scholarly journals Differential DNA methylation in somatic and sperm cells of hatchery vs wild (natural-origin) steelhead trout populations

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Eric Nilsson ◽  
Ingrid Sadler-Riggleman ◽  
Daniel Beck ◽  
Michael K Skinner
Keyword(s):  
Dna Methylation ◽  
Slow Growth ◽  
Copy Number Variations ◽  
Fast Growth ◽  
Future Generations ◽  
Steelhead Trout ◽  
Evolutionary Trajectory ◽  
Natural Origin ◽  
Epigenetic Programming ◽  
Maturation Rate

Abstract Environmental factors such as nutrition, stress, and toxicants can influence epigenetic programming and phenotypes of a wide variety of species from plants to humans. The current study was designed to investigate the impacts of hatchery spawning and rearing on steelhead trout (Oncorhynchus mykiss) vs the wild fish on a molecular level. Additionally, epigenetic differences between feeding practices that allow slow growth (2 years) and fast growth (1 year) hatchery trout were investigated. The sperm and red blood cells (RBC) from adult male slow growth/maturation hatchery steelhead, fast growth/maturation hatchery steelhead, and wild (natural-origin) steelhead were collected for DNA preparation to investigate potential alterations in differential DNA methylation regions (DMRs) and genetic mutations, involving copy number variations (CNVs). The sperm and RBC DNA both had a large number of DMRs when comparing the hatchery vs wild steelhead trout populations. The DMRs were cell type specific with negligible overlap. Slow growth/maturation compared to fast growth/maturation steelhead also had a larger number of DMRs in the RBC samples. A number of the DMRs had associated genes that were correlated to various biological processes and pathologies. Observations demonstrate a major epigenetic programming difference between the hatchery and wild natural-origin fish populations, but negligible genetic differences. Therefore, hatchery conditions and growth/maturation rate can alter the epigenetic developmental programming of the steelhead trout. Interestingly, epigenetic alterations in the sperm allow for potential epigenetic transgenerational inheritance of phenotypic variation to future generations. The impacts of hatchery exposures are not only important to consider on the fish exposed, but also on future generations and evolutionary trajectory of fish in the river populations.

Variation in xylem anatomy of selected populations of lodgepole pine

2001 ◽  
Vol 31 (11) ◽  
pp. 2049-2057 ◽  
Author(s):  
Tongli Wang ◽  
Sally N Aitken
Keyword(s):  
Cell Wall ◽  
Wall Thickness ◽  
Slow Growth ◽  
Lodgepole Pine ◽  
High Density ◽  
Cell Wall Thickness ◽  
Fast Growth ◽  
Low Density ◽  
Xylem Anatomy ◽  
Latewood Density

Variation in xylem anatomy among selected populations of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) was examined using digital image analysis based on an annual growth ring (age 10) per tree. Four subpopulations were selected using the following criteria for height growth and wood density: (i) fast growth and high density; (ii) slow growth and high density; (iii) fast growth and low density; and (iv) slow growth and low density. Significant differences were found among subpopulations for several anatomical parameters including tracheid density, lumen size, and cell wall thickness that may affect the economic value and utilization of wood. Principal component analysis indicate that the first four principal components (PCs) were associated with (i) ring area (PC1), (ii) earlywood density (PC2), (iii) latewood density (PC3), and (iv) lumen shape in earlywood (PC4), suggesting that these aspects of wood properties and growth are controlled by different sets of genes. Relative contributions of total number of tracheids, tracheid lumen size, and cell wall thickness to ring area and correlations between cell wall area proportion and X-ray density are discussed.

