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2.
Cancer Med ; 13(3): e6729, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38308422

RESUMO

BACKGROUND: Approximately 3/4 of ovarian cancers are diagnosed in advanced stages, with the high-grade epithelial ovarian carcinoma (EOC) accounting for 90% of the cases. EOC present high genomic instability and somatic loss-of-function variants in genes associated with homologous recombination mutational repair pathway (HR), such as BRCA1 and BRCA2, and in TP53. The identification of germline variants in HR genes in EOC is relevant for treatment of platinum resistant tumors and relapsed tumors with therapies based in synthetic lethality such as PARP inhibitors. Patients with somatic variants in HR genes may also benefit from these therapies. In this work was analyzed the frequency of somatic variants in BRCA1, BRCA2, and TP53 in an EOC cohort of Brazilian patients, estimating the proportion of variants in tumoral tissue and their association with progression-free survival and overall survival. METHODS: The study was conducted with paired blood/tumor samples from 56 patients. Germline and tumoral sequences of BRCA1, BRCA2, and TP53 were obtained by massive parallel sequencing. The HaplotypeCaller method was used for calling germline variants, and somatic variants were called with Mutect2. RESULTS: A total of 26 germline variants were found, and seven patients presented germline pathogenic or likely pathogenic variants in BRCA1 or BRCA2. The analysis of tumoral tissue identified 52 somatic variants in 41 patients, being 43 somatic variants affecting or likely affecting protein functionality. Survival analyses showed that tumor staging was associated with overall survival (OS), while the presence of somatic mutation in TP53 was not associated with OS or progression-free survival. CONCLUSION: Frequency of pathogenic or likely pathogenic germline variants in BRCA1 and BRCA2 (12.5%) was lower in comparison with other studies. TP53 was the most altered gene in tumors, with 62.5% presenting likely non-functional or non-functional somatic variants, while eight 14.2% presented likely non-functional or non-functional somatic variants in BRCA1 or BRCA2.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Carcinoma Epitelial do Ovário/genética , Brasil/epidemiologia , Neoplasias Ovarianas/genética , Reparo do DNA , Células Germinativas , Proteína Supressora de Tumor p53/genética , Proteína BRCA1/genética , Proteína BRCA2/genética
4.
Rev Bras Ginecol Obstet ; 45(8): e474-e479, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37683659

RESUMO

OBJECTIVE: Similar to Human Papillomavirus (HPV) genotypes, different lineages of a genotype also have different carcinogenic capabilities. Studies have shown that specific genotype lineages of oncogenic HPV are associated with variable risks for the development of cervical intraepithelial neoplasia (CIN2/CIN3) and cervical cancer. The present study aimed to analyze the genetic diversity of the HPV16 genotype in women with CIN2/CIN3 and cervical cancer, from the northeast region of Brazil. METHODS: A cross-sectional multicenter study was conducted in the northeast region of Brazil, from 2014 to 2016. This study included 196 cases of HPV16 variants (59 and 137 cases of CIN2/CIN3 and cervical cancer, respectively). The difference of proportion test was used to compare patients with CIN2/CIN3 and cervical cancer, based on the prevalent HPV16 lineage (p < 0.05). RESULTS: According to the histopathological diagnosis, the percentage of lineage frequencies revealed a marginal difference in the prevalence of lineage A in CIN2/CIN3, compared with that in cervical cancer (p = 0.053). For lineage D, the proportion was higher in cancer cases (32.8%), than in CIN2/CIN3 cases (16.9%), with p = 0.023. CONCLUSION: HPV16 lineage A was the most frequent lineage in both CIN2/CIN3 and cervical cancer samples, while lineage D was predominant in cervical cancer, suggesting a possible association between HPV16 lineage D and cervical cancer.


