Duncan, Ashling, Stephen, Burridge, Amanda, King, Ian P, King, Julie

Triticum timopheevii (2n = 4x = 28; A A GG), is an important source for new genetic variation for wheat improvement with genes for potential disease resistance and salt tolerance. By generating a range of interspecific hybrid lines, T. timopheevii can contribute to wheat's narrow gene-pool and be practically utilised in wheat breeding programmes. Previous studies that have generated such introgression lines between wheat and its wild relatives have been unable to use high-throughput methods to detect the presence of wild relative segments in such lines. A whole genome introgression approach, exploiting homoeologous recombination in the absence of the Ph1 locus, has resulted in the transfer of different chromosome segments from both the A and G genomes of T. timopheevii into wheat. These introgressions have been detected and characterised using single nucleotide polymorphism (SNP) markers present on a high-throughput Axiom® Genotyping Array. The analysis of these interspecific hybrid lines has resulted in the detection of 276 putative unique introgressions from T. timopheevii, thereby allowing the generation of a genetic map of T. timopheevii containing 1582 SNP markers, spread across 14 linkage groups representing each of the seven chromosomes of the A and G genomes of T. timopheevii. The genotyping of the hybrid lines was validated through fluorescence in situ hybridisation (FISH). Comparative analysis of the genetic map of T. timopheevii and the physical map of the hexaploid wheat genome showed that synteny between the two species is highly conserved at the macro-level and confirmed the presence of inter- and intra-genomic translocations within the A and G genomes of T. timopheevii that have been previously only detected through cytological techniques. In this work, we report a set of SNP markers present on a high-throughput genotyping array, able to detect the presence of T. timopheevii in a hexaploid wheat background making it a potentially valuable tool for marker assisted selection (MAS) in wheat pre-breeding programs. These valuable resources of high-density molecular markers and wheat-T. timopheevii hybrid lines will greatly enhance the work being undertaken for wheat improvement through wild relative introgressions.

Digital object identifier (DOI): 10.1186/s12870-019-1785-z

Chemosphere, 215, 703--709
2019

Nanomaterials induce DNA-protein crosslink and DNA oxidation: A mechanistic study with RTG-2 fish cell line and Comet assay modifications.

Klingelfus, T, Disner, G R, Voigt, C L, Alle, L F, Cestari, M M, Leme, D M

Genotoxic effects of nanomaterials (NMs) have been controversially reported in literature, and the mode of action (MoA) via DNA oxidation is cited as the main damage caused by them. Evidence of nano-silver as a crosslinker has been previously reported by the present research team in an in vivo fish genotoxicity study. Thus, aiming to confirm the evidence about NMs as crosslinker agent, the present investigation elucidated the genotoxic potential of NMs and their genotoxic MoA through in vitro assay with RTG-2 cells line (rainbow trout gonadal) by exposure to nano-silver (PVP-coated) and nano-titanium. The types and levels of DNA damage were assessed by the Comet assay (standard alkaline, hOGG1-modified alkaline, and two crosslink-modified alkaline versions). It was demonstrated that the use of the standard alkaline Comet assay alone may inaccurately predict the genotoxicity of NMs since oxidative and crosslink DNA damages were also verified in RTG-2 cells when assessed by the modified versions of the alkaline protocol. More importantly, it was confirmed that both nano-silver and nano-titanium acted as DNA-protein crosslinkers through the Comet assay version with proteinase K. As both nano-silver and nano-titanium present a great risk to aquatic life, these findings reinforce the need of genotoxicity testing strategies that encompass the assessment of different types of DNA damage, in order to ensure an accurate prediction of the genotoxic potential of NMs.

Digital object identifier (DOI): 10.1016/j.chemosphere.2018.10.118

Journal of applied genetics, 60, 63--70
2019

Structural and copy number chromosome abnormalities in canine cutaneous mast cell tumours.

