Navegando por Orientadores "SANTOS, Ney Pereira Carneiro dos"

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Acesso aberto (Open Access)
Análise da expressão de miRNAs em carcinoma hepatocelular
(Universidade Federal do Pará, 2014-02-11) SANTOS, Ian Barroso dos; DEMACHKI, Samia; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/7568391537270652; http://lattes.cnpq.br/1290427033107137
Hepatocellular carcinoma represents the most common primary malignancy of the liver and the fifth most common solid tumor worldwide. Highly lethal, remais a serious public health problem because of difficulties in early diagnosis and the development of effective therapeutic measures. Recent in the field of molecular biology studies suggest that define the profile of miRNAs in hepatocellular carcinoma may considerably influence the identification of risk factors associated with oncogenes and suppressor genes. The objective is to evaluate the expression of miRNA 135b, miRNA 181a-5p and miRNA 181a-3p in samples of Hepatocellular Carcinoma and Chronic Hepatitis C and correlate them so likely to seek biomarkers related to the mechanism of carcinogenesis. The research was done in six patients with hepatocellular carcinoma and twenty four cases of Chronic Hepatitis C, Para, northen Brazil. All samples Hepatocellular carcinoma underwent microdissection for subsequent RNA extraction. For the extraction of total RNA and microRNA All=Prep the DNA / RNA FFPE kit (quiagem), quantified by the Qubit® 2.0 Fluorometer (Invitrogen) for final concentration of 5ng/μL standard equipment was used. The cDNA was obtained using TaqMan® MicroRNA Reverse Transcription (Applied Biosystems). Statistical analyzes were performed in softwares SPSS 17.0, using the Mann-Whitney test, with significat differences in the expression levels of the miR181a-3p and miR 181a-5p in hepatocellular carcinoma (average 3.94 and 17.9, respectively) compared with chronic hepatitis C (average 1.18 to 1.8, respectively) with P-value of 0.005 and 0.003. In this study, it was observed that miRNAs 181a-3p and 181a-5p, especially the 181a-5p way were significantly more highly expressed in hepatocellular carcinoma samples when compared to non-tumor liver tissue with chronic hepatitis C. Therefore, microRNAs have interesting characteristics that favor them as possible in biological screening for early diagnosis of tumors and targeted therapies selected markers.
Acesso aberto (Open Access)
Avaliação da toxicidade e correlação com polimorfismos no gene de reparo X-RCC1 em pacientes com neoplasias do trato gastrointestinal submetidos a radio e quimioterapia
(Universidade Federal do Pará, 2015-12-18) SOUZA, Paulo Gustavo Cavalcanti de; ASSUMPÇÃO, Paulo Pimentel de; http://lattes.cnpq.br/7323606327039876; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
The intestine tract neoplasms consist in an important problem of Brazil’s health as consequence of its incidence and mortality. Radiotherapy plays a fundamental work as part of gastric and rectal cancer treatment. The vastly background in radiobiology and the recently advances in the comprehension of molecular mechanisms involved in the behaviour of tumour cells and the normal tissues to ionizing radiation has been demonstrating the importance of repair DNA genes. The gene XRCC-1 plays an important work repairing ionizing lesions, working in the answers of single strand break through repairing by base excision. XRCC-1 base polymorphisms can influence the answer of radiotherapy’s answer, in the same way the toxicity showed on them. In the present study we analysed the toxicity of gastric and rectal cancer patients submitted to radiation treatment and chemotherapy and its relation with the occurrence of specifics polymorphisms of XRCC-1 GENE, C194T (rs1799782) and INDEL 4 bp GGCC (rs3213239). Our data showed a general toxicity rate of 64,5 %, but only 24,5 % were grade 3 or 4. The specific toxicity grade 3 or 4 rate were 16,3 % diarrhea, 6 % dermatitis and 6 % nausea. We did not find and correlation between the polymorphisms C194T (rs1799782) and INDEL (rs1799782) and the rate of toxicity found, except when we evaluated patients with gastric and rectal cancer separately. In the latter group, the allele T of C194T was associated with a higher incidence of nausea, with a 10,5 fold risk and a p value of 0,03. Although this positive correlation, we believe that the number of patients in our study was insufficient to a more accurate correlation between toxicity and polymorphisms.