PATH-39. INTEGRATED MOLECULAR-MORPHOLOGICAL MENINGIOMA CLASSIFICATION: A MULTICENTER RETROSPECTIVE ANALYSIS, RETRO- AND PROSPECTIVELY VALIDATED

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi123-vi124
Author(s):  
Sybren Maas ◽  
Damian Stichel ◽  
Thomas Hielscher ◽  
Philipp Sievers ◽  
Anna Berghoff ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Copy Number ◽  
Retrospective Cohort ◽  
Clinical Decision Making ◽  
Clinical Decision ◽  
Molecular Data ◽  
Copy Number Variations ◽  
Who Grade ◽  
Risk Of Progression ◽  
The Individual

Abstract PURPOSE Meningiomas are the most frequent primary intracranial tumors. Patient outcome varies widely from cases with benign to highly aggressive, ultimately fatal courses. Reliable identification of risk of progression for the individual patient is of pivotal importance in clinical management. However, only biomarkers for highly aggressive tumors are established at present (CDKN2A/B and TERT), while no molecularly-based stratification exists for the broad spectrum of low- and intermediate-risk meningioma patients. PATIENTS AND METHODS DNA methylation data and copy-number information were generated for 3,031 meningiomas of 2,868 individual patients, with mutation data for 858 samples. DNA methylation subgroups, copy-number variations (CNV), mutations and WHO grading were comparatively analyzed. Prediction power for outcome of these parameters was assessed in an initial retrospective cohort of 514 patients, and validated on a retrospective cohort of 184, and on a prospective cohort of 287 multi-center cases, respectively. RESULTS Both CNV and methylation family- (MF)-based subgrouping independently resulted in an increase in prediction accuracy of risk of recurrence compared to the WHO classification (c-indexes WHO 2016, CNV, and MF 0.699, 0.706 and 0.721, respectively). Merging all independently powerful risk stratification approaches into an integrated molecular-morphological score resulted in a further, substantial increase in accuracy (c-index 0.744). This integrated score consistently provided superior accuracy in all three cohorts, significantly outperforming WHO grading (c-index difference p=0.005). Besides the overall stratification advantage, the integrated score separates more precisely for risk of progression at the diagnostically challenging interface of WHO grade 1 and grade 2 tumors (HR 4.56 [2.97;7.00], 4.34 [2.48;7.57] and 3.34 [1.28; 8.72] for discovery, retrospective, and prospective validation cohort, respectively). CONCLUSIONS Merging these layers of histological and molecular data into an integrated, three-tiered score significantly improves the precision in meningioma stratification. Implementation into diagnostic routine informs clinical decision-making for meningioma patients on the basis of robust outcome prediction.

scholarly journals Both Epimutations and Chromosome Aberrations Affect Multiple Imprinted Loci in Aggressive Wilms Tumors

Cancers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3411
Author(s):  
Laura Pignata ◽  
Orazio Palumbo ◽  
Flavia Cerrato ◽  
Basilia Acurzio ◽  
Enrique de Álava ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Chromosome Aberrations ◽  
Wilms Tumor ◽  
Tumor Stage ◽  
Copy Number Variations ◽  
Molecular Defect ◽  
Driver Genes ◽  
Cancer Driver ◽  
Aggressive Tumors ◽  
Methylation Defects

The embryonal renal cancer Wilms tumor (WT) accounts for 7% of all children’s malignancies. Its most frequent molecular defect is represented by DNA methylation abnormalities at the imprinted 11p15.5 region. Multiple imprinted methylation alterations dictated by chromosome copy-number variations have been recently demonstrated in adult cancers, raising the question of whether multiple imprinted loci were also affected in WT. To address this issue, we analyzed DNA methylation and chromosome profiles of 7 imprinted loci in 48 WT samples. The results demonstrated that methylation abnormalities of multiple imprinted loci occurred in 35% of the cases, but that they were associated with either chromosome aberrations or normal chromosome profiles. Multiple imprinted methylation changes were correlated with tumor stage and presence of metastasis, indicating that these epimutations were more frequent in highly aggressive tumors. When chromosome profiles were affected, these alterations were extended to flanking cancer driver genes. Overall, this study demonstrates the presence of multiple imprinted methylation defects in aggressive WTs and suggests that the mechanism by which they arise in embryonal and adult cancers is different.

scholarly journals Genetic selection for growth drives differences in intestinal microbiota composition and parasite disease resistance in gilthead sea bream

