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1.
Mamm Genome ; 31(7-8): 215-227, 2020 08.
Article in English | MEDLINE | ID: mdl-32661568

ABSTRACT

Selective breeding of the domestic dog (Canis lupus familiaris) rigidly retains desirable features, and could inadvertently fix disease-causing variants within a breed. We combine phenotypic data from > 72,000 dogs with a large genotypic dataset to search for genes associated with cancer mortality and longevity in pedigree dog breeds. We validated previous findings that breeds with higher average body weight have higher cancer mortality rates and lower life expectancy. We identified a significant positive correlation between life span and cancer mortality residuals corrected for body weight, implying that long-lived breeds die more frequently from cancer compared to short-lived breeds. We replicated a number of known genetic associations with body weight (IGF1, GHR, CD36, SMAD2 and IGF2BP2). Subsequently, we identified five genetic variants in known cancer-related genes (located within SIPA1, ADCY7 and ARNT2) that could be associated with cancer mortality residuals corrected for confounding factors. One putative genetic variant was marginally significantly associated with longevity residuals that had been corrected for the effects of body weight; this genetic variant is located within PRDX1, a peroxiredoxin that belongs to an emerging class of pro-longevity associated genes. This research should be considered as an exploratory analysis to uncover associations between genes and longevity/cancer mortality.


Subject(s)
Dog Diseases/genetics , Dog Diseases/mortality , Genetic Predisposition to Disease , Longevity/genetics , Neoplasms/veterinary , Alleles , Animals , Biomarkers , Body Weight , Breeding , Dogs , Genetic Association Studies , Genetic Variation , Genotype , Pedigree , Phenotype , Polymorphism, Single Nucleotide
2.
J Virol ; 93(20)2019 10 15.
Article in English | MEDLINE | ID: mdl-31375574

ABSTRACT

Human immunodeficiency virus type 1 (HIV-1) has evolved elaborate ways to evade immune cell recognition, including downregulation of classical HLA class I (HLA-I) from the surfaces of infected cells. Recent evidence identified HLA-E, a nonclassical HLA-I, as an important part of the antiviral immune response to HIV-1. Changes in HLA-E surface levels and peptide presentation can prompt both CD8+ T-cell and natural killer (NK) cell responses to viral infections. Previous studies reported unchanged or increased HLA-E levels on HIV-1-infected cells. Here, we examined HLA-E surface levels following infection of CD4+ T cells with primary HIV-1 strains and observed that a subset downregulated HLA-E. Two primary strains of HIV-1 that induced the strongest reduction in surface HLA-E expression were chosen for further testing. Expression of single Nef or Vpu proteins in a T-cell line, as well as tail swap experiments exchanging the cytoplasmic tail of HLA-A2 with that of HLA-E, demonstrated that Nef modulated HLA-E surface levels and targeted the cytoplasmic tail of HLA-E. Furthermore, infection of primary CD4+ T cells with HIV-1 mutants showed that a lack of functional Nef (and Vpu to some extent) impaired HLA-E downmodulation. Taken together, the results of this study demonstrate for the first time that HIV-1 can downregulate HLA-E surface levels on infected primary CD4+ T cells, potentially rendering them less vulnerable to CD8+ T-cell recognition but at increased risk of NKG2A+ NK cell killing.IMPORTANCE For almost two decades, it was thought that HIV-1 selectively downregulated the highly expressed HLA-I molecules HLA-A and HLA-B from the cell surface in order to evade cytotoxic-T-cell recognition, while leaving HLA-C and HLA-E molecules unaltered. It was stipulated that HIV-1 infection thereby maintained inhibition of NK cells via inhibitory receptors that bind HLA-C and HLA-E. This concept was recently revised when a study showed that primary HIV-1 strains reduce HLA-C surface levels, whereas the cell line-adapted HIV-1 strain NL4-3 lacks this ability. Here, we demonstrate that infection with distinct primary HIV-1 strains results in significant downregulation of surface HLA-E levels. Given the increasing evidence for HLA-E as an important modulator of CD8+ T-cell and NKG2A+ NK cell functions, this finding has substantial implications for future immunomodulatory approaches aimed at harnessing cytotoxic cellular immunity against HIV.