Vozdova, Miluse, Kubickova, Svatava, Cernohorska, Halina, Fröhlich, Jan, Fictum, Petr, Rubes, Jiri

Mast cell tumours (MCTs) are the most common skin tumours in dogs. Their clinical behaviour is variable and their aetiology remains largely unknown. We performed a metaphase fluorescence in situ hybridisation (FISH) with whole chromosome painting probes, and interphase FISH with BAC probes for 14 cancer-related genes to reveal clonal structural chromosome rearrangements and copy number variants (CNVs) in canine cutaneous MCTs. The metaphase FISH performed in three MCTs revealed several clonal monosomies and trisomies and two different chromosome rearrangements. No centric fusions were detected. The interphase FISH showed a variety of low frequency CNVs for the individual cancer-related genes. The heterogeneous character of the detected abnormalities indicates increased chromosome instability in canine MCTs. The clonal gain of chromosome 11 was detected in 81% (13/16) of the MCTs. Further research is needed to evaluate the significance of this abnormality as prognostic factor for the survival time or recurrence risk assessments in canine cutaneous MCTs.

Digital object identifier (DOI): 10.1007/s13353-018-0471-4

Microbiological research, 221, 28--35
2019

Muscodor brasiliensis sp. nov. produces volatile organic compounds with activity against Penicillium digitatum.

Pena, Lorena C, Jungklaus, Gustavo H, Savi, Daiani C, Ferreira-Maba, Lisandra, Servienski, André, Maia, Beatriz H L N S, Annies, Vinicius, Galli-Terasawa, Lygia V, Glienke, Chirlei, Kava, Vanessa

Endophytic fungi belonging to Muscodor genus are considered as promising alternatives to be used in biological control due to the production of volatile organic compounds (VOCs). The strains LGMF1255 and LGMF1256 were isolated from the medicinal plant Schinus terebinthifolius and, by morphological data and phylogenetic analysis, identified as belonging to Muscodor genus. Phylogenetic analysis suggests that strain LGMF1256 is a new species, which is herein introduced as Muscodor brasiliensis sp. nov. The analysis of VOCs production revealed that compounds phenylethyl alcohol, α-curcumene, and E (β) farnesene until now has been reported only from M. brasiliensis, data that supports the classification of strain LGMF1256 as a new species. M. brasiliensis completely inhibited the phytopathogen P. digitatum in vitro. We also evaluated the ability of VOCs from LGMF1256 to inhibit the development of green mold symptoms by inoculation of P. digitatum in detached oranges. M. brasiliensis reduced the severity of diseases in 77%, and showed potential to be used for fruits storage and transportation to prevent the green mold symptoms development, eventually reducing the use of fungicides.

Digital object identifier (DOI): 10.1016/j.micres.2019.01.002

Cell death \& disease, 10, 186
2019

Type 3 inositol 1,4,5-trisphosphate receptor has antiapoptotic and proliferative role in cancer cells.

Rezuchova, Ingeborg, Hudecova, Sona, Soltysova, Andrea, Matuskova, Miroslava, Durinikova, Erika, Chovancova, Barbora, Zuzcak, Michal, Cihova, Marina, Burikova, Monika, Penesova, Adela, Lencesova, Lubomira, Breza, Jan, Krizanova, Olga