OBJETIVO: Tanto os tipos quanto as linhagens do Papilomavírus Humano (HPV) parecem ter diferentes capacidades carcinogênicas e estão associados a riscos variados para o desenvolvimento de neoplasia intraepitelial cervical (NIC) e câncer de colo do útero. O presente estudo tem como objetivo analisar a diversidade genética do genótipo HPV 16 nos casos de NIC2/NIC3 e câncer de colo de útero em mulheres da região Nordeste do Brasil. MéTODOS: Estudo transversal de base hospitalar realizado na região Nordeste do Brasil no período de 2014 a 2016. A amostra foi composta por 196 casos da variante HPV-16 (59 casos de NIC2/NIC3 e 137 de câncer do colo do útero). O teste de diferença de proporção foi usado para comparar os grupos NIC2/NIC3 e câncer de colo do útero por linhagem viral em relação à prevalência da linhagem HPV-16. Foi considerada significância estatística o valor de p < 0,05. RESULTADOS: As frequências de linhagem por diagnóstico histopatológico mostraram diferença limítrofe da linhagem A no grupo NIC2/NIC3 em relação ao grupo câncer de colo de útero (p = 0,053). Por outro lado, em relação à linhagem D, houve uma proporção maior nos casos de câncer (32,8%) quando comparado ao grupo NIC2/NIC3 (16,9%) e esta diferença se mostrou estatisticamente significante (p = 0,023). CONCLUSãO: A linhagem A do HPV-16 foi a mais frequente tanto nas amostras CIN2/CIN3 quanto nas amostras de câncer de colo de útero, enquanto a linhagem D predominou no câncer de colo do útero, sugerindo uma possível associação da linhagem D de HPV-16 com câncer de colo de útero.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/epidemiologia , Brasil/epidemiologia , Papillomavirus Humano , Estudos Transversais , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Papillomaviridae
5.
Int J Mol Sci ; 24(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239905

RESUMO

CD59 is an abundant immuno-regulatory human protein that protects cells from damage by inhibiting the complement system. CD59 inhibits the assembly of the Membrane Attack Complex (MAC), the bactericidal pore-forming toxin of the innate immune system. In addition, several pathogenic viruses, including HIV-1, escape complement-mediated virolysis by incorporating this complement inhibitor in their own viral envelope. This makes human pathogenic viruses, such as HIV-1, not neutralised by the complement in human fluids. CD59 is also overexpressed in several cancer cells to resist the complement attack. Consistent with its importance as a therapeutical target, CD59-targeting antibodies have been proven to be successful in hindering HIV-1 growth and counteracting the effect of complement inhibition by specific cancer cells. In this work, we make use of bioinformatics and computational tools to identify CD59 interactions with blocking antibodies and to describe molecular details of the paratope-epitope interface. Based on this information, we design and produce paratope-mimicking bicyclic peptides able to target CD59. Our results set the basis for the development of antibody-mimicking small molecules targeting CD59 with potential therapeutic interest as complement activators.


Assuntos
Proteínas do Sistema Complemento , HIV-1 , Humanos , Sítios de Ligação de Anticorpos , Proteínas do Sistema Complemento/metabolismo , Antígenos CD59/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Inativadores do Complemento , HIV-1/fisiologia
6.
Rev. bras. ginecol. obstet ; 45(8): 474-479, 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1515062

RESUMO

Abstract Objective Similar to Human Papillomavirus (HPV) genotypes, different lineages of a genotype also have different carcinogenic capabilities. Studies have shown that specific genotype lineages of oncogenic HPV are associated with variable risks for the development of cervical intraepithelial neoplasia (CIN2/CIN3) and cervical cancer. The present study aimed to analyze the genetic diversity of the HPV16 genotype in women with CIN2/CIN3 and cervical cancer, from the northeast region of Brazil. Methods A cross-sectional multicenter study was conducted in the northeast region of Brazil, from 2014 to 2016. This study included 196 cases of HPV16 variants (59 and 137 cases of CIN2/CIN3 and cervical cancer, respectively). The difference of proportion test was used to compare patients with CIN2/CIN3 and cervical cancer, based on the prevalent HPV16 lineage (p < 0.05). Results According to the histopathological diagnosis, the percentage of lineage frequencies revealed a marginal difference in the prevalence of lineage A in CIN2/CIN3, compared with that in cervical cancer (p = 0.053). For lineage D, the proportion was higher in cancer cases (32.8%), than in CIN2/CIN3 cases (16.9%), with p = 0.023. Conclusion HPV16 lineage A was the most frequent lineage in both CIN2/CIN3 and cervical cancer samples, while lineage D was predominant in cervical cancer, suggesting a possible association between HPV16 lineage D and cervical cancer.