Acesso aberto (Open Access)
Avaliação do polimorfismo INDEL no gene TYMS em associação a resposta quanto ao uso de fluoropirimidinas em pacientes portadores de neoplasias do trato gastrointestinal
(Universidade Federal do Pará, 2014-02-26) COSTA, Danielle Feio da; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
Cancer is a public health problem worldwide, with an estimated of 27 million new cases and 17 million cancer deaths in 2030. In Brazil, estimates for cancer in 2014, indicate the occurrence of approximately 580 000 new cases. Fluoropyrimidines are used in the main chemotherapy regimens targeted to tumors of the gastrointestinal tract. Recently, much has been investigated on causes of different individual responses to chemotherapy.Thus, it has been sought an individualized therapy that can maximize drug efficacy and minimize adverse effects associated with drugs. We aimed to seek the association of an INDEL polymorphism (rs16430) in TYMS gene with the pattern of response to chemotherapy drugs based on fluoropyrimidines, in order to contribute to the development of personalized medicine. We studied 151 samples of cancer patients treated with fluoropyrimidine, from a population of the Brazilian Amazon region with high interethnic admixture. An INDEL polymorphism (rs16430) was genotyped in TYMS gene that is involved in the response to treatment using fluoropyrimidines. The research reported that most patients had advanced disease at diagnosis, of which 32.7% were treated with palliative intent, and 22.8% neoadjuvant treatment. Our results show that the INDEL polymorphism in the TYMS gene appears to have a protective effect on tumor progression (p = 0.033). Patients treated with fluoropyrimidine who were wild homozygous (INS / INS) had a 24% protection to tumor progression compared to other genotypes of this polymorphism. Estimates of global genetic ancestry of the sample investigated were: 62.4% European, 25.2% Amerindian and 12.4% African. It was possible to establish an inverse correlation between the increase of Amerindian ancestry and metastasis (p = 0.024). Pharmacogenetic studies can provide a personalized therapy toxicity reducing mortality and improving therapeutic efficacy, thereby providing a cancer therapy with better clinical results.
Acesso aberto (Open Access)
Farmacogenética do Gene TPMT na resposta A 6-Mercaptopurina, em pacientes com Leucemia Linfoblástica Aguda
(Universidade Federal do Pará, 2016-03-03) LIMA, Carlos Henrique Vasconcelos de; ASSUMPÇÃO, Paulo Pimentel de; http://lattes.cnpq.br/7323606327039876; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
Acute Lymphoblastic Leukemia (ALL) is the most common type of cancer in children under 15 years of age. 6-mercaptopurine (6-MP) is one of the most widely used chemotherapeutic agents in the treatment of childhood ALL. Polymorphisms in thiopurine S-methyltransferase gene (TPMT) may be associated with individual variation in the response to treatment of childhood ALL, such as increased severe toxicity (grade 3 and 4). The aim of this study was to associate polymorphisms of TPMT gene: TPMT*2 (238G>C), TPMT*3A (460G>A and 719A>G), TPMT*3B (460G>A), TPMT*3C (719A>G), TPMT* 8 (644G>A) and intronic variant rs12201199 (94T>A) with the occurrence of serious toxicities in patients with ALL treated with 6-MP, in Northern Brazil. One hundred thirty-seven pediatric patients with ALL and treated at the Ophir Loyola Hospital in the state of Pará were investigated. The rs12201199 polymorphism was genotyped by real-time PCR (equipment 7500 Real-Time PCR System) and other polymorphisms were genotyped by direct sequencing using the automated sequencer ABI PRISM 3130 Genetic Analyzer (Applied Biosytems, CA, USA). The haplotypes among the studied polymorphisms were derived via maximum likelihood estimates using the program PHASE. A panel of 48 markers Ancestry Informative was used as genomic control in the sample and statistical analyses were performed using SPSS v.20.0 software (SPSS, Chicago, IL, USA). All