Although the involvement of type 1 (IP R1) and type 2 (IP R2) inositol 1,4,5-trisphosphate receptors in apoptosis induction has been well documented in different cancer cells and tissues, the function of type 3 IP R (IP R3) is still elusive. Therefore, in this work we focused on the role of IP R3 in tumor cells in vitro and in vivo. We determined increased expression of this receptor in clear cell renal cell carcinoma compared to matched unaffected part of the kidney from the same patient. Thus, we hypothesized about different functions of IP R3 compared to IP R1 and IP R2 in tumor cells. Silencing of IP R1 prevented apoptosis induction in colorectal cancer DLD1 cells, ovarian cancer A2780 cells, and clear cell renal cell carcinoma RCC4 cells, compared to apoptosis in cells treated with scrambled siRNA. As expected, silencing of IP R3 and subsequent apoptosis induction resulted in increased levels of apoptosis in all these cells. Further, we prepared a DLD1/IP R3_del cell line using CRISPR/Cas9 gene editing method. These cells were injected into nude mice and tumor's volume was compared with tumors induced by DLD1 cells. Lower volume of tumors originated from DLD1/IP R3_del cells was observed after 12 days, compared to wild type DLD1 cells. Also, the migration of these cells was lesser compared to wild type DLD1 cells. Apoptosis under hypoxic conditions was more pronounced in DLD1/IP R3_del cells than in DLD1 cells. These results clearly show that IP R3 has proliferative and anti-apoptotic effect in tumor cells, on contrary to the pro-apoptotic effect of IP R1.

Digital object identifier (DOI): 10.1038/s41419-019-1433-4

The journal of pathology. Clinical research, 5, 63--78
2019

Combined epithelial marker analysis of tumour budding in stage II colorectal cancer.

Slik, Khadija, Blom, Sami, Turkki, Riku, Välimäki, Katja, Kurki, Samu, Mustonen, Harri, Haglund, Caj, Carpén, Olli, Kallioniemi, Olli, Korkeila, Eija, Sundström, Jari, Pellinen, Teijo

Tumour budding predicts survival of stage II colorectal cancer (CRC) and has been suggested to be associated with epithelial-to-mesenchymal transition (EMT). However, the underlying molecular changes of tumour budding remain poorly understood. Here, we performed multiplex immunohistochemistry (mIHC) to phenotypically profile tumours using known EMT-associated markers: E-cadherin (adherence junctions), integrin β4 (ITGB4; basement membrane), ZO-1 (tight junctions), and pan-cytokeratin. A subpopulation of patients showed high ITGB4 expression in tumour buds, and this coincided with a switch of ITGB4 localisation from the basal membrane of intact epithelium to the cytoplasm of budding cells. Digital image analysis demonstrated that tumour budding with high ITGB4 expression in tissue microarray (TMA) cores correlated with tumour budding assessed from haematoxylin and eosin (H&E) whole sections and independently predicted poor disease-specific survival in two independent stage II CRC cohorts (hazard ratio [HR] = 4.50 (95% confidence interval [CI] = 1.50-13.5), n = 232; HR = 3.52 (95% CI = 1.30-9.53), n = 72). Furthermore, digitally obtained ITGB4-high bud count in random TMA cores was better associated with survival outcome than visual tumour bud count in corresponding H&E-stained samples. In summary, the mIHC-based phenotypic profiling of human tumour tissue shows strong potential for the molecular characterisation of tumour biology and for the discovery of novel prognostic biomarkers.

Digital object identifier (DOI): 10.1002/cjp2.119

Journal of clinical microbiology, 56
2018

Automated Interpretation of Blood Culture Gram Stains by Use of a Deep Convolutional Neural Network.

Smith, Kenneth P, Kang, Anthony D, Kirby, James E

Microscopic interpretation of stained smears is one of the most operator-dependent and time-intensive activities in the clinical microbiology laboratory. Here, we investigated application of an automated image acquisition and convolutional neural network (CNN)-based approach for automated Gram stain classification. Using an automated microscopy platform, uncoverslipped slides were scanned with a 40× dry objective, generating images of sufficient resolution for interpretation. We collected 25,488 images from positive blood culture Gram stains prepared during routine clinical workup. These images were used to generate 100,213 crops containing Gram-positive cocci in clusters, Gram-positive cocci in chains/pairs, Gram-negative rods, or background (no cells). These categories were targeted for proof-of-concept development as they are associated with the majority of bloodstream infections. Our CNN model achieved a classification accuracy of 94.9% on a test set of image crops. Receiver operating characteristic (ROC) curve analysis indicated a robust ability to differentiate between categories with an area under the curve of >0.98 for each. After training and validation, we applied the classification algorithm to new images collected from 189 whole slides without human intervention. Sensitivity and specificity were 98.4% and 75.0% for Gram-positive cocci in chains and pairs, 93.2% and 97.2% for Gram-positive cocci in clusters, and 96.3% and 98.1% for Gram-negative rods. Taken together, our data support a proof of concept for a fully automated classification methodology for blood-culture Gram stains. Importantly, the algorithm was highly adept at identifying image crops with organisms and could be used to present prescreened, classified crops to technologists to accelerate smear review. This concept could potentially be extended to all Gram stain interpretive activities in the clinical laboratory.

