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1.
PLoS One ; 19(1): e0296699, 2024.
Article in English | MEDLINE | ID: mdl-38232086

ABSTRACT

The cancer hazard associated with lifetime exposure to radiofrequency radiation (RFR) was examined in Sprague Dawley (SD) rats at the Ramazzini Institute (RI), Italy. There were increased incidences of gliomas and cardiac schwannomas. The translational relevance of these rare rat tumors for human disease is poorly understood. We examined the genetic alterations in RFR-derived rat tumors through molecular characterization of important cancer genes relevant for human gliomagenesis. A targeted next-generation sequencing (NGS) panel was designed for rats based on the top 23 orthologous human glioma-related genes. Single-nucleotide variants (SNVs) and small insertion and deletions (indels) were characterized in the rat gliomas and cardiac schwannomas. Translational relevance of these genetic alterations in rat tumors to human disease was determined through comparison with the Catalogue of Somatic Mutations in Cancer (COSMIC) database. These data suggest that rat gliomas resulting from life-time exposure to RFR histologically resemble low grade human gliomas but surprisingly no mutations were detected in rat gliomas that had homology to the human IDH1 p.R132 or IDH2 p.R172 suggesting that rat gliomas are primarily wild-type for IDH hotspot mutations implicated in human gliomas. The rat gliomas appear to share some genetic alterations with IDH1 wildtype human gliomas and rat cardiac schwannomas also harbor mutations in some of the queried cancer genes. These data demonstrate that targeted NGS panels based on tumor specific orthologous human cancer driver genes are an important tool to examine the translational relevance of rodent tumors resulting from chronic/life-time rodent bioassays.


Subject(s)
Brain Neoplasms , Glioma , Neurilemmoma , Radiation Exposure , Humans , Rats , Animals , Rats, Sprague-Dawley , Glioma/genetics , Glioma/pathology , Mutation , Neurilemmoma/genetics , High-Throughput Nucleotide Sequencing/methods , Isocitrate Dehydrogenase/genetics , Brain Neoplasms/pathology
2.
Toxicol Pathol ; 51(1-2): 39-55, 2023 01.
Article in English | MEDLINE | ID: mdl-37009983

ABSTRACT

Antimony trioxide (AT) is used as a flame retardant in fabrics and plastics. Occupational exposure in miners and smelters is mainly through inhalation and dermal contact. Chronic inhalation exposure to AT particulates in B6C3F1/N mice and Wistar Han rats resulted in increased incidences and tumor multiplicities of alveolar/bronchiolar carcinomas (ABCs). In this study, we demonstrated Kras (43%) and Egfr (46%) hotspot mutations in mouse lung tumors (n = 80) and only Egfr (50%) mutations in rat lung tumors (n = 26). Interestingly, there were no differences in the incidences of these mutations in ABCs from rats and mice at exposure concentrations that did and did not exceed the pulmonary overload threshold. There was increased expression of p44/42 mitogen-activated protein kinase (MAPK) (Erk1/2) protein in ABCs harboring mutations in Kras and/or Egfr, confirming the activation of MAPK signaling. Transcriptomic analysis indicated significant alterations in MAPK signaling such as ephrin receptor signaling and signaling by Rho-family GTPases in AT-exposed ABCs. In addition, there was significant overlap between transcriptomic data from mouse ABCs due to AT exposure and human pulmonary adenocarcinoma data. Collectively, these data suggest chronic AT exposure exacerbates MAPK signaling in ABCs and, thus, may be translationally relevant to human lung cancers.


Subject(s)
Adenocarcinoma, Bronchiolo-Alveolar , Lung Neoplasms , Mice , Rats , Humans , Animals , Proto-Oncogene Proteins p21(ras)/genetics , Adenocarcinoma, Bronchiolo-Alveolar/genetics , Adenocarcinoma, Bronchiolo-Alveolar/pathology , Mitogen-Activated Protein Kinases , Inhalation Exposure/adverse effects , Rats, Wistar , Mice, Inbred Strains , Lung Neoplasms/chemically induced , Lung Neoplasms/pathology , ErbB Receptors/genetics
3.
Appl Intell (Dordr) ; 53(12): 15909-15922, 2023.
Article in English | MEDLINE | ID: mdl-36466775

ABSTRACT

Domain adaptation is a potential method to train a powerful deep neural network across various datasets. More precisely, domain adaptation methods train the model on training data and test that model on a completely separate dataset. The adversarial-based adaptation method became popular among other domain adaptation methods. Relying on the idea of GAN, the adversarial-based domain adaptation tries to minimize the distribution between the training and testing dataset based on the adversarial learning process. We observe that the semi-supervised learning approach can combine with the adversarial-based method to solve the domain adaptation problem. In this paper, we propose an improved adversarial domain adaptation method called Semi-Supervised Adversarial Discriminative Domain Adaptation (SADDA), which can outperform other prior domain adaptation methods. We also show that SADDA has a wide range of applications and illustrate the promise of our method for image classification and sentiment classification problems.