Resumo Objetivo Tanto os tipos quanto as linhagens do Papilomavírus Humano (HPV) parecem ter diferentes capacidades carcinogênicas e estão associados a riscos variados para o desenvolvimento de neoplasia intraepitelial cervical (NIC) e câncer de colo do útero. O presente estudo tem como objetivo analisar a diversidade genética do genótipo HPV 16 nos casos de NIC2/NIC3 e câncer de colo de útero em mulheres da região Nordeste do Brasil. Métodos Estudo transversal de base hospitalar realizado na região Nordeste do Brasil no período de 2014 a 2016. A amostra foi composta por 196 casos da variante HPV-16 (59 casos de NIC2/NIC3 e 137 de câncer do colo do útero). O teste de diferença de proporção foi usado para comparar os grupos NIC2/NIC3 e câncer de colo do útero por linhagem viral em relação à prevalência da linhagem HPV-16. Foi considerada significância estatística o valor de p < 0,05. Resultados As frequências de linhagem por diagnóstico histopatológico mostraram diferença limítrofe da linhagem A no grupo NIC2/NIC3 em relação ao grupo câncer de colo de útero (p = 0,053). Por outro lado, em relação à linhagem D, houve uma proporção maior nos casos de câncer (32,8%) quando comparado ao grupo NIC2/NIC3 (16,9%) e esta diferença se mostrou estatisticamente significante (p = 0,023). Conclusão A linhagem A do HPV-16 foi a mais frequente tanto nas amostras CIN2/CIN3 quanto nas amostras de câncer de colo de útero, enquanto a linhagem D predominou no câncer de colo do útero, sugerindo uma possível associação da linhagem D de HPV-16 com câncer de colo de útero.


Assuntos
Humanos , Feminino , Papillomavirus Humano 16
7.
Viruses ; 14(12)2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36560657

RESUMO

The APOBEC3 (A3) proteins are cytidine deaminases that exhibit the ability to insert mutations in DNA and/or RNA sequences. APOBEC3B (A3B) has been evidenced as a DNA mutagen with consistent high expression in several cancer types. Data concerning the A3B influence on HPV infection and cervical cancer are limited and controversial. We investigated the role of A3B expression levels in cervical cancer in affected women positive for infection by different HPV types. Tumor biopsies from cancerous uterine cervix were collected from 216 women registered at Hospital do Câncer II of Instituto Nacional de Câncer, and infecting HPV was typed. A3B expression levels were quantified from RNA samples extracted from cervical biopsies using real-time quantitative PCR. Median A3B expression levels were higher among HPV18+ samples when compared to HPV16+ counterparts and were also increased compared to samples positive for other HPV types. In squamous cell carcinoma, HPV18+ samples also showed increased median A3B expression when compared to HPV Alpha-9 species or only to HPV16+ samples. Our findings suggest that A3B expression is differentially upregulated in cervical cancer samples infected with HPV18. A3B could be potentially used as a biomarker for HPV infection and as a prognostic tool for clinical outcomes in the context of cervical cancer.


Assuntos
Citidina Desaminase , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Citidina Desaminase/genética , DNA , Papillomavirus Humano 18 , Antígenos de Histocompatibilidade Menor/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , RNA Mensageiro/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia
8.
Sci Rep ; 12(1): 18629, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329109