Microbiome ◽  
2020 ◽  
Vol 8 (1) ◽  
Author(s):  
M. Carla Piazzon ◽  
Fernando Naya-Català ◽  
Erick Perera ◽  
Oswaldo Palenzuela ◽  
Ariadna Sitjà-Bobadilla ◽  
...  
Keyword(s):  
Disease Resistance ◽  
Intestinal Microbiota ◽  
Slow Growth ◽  
Parasitic Infection ◽  
Fast Growth ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Microbial Composition ◽  
Bacterial Populations ◽  
Dietary Changes

Abstract Background The key effects of intestinal microbiota in animal health have led to an increasing interest in manipulating these bacterial populations to improve animal welfare. The aquaculture sector is no exception and in the last years, many studies have described these populations in different fish species. However, this is not an easy task, as intestinal microbiota is composed of very dynamic populations that are influenced by different factors, such as diet, environment, host age, and genetics. In the current study, we aimed to determine whether the genetic background of gilthead sea bream (Sparus aurata) influences the intestinal microbial composition, how these bacterial populations are modulated by dietary changes, and the effect of selection by growth on intestinal disease resistance. To that aim, three different groups of five families of gilthead sea bream that were selected during two generations for fast, intermediate, or slow growth (F3 generation) were kept together in the same open-flow tanks and fed a control or a well-balanced plant-based diet during 9 months. Six animals per family and dietary treatment were sacrificed and the adherent bacteria from the anterior intestinal portion were sequenced. In parallel, fish of the fast- and slow-growth groups were infected with the intestinal parasite Enteromyxum leei and the disease signs, prevalence, intensity, and parasite abundance were evaluated. Results No differences were detected in alpha diversity indexes among families, and the core bacterial architecture was the prototypical composition of gilthead sea bream intestinal microbiota, indicating no dysbiosis in any of the groups. The plant-based diet significantly changed the microbiota in the intermediate- and slow-growth families, with a much lower effect on the fast-growth group. Interestingly, the smaller changes detected in the fast-growth families potentially accounted for more changes at the metabolic level when compared with the other families. Upon parasitic infection, the fast-growth group showed significantly lower disease signs and parasite intensity and abundance than the slow-growth animals. Conclusions These results show a clear genome-metagenome interaction indicating that the fast-growth families harbor a microbiota that is more flexible upon dietary changes. These animals also showed a better ability to cope with intestinal infections.

scholarly journals Multigenerational and transgenerational impact of paternal bisphenol A exposure on male fertility in a mouse model

2020 ◽  
Vol 35 (8) ◽  
pp. 1740-1752 ◽  
Author(s):  
Md Saidur Rahman ◽  
Won-Ki Pang ◽  
Do-Yeal Ryu ◽  
Yoo-Jin Park ◽  
Myung-Geol Pang
Keyword(s):  
Dna Methylation ◽  
Bisphenol A ◽  
Large Scale ◽  
Corn Oil ◽  
Sperm Count ◽  
Future Generations ◽  
High Dose ◽  
Male Mice ◽  
Paternal Exposure ◽  
Methylation Patterns