4.
Heliyon ; 8(11): e11906, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36468114

ABSTRACT

This study investigates the moderating role of strategic interaction on the relationship between bank lending and macroeconomic factors, using panel data on Vietnamese commercial banks over 2008-2018. We find that the effect of macroeconomic and monetary policy shocks on bank lending behaviour is less pronounced when banks engage in a less competitively aggressive environment. The study contributes to the literature of bank lending by incorporating macroeconomic environment and micro (strategic interaction)-level to analyze the lending behaviour of an individual bank. Since the analysis of macroeconomic factors alone is insufficient to explain the aggregate relationships in the model of banking, understanding the nature of strategic interaction is essential to predetermine how bank lending behaviour relates to the transmission mechanism of monetary policy.

5.
Chemosphere ; 308(Pt 3): 136455, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36116626

ABSTRACT

Microplastic pollution is becoming a global challenge due to its long-term accumulation in the environment, causing adverse effects on human health and the ecosystem. Sludge discharged from wastewater treatment plants (WWTPs) plays a critical role as a carrier and primary source of environmental microplastic contamination. A significantly average microplastic variation between 1000 and 301,400 particles kg-1 has been reported in the sludge samples. In recent years, advanced technologies have been successfully applied to address this issue, including adsorption, advanced oxidation processes (AOPs), and membrane bioreactors (MBRs). Adsorption technologies are essential to utilizing novel adsorbents (e.g., biochar, graphene, zeolites) for effectively removing MPs. Especially, the removal efficiency of polymer microspheres from an aqueous solution by Mg/Zn modified magnetic biochars (Mg/Zn-MBC) was obtained at more than 95%. Also, advanced oxidation processes (AOPs) are widely applied to degrade microplastic contaminants, in which photocatalytic by semiconductors (e.g., TiO2 and ZnO) is a highly suitable approach to promote the degradation reactions owing to strongly hydroxyl radicals (OH*). Biological degradation-aided microorganisms (e.g., bacterial and fungal strains) have been reported to be suitable for removing microplastics. Yet, it was affected by biotic and abiotic factors of the environmental conditions (e.g., pH, light, temperature, moisture, bio-surfactants, microorganisms, enzymes) as well as their polymer characteristics, i.e., molecular weight, functional groups, and crystallinity. Notably, membrane bioreactors (MBRs) showed the highest efficiency in removing up to 99% microplastic particles and minimizing their contamination in sewage sludge. Further, MBRs illustrate the suitability for treating high-strength compounds, e.g., polymer debris and microplastic fibers from complex industrial wastewater. Finally, this study provided a comprehensive understanding of potential adverse risks, transportation pathways, and removal mechanisms of microplastic, which full-filled the knowledge gaps in this field.


Subject(s)
Graphite , Zeolites , Zinc Oxide , Ecosystem , Humans , Microplastics , Plastics , Sewage/chemistry , Surface-Active Agents , Wastewater/chemistry
6.
PLoS Negl Trop Dis ; 15(12): e0010029, 2021 12.
Article in English | MEDLINE | ID: mdl-34879060

ABSTRACT

Leprosy is the second most prevalent mycobacterial disease globally. Despite the existence of an effective therapy, leprosy incidence has consistently remained above 200,000 cases per year since 2010. Numerous host genetic factors have been identified for leprosy that contribute to the persistently high case numbers. In the past decade, genetic epidemiology approaches, including genome-wide association studies (GWAS), identified more than 30 loci contributing to leprosy susceptibility. However, GWAS loci commonly encompass multiple genes, which poses a challenge to define causal candidates for each locus. To address this problem, we hypothesized that genes contributing to leprosy susceptibility differ in their frequencies of rare protein-altering variants between cases and controls. Using deep resequencing we assessed protein-coding variants for 34 genes located in GWAS or linkage loci in 555 Vietnamese leprosy cases and 500 healthy controls. We observed 234 nonsynonymous mutations in the targeted genes. A significant depletion of protein-altering variants was detected for the IL18R1 and BCL10 genes in leprosy cases. The IL18R1 gene is clustered with IL18RAP and IL1RL1 in the leprosy GWAS locus on chromosome 2q12.1. Moreover, in a recent GWAS we identified an HLA-independent signal of association with leprosy on chromosome 6p21. Here, we report amino acid changes in the CDSN and PSORS1C2 genes depleted in leprosy cases, indicating them as candidate genes in the chromosome 6p21 locus. Our results show that deep resequencing can identify leprosy candidate susceptibility genes that had been missed by classic linkage and association approaches.