statistical tests considered the probability (p) significant when ≤0, 05. In relation to the genomic ancestry, it was noted that the ethnic composition of ALL patients was 44% Caucasian, 22% African and 34% Amerindian. Among the reported toxicities, infectious was most prevalent (86%), followed by hematological (65%), gastrointestinal (64.8%) and central nervous system toxicity (29.9%). Allele frequency of polymorphism rs12201199 was 0.482 among the studied subjects. The most prevalent haplotype variants were TPMT*3A (7.6%), followed by TPMT*3C and TPMT*8, both 7.3%. There was no significant association between poor metabolism profiles of TPMT with none of the serious toxicities reported in the studied patients with LLA. However, our data show that there is a significant relationship between the polymorphism of TPMT gene (rs12201199) and the occurrence of severe infectious toxicity during treatment of childhood ALL. It has been observed that patients who have mutant homozygous AA genotype for this polymorphism in TPMT gene have 4.098 times higher risk of presenting severe infectious toxicity during the treatment for childhood ALL compared to those with the other genotypes. This result may be important to help predict risk of toxicity during treatment, contributing to a better individual prognosis of patients with childhood ALL.
Acesso aberto (Open Access)
Investigação de polimorfismos nos genes XRCC1, MTHFR e EGFR como possíveis marcadores de suscetibilidade ao câncer, na população de Belém-PA
(Universidade Federal do Pará, 2013-04-08) VIEIRA, Priscilla Cristina Moura; BURBANO, Rommel Mario Rodriguéz; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/4362051219348099; http://lattes.cnpq.br/1290427033107137
Cancer is defined as a multifactorial disease resulting from complex interactions between extrinsic and intrinsic factors. Among the main intrinsic factors are the genetic and/or epigenetic alterations in genes involved with the carcinogenesis process. The identification and characterization of these genes may provide a better understanding of the molecular basis of cancer. Considering the importance of alterations in XRCC1, MRHFR and EGFR genes in various pro-carcinogenic pathways, it is extremely important to investigate the effects of functional polymorphisms in these genes and their molecular consequences in cancer susceptibility.The objective of this study was to identify possible associations between single nucleotide polymorphisms (SNPs) Arg194Trp (XRCC1) e Ala222Val (MTHFR) e Arg521Lys (EGFR) with the development of gastric and breast cancers in the population of Belém-PA, in a case-control study. Furthermore, the control of genomic ancestry was held to avoid spurious results arising from population substructuring in the groups investigated. Molecular analysis of SNPs was carried out by TaqMan. Statistical analyses were performed using the program SPSS v.20 and to estimate the interethnic admixture we used the program STRUCTURE v.2.2. Regarding polymorphisms Arg194Trp, Ala222Val we did not observe any significant association with susceptibility to breast and gastric tumors (P > 0.05).For the polymorphism Arg521Lys, in a first moment (univariate analysis), a significant effect for susceptibility to cancers investigated was found (P = 0.037). However, after genomic control for African and European ancestries, this result has proved to be spurious (P = 0.064). Regarding ancestries, our results showed a strong association of African ancestry with susceptibility to gastric and breast cancers (P = 0.010, OR = 76,723; 95% CI = 2.805 - 2098.230) whereas for European contribution a protective effect was found (P = 0.024, OR = 0071, 95% CI = 0.007-0.703). In conclusion, our study presented the evidence that the African and European genomic ancestries are important factors related to susceptibility to gastric and breast cancers. Regarding Arg521Ly polymorphism, further studies are necessary to confirm whether the association is indeed spurious.