Abstract STUDY QUESTION How does paternal exposure to bisphenol A (BPA) affect the fertility of male offspring in mice in future generations? SUMMARY ANSWER Paternal exposure to BPA adversely affects spermatogenesis, several important sperm functions and DNA methylation patterns in spermatozoa, which have both multigenerational (in F0 and F1) and partial transgenerational (mainly noticed in F2, but F3) impacts on the fertility of the offspring. WHAT IS KNOWN ALREADY BPA, a synthetic endocrine disruptor, is used extensively to manufacture polycarbonate plastics and epoxy resins. Growing evidence suggests that exposure to BPA during the developmental stages results in atypical reproductive phenotypes that could persist for generations to come. STUDY DESIGN, SIZE, DURATION CD-1 male mice (F0) were treated with BPA (5 or 50 mg/kg body weight per day (bw/day)) or ethinylestradiol (EE) (0.4 μg/kg bw/day) for 6 weeks. Control mice were treated with vehicle (corn oil) only. The treated male mice were bred with untreated female mice to produce first filial generation (F1 offspring). The F2 and F3 offspring were produced similarly, without further exposure to BPA. PARTICIPANTS/MATERIALS, SETTING, METHODS Histological changes in the testis along with functional, biochemical and epigenetic (DNA methylation) properties of spermatozoa were investigated. Subsequently, each parameter of the F0–F3 generations was compared between BPA-treated mice and control mice. MAIN RESULTS AND THE ROLE OF CHANCE Paternal BPA exposure disrupted spermatogenesis by decreasing the size and number of testicular seminiferous epithelial cells, which eventually led to a decline in the total sperm count of F0–F2 offspring (P < 0.05). We further showed that a high BPA dose decreased sperm motility in F0–F2 males by mediating the overproduction of reactive oxygen species (F0–F1) and decreasing intracellular ATP (F0–F2) in spermatozoa (P < 0.05). These changes in spermatozoa were associated with altered global DNA methylation patterns in the spermatozoa of F0–F3 males (P < 0.05). Furthermore, we noticed that BPA compromised sperm fertility in mice from the F0–F2 (in the both dose groups) and F3 generations (in the high-dose group only). The overall reproductive toxicity of BPA was equivalent to or higher (high dose) than that of the tested dose of EE. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Further research is required to determine the variables (e.g. lowest BPA dose) that are capable of producing changes in sperm function and fertility in future generations. WIDER IMPLICATIONS OF THE FINDINGS These results may shed light on how occupational exposure to BPA can affect offspring fertility in humans. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (Grant No. NRF-2018R1A6A1A03025159). M.S.R. was supported by Korea Research Fellowship Program through the NRF funded by the Ministry of Science and ICT (Grant No. 2017H1D3A1A02013844). There are no competing interests.

scholarly journals GENE-02. ESTABLISHING PERSONALIZED TREATMENT OPTIONS FOR RECURRENT HIGH-GRADE GLIOMAS

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi97-vi98
Author(s):  
Ann-Christin Hau ◽  
Linsey Houben ◽  
Eliane Klein ◽  
Anais Oudin ◽  
Daniel Stieber ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Drug Response ◽  
Treatment Strategies ◽  
Differential Sensitivity ◽  
Personalized Treatment ◽  
High Grade ◽  
Evolutionary Trajectory ◽  
Recurrent Tumors ◽  
Treatment Naïve ◽  
Tumor Organoids

Abstract BACKGROUND High grade glioma (HGG) patients develop resistance to standard treatment leading to disease progression and limited life expectancy. Recent advances in the molecular characterisation of treatment-naïve HGGs based on next generation sequencing and DNA methylation analyses have led to a better delineation of HGG-subtypes and identification of distinct genomic abnormalities opening opportunities for personalized treatment strategies. METHODS We collected 300 fresh glioma specimen with approximately 100 longitudinal samples of initial and recurrent tumors from 43 matched patients. We succeeded in generating a live-biobank of HGG patient-derived orthotopic xenografts (PDOX) and 3D tumor organoids that neatly recapitulates the mutational spectrum including structural DNA variations and methylation-based subtypes of gliomas. A highlight is the generation of 19 PDOXs of paired initial and relapse HGGs from 9 glioma patients, enabling high-throughput drug screens. We performed comprehensive molecular profiling using arrayCGH, DNA-methylation and targeted DNA sequencing on patient specimen and their derivatives, 3D tumor organoids and PDOXs. RESULTS Detailed analysis of the paired longitudinal samples indicated that PDOXs closely recapitulate the evolutionary trajectory of the parental tumors. Furthermore, targeted genomic sequencing of paired HGGs suggests that relapse tumors also accumulate somatic mutations in epigenetic effectors. Based on patient-derived material we carried out drug response screening on 3D tumor organoids using a compound library matching the majority of genes that were assessed with targeted sequencing. Differential drug responses between initial and recurrent tumors were observed and the prevailing primary drug response profiles were essentially recapitulad in the relapse setting. CONCLUSIONS Response assessment of treatment-naïve gliomas and their recurrences provides crucial information on the differential sensitivity between initial and relapsed HGGs and offers novel personalized therapeutic options for the relapse setting. Furthermore, in depth correlation of the profiled somatic molecular landscape with drug response will enable pharmacogenomic predictions of potential inhibitors in the clinical setting.

scholarly journals Copy number variations alter methylation and parallel IGF2 overexpression in adrenal tumors

