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1.
Arch Med Res ; 53(2): 163-169, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34384609

RESUMO

BACKGROUND: Interleukin (IL)-17A has a dual role in tumor immunity, promotes anti-tumor responses and facilitates angiogenesis by interacting with IL-17 receptor A (IL-17RA). Although IL-17A has been associated with the pathogenesis of papillary thyroid carcinoma (PTC), the nucleotide variability at the IL17A and IL17RA genes is still poorly characterized. AIM: To assess the contribution of the IL17A (-197 G >A, rs2275913) and IL17RA (-947 A >G, rs4819554) single nucleotide polymorphisms (SNP) on the development and progression of PTC and on IL-17 plasma levels. METHODS: We studied 188 PTC patients and 170 healthy controls. SNPs were identified using PCR-amplified DNA and restriction fragment length polymorphism (RFLP) techniques. Plasma levels of IL-17A was evaluated in 83 PTC patients using ELISA. Statistical analyses were performed to evaluate the associations between SNPs and clinicohistopathological features of PTC and IL-17A levels. RESULTS: No significant difference was observed regarding the allele and genotype distributions of both SNPs between PTC patients and controls. The IL17A GA was associated with poor biochemical and structural incomplete response to therapy, whereas no influence over the IL-17A expression was observed. The IL17RA AG was significantly associated with small-sized tumors, initial tumor stage at diagnosis and better response to therapy. CONCLUSIONS: The IL17A SNP may predict an aggressive manifestation of PTC, whereas the IL17RA SNP was associated with a more favorable clinical outcome.


Assuntos
Interleucina-17 , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Interleucina-17/genética , Interleucina-17/metabolismo , Polimorfismo de Nucleotídeo Único , Prognóstico , Receptores de Interleucina-17/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética
2.
PLoS One ; 12(1): e0169032, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28045999

RESUMO

The immune checkpoint HLA-G prevents maternal rejection of the fetus and contributes in cancer invasion and acceptance of allografts. The 5' and 3' regulatory regions of the HLA-G gene are polymorphic and balancing selection probably maintains this variability. It is proposed that nucleotide variations may affect the level of HLA-G expression. To investigate this issue we aimed to analyze how haplotypes of the 3' untranslated region (3'UTR) with highest worldwide frequencies, namely UTR-1, UTR-2, UTR-3, UTR-4, UTR-5, UTR-18 and UTR-7, impact the expression of a luciferase reporter gene in vitro. Experiments performed with the HLA-G positive cell lines JEG-3 (choricarcinoma) and FON (melanoma), and with the HLA-G negative cell lines M8 (melanoma) and U251MG (glioblastoma) showed that the HLA-G 3'UTR polymorphism influences the response to endogenous cellular factors and may vary according to the cell type. UTR-5 and UTR-7 impact the activity of luciferase the most whereas UTR-2, UTR-3, UTR-4, and UTR-18 have intermediate impact, and UTR-1 has the lowest impact. These results corroborate the previous associations between amounts of plasma sHLA-G levels and 3'UTR haplotypes in healthy individuals and reinforce that 3'UTR typing may be a predictor of the genetic predisposition of an individual to express different levels of HLA-G.


Assuntos
Regiões 3' não Traduzidas/genética , Antígenos HLA-G/genética , Haplótipos/genética , Pareamento de Bases/genética , Sequência de Bases , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Mutação INDEL/genética , Luciferases/metabolismo , Mutagênese Sítio-Dirigida , Polimorfismo Genético
3.
Placenta ; 49: 33-36, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28012452