Acesso aberto (Open Access)
Perfil molecular em genes cyp3a4 e cyp2j2: um caminho para a farmacogenética do Rivaroxaban em uma população do Norte do Brasil
(Universidade Federal do Pará, 2014-01-23) TOSCANO, Paulo Martins; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
In recent years, new anticoagulants have been developed with the purpose of minimizing the difficulties encountered in the clinical management of conventional dru- gs, but there are no published data on its pharmacogenetics. Considering the hypothe- sis that polymorphisms related to its metabolism may be the source of genetic variability, this study aims to make inferences on molecular epidemiology of polymorphisms in CyP3a4 (rs2246709) and CyP2j2 (rs890293) genes related to the metabolism of Rivaroxaban, a new direct factor Xa inhibitor. 136 samples from healthy individuals in a population of northern Brazil with a high degree of inter-ethnic mix, so as to guarantee that the pharmacogenetic goal was achieved, have been subjected to a parallel analysis of genomic ancestry for the individuals investigated. The results sho- wed significant differences among genotypes for CyP3a4 observed in the study com- pared to all ancestral populations for a polymorphism 99,365,719 a> G ( P < 0.05). The mixed population of northern Brazil, therefore, showed differences in the distribution of genotype frequencies in relation to ancestral groups, forming our population. The same finding was not observed for the CyP2j2 gene polymorphism. It is noteworthy that the polymorphism in the CyP3a4 gene in the investigated sample is influenced by indivi- dual ethnic European contribution. Considering the high miscegenation featuring local people, and the advancement of Pharmacogenomics in current medicine, such data can contribute to a better understanding of the pharmacogenetics of that new anticoagulant.
Acesso aberto (Open Access)
Variabilidade do gene CYP2D6 em populações ameríndias
(Universidade Federal do Pará, 2018-12-03) LEITÃO, Luciana Pereira Colares; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
The genetic cytochrome P450 superfamily is of significant relevance to the process of metabolizing drugs in the human liver. The CYP2D6 gene, one of the most studied genes due to its vast amount of genomic variations and the low influence of external non-genetic factors that affect the metabolization process of more than 20% of the drugs marketed. The molecular profile of the CYP2D6 gene influences several classes of drugs: antidepressants, antipsychotics, antiarrhythmics, opioid analgesics, anticancer agents among other drugs. However, these protocols are designed mainly for populations of European origin, not being properly employed in Brazilian populations, as are results from a complex process of miscegenation involving the contribution mainly from European, African and Amerindian. Pharmacogenomic studies in Amerindian populations are scarce. Thus, in the absence of consistent data, the establishment of public health policies aimed at the implementation of precision medicine in these populations, and in peoples mixed with these ethnic groups, is impaired. Genomic studies capable of analyzing the genetic heterogeneity of biomarkers associated with the metabolism process of several drugs in Amerindian and mixed populations are of great scientific impact. Based on this study evaluated the molecular profile 22 therapy important predictors of the CYP2D6 gene polymorphisms in individuals in American Indians Amazon samples from three tribes: the Asurini Trocará, Asurini Koatinemo and the Kayapo-Xikrin. The DNA was extracted from the peripheral blood of the individuals studied. Polymorphism genotypes were performed by Taqman® assays in OpenArray® on the QuantStudio ™ 12K Flex Real-Time PCR System. The statistical analyses was due in the programs Arlequin v. 3.5.2.2, SPSS v. 12.0 and the statistical package of R. In addition to this original work, a review was carried out to group CYP2D6 gene data in other Amerindian populations. From the results it was possible to observe that the normal extensive metabolism profile is the most frequent in the Amerindian population of the review and in the Brazilian Amazon Amerindian population. The profiles of clinical importance, slow and ultrafast, presented low frequency in the populations of the review and was not observed in the Amazonian population. These data may infer that the Amerindian population may have some protection from drug-related adverse effects and drug failure that are metabolized by CYP2D6.