RESUMO

Several studies have demonstrated the cost-effectiveness of genetic testing for surveillance and treatment of carriers of germline pathogenic variants associated with hereditary breast/ovarian cancer syndrome (HBOC). In Brazil, seventy percent of the population is assisted by the public Unified Health System (SUS), where genetic testing is still unavailable. And few studies were performed regarding the prevalence of HBOC pathogenic variants in this context. Here, we estimated the prevalence of germline pathogenic variants in BRCA1, BRCA2 and TP53 genes in Brazilian patients suspected of HBOC and referred to public healthcare service. Predictive power of risk prediction models for detecting mutation carriers was also evaluated. We found that 41 out of 257 tested patients (15.9%) were carriers of pathogenic variants in the analyzed genes. Most frequent pathogenic variant was the founder Brazilian mutation TP53 c.1010G > A (p.Arg337His), adding to the accumulated evidence that supports inclusion of TP53 in routine testing of Brazilian HBOC patients. Surprisingly, BRCA1 c.5266dupC (p.Gln1756fs), a frequently reported pathogenic variant in Brazilian HBOC patients, was not observed. Regarding the use of predictive models, we found that familial history of cancer might be used to improve selection or prioritization of patients for genetic testing, especially in a context of limited resources.


Assuntos
Neoplasias da Mama , Síndromes Neoplásicas Hereditárias , Neoplasias Ovarianas , Feminino , Humanos , Brasil/epidemiologia , Prevalência , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/diagnóstico , Predisposição Genética para Doença , Proteína BRCA2/genética , Proteína BRCA1/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Carcinoma Epitelial do Ovário , Atenção à Saúde , Mutação em Linhagem Germinativa , Proteína Supressora de Tumor p53/genética
9.
Front Microbiol ; 13: 1074382, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713167

RESUMO

Due to immunosuppressive cancer therapies, cancer patients diagnosed with COVID-19 have a higher chance of developing severe symptoms and present a higher mortality rate in comparison to the general population. Here we show a comparative analysis of the microbiome from naso-oropharyngeal samples of breast cancer patients with respect to SARS-CoV-2 status and identified bacteria associated with symptom severity. Total DNA of naso-oropharyngeal swabs from 74 women with or without breast cancer, positive or negative for SARS-CoV-2 were PCR-amplified for 16S-rDNA V3 and V4 regions and submitted to massive parallel sequencing. Sequencing data were analyzed with QIIME2 and taxonomic identification was performed using the q2-feature-classifier QIIME2 plugin, the Greengenes Database, and amplicon sequence variants (ASV) analysis. A total of 486 different bacteria were identified. No difference was found in taxa diversity between sample groups. Cluster analysis did not group the samples concerning SARS-CoV-2 status, breast cancer diagnosis, or symptom severity. Three taxa (Pseudomonas, Moraxella, and Klebsiella,) showed to be overrepresented in women with breast cancer and positive for SARS-CoV-2 when compared to the other women groups, and five bacterial groups were associated with COVID-19 severity among breast cancer patients: Staphylococcus, Staphylococcus epidermidis, Scardovia, Parasegitibacter luogiensis, and Thermomonas. The presence of Staphylococcus in COVID-19 breast cancer patients may possibly be a consequence of nosocomial infection.

10.
Exp Eye Res ; 211: 108753, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34478740

RESUMO

Retinoblastoma is the most common malignant ocular tumor in children. Although RB1 alterations are most frequently involved in the etiology of retinoblastoma, candidate driver events and somatic alterations leading to cell transformation, tumor onset and progression remain poorly understood. In this study, we identified novel genomic alterations in tumors with a panel of 160 genes. Sanger sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA) were initially performed for identifying patients without apparent RB1 alterations in blood DNA. Subsequently, NGS analyses of 24 paired (blood/tumor) samples of these patients were carried out for identifying somatic mutations and copy number variation in RB1 and other 159 genes. One novel pathogenic RB1 mutation and seven novel VUS were identified as well as 90 novel pathogenic mutations in 61 other genes. Twenty-three genes appeared exclusively mutated in tumors without altered RB1 alleles and three frequently affected biological pathways while five other tumors did not show pathogenic RB1 alterations or SNV/indels in 159 other genes. Curiously, deletion of GATA2, AKT1, ARID1A, DNMT3A, MAP2K2, MEN1, MTOR, PTCH1 and SUFU (in homo- or heterozygosity) were exclusively found in these tumors when compared to those with any pathogenic alterations, probably indicating genes that might be essential for the development of retinoblastoma regardless of a functional RB1. Identification of genes associated with retinoblastoma will contribute to understanding presently unknown aspects of this malignancy, which might be essential for its initiation and progression, as well as providing valuable molecular markers.