Subject(s)
Gene Expression Regulation , HIV Infections/genetics , HIV Infections/virology , HIV-1/physiology , Histocompatibility Antigens Class I/genetics , Host-Pathogen Interactions/genetics , nef Gene Products, Human Immunodeficiency Virus/metabolism , Biomarkers , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cell Line , Cell Membrane/metabolism , HIV Infections/immunology , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class I/metabolism , Host-Pathogen Interactions/immunology , Humans , Immunophenotyping , nef Gene Products, Human Immunodeficiency Virus/genetics , HLA-E Antigens
3.
Dev Biol ; 416(2): 361-72, 2016 08 15.
Article in English | MEDLINE | ID: mdl-27343897

ABSTRACT

Regulation of gene expression at the level of transcriptional elongation has been shown to be important in stem cells and tumour cells, but its role in the whole animal is only now being fully explored. Neural crest cells (NCCs) are a multipotent population of cells that migrate during early development from the dorsal neural tube throughout the embryo where they differentiate into a variety of cell types including pigment cells, cranio-facial skeleton and sensory neurons. Specification of NCCs is both spatially and temporally regulated during embryonic development. Here we show that components of the transcriptional elongation regulatory machinery, CDK9 and CYCLINT1 of the P-TEFb complex, are required to regulate neural crest specification. In particular, we show that expression of the proto-oncogene c-Myc and c-Myc responsive genes are affected. Our data suggest that P-TEFb is crucial to drive expression of c-Myc, which acts as a 'gate-keeper' for the correct temporal and spatial development of the neural crest.


Subject(s)
Cyclin T/genetics , Cyclin-Dependent Kinase 9/genetics , Gene Expression Regulation, Developmental , Genes, myc , Neural Crest/embryology , Positive Transcriptional Elongation Factor B/genetics , Transcription Elongation, Genetic , Xenopus Proteins/genetics , Xenopus laevis/embryology , Animals , Cyclin T/deficiency , Cyclin-Dependent Kinase 9/deficiency , Isoxazoles/pharmacology , Leflunomide , Morpholinos/pharmacology , Positive Transcriptional Elongation Factor B/deficiency , Proto-Oncogene Proteins c-myc/biosynthesis , RNA Polymerase II/metabolism , SOXE Transcription Factors/biosynthesis , SOXE Transcription Factors/genetics , Transcription Elongation, Genetic/drug effects , Transcription, Genetic , Xenopus Proteins/deficiency , Xenopus laevis/genetics
4.
Haematologica ; 102(6): 1105-1111, 2017 06.
Article in English | MEDLINE | ID: mdl-28183851

ABSTRACT

Recent studies suggest that circulating tumor cells and cell-free DNA may represent powerful non-invasive tools for monitoring disease in patients with solid and hematologic malignancies. Here, we conducted a pilot study in 27 myeloma patients to explore the clonotypic V(D)J rearrangement for monitoring circulating myeloma cells and cell-free myeloma DNA. Next-generation sequencing was used to define the myeloma V(D)J rearrangement and for subsequent peripheral blood tracking after treatment initiation. Positivity for circulating myeloma cells/cell-free myeloma was associated with conventional remission status (P<0.001) and 91% of non-responders/progressors versus 41% of responders had evidence of persistent circulating myeloma cells/cell-free myeloma DNA (P<0.001). About half of the partial responders showed complete clearance of circulating myeloma cells/cell-free myeloma DNA despite persistent M-protein, suggesting that these markers are less inert than the M-protein, rely more on cell turnover and, therefore, decline more rapidly after initiation of effective treatment. Positivity for circulating myeloma cells and for cell-free myeloma DNA were associated with each other (P=0.042), but discordant in 30% of cases. This indicates that cell-free myeloma DNA may not be generated entirely by circulating myeloma cells and may reflect overall tumor burden. Prospective studies need to define the predictive potential of high-sensitivity determination of circulating myeloma cells and DNA in the monitoring of multiple myeloma.


Subject(s)
DNA, Neoplasm/analysis , Multiple Myeloma/diagnosis , Neoplastic Cells, Circulating/metabolism , V(D)J Recombination/genetics , Aged , Biomarkers , Female , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Pilot Projects , Tumor Burden
5.
Br J Nutr ; 115(10): 1699-710, 2016 May 28.
Article in English | MEDLINE | ID: mdl-26984113

ABSTRACT

Diets rich in fruits and vegetables (FV), which contain (poly)phenols, protect against age-related inflammation and chronic diseases. T-lymphocytes contribute to systemic cytokine production and are modulated by FV intake. Little is known about the relative potency of different (poly)phenols in modulating cytokine release by lymphocytes. We compared thirty-one (poly)phenols and six (poly)phenol mixtures for effects on pro-inflammatory cytokine release by Jurkat T-lymphocytes. Test compounds were incubated with Jurkat cells for 48 h at 1 and 30 µm, with or without phorbol ester treatment at 24 h to induce cytokine release. Three test compounds that reduced cytokine release were further incubated with primary lymphocytes at 0·2 and 1 µm for 24 h, with lipopolysaccharide added at 5 h. Cytokine release was measured, and generation of H2O2 by test compounds was determined to assess any potential correlations with cytokine release. A number of (poly)phenols significantly altered cytokine release from Jurkat cells (P<0·05), but H2O2 generation did not correlate with cytokine release. Resveratrol, isorhamnetin, curcumin, vanillic acid and specific (poly)phenol mixtures reduced pro-inflammatory cytokine release from T-lymphocytes, and there was evidence for interaction between (poly)phenols to further modulate cytokine release. The release of interferon-γ induced protein 10 by primary lymphocytes was significantly reduced following treatment with 1 µm isorhamnetin (P<0·05). These results suggest that (poly)phenols derived from onions, turmeric, red grapes, green tea and açai berries may help reduce the release of pro-inflammatory mediators in people at risk of chronic inflammation.