Subject(s)
Genetic Predisposition to Disease , Genome-Wide Association Study , Leprosy/genetics , Adolescent , Adult , B-Cell CLL-Lymphoma 10 Protein/genetics , Female , Genetic Linkage , High-Throughput Nucleotide Sequencing , Humans , Interleukin-18 Receptor alpha Subunit/genetics , Interleukin-18 Receptor beta Subunit/genetics , Male , Young Adult
7.
Arch Toxicol ; 95(10): 3171-3190, 2021 10.
Article in English | MEDLINE | ID: mdl-34468815

ABSTRACT

Rodent alveolar/bronchiolar carcinomas (ABC) that arise either spontaneously or due to chemical exposure are similar to a subtype of lung adenocarcinomas in humans. B6C3F1/N mice and F344/NTac rats exposed to cobalt metal dust (CMD) by inhalation developed ABCs in a dose dependent manner. In CMD-exposed mice, the incidence of Kras mutations in ABCs was 67% with 80% of those being G to T transversions on codon 12 suggesting a role of oxidative stress in the pathogenesis. In vitro studies, such as DMPO (5,5-dimethyl-1-pyrroline N-oxide) immune-spin trapping assay, and dihydroethidium (DHE) fluorescence assay on A549 and BEAS-2B cells demonstrated increased oxidative stress due to cobalt exposure. In addition, significantly increased 8-oxo-dG adducts were demonstrated by immunohistochemistry in lungs from mice exposed to CMD for 90 days. Furthermore, transcriptomic analysis on ABCs arising spontaneously or due to chronic CMD-exposure demonstrated significant alterations in canonical pathways related to MAPK signaling (IL-8, ErbB, Integrin, and PAK pathway) and oxidative stress (PI3K/AKT and Melatonin pathway) in ABCs from CMD-exposed mice. Oxidative stress can stimulate PI3K/AKT and MAPK signaling pathways. Nox4 was significantly upregulated only in CMD-exposed ABCs and NOX4 activation of PI3K/AKT can lead to increased ROS levels in human cancer cells. The gene encoding Ereg was markedly up-regulated in CMD-exposed mice. Oncogenic KRAS mutations have been shown to induce EREG overexpression. Collectively, all these data suggest that oxidative stress plays a significant role in CMD-induced pulmonary carcinogenesis in rodents and these findings may also be relevant in the context of human lung cancers.


Subject(s)
Bronchial Neoplasms/chemically induced , Cobalt/toxicity , Lung Neoplasms/chemically induced , Oxidative Stress/drug effects , A549 Cells , Adenocarcinoma, Bronchiolo-Alveolar/chemically induced , Adenocarcinoma, Bronchiolo-Alveolar/pathology , Animals , Bronchial Neoplasms/pathology , Carcinogenesis/chemically induced , Cell Line , Dose-Response Relationship, Drug , Dust , Female , Humans , Lung Neoplasms/pathology , Male , Mice , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Pulmonary Alveoli/pathology , Rats , Rats, Inbred F344
8.
PLoS Genet ; 17(3): e1009392, 2021 03.
Article in English | MEDLINE | ID: mdl-33661925

ABSTRACT

The natural history of tuberculosis (TB) is characterized by a large inter-individual outcome variability after exposure to Mycobacterium tuberculosis. Specifically, some highly exposed individuals remain resistant to M. tuberculosis infection, as inferred by tuberculin skin test (TST) or interferon-gamma release assays (IGRAs). We performed a genome-wide association study of resistance to M. tuberculosis infection in an endemic region of Southern Vietnam. We enrolled household contacts (HHC) of pulmonary TB cases and compared subjects who were negative for both TST and IGRA (n = 185) with infected individuals (n = 353) who were either positive for both TST and IGRA or had a diagnosis of TB. We found a genome-wide significant locus on chromosome 10q26.2 with a cluster of variants associated with strong protection against M. tuberculosis infection (OR = 0.42, 95%CI 0.35-0.49, P = 3.71×10-8, for the genotyped variant rs17155120). The locus was replicated in a French multi-ethnic HHC cohort and a familial admixed cohort from a hyper-endemic area of South Africa, with an overall OR for rs17155120 estimated at 0.50 (95%CI 0.45-0.55, P = 1.26×10-9). The variants are located in intronic regions and upstream of C10orf90, a tumor suppressor gene which encodes an ubiquitin ligase activating the transcription factor p53. In silico analysis showed that the protective alleles were associated with a decreased expression in monocytes of the nearby gene ADAM12 which could lead to an enhanced response of Th17 lymphocytes. Our results reveal a novel locus controlling resistance to M. tuberculosis infection across different populations.