Assuntos
Genes Neoplásicos/genética , Mutação , Proteínas de Neoplasias/genética , Neoplasias da Retina/genética , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Alelos , Pré-Escolar , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Lactente , Masculino , Biologia Molecular , Reação em Cadeia da Polimerase Multiplex , Análise de Sequência de DNA
11.
Cancers (Basel) ; 13(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34298727

RESUMO

Retroelements are expressed in diverse types of cancer and are related to tumorigenesis and to cancer progression. We characterized the expression of retroelements in cervical cancer and explored their interplay with HPV infection and their association with expression of neighboring genes. Forty biopsies of invasive cervical carcinoma (squamous cell carcinomas and adenocarcinomas) with genotyped HPV were selected and analyzed for human endogenous retrovirus (HERV) and long interspersed nuclear element 1 (L1) expression through RNA-seq data. We found 8060 retroelements expressed in the samples and a negative correlation of DNA methyltransferase 1 expression with the two most expressed L1 elements. A total of 103 retroelements were found differentially expressed between tumor histological types and between HPV types, including several HERV families (HERV-K, HERV-H, HERV-E, HERV-I and HERV-L). The comparison between HPV mono- and co-infections showed the highest proportion of differentially expressed L1 elements. The location of retroelements affected neighboring gene expression, such as shown for the interleukin-20 gene family. Three HERVs and seven L1 were located close to this gene family and two L1 showed a positive association with IL20RB expression. This study describes the expression of retroelements in cervical cancer and shows their association with HPV status and host gene expression.

12.
Int J Biol Macromol ; 182: 1455-1462, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015405

RESUMO

CD55 is a major regulator of the complement system, a complex network of proteins that cooperate to clear tissue and blood pathogens from the organism. Indeed, overexpression of CD55 is associated with many diseases and is connected to the resistance mechanisms exhibited by several cancers towards immunotherapy approaches. High level of CD55 expression on tumour cells renders it a good target for both imaging and immunotherapy. Indeed, a conceivable approach to tackle disease is to interfere with CD55-mediated complement regulation with the use of CD55-targeting antibodies. However, the large size and poor tissue penetration together with to the high costs of antibodies often limits their widespread therapeutic use. Here, we employed bioinformatic and chemical approaches to design and synthesize molecules of small dimensions able to mimic a CD55 blocking antibody. As a result, a bicyclic peptide, named as miniAB55, proved to bind CD55 with nanomolar affinity. This molecule represents an attracting chemical scaffold for CD55-directed diagnostic tools in diseases associated with CD55 overproduction. To further support the applicative potential of miniAB55, we prove that the miniAB55 binds CD55 on the same region involved in inactivation of the complement C3 and C5 convertases, thus opening promising scenarios for the development of complement-modulating tools.


Assuntos
Anticorpos/farmacologia , Antígenos CD55/imunologia , Miniaturização , Peptídeos Cíclicos/química , Sequência de Aminoácidos , Sítios de Ligação de Anticorpos/imunologia , Antígenos CD55/química , Ciclização , Humanos , Cinética , Modelos Moleculares , Simulação de Acoplamento Molecular
13.
Breast Cancer Res Treat ; 185(3): 851-861, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33128190

RESUMO

PURPOSE: This study aimed to identify and classify genetic variants in consensus moderate-to-high-risk predisposition genes associated with Hereditary Breast and Ovarian Cancer Syndrome (HBOC), in BRCA1/2-negative patients from Brazil. METHODS: The study comprised 126 index patients who met NCCN clinical criteria and tested negative for all coding exons and intronic flanking regions of BRCA1/2 genes. Multiplex PCR-based assays were designed to cover the complete coding regions and flanking splicing sites of six genes implicated in HBOC. Sequencing was performed on HiSeq2500 Genome Analyzer. RESULTS: Overall, we identified 488 unique variants. We identified five patients (3.97%) that harbored pathogenic or likely pathogenic variants in four genes: ATM (1), CHEK2 (2), PALB2 (1), and TP53 (1). One hundred and thirty variants were classified as variants of uncertain significance (VUS), 10 of which were predicted to disrupt mRNA splicing (seven non-coding variants and three coding variants), while other six missense VUS were classified as probably damaging by prediction algorithms. CONCLUSION: A detailed mutational profile of non-BRCA genes is still being described in Brazil. In this study, we contributed to filling this gap, by providing important data on the diversity of genetic variants in a Brazilian high-risk patient cohort. ATM, CHEK2, PALB2 and TP53 are well established as HBOC predisposition genes, and the identification of deleterious variants in such actionable genes contributes to clinical management of probands and relatives.