2015 ◽  
Vol 22 (6) ◽  
pp. 953-967 ◽  
Author(s):  
Helene Myrtue Nielsen ◽  
Alexandre How-Kit ◽  
Carole Guerin ◽  
Frederic Castinetti ◽  
Hans Kristian Moen Vollan ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Copy Number ◽  
Methylation Status ◽  
Uniparental Disomy ◽  
Copy Number Variations ◽  
Conclusive Evidence ◽  
Adrenal Tumors ◽  
Benign Tumors ◽  
Parental Origin ◽  
Adrenocortical Carcinomas

Overexpression of insulin growth factor 2 (IGF2) is a hallmark of adrenocortical carcinomas and pheochromocytomas. Previous studies investigating the IGF2/H19 locus have mainly focused on a single molecular level such as genomic alterations or altered DNA methylation levels and the causal changes underlying IGF2 overexpression are still not fully established. In the current study, we analyzed 62 tumors of the adrenal gland from patients with Conn's adenoma (CA, n=12), pheochromocytomas (PCC, n=10), adrenocortical benign tumors (ACBT, n=20), and adrenocortical carcinomas (ACC, n=20). Gene expression, somatic copy number variation of chr11p15.5, and DNA methylation status of three differential methylated regions of the IGF2/H19 locus including the H19 imprinting control region were integratively analyzed. IGF2 overexpression was found in 85% of the ACCs and 100% of the PCCs compared to 23% observed in CAs and ACBTs. Copy number aberrations of chr11p15.5 were abundant in both PCCs and ACCs but while PCCs retained a diploid state, ACCs were frequently tetraploid (7/19). Loss of either a single allele or loss of two alleles of the same parental origin in tetraploid samples resulted in a uniparental disomy-like genotype. These copy number changes correlated with hypermethylation of the H19 ICR suggesting that the lost alleles were the unmethylated maternal alleles. Our data provide conclusive evidence that loss of the maternal allele correlates with IGF2 overexpression in adrenal tumors and that hypermethylation of the H19 ICR is a consequence thereof.

Effects of growth path, sire type, calving time and sex on growth and carcass characteristics of beef cattle in the agricultural area of Western Australia

2009 ◽  
Vol 49 (6) ◽  
pp. 504 ◽  
Author(s):  
B. L. McIntyre ◽  
G. D. Tudor ◽  
D. Read ◽  
W. Smart ◽  
T. J. Della Bosca ◽  
...  
Keyword(s):  
Slow Growth ◽  
Carcass Characteristics ◽  
Fast Growth ◽  
Carcass Weight ◽  
Breeding Value ◽  
Growth Path ◽  
High Quality ◽  
Fat Thickness ◽  
Estimated Breeding Value ◽  
The Imf