Digital object identifier (DOI): 10.1128/JCM.01521-17

PloS one, 13, e0193213
2018

Impact of 9p deletion and p16, Cyclin D1, and Myc hyperexpression on the outcome of anaplastic oligodendrogliomas.

Michaud, Karine, de Tayrac, Marie, D'Astous, Myreille, Paquet, Claudie, Gould, Peter Vincent, Saikali, Stéphan

To study the presence of 9p deletion and p16, cyclin D1 and Myc expression and their respective diagnostic and prognostic interest in oligodendrogliomas. We analyzed a retrospective series of 40 consecutive anaplastic oligodendrogliomas (OIII) from a single institution and compared them to a control series of 10 low grade oligodendrogliomas (OII). Automated FISH analysis of chromosome 9p status and immunohistochemistry for p16, cyclin D1 and Myc was performed for all cases and correlated with clinical and histological data, event free survival (EFS) and overall survival (OS). Chromosome 9p deletion was observed in 55% of OIII (22/40) but not in OII. Deletion was highly correlated to EFS (median = 29 versus 53 months, p<0.0001) and OS (median = 48 versus 83 months, p<0.0001) in both the total cohort and the OIII population. In 9p non-deleted oligodendrogliomas, p16 hyperexpression correlated with a shorter OS (p = 0.02 in OII and p = 0.0001 in OIII) whereas lack of p16 expression was correlated to a shorter EFS and OS in 9p deleted OIII (p = 0.001 and p = 0.0002 respectively). Expression of Cyclin D1 was significantly higher in OIII (median expression 45% versus 14% for OII, p = 0.0006) and was correlated with MIB-1 expression (p<0.0001), vascular proliferation (p = 0.002), tumor necrosis (p = 0.04) and a shorter EFS in the total cohort (p = 0.05). Hyperexpression of Myc was correlated to grade (median expression 27% in OII versus 35% in OIII, p = 0.03), and to a shorter EFS in 9p non-deleted OIII (p = 0.01). Chromosome 9p deletion identifies a subset of OIII with significantly worse prognosis. The combination of 9p status and p16 expression level identifies two distinct OIII populations with divergent prognosis. Hyperexpression of Bcl1 and Myc appears highly linked to anaplasia but the prognostic value is unclear and should be investigated further.

Digital object identifier (DOI): 10.1371/journal.pone.0193213

Environmental science and pollution research international
2018

Toxicological evaluation of nail polish waste discarded in the environment.

Felzenszwalb, Israel, Fernandes, Andreia da Silva, Brito, Lara Barroso, Oliveira, Gisele Augusto Rodrigues, Silva, Paula Aquino Soeiro, Arcanjo, Maria Elena, Marques, Monica Regina da Costa, Vicari, Taynah, Leme, Daniela Morais, Cestari, Marta Margarete, Ferraz, Elisa Raquel Anastacio

Nail polish has been widely used around the world. However, the hazards of nail polishes discarded in the environment are still poorly investigated. Thus, the toxicogenetic effects of solubilized (SE) and leached (LE) extracts from nail polishes were investigated, simulating their disposal on water and landfill, respectively, and identifying their physicochemical properties and chemical constituents. Organic compounds and metals were detected in both extracts. SE and LE only induced mutagenic effects in TA98 Salmonella strain in the presence and absence of exogenous metabolic activation. Although both extracts did not significantly increase the frequency of micronucleated HepG2 cells, the cell viability was affected by 24-h exposure. No DNA damage was observed in gonad fish cells (RTG-2) exposed to both extracts; however, the highest SE and LE concentrations induced significant lethal and sublethal effects on zebrafish early-life stages during 96-h exposure. Based on our findings, it can be concluded that if nail polishes enter aquatic systems, it may cause negative impacts to the environment.