Subject(s)
Chromosomes, Human, Pair 10 , Disease Resistance/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Mycobacterium tuberculosis , Quantitative Trait Loci , Tuberculosis/genetics , Tuberculosis/microbiology , Alleles , Computational Biology/methods , France , Genotype , Humans , Meta-Analysis as Topic , Population Groups/genetics , South Africa , Vietnam
9.
PLoS Pathog ; 16(8): e1008818, 2020 08.
Article in English | MEDLINE | ID: mdl-32776973

ABSTRACT

Leprosy is a chronic disease caused by Mycobacterium leprae. Worldwide, more than 200,000 new patients are affected by leprosy annually, making it the second most common mycobacterial disease after tuberculosis. The MHC/HLA region has been consistently identified as carrying major leprosy susceptibility variants in different populations at times with inconsistent results. To establish the unambiguous molecular identity of classical HLA class I and class II leprosy susceptibility factors, we applied next-generation sequencing to genotype with high-resolution 11 HLA class I and class II genes in 1,155 individuals from a Vietnamese leprosy case-control sample. HLA alleles belonging to an extended haplotype from HLA-A to HLA-DPB1 were associated with risk to leprosy. This susceptibility signal could be reduced to the HLA-DRB1*10:01~ HLA-DQA1*01:05 alleles which were in complete linkage disequilibrium (LD). In addition, haplotypes containing HLA-DRB3~ HLA-DRB1*12:02 and HLA-C*07:06~ HLA-B*44:03~ HLA-DRB1*07:01 alleles were found as two independent protective factors for leprosy. Moreover, we replicated the previously associated HLA-DRB1*15:01 as leprosy risk factor and HLA-DRB1*04:05~HLA-DQA1*03:03 as protective alleles. When we narrowed the analysis to the single amino acid level, we found that the associations of the HLA alleles were largely captured by four independent amino acids at HLA-DRß1 positions 57 (D) and 13 (F), HLA-B position 63 (E) and HLA-A position 19 (K). Hence, analyses at the amino acid level circumvented the ambiguity caused by strong LD of leprosy susceptibility HLA alleles and identified four distinct leprosy susceptibility factors.


Subject(s)
Amino Acids/genetics , Genetic Predisposition to Disease , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class I/genetics , Leprosy/pathology , Mutation , Adolescent , Adult , Female , Haplotypes , Humans , Leprosy/genetics , Male , Young Adult
10.
PLoS Pathog ; 16(5): e1008565, 2020 05.
Article in English | MEDLINE | ID: mdl-32421744

ABSTRACT

Leprosy is a chronic infectious disease of the skin and peripheral nerves with a strong genetic predisposition. Recent genome-wide approaches have identified numerous common variants associated with leprosy, almost all in the Chinese population. We conducted the first family-based genome-wide association study of leprosy in 622 affected offspring from Vietnam, followed by replication in an independent sample of 1181 leprosy cases and 668 controls of the same ethnic origin. The most significant results were observed within the HLA region, in which six SNPs displayed genome-wide significant associations, all of which were replicated in the independent case/control sample. We investigated the signal in the HLA region in more detail, by conducting a multivariate analysis on the case/control sample of 319 GWAS-suggestive HLA hits for which evidence for replication was obtained. We identified three independently associated SNPs, two located in the HLA class I region (rs1265048: OR = 0.69 [0.58-0.80], combined p-value = 5.53x10-11; and rs114598080: OR = 1.47 [1.46-1.48], combined p-value = 8.77x10-13), and one located in the HLA class II region (rs3187964 (OR = 1.67 [1.55-1.80], combined p-value = 8.35x10-16). We also validated two previously identified risk factors for leprosy: the missense variant rs3764147 in the LACC1 gene (OR = 1.52 [1.41-1.63], combined p-value = 5.06x10-14), and the intergenic variant rs6871626 located close to the IL12B gene (OR = 0.73 [0.61-0.84], combined p-value = 6.44x10-8). These results shed new light on the genetic control of leprosy, by dissecting the influence of HLA SNPs, and validating the independent role of two additional variants in a large Vietnamese sample.