RESUMO

INTRODUCTION: Expression of HLA-E molecule in the placental extravillous trophoblast is associated with immune system cell inhibition, resulting in immune tolerance to fetus during pregnancy. HIV-1 can infect trophoblast cells and modify the expression of HLA-E, which may inhibit the cytotoxic activity of the immune system. AIM: The aim of this study was to evaluate HLA-E expression in third trimester placental tissue of women infected with HIV-1 and uninfected women. METHODS: We performed an immunohistochemistry assay to evaluate HLA-E staining in the placental tissue of 99 HIV-1 infected and 85 uninfected women. A pathologist analyzed and classified the HLA-E expression in the placental cells. RESULTS: Irrespective of the HIV status, HLA-E staining was observed in the extravillous trophoblast cells, endothelial cells and Hofbauer cells, but not in the syncytiotrophoblast. HLA-E staining showed no significant difference between the placental tissue of women infected with HIV-1 and uninfected women (P = 0.76). Considering HIV-1 infected women, HLA-E staining was not influenced by HIV-1 viral load (P = 0.48), CD4+ T-cell count (P = 0.10) and antiretroviral therapy used during pregnancy (P = 0.54). DISCUSSION: Despite the presence of HIV-1 infection, the expression of HLA-E molecules in the placental tissue was not modified when the infection was under antiretroviral therapy control.


Assuntos
Infecções por HIV/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Placenta/metabolismo , Adolescente , Adulto , Feminino , HIV-1 , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Trofoblastos/metabolismo , Adulto Jovem , Antígenos HLA-E
4.
Clin Exp Rheumatol ; 35(2): 247-254, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27908303

RESUMO

OBJECTIVES: Neutrophils play a major role in rheumatoid arthritis (RA) pathogenesis. We aimed to evaluate if neutrophil DNA damage in RA patients is associated with the disease activity, autoantibodies status, carriage of the RA shared epitope (SE) and treatment. METHODS: DNA damage was assessed by alkaline comet assay in peripheral blood (77 patients and 55 healthy controls) and in 10 RA synovial fluid neutrophils. Evaluation of the respiratory burst of 30 patients with RA and 30 healthy controls was done. RESULTS: Compared to controls, RA patients exhibited increased neutrophil DNA damage. RA synovial fluid cells DNA damage was increased when compared to OA synovial fluids cells. In addition, our study shows that anti-TNF-α therapy reduces the frequency of DNA damage. Patients with simple or double dose of shared epitope presented a higher frequency of DNA damage compared to patients without the allele. Positive correlation was found between neutrophil DNA damage and DAS-28 and ROS production. CONCLUSIONS: Our results suggest that an increase of respiratory burst of neutrophils reflects the higher levels of DNA damage in neutrophils and a positive correlation between DNA damage and disease activity shows the importance of oxidative stress in the pathogenesis of RA.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Dano ao DNA , Epitopos/imunologia , Antígenos HLA/imunologia , Neutrófilos/imunologia , Neutrófilos/patologia , Adulto , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Autoanticorpos/sangue , Estudos de Casos e Controles , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Epitopos/sangue , Epitopos/genética , Feminino , Antígenos HLA/sangue , Antígenos HLA/genética , Humanos , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória , Índice de Gravidade de Doença , Líquido Sinovial/imunologia , Líquido Sinovial/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia
5.
Clin Endocrinol (Oxf) ; 86(4): 597-605, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27914217

RESUMO

BACKGROUND: HLA-G is a nonclassical class I histocompatibility molecule implicated on the immune escape mechanism of tumour cells. We evaluated the genetic diversity of HLA-G 3' untranslated region (3'UTR) and associated polymorphic sites with clinical presentation and with the magnitude of HLA-G thyroid expression. PATIENTS AND METHODS: Polymorphic sites at 3'UTR (14bpINS/DEL, +3003C/T, +3010C/G, +3027A/C, +3035C/T, +3142C/G, +3187A/G, +3196C/G) were characterized by sequencing analyses in blood samples of 72 patients exhibiting papillary thyroid carcinoma (PTC), 22 follicular thyroid carcinomas (FTC), 19 follicular adenomas (FA), 21 colloid goitres and 156 healthy controls. RESULTS: Compared to goitre and/or controls, patients with PTC exhibited higher frequency of 14bpDEL (P = 0·030), +3010G (P = 0·034), +3010CG (P = 0·044), +3142CG (P = 0·040), +3035C (P = 0·050) and +3187GG (P = 0·032). Patients with FTC presented higher frequency of 14bpINS/DEL (P = 0·020). The UTR-5 haplotype was underrepresented in PTC (P = 0·050). The +3003TT was more frequent in patients with PTC older than 45 years (P = 0·030). Male patients had a higher frequency of +3196GG (P = 0·040). Tumour multicentricity was associated with UTR-2 (P = 0·030). The following associations were observed in PTC and FTC combined: i) tumour size <2 cm with 14bpINS/INS (P = 0·030); ii) multicentricity with +3035CC (P = 0·030) and +3196GG (P = 0·030); iii) decreased thyroid HLA-G expression with +3196C and +3196CC; and iv) moderate HLA-G thyroid staining with UTR-2. CONCLUSIONS: HLA-G 3'UTR polymorphisms associated with a greater magnitude of HLA-G production were associated with differentiated thyroid tumours and with variables implicated in poor prognosis. These findings corroborate the unfavourable role of HLA-G in thyroid cancer.