Digital object identifier (DOI): 10.1007/s11356-018-1880-y

Journal of medical entomology, 55, 575--586
2018

Description of Larval Instars To Fill a Gap in Forensic Entomology: The Larvae of Paralucilia pseudolyrcea (Diptera: Calliphoridae).

Da Silva, S M, Vairo, K P, Moura, M O

A fundamental assumption of forensic entomology for estimating the postmortem interval is that insect species are accurately identified, which depends on diagnostic morphological characters. Larvae of the blow fly Paralucilia pseudolyrcea (Mello, 1969) (Diptera: Calliphoridae) were sampled from four corpses in the state of Paraná, Brazil, but despite the forensic importance of this species, morphological data for the identification of its larval instars are lacking, limiting its usefulness in such cases. Thus, the main goal of this study was to describe the larval instars of P. pseudolyrcea. The material was obtained from a colony established by larvae collected from a corpse of a murder case. Overall, the distribution of spines is a key character for identifying this species in the first, second and third instars. Other characteristics, such as the presence of an accessory oral sclerite, the small cirri, the number of lobes of the anterior spiracle and the morphology of posterior spiracles, separates P. pseudolyrcea from other necrophagous blow flies. The detailed morphological description provided here facilitates the identification of larval instars of P. pseudolyrcea and their differentiation from those of other calliphorid species.

Digital object identifier (DOI): 10.1093/jme/tjx257

Journal of Pathology Informatics, 9(1), 13
2018

Constant quest for quality: Digital cytopathology

Van Es, Simone L., Greaves, Janelle, Gay, Stephanie, Ross, Jennifer, Holzhauser, Derek, Badrick, Tony

Background: Special consideration should be given when creating and selecting cytopathology specimens for digitization to maximize quality. Advances in scanning and viewing technology can also improve whole-slide imaging (WSI) output quality. Methods: Accumulated laboratory experience with digitization of glass cytopathology slides was collected. Results: This paper describes characteristics of a cytopathology glass slide that can reduce quality on resulting WSI. Important points in the glass cytopathology slide selection process, preparation, scanning, and WSI-editing process that will maximize the quality of the resulting acquired digital image are covered. The paper outlines scanning solutions which have potential to predict issues with a glass cytopathology slide before image acquisition, allowing for adjustment of the scanning approach. WSI viewing solutions that better simulate the traditional microscope experience are also discussed. Conclusion: In addition to taking advantage of technical advances, practical steps can taken to maximize quality of cytopathology WSI.

Digital object identifier (DOI): 10.4103/jpi.jpi_6_18

Biological procedures online, 20, 13
2018

Optimization of Immunofluorescent Detection of Bone Marrow Disseminated Tumor Cells.