Subject(s)
Cytokines/metabolism , Lymphocytes/drug effects , Polyphenols/pharmacology , Cell Survival/drug effects , Chronic Disease , Curcuma/chemistry , Curcumin/pharmacology , Euterpe/chemistry , Female , Humans , Hydrogen Peroxide/metabolism , Inflammation/drug therapy , Jurkat Cells , Lipopolysaccharides/metabolism , Lymphocytes/metabolism , Middle Aged , Onions/chemistry , Quercetin/analogs & derivatives , Quercetin/pharmacology , Resveratrol , Stilbenes/pharmacology , Tea/chemistry , Vanillic Acid/pharmacology , Vitis/chemistry
6.
Nutr J ; 14: 50, 2015 May 14.
Article in English | MEDLINE | ID: mdl-25972154

ABSTRACT

BACKGROUND: Members of the family Zingiberaceae including turmeric, ginger, Javanese ginger, and galangal have been used for centuries in traditional medicine. Preclinical studies of Zingiberaceae extracts have shown analgesic properties. This study aims to systematically review and meta-analyze whether extracts from Zingiberaceae are clinically effective hypoalgesic agents. METHODS: Literature was screened from electronic databases using the key words Zingiberaceae AND pain OR visual analogue score (VAS) to identify randomized trials. From this search, 18 studies were identified, and of these, 8 randomized, double-blinded, placebo-controlled trials were found that measured pain by VAS for inclusion in the meta-analysis. RESULTS: Findings indicated significant efficacy of Zingiberaceae extracts in reducing subjective chronic pain (SMD - 0.67; 95 % CI - 1.13 to - 0.21; P = 0.004). A linear dose-effect relationship was apparent between studies (R(2) = 0.71). All studies included in the systematic review reported a good safety profile for extracts, without the renal risks associated with non-steroidal anti-inflammatory drugs, and with similar effectiveness. CONCLUSION: Our findings indicated that Zingiberaceae extracts are clinically effective hypoalgesic agents and the available data show a better safety profile than non-steroidal anti-inflammatory drugs. However, both non-steroidal anti-inflammatory drugs and Zingiberaceae have been associated with a heightened bleeding risk, and there have been no comparator trials of this risk. Further clinical studies are recommended to identify the most effective type of Zingiberaceae extract and rigorously compare safety, including bleeding risk.


Subject(s)
Analgesics/therapeutic use , Chronic Pain/diet therapy , Plant Extracts/therapeutic use , Zingiberaceae , Analgesics/administration & dosage , Analgesics/adverse effects , Chronic Pain/physiopathology , Humans , Plant Extracts/administration & dosage , Treatment Outcome
7.
Age (Dordr) ; 31(4): 365-72, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19697157

ABSTRACT

Aging in human skin is the composite of time-dependent intrinsic aging plus photoaging induced by chronic exposure to ultraviolet radiation. Nuclear hormone receptors coordinate diverse processes including metabolic homeostasis. Liver X receptor ß (LXRß) is a close human homologue of daf-12, a regulator of nematode longevity. LXRß is positively regulated by sirtuin-1 and resveratrol, while LXRß-null mice show transcriptional profiles similar to those seen in aged human skin. In these studies, we examined LXRß expression in aged and photoaged human skin. Volunteers were recruited to assess intrinsic aging and photoaging. Epidermal LXRß mRNA was examined by in situ hybridization while protein was identified by immunofluorescence. No significant changes were observed in either LXRß mRNA or protein expression between young and aged volunteers (mRNA p = 0.90; protein p = 0.26). Similarly, LXRß protein expression was unaltered in photoaged skin (p = 0.75). Our data therefore suggest that, while not playing a major role in skin aging, robust cutaneous expression implies a fundamental role for LXRß in epidermal biology.


Subject(s)
Epidermis/metabolism , Gene Expression Regulation, Developmental , Orphan Nuclear Receptors/genetics , RNA, Messenger/genetics , Skin Aging/genetics , Adolescent , Adult , Aged , Biopsy , Blotting, Western , Epidermal Cells , Female , Humans , In Situ Hybridization , Liver X Receptors , Male , Microscopy, Fluorescence , Middle Aged , Orphan Nuclear Receptors/biosynthesis , Receptors, Cytoplasmic and Nuclear/biosynthesis , Young Adult
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