Growth, carcass characteristics and meat quality of the steer and heifer progeny of autumn (AC: March–April) and winter (WC: June–July) calving cows following weaning in January in each of 3 years (2003–05) were measured. The cows were mated to sires with a high estimated breeding value for either retail beef yield (RBY), intramuscular fat (IMF) or both RBY and IMF. After weaning, the progeny entered one of three growth paths until slaughter at an average steer liveweight of 500 kg: (i) fast – fast growth from weaning on a high concentrate feedlot diet; (ii) slow – slow growth from weaning (~0.6 kg/day) to 400 kg liveweight followed by growth at over 1 kg/day on high quality pasture; or (iii) comp. – 10% weaning weight loss, immediately after weaning followed by compensatory or rapid growth of over 1 kg/day on high quality pasture. Steers on the fast growth path had higher (P < 0.001) P8 fat thickness than those on the slow or comp. growth paths whereas heifers on the fast growth path only had higher (P < 0.001) P8 fat thickness than those on the slow growth path. Animals on the fast growth treatment had higher (P < 0.001) levels of IMF% than the slow animals which were higher (P < 0.001) than the comp. growth treatment. AUS-MEAT and US marbling scores were not different among growth paths. Animals finished on the fast growth path had a lower (P < 0.001) RBY% than those on either the slow or comp. growth paths. The RBY-sired progeny had higher (P < 0.001) finishing liveweight and hot standard carcass weight than either RBY and IMF or IMF-sired animals. IMF-sired progeny had higher (P < 0.01) rib fat thickness than either RBY or RBY- and IMF-sired animals. There was also a similar trend for P8 fat thickness but the effects were not significant. The RBY-sired animals had lower AUS-MEAT marbling scores (P < 0.01), US marbling scores (P < 0.001) and levels of IMF% (P < 0.01) than either of the other two sire treatments. RBY-sired animals also had higher (P < 0.001) estimated RBY% than those from the IMF sires while those by RBY and IMF sires were intermediate and not significantly different from either. Calving time had little influence on most carcass characteristics. However, WC animals tended to be fatter and have higher marbling scores than AC animals. The IMF% was higher (P < 0.01) in WC animals from RBY and IMF sires than in the corresponding AC animals. Heifers had lighter slaughter liveweight, carcass weight, were fatter and had higher marbling scores than steers. Heifers also had lower (P < 0.001) RBY% than the steers. Ossification scores for heifers were higher (P < 0.001) than for steers by ~30 units in AC calves and by 20 units in WC calves. The results of this experiment confirm the effectiveness of using sires with high estimated breeding value for the required characteristics in producing the desired improvements in the progeny. The absence of any interactions of sire type with growth path indicates that differences between sire types will be similar regardless of environmental conditions. Animals raised on a faster growth path after weaning produce carcasses with more fat and more IMF% than those grown on slower growth paths.

37 Effect of invivo and invitro heat stress on DNA methylation and DNA hydroxymethylation of bovine oocytes and embryos

2021 ◽  
Vol 33 (2) ◽  
pp. 126
Author(s):  
F. A. Diaz ◽  
E. J. Gutierrez ◽  
B. A. Foster ◽  
P. T. Hardin ◽  
K. R. Bondioli
Keyword(s):  
Dna Methylation ◽  
Heat Stress ◽  
Cleavage Rate ◽  
Cell Stage ◽  
Dna Hydroxymethylation ◽  
Early Embryos ◽  
Oocyte Collection ◽  
Maturation Rate ◽  
Bovine Oocytes ◽  
Fluorescence Immunohistochemistry

Reduced reproductive performance is one of the main effects caused by heat stress in cattle. Its negative effects have been observed at the transcriptional, biochemical, morphological, and developmental levels on the oocyte and embryo. There are no studies evaluating the effect of heat stress on the epigenetic profile of bovine oocytes and early embryos. The objective of this study was to evaluate the effect of invivo and invitro heat stress on DNA methylation and DNA hydroxymethylation in bovine MII oocytes, pronuclear, and 2- to 4-cell stage embryos. Seven Bos taurus crossbred nonpregnant, non-lactating beef cows located in Saint Gabriel, Louisiana (30.269746, −91.103357) were used for oocyte collection. Dominant follicle removal was performed 5 days before oocyte collection. Cumulus–oocyte complexes were collected by ovum pickup from follicles &gt;2mm. Samples were collected during the summer (August) and winter (February) (5 collections each). Three treatments were utilised: invivo heat stress (August samples), invitro heat stress (February samples subjected to 41°C during the first 12h of IVM and then to 38.5°C during the next 12h of IVM), and control (February samples IVM at 38.5°C). All oocytes collected per treatment were assigned to 3 developmental stages: MII oocytes, pronuclear, and 2- to 4-cell stage embryos. Embryos were obtained through standard IVF. DNA methylation and DNA hydroxymethylation was assessed by fluorescence immunohistochemistry utilising primary antibodies against 5′-methylcytosine and 5′-hydromethylcytosine and secondary antibodies Alexa Fluor 488 and Alexa Fluor 546, respectively. Samples were visualised with a fluorescence deconvolution microscope, and immunofluorescence data were expressed as corrected relative fluorescence per nucleus. Results were analysed by the Type III test of fixed effects and Tukey media separation utilising the Proc Glimmix of SAS 9.4 (P&lt;0.05). Maturation rate, 2 pronuclei (2PN) rate, cleavage rate, and 2- to 4-cell rate were analysed by Chi-square. There was no difference in maturation rate (88.19±7.57, 82.91±5.18, 94.51±5.04; P=0.2516), 2PN rate (79.34±10.23, 93.75±7.21, 81.74±12.53; P=0.1757), cleavage rate (79.26±2.69, 70.65±7.22, 81.85±16.65; P=0.2388) and 2- to 4-cell rate (69.38±7.83, 81.25±10.34, 61.11±11.69; P=0.4392) between invivo and invitro heat stress compared with control, respectively. No difference was found in DNA methylation (P=0.0537) or DNA hydroxymethylation (P=0.4632) between treatments in MII oocytes. When evaluating the paternal and maternal pronuclei, there was no difference in DNA methylation (P=0.9766; P=0.1954, respectively) or DNA hydroxymethylation (P=0.6440; P=0.1932, respectively) between invivo and invitro heat stress compared with control. Similarly, there was no difference in DNA methylation (P=0.0903) or DNA hydroxymethylation (P=0.2452) between treatments when evaluating the 2- to 4-cell embryos. In conclusion, we detected no effect of invivo or invitro heat stress on MII oocytes and early embryos when evaluating global DNA methylation and hydroxymethylation through fluorescence immunohistochemistry.