Axelrod, Haley D, Pienta, Kenneth J, Valkenburg, Kenneth C

Cancer metastasis is the primary cause of cancer-related deaths and remains incurable. Current clinical methods for predicting metastatic recurrence are not sensitive enough to detect individual cancer cells in the body; therefore, current efforts are directed toward liquid biopsy-based assays to capture circulating and disseminated tumor cells (CTCs and DTCs) in the blood and bone marrow, respectively. The most promising strategy is fluorescence-based immunostaining using cancer cell-specific markers. However, despite recent efforts to develop robust processing and staining platforms, results from these platforms have been discordant among groups, particularly for DTC detection. While the choice of cancer cell-specific markers is a large factor in this discordance, we have found that marker-independent factors causing false signal are just as critical to consider. Bone marrow is particularly challenging to analyze by immunostaining because endogenous immune cell properties and bone marrow matrix components typically generate false staining. For immunostaining of whole tumor tissue containing ample cancer cells, this background staining can be overcome. Application of fluorescent-based staining for rare cells, however, is easily jeopardized by immune cells and autofluorescence that lead to false signal. We have specifically found two types of background staining in bone marrow samples: autofluorescence of the tissue and non-specific binding of secondary antibodies. We systematically optimized a basic immunofluorescence protocol to eliminate this background using cancer cells spiked into human bone marrow. This enhanced the specificity of automated scanning detection software. Our optimized protocol also outperformed a commercial rare cell detection protocol in detecting candidate DTCs from metastatic patient bone marrow. Robust optimization to increase the signal-to-noise ratio of immunofluorescent staining of bone marrow is required in order to achieve the necessary sensitivity and specificity for rare cell detection. Background immunofluorescent staining in bone marrow causes uncertainty and inconsistency among investigators, which can be overcome by systematically addressing each contributing source. Our optimized assay eliminates sources of background signal, and is adaptable to automated staining platforms for high throughput analysis.

Digital object identifier (DOI): 10.1186/s12575-018-0078-5

Cancers, 10, e0193213
2018

The Transition between Telomerase and ALT Mechanisms in Hodgkin Lymphoma and Its Predictive Value in Clinical Outcomes.

M'kacher, Radhia, Cuceu, Corina, Al Jawhari, Mustafa, Morat, Luc, Frenzel, Monika, Shim, Grace, Lenain, Aude, Hempel, William M, Junker, Steffen, Girinsky, Theodore, Colicchio, Bruno, Dieterlen, Alain, Heidingsfelder, Leonhard, Borie, Claire, Oudrhiri, Noufissa, Bennaceur-Griscelli, Annelise, Moralès, Olivier, Renaud, Sarah, Van de Wyngaert, Zoé, Jeandidier, Eric, Delhem, Nadira, Carde, Patrice

: We analyzed telomere maintenance mechanisms (TMMs) in lymph node samples from HL patients treated with standard therapy. The TMMs correlated with clinical outcomes of patients. : Lymph node biopsies obtained from 38 HL patients and 24 patients with lymphadenitis were included in this study. Seven HL cell lines were used as in vitro models. Telomerase activity (TA) was assessed by TRAP assay and verified through hTERT immunofluorescence expression; alternative telomere lengthening (ALT) was also assessed, along with EBV status. : Both TA and ALT mechanisms were present in HL lymph nodes. Our findings were reproduced in HL cell lines. The highest levels of TA were expressed in CD30-/CD15- cells. Small cells were identified with ALT and TA. Hodgkin and Reed Sternberg cells contained high levels of PML bodies, but had very low hTERT expression. There was a significant correlation between overall survival ( < 10 ), event-free survival ( < 10 ), and freedom from progression ( < 10 ) and the presence of an ALT profile in lymph nodes of EBV+ patients. : The presence of both types of TMMs in HL lymph nodes and in HL cell lines has not previously been reported. TMMs correlate with the treatment outcome of EBV+ HL patients.

Digital object identifier (DOI): 10.3390/cancers10060169

Radiation protection dosimetry, 182, 139--145
2018

DEVELOPMENT OF A MINIATURIZED VERSION OF DICENTRIC CHROMOSOME ASSAY TOOL FOR RADIOLOGICAL TRIAGE.