Assuntos
Regiões 3' não Traduzidas/genética , Antígenos HLA-G/biossíntese , Neoplasias da Glândula Tireoide/genética , Adulto , Idoso , Carcinoma/genética , Carcinoma Papilar , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Análise de Sequência de DNA , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/imunologia , Neoplasias da Glândula Tireoide/patologia
6.
J Gen Virol ; 97(10): 2742-2752, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27449667

RESUMO

Most human T-lymphotropic virus type 1 (HTLV-1)-infected patients remain asymptomatic throughout life. The factors associated with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development have not been fully elucidated; immunological and genetic factors may be involved. The association of 14 bp INS/DEL HLA-G polymorphism with HTLV-1 infection susceptibility has been reported previously. Here, other polymorphic sites at the HLA-G 3'-UTR (14-bp D/I, +3003C/T, +3010C/G, +3027A/C, +3035C/T, +3142C/G, +3187A/G and +3196C/G) were evaluated in 37 HTLV-1-infected individuals exhibiting HAM/TSP, 45 HTLV-1 asymptomatic carriers (HAC) and 153 uninfected individuals, followed up at University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil. It was observed that: (i) 14bpDI genotype is a risk factor for HTLV-1 infection, while the 14bpDD and +3142CC genotypes were associated with protection against infection; (ii) the +3142C allele and the +3003CT and +3142CC genotypes were associated with susceptibility, while 14bpII and +3003TT genotypes were associated with protection against HAM/TSP development; and (iii) the 14bpII, +3010CC, +3142GG and +3187AA genotypes were associated with lower HTLV-1 proviral load compared to respective counterpart genotypes. Findings that HLA-G has a well-recognized immunomodulatory role and that the genetic variability at HLA-G 3'-UTR may post-transcriptionally modify HLA-G production indicate a differential genetic susceptibility to: (i) the development of HTLV-1 infection, (ii) the magnitude of HTLV-1 proviral load and (iii) HAM/TSP development.


Assuntos
Regiões 3' não Traduzidas , Antígenos HLA-G/genética , Infecções por HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Paraparesia Espástica Tropical/genética , Polimorfismo Genético , Provírus/fisiologia , Doenças da Medula Espinal/genética , Adolescente , Adulto , Idoso , Feminino , Predisposição Genética para Doença , Antígenos HLA-G/imunologia , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/virologia , Provírus/genética , Doenças da Medula Espinal/imunologia , Doenças da Medula Espinal/virologia , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-28050190

RESUMO

Bothrops jararaca (BJ) and Bothrops erythromelas (BE) are viper snakes found in South-Southeast and Northeast regions of Brazil, respectively. Snake venoms are bioactive neurotoxic substances synthesized and stored by venom glands, with different physiological and pharmacological effects, recently suggesting a possible preference for targets in cancer cells; however, mechanisms of snakes have been little studied. Here, we investigated the mechanism responsible for snake crude venoms toxicity in cultured cervical cancer cells SiHa and HeLa. We show that BJ and BE snake crude venoms exert cytotoxic effects to these cells. The percentage of apoptotic cells and cell cycle analysis and cell proliferation were assessed by flow cytometry and MTT assay. Detection of mitochondrial membrane potential (Rhodamine-123), nuclei morphological change, and DNA fragmentation were examined by staining with DAPI. The results showed that both the BJ and BE venoms were capable of inhibiting tumor cell proliferation, promoting cytotoxicity and death by apoptosis of target SiHa and HeLa cells when treated with BJ and BE venoms. Furthermore, data revealed that both BJ venoms in SiHa cell promoted nuclear condensation, fragmentation, and formation of apoptotic bodies by DAPI assay, mitochondrial damage by Rhodamine-123, and cell cycle block in the G1-G0 phase. BJ and BE venoms present anticancer potential, suggesting that both Bothrops venoms could be used as prototypes for the development of new therapies.