Subject(s)
Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class I/genetics , Leprosy/genetics , Polymorphism, Single Nucleotide , Female , Genome-Wide Association Study , Humans , Interleukin-12 Subunit p40/genetics , Intracellular Signaling Peptides and Proteins/genetics , Leprosy/epidemiology , Male
11.
Arch Toxicol ; 94(7): 2523-2541, 2020 07.
Article in English | MEDLINE | ID: mdl-32306082

ABSTRACT

Ginkgo biloba extract (GBE) is used in traditional Chinese medicine as a herbal supplement for improving memory. Exposure of B6C3F1/N mice to GBE in a 2-year National Toxicology Program (NTP) bioassay resulted in a dose-dependent increase in hepatocellular carcinomas (HCC). To identify key microRNAs that modulate GBE-induced hepatocarcinogenesis, we compared the global miRNA expression profiles in GBE-exposed HCC (GBE-HCC) and spontaneous HCC (SPNT-HCC) with age-matched vehicle control normal livers (CNTL) from B6C3F1/N mice. The number of differentially altered miRNAs in GBE-HCC and SPNT-HCC was 74 (52 up and 22 down) and 33 (15 up and 18 down), respectively. Among the uniquely differentially altered miRNAs in GBE-HCC, miR-31 and one of its predicted targets, Cdk1 were selected for functional validation. A potential miRNA response element (MRE) in the 3'-untranslated regions (3'-UTR) of Cdk1 mRNA was revealed by in silico analysis and confirmed by luciferase assays. In mouse hepatoma cell line HEPA-1 cells, we demonstrated an inverse correlation between miR-31 and CDK1 protein levels, but no change in Cdk1 mRNA levels, suggesting a post-transcriptional effect. Additionally, a set of miRNAs (miRs-411, 300, 127, 134, 409-3p, and 433-3p) that were altered in the GBE-HCCs were also altered in non-tumor liver samples from the 90-day GBE-exposed group compared to the vehicle control group, suggesting that some of these miRNAs could serve as potential biomarkers for GBE exposure or hepatocellular carcinogenesis. These data increase our understanding of miRNA-mediated epigenetic regulation of GBE-mediated hepatocellular carcinogenesis in B6C3F1/N mice.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/genetics , Cell Transformation, Neoplastic/genetics , Liver Neoplasms/genetics , MicroRNAs/genetics , Plant Extracts/toxicity , Transcriptome , 3' Untranslated Regions , Animals , Biomarkers, Tumor/metabolism , CDC2 Protein Kinase/genetics , CDC2 Protein Kinase/metabolism , Carcinoma, Hepatocellular/chemically induced , Carcinoma, Hepatocellular/metabolism , Cell Line, Tumor , Cell Transformation, Neoplastic/chemically induced , Cell Transformation, Neoplastic/metabolism , Epigenesis, Genetic , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Ginkgo biloba , Liver Neoplasms/chemically induced , Liver Neoplasms/metabolism , Male , Mice , MicroRNAs/metabolism , Time Factors
12.
Toxicol Pathol ; 48(2): 338-349, 2020 02.
Article in English | MEDLINE | ID: mdl-31826744

ABSTRACT

Human exposure to pentabromodiphenyl ether (PBDE) mixture (DE-71) and its PBDE-47 congener can occur both in utero and during lactation. Here, we tested the hypothesis that PBDE-induced neonatal hepatic transcriptomic alterations in Wistar Han rat pups can inform on potential toxicity and carcinogenicity after longer term PBDE exposures. Wistar Han rat dams were exposed to either DE-71 or PBDE-47 daily from gestation day (GD 6) through postnatal day 4 (PND 4). Total plasma thyroxine (T4) was decreased in PND 4 pups. In liver, transcripts for CYPs and conjugation enzymes, Nrf2, and ABC transporters were upregulated. In general, the hepatic transcriptomic alterations after exposure to DE-71 or PBDE-47 were similar and provided early indicators of oxidative stress and metabolic alterations, key characteristics of toxicity processes. The transcriptional benchmark dose lower confidence limits of the most sensitive biological processes were lower for PBDE-47 than for the PBDE mixture. Neonatal rat liver transcriptomic data provide early indicators on molecular pathway alterations that may lead to toxicity and/or carcinogenicity if the exposures continue for longer durations. These early toxicogenomic indicators may be used to help prioritize chemicals for a more complete toxicity and cancer risk evaluation.


Subject(s)
Halogenated Diphenyl Ethers/toxicity , Liver/drug effects , Maternal Exposure/adverse effects , Prenatal Exposure Delayed Effects/pathology , Transcriptome/drug effects , Animals , Animals, Newborn , Female , Halogenated Diphenyl Ethers/blood , Male , Pregnancy , Prenatal Exposure Delayed Effects/blood , Rats , Rats, Wistar
13.
Proc Natl Acad Sci U S A ; 116(31): 15616-15624, 2019 07 30.
Article in English | MEDLINE | ID: mdl-31308240