scholarly journals OS12.2 Targeting epigenetic pathways in the treatment of recurrent high-grade glioma

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii22-iii22
Author(s):  
A Hau ◽  
L Houben ◽  
E Klein ◽  
A Oudin ◽  
D Stieber ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Drug Response ◽  
High Grade Glioma ◽  
Differential Sensitivity ◽  
Targeted Sequencing ◽  
Patient Specific ◽  
Comparative Genomic ◽  
High Grade ◽  
Evolutionary Trajectory ◽  
Tumor Organoids

Abstract BACKGROUND High grade glioma (HGG) patients develop resistance to standard treatment leading to disease progression and limited life expectancy. Advances in the molecular characterisation of treatment-naïve HGGs based on next-generation sequencing and DNA methylation analyses have led to a better delineation of HGG subtypes and the identification of distinct genomic abnormalities. Furthermore, using large patient cohorts of longitudinal tumor samples, comprehensive genomic profiling studies emerged to investigate therapy-associated evolution of gliomas. All together, those studies point out the need for personalised treatment strategies, where applied drugs will be adapted to the unique patient-specific genetic abnormalities. MATERIAL AND METHODS We collected fresh samples of more than 800 brain tumors containing almost 300 glioma specimen with approximately 100 longitudinal samples of initial and recurrent tumors from 43 matched patients. By now, we have successfully established 34 patient-derived orthotopic xenografts (PDOXs) in mice. We performed comprehensive molecular profiling using array comparative genomic hybridisation, DNA methylation analysis and targeted DNA sequencing on patient specimen and their derivatives such as 3D tumor organoids and PDOXs. The custom-design sequencing panel comprises 234 genes that reflect both established genetic identifiers for individual glioma subtype classification and novel genes encoding mainly epigenetic effector genes. Based on patient-derived material we carried out drug response screening on 3D tumor organoids using a compound library matching the majority of genes that were assessed by targeted sequencing. RESULTS We succeeded in generating a live biobank of HGG patient-derived xenografts and 3D organoids that neatly recapitulates the mutational spectrum including structural DNA variation and methylation-based subtypes of gliomas. A highlight is the generation of 19 PDOXs of paired initial and relapse HGGs from a total of 9 glioma patients. A detailed analysis of the paired longitudinal samples indicated that PDOX models closely recapitulate the evolutionary trajectory of the parental tumors. Targeted sequencing of longitudinal HGG PDOXs suggests that relapse tumors accumulate somatic mutations in epigenetic effectors compared with the Initial. Differential drug responses between initial and relapse tumors were observed after screening of in vitro 3D tumor organoids. CONCLUSION Response assessment of naïve initial gliomas and recurrences provides crucial information on the differential sensitivity between initial and relapsed HGGs and offers novel personalised therapeutic options in the relapse setting. Furthermore, in depth correlation of the profiled somatic molecular landscape with drug response will enable pharmacogenomic predictions of potential inhibitors in the clinical setting.

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