Balajee, Adayabalam S, Smith, Tammy, Ryan, Terri, Escalona, Maria, Dainiak, Nicholas

Use of ionizing radiation (IR) in various industrial, medical and other applications can potentially increase the risk of medical, occupational or accidental human exposure. Additionally, in the event of a radiological or nuclear (R/N) incident, several tens of hundreds and thousands of people are likely to be exposed to IR. IR causes serious health effects including mortality from acute radiation syndrome and therefore it is imperative to determine the absorbed radiation dose, which will enable physicians in making an appropriate clinical 'life-saving' decision. The 'Dicentric Chromosome Assay (DCA)' is the gold standard for estimating the absorbed radiation dose but its performance is time consuming and laborious. Further, timely evaluation of dicentric chromosomes (DCs) for dose estimation in a large number of samples provides a bottleneck because of a limited number of trained personnel and a prolonged time for manual analysis. To circumvent some of these technical issues, we developed and optimized a miniaturized high throughput version of DCA (mini-DCA) in a 96-microtube matrix with bar-coded 1.4 ml tubes to enable the processing of a large number of samples. To increase the speed of DC analysis for radiation dose estimation, a semi-automated scoring was optimized using the Metafer DCScore algorithm. The accuracy of mini-DCA in dose estimation was verified and validated though comparison with conventional DCA performed in 15 ml conical tubes. The mini-DCA considerably reduced the sample processing time by a factor of 4 when compared to the conventional DCA. Further, the radiation doses estimated by mini-DCA using the triage mode of scoring (50 cells or 30 DCs) were similar to that of conventional DCA using 300-500 cells. The mini-DCA coupled with semi-automated DC scoring not only reduced the sample processing and analysis times by a factor of 4 but also enabled the processing of a large number of samples at once. Our mini-DCA method, once automated for high throughput robotic platforms, will be an effective radiological triage tool for mass casualty incidents.

Digital object identifier (DOI): 10.1093/rpd/ncy127

Radiology, 288, 529--535
2018

Abdominopelvic 1.5-T and 3.0-T MR Imaging in Healthy Volunteers: Relationship to Formation of DNA Double-Strand Breaks.

Suntharalingam, Saravanabavaan, Mladenov, Emil, Sarabhai, Theresia, Wetter, Axel, Kraff, Oliver, Quick, Harald H, Forsting, Michael, Iliakis, Georg, Nassenstein, Kai

Purpose To investigate the relationship between abdominopelvic magnetic resonance (MR) imaging and formation of DNA double-strand breaks (DSBs) in peripheral blood lymphocytes among a cohort of healthy volunteers. Materials and Methods Blood samples were obtained from 40 healthy volunteers (23 women and 17 men; mean age, 27.2 years [range, 21-37 years]) directly before and 5 and 30 minutes after abdominopelvic MR imaging performed at 1.5 T (n = 20) or 3.0 T (n = 20). The number of DNA DSBs in isolated blood lymphocytes was quantified after indirect immunofluorescent staining of a generally accepted DSB marker, ?-H2AX, by means of high-throughput automated microscopy. As a positive control of DSB induction, blood lymphocytes from six volunteers were irradiated in vitro with x-rays at a dose of 1 Gy (70-90 keV). Statistical analysis was performed by using a Friedman test. Results No significant alteration in the frequency of DNA DSB induction was observed after MR imaging (before imaging: 0.22 foci per cell, interquartile range [IQR] = 0.54 foci per cell; 5 minutes after MR imaging: 0.08 foci per cell, IQR = 0.39 foci per cell; 30 minutes after MR imaging: 0.09 foci per cell, IQR = 0.63 foci per cell; P = .057). In vitro radiation of lymphocytes with 1 Gy led to a significant increase in DSBs (0.22 vs 3.43 foci per cell; P = .0312). The frequency of DSBs did not differ between imaging at 1.5 T and at 3.0 T (5 minutes after MR imaging: 0.23 vs 0.06 foci per cell, respectively [P = .57]; 30 minutes after MR imaging: 0.12 vs 0.08 foci per cell [P = .76]). Conclusion Abdominopelvic MR imaging performed at 1.5 T or 3.0 T does not affect the formation of DNA DSBs in peripheral blood lymphocytes.

Digital object identifier (DOI): 10.1148/radiol.2018172453