ABSTRACT

Type-1 reactions (T1R) are pathological inflammatory episodes and main contributors to nerve damage in leprosy. Here, we evaluate the genewise enrichment of rare protein-altering variants in 7 genes where common variants were previously associated with T1R. We selected 474 Vietnamese leprosy patients of which 237 were T1R-affected and 237 were T1R-free matched controls. Genewise enrichment of nonsynonymous variants was tested with both kernel-based (sequence kernel association test [SKAT]) and burden methods. Of the 7 genes tested 2 showed statistical evidence of association with T1R. For the LRRK2 gene an enrichment of nonsynonymous variants was observed in T1R-free controls (PSKAT-O = 1.6 × 10-4). This genewise association was driven almost entirely by the gain-of-function variant R1628P (P = 0.004; odds ratio = 0.29). The second genewise association was found for the Parkin coding gene PRKN (formerly PARK2) where 7 rare variants were enriched in T1R-affected cases (PSKAT-O = 7.4 × 10-5). Mutations in both PRKN and LRRK2 are known causes of Parkinson's disease (PD). Hence, we evaluated to what extent such rare amino acid changes observed in T1R are shared with PD. We observed that amino acids in Parkin targeted by nonsynonymous T1R-risk mutations were also enriched for mutations implicated in PD (P = 1.5 × 10-4). Hence, neuroinflammation in PD and peripheral nerve damage due to inflammation in T1R share overlapping genetic control of pathogenicity.


Subject(s)
Leprosy , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 , Mutation , Parkinson Disease , Ubiquitin-Protein Ligases , Female , Humans , Leprosy/genetics , Leprosy/metabolism , Leprosy/pathology , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Male , Parkinson Disease/genetics , Parkinson Disease/metabolism , Parkinson Disease/pathology , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism
14.
Arch Toxicol ; 93(8): 2219-2235, 2019 08.
Article in English | MEDLINE | ID: mdl-31278416

ABSTRACT

Epigenetic modifications, such as DNA methylation, play an important role in carcinogenesis. In a recent NTP study, chronic exposure of B6C3F1/N mice to Ginkgo biloba extract (GBE) resulted in a high incidence of hepatocellular carcinomas (HCC). Genome-wide promoter methylation profiling on GBE-exposed HCC (2000 mg/kg group), spontaneous HCC (vehicle-control group), and age-matched vehicle control liver was performed to identify differentially methylated genes in GBE-exposed HCC and spontaneous HCC. DNA methylation alterations were correlated to the corresponding global gene expression changes. Compared to control liver, 1296 gene promoters (719 hypermethylated, 577 hypomethylated) in GBE-exposed HCC and 738 (427 hypermethylated, 311 hypomethylated) gene promoters in spontaneous HCC were significantly differentially methylated, suggesting an impact of methylation on GBE-exposed HCC. Differential methylation of promoter regions in relevant cancer genes (cMyc, Spry2, Dusp5) and their corresponding differential gene expression was validated by quantitative pyrosequencing and qRT-PCR, respectively. In conclusion, we have identified differentially methylated promoter regions of relevant cancer genes altered in GBE-exposed HCC compared to spontaneous HCC. Further study of unique sets of differentially methylated genes in chemical-exposed mouse HCC could potentially be used to differentiate treatment-related tumors from spontaneous-tumors in cancer bioassays and provide additional understanding of the underlying epigenetic mechanisms of chemical carcinogenesis.


Subject(s)
Carcinoma, Hepatocellular/chemically induced , DNA Methylation/drug effects , Liver Neoplasms/chemically induced , Plant Extracts/adverse effects , Animals , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Epigenesis, Genetic/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Genome-Wide Association Study , Ginkgo biloba , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Male , Mice, Inbred Strains , Plant Extracts/administration & dosage , Promoter Regions, Genetic , Reproducibility of Results , Toxicity Tests, Chronic
15.
Data Brief ; 21: 2125-2128, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30533462

ABSTRACT

This article describes data related to the research article entitled "Carcinogenic activity of pentabrominated diphenyl ether mixture (DE-71) in rats and mice" (Dunnick et al., 2018). PBDE-induced hepatocellular tumors harbored Hras and Ctnnb1 mutations and the methods for these studies are provided. Tissue levels of PBDE congeners in rats and mice after oral exposure to PBDE mixture increased with increasing dose of PBDE. There was no correlation between AhR status and the incidence of hepatocellular tumors in female Wistar Han rats. This manuscript provides additional information on the methods for conducting mutational analysis, PBDE tissue level determinations, and AhR genotyping.