8.
PLoS One ; 8(10): e71742, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24204558

RESUMO

HLA-G molecule has well-recognized tolerogenic properties, and the encoding gene shows lower frequency of polymorphism at the coding region but higher variability at regulatory 5' and 3' untranslated (3'UTR) regions. At least three 3'UTR polymorphic sites have been associated with HLA-G mRNA regulation, including the 14 base pair (14bp) Insertion/Deletion, +3142C-G and +3187A-G. We studied the association of polymorphic sites at 3'UTR (sequencing analysis, encompassing the 14bp Ins-Del/+3003T-C/+3010C-G/+3027C-A/+3035C-T/+3142C-G/+3187A-G/+3196C-G polymorphic sites) with plasma soluble HLA-G levels (sHLA-G, detected by ELISA) in 187 French and 153 Brazilian healthy individuals. Allele and genotype frequencies were closely similar in both populations; however, Brazilians showed a higher HLA-G 3'UTR haplotype diversity. Considering sHLA-G levels in both populations altogether, individuals presenting 14bp Del/Del showed higher levels compared to 14bpIns/Ins genotype (P <0.05); those presenting +3010C/G showed higher levels compared to the +3010C-C genotype (P< 0.05); those presenting +3027C-C showed higher levels than the +3027A-A genotype (P< 0.05); and those bearing +3035C-C showed higher levels compared to the +3035C-T (P < 0.01) and +3035T-T (P < 0.05) genotypes. The analyses of 3'UTR haplotypes showed that UTR-1 (DelTGCCCGC) was associated with higher expression of sHLA-G, whereas UTR-5 (InsTCCTGAC) and UTR-7 (InsTCATGAC) with lower expression and other UTRs (UTR-2/3/4/6) exhibited intermediate levels. Since the differential expression of HLA-G may be beneficial or harmful depending on the underlying condition, the identification of individuals genetically programmed to differentially express HLA-G may help on defining novel strategies to control the immune response against the underlying disorder.


Assuntos
Regiões 3' não Traduzidas , Antígenos HLA-G/sangue , Antígenos HLA-G/genética , Polimorfismo Genético , Adulto , Alelos , Processamento Alternativo , Brasil , Feminino , França , Frequência do Gene , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas , Adulto Jovem
10.
Ann N Y Acad Sci ; 1150: 282-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120314

RESUMO

The MHC region (6p21) aggregates the major genes that contribute to susceptibility to type 1 diabetes (T1D). Three additional relevant susceptibility regions mapped on chromosomes 1p13 (PTPN22), 2q33 (CTLA-4), and 11p15 (insulin) have also been described by linkage studies. To evaluate the contribution of these susceptibility regions and the chromosomes that house these regions, we performed a large-scale differential gene expression on lymphomononuclear cells of recently diagnosed T1D patients, pinpointing relevant modulated genes clustered in these regions and their respective chromosomes. A total of 4608 cDNAs from the IMAGE library were spotted onto glass slides using robotic technology. Statistical analysis was carried out using the SAM program, and data regarding gene location and biological function were obtained at the SOURCE, NCBI, and FATIGO programs. Three induced genes were observed spanning around the MHC region (6p21-6p23), and seven modulated genes (5 repressed and 2 repressed) were seen spanning around the 6q21-24 region. Additional modulated genes were observed in and around the 1p13, 2q33, and 11p15 regions. Overall, modulated genes in these regions were primarily associated with cellular metabolism, transcription factors and signaling transduction. The differential gene expression characterization may identify new genes potentially involved with diabetes pathogenesis.


Assuntos
Diabetes Mellitus Tipo 1/genética , Perfilação da Expressão Gênica , Predisposição Genética para Doença/genética , Análise de Sequência com Séries de Oligonucleotídeos , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Mapeamento Cromossômico , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 6 , Análise por Conglomerados , Feminino , Frequência do Gene , Genes MHC da Classe II , Humanos , Masculino
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