16.
Toxicol Pathol ; 46(6): 706-718, 2018 08.
Article in English | MEDLINE | ID: mdl-30045675

ABSTRACT

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide; however, the mutational properties of HCC-associated carcinogens remain largely uncharacterized. We hypothesized that mechanisms underlying chemical-induced HCC can be characterized by evaluating the mutational spectra of these tumors. To test this hypothesis, we performed exome sequencing of B6C3F1/N HCCs that arose either spontaneously in vehicle controls ( n = 3) or due to chronic exposure to gingko biloba extract (GBE; n = 4) or methyleugenol (MEG; n = 3). Most archived tumor samples are available as formalin-fixed paraffin-embedded (FFPE) blocks, rather than fresh-frozen (FF) samples; hence, exome sequencing from paired FF and FFPE samples was compared. FF and FFPE samples showed 63% to 70% mutation concordance. Multiple known (e.g., Ctnnb1T41A, BrafV637E) and novel (e.g., Erbb4C559S, Card10A700V, and Klf11P358L) mutations in cancer-related genes were identified. The overall mutational burden was greater for MEG than for GBE or spontaneous HCC samples. To characterize the mutagenic mechanisms, we analyzed the mutational spectra in the HCCs according to their trinucleotide motifs. The MEG tumors clustered closest to Catalogue of Somatic Mutations in Cancer signatures 4 and 24, which are, respectively, associated with benzo(a)pyrene- and aflatoxin-induced HCCs in humans. These results establish a novel approach for classifying liver carcinogens and understanding the mechanisms of hepatocellular carcinogenesis.


Subject(s)
Carcinogens/toxicity , Exome/genetics , Gene Expression Profiling , Liver Neoplasms, Experimental/genetics , Liver/drug effects , Mutation , Sequence Analysis, DNA/methods , Animals , Cryopreservation , DNA, Neoplasm/genetics , Eugenol/analogs & derivatives , Eugenol/toxicity , Female , Formaldehyde/chemistry , Ginkgo biloba , Liver/pathology , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/pathology , Male , Mice, Inbred Strains , Paraffin Embedding , Plant Extracts/toxicity , Reproducibility of Results , Tissue Fixation
17.
PLoS Genet ; 13(8): e1006952, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28793313

ABSTRACT

Leprosy is a human infectious disease caused by Mycobacterium leprae. A strong host genetic contribution to leprosy susceptibility is well established. However, the modulation of the transcriptional response to infection and the mechanism(s) of disease control are poorly understood. To address this gap in knowledge of leprosy pathogenicity, we conducted a genome-wide search for expression quantitative trait loci (eQTL) that are associated with transcript variation before and after stimulation with M. leprae sonicate in whole blood cells. We show that M. leprae antigen stimulation mainly triggered the upregulation of immune related genes and that a substantial proportion of the differential gene expression is genetically controlled. Indeed, using stringent criteria, we identified 318 genes displaying cis-eQTL at an FDR of 0.01, including 66 genes displaying response-eQTL (reQTL), i.e. cis-eQTL that showed significant evidence for interaction with the M. leprae stimulus. Such reQTL correspond to regulatory variations that affect the interaction between human whole blood cells and M. leprae sonicate and, thus, likely between the human host and M. leprae bacilli. We found that reQTL were significantly enriched among binding sites of transcription factors that are activated in response to infection, and that they were enriched among single nucleotide polymorphisms (SNPs) associated with susceptibility to leprosy per se and Type-I Reaction, and seven of them have been targeted by recent positive selection. Our study suggested that natural selection shaped our genomic diversity to face pathogen exposure including M. leprae infection.


Subject(s)
Antigens, Bacterial/immunology , Leprosy/genetics , Quantitative Trait Loci , Down-Regulation , Genetic Association Studies , Genetic Predisposition to Disease , Host-Pathogen Interactions/genetics , Humans , Leprosy/immunology , Mycobacterium leprae , Polymorphism, Single Nucleotide , Principal Component Analysis , RNA, Bacterial/isolation & purification , Up-Regulation
18.
PLoS Genet ; 13(2): e1006637, 2017 02.
Article in English | MEDLINE | ID: mdl-28222097

ABSTRACT

Leprosy Type-1 Reactions (T1Rs) are pathological inflammatory responses that afflict a sub-group of leprosy patients and result in peripheral nerve damage. Here, we employed a family-based GWAS in 221 families with 229 T1R-affect offspring with stepwise replication to identify risk factors for T1R. We discovered, replicated and validated T1R-specific associations with SNPs located in chromosome region 10p21.2. Combined analysis across the three independent samples resulted in strong evidence of association of rs1875147 with T1R (p = 4.5x10-8; OR = 1.54, 95% CI = 1.32-1.80). The T1R-risk locus was restricted to a lncRNA-encoding genomic interval with rs1875147 being an eQTL for the lncRNA. Since a genetic overlap between leprosy and inflammatory bowel disease (IBD) has been detected, we evaluated if the shared genetic control could be traced to the T1R endophenotype. Employing the results of a recent IBD GWAS meta-analysis we found that 10.6% of IBD SNPs available in our dataset shared a common risk-allele with T1R (p = 2.4x10-4). This finding points to a substantial overlap in the genetic control of clinically diverse inflammatory disorders.


Subject(s)
Genetic Predisposition to Disease , Inflammatory Bowel Diseases/genetics , Leprosy/genetics , RNA, Long Noncoding/genetics , Female , Gene Expression Regulation , Genome-Wide Association Study , Humans , Inflammatory Bowel Diseases/complications , Inflammatory Bowel Diseases/pathology , Leprosy/complications , Leprosy/pathology , Male , Nerve Degeneration/complications , Nerve Degeneration/genetics , Nerve Degeneration/pathology , Polymorphism, Single Nucleotide , Quantitative Trait Loci/genetics , RNA, Long Noncoding/biosynthesis , Risk Factors , Vietnam
19.
J Biol Chem ; 292(12): 4925-4941, 2017 03 24.
Article in English | MEDLINE | ID: mdl-28100785

ABSTRACT

Protein phosphatase 2A (PP2A) plays important roles in controlling mitosis in all eukaryotic cells. The form of PP2A that controls mitosis is associated with a conserved regulatory subunit that is called B55 in vertebrates and Cdc55 in budding yeast. The activity of this form of PP2A can be inhibited by binding of conserved Igo/ENSA proteins. Although the mechanisms that activate Igo/ENSA to bind and inhibit PP2A are well understood, little is known about how Igo/Ensa are inactivated. Here, we have analyzed regulation of Igo/ENSA in the context of a checkpoint pathway that links mitotic entry to membrane growth in budding yeast. Protein kinase C (Pkc1) relays signals in the pathway by activating PP2ACdc55 We discovered that constitutively active Pkc1 can drive cells through a mitotic checkpoint arrest, which suggests that Pkc1-dependent activation of PP2ACdc55 plays a critical role in checkpoint signaling. We therefore used mass spectrometry to determine how Pkc1 modifies the PP2ACdc55 complex. This revealed that Pkc1 induces changes in the phosphorylation of multiple subunits of the complex, as well as dissociation of Igo/ENSA. Pkc1 directly phosphorylates Cdc55 and Igo/ENSA, and phosphorylation site mapping and mutagenesis indicate that phosphorylation of Cdc55 contributes to Igo/ENSA dissociation. Association of Igo2 with PP2ACdc55 is regulated during the cell cycle, yet mutation of Pkc1-dependent phosphorylation sites on Cdc55 and Igo2 did not cause defects in mitotic progression. Together, the data suggest that Pkc1 controls PP2ACdc55 by multiple overlapping mechanisms.


Subject(s)
Cell Cycle Proteins/metabolism , Protein Kinase C/metabolism , Protein Phosphatase 2/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/metabolism , Amino Acid Sequence , Cell Cycle Proteins/analysis , Models, Molecular , Phosphorylation , Protein Binding , Protein Kinase C/analysis , Protein Phosphatase 2/analysis , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae Proteins/analysis , Sequence Alignment
20.
s.l; s.n; 2017. 16 p. ilus, tab, graf.
Non-conventional in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLPROD, Sec. Est. Saúde SP, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1087674

ABSTRACT

Leprosy Type-1 Reactions (T1Rs) are pathological inflammatory responses that afflict a sub-group of leprosy patients and result in peripheral nerve damage. Here, we employed a family-based GWAS in 221 families with 229 T1R-affect offspring with stepwise replication to identify risk factors for T1R. We discovered, replicated and validated T1R-specific associations with SNPs located in chromosome region 10p21.2. Combined analysis across the three independent samples resulted in strong evidence of association of rs1875147 with T1R (p = 4.5x10-8; OR = 1.54, 95% CI = 1.32-1.80). The T1R-risk locus was restricted to a lncRNA-encoding genomic interval with rs1875147 being an eQTL for the lncRNA. Since a genetic overlap between leprosy and inflammatory bowel disease (IBD) has been detected, we evaluated if the shared genetic control could be traced to the T1R endophenotype. Employing the results of a recent IBD GWAS meta-analysis we found that 10.6% of IBD SNPs available in our dataset shared a common risk-allele with T1R (p = 2.4x10-4). This finding points to a substantial overlap in the genetic control of clinically diverse inflammatory disorders.


Subject(s)
Humans , Male , Female , Genome-Wide Association Study , Leprosy/genetics , Leprosy/pathology , Genetic Predisposition to Disease , RNA, Long Noncoding/genetics
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