Assuntos
Neoplasias da Mama , Síndrome Hereditária de Câncer de Mama e Ovário , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Consenso , Feminino , Predisposição Genética para Doença , Células Germinativas , Mutação em Linhagem Germinativa , Síndrome Hereditária de Câncer de Mama e Ovário/epidemiologia , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Humanos , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Prevalência
14.
BMC Womens Health ; 20(1): 162, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738888

RESUMO

BACKGROUND: Cervical cancer is the fourth most common type of cancer affecting women globally. In Brazil, it is the third most frequent type of cancer in women and HPV is present in approximately 90% of cases. Evidence suggests that variants of HPV 16 can interfere biologically and etiologically during the development of cervical cancer. METHODS: Cervix tumor fragments were collected, their DNA was extracted, and nested PCR was used to detect HPV. Positive samples were sequenced to determine the viral genotype. To characterize the HPV 16 strains, positive samples PCR was used to amplify the LCR and E6 regions of the HPV 16 virus. RESULTS: Data from 120 patients with cervical cancer were analyzed. Most women were between 41 and 54 years of age, had schooling until primary school, a family income between 1 and 2 times the minimum wage and were married/in a consensual union. There was no statistically significant association between HPV or socio-demographic variables and risk factors for cervical cancer (P <  0.05). HPV was present in 88 women (73%). The most prevalent types were HPV 16 (53.4%), HPV 18 (13.8%), HPV 35 (6.9%) and HPV 45 (5.7%). Of the 47 HPV 16 positive cases, variant A (49%) was present in 23 samples, followed by variant D in 20 cases (43%), and variants B and C in 2 cases each (4%). The most prevalent histological type of HPV 16 tumors was squamous cell carcinoma, followed by adenocarcinoma. There was a statistically significant association between HPV 16 variants and the tumors' histological types (P <  0.001). CONCLUSIONS: Knowledge of HPV 16 variants will provide data on their influence on the pathological and oncogenic aspects of cervical lesions.


Assuntos
DNA Viral/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Variação Genética , Papillomavirus Humano 16/classificação , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia
15.
Genet Mol Biol ; 43(2): e20190072, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453342

RESUMO

Specific pathogenic mutations associated with breast cancer development can vary between ethnical groups. One example is BRCA1 c.5266dupC that was first described as a founder mutation in the Ashkenazi Jewish population, but was later also found in other populations. In Brazil, this mutation corresponds to 20% of pathogenic BRCA1 variants reported. Our objective was to investigate the haplotype component of a group of Brazilian families who inherited c.5266dupC in the BRCA1 gene and to verify the ancestry contribution from European, African, and Amerindian origins. Fourteen probands carrying c.5266dupC and 16 relatives (carriers and non-carriers) were investigated. The same haplotype was observed segregating within all the families analyzed, revealing no recombinants in a region of 0.68 Mb. Ancestry analysis demonstrated that the European component was predominant among probands. The BRCA1 c.5266dupC analysis indicates that there was a founder effect in the Brazilian population.

16.
Int J Cancer ; 146(3): 731-738, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30963559

RESUMO

HPV73 is classified as possibly oncogenic. It is neither routinely evaluated in HPV screening, nor covered by any of the prophylactic vaccines. We sought to investigate the carcinogenic characteristics of HPV73. Molecular studies were performed on eight cervix cancer biopsy specimens containing HPV73 from a cross-sectional cancer cohort of 590 women referred to the National Cancer Institute in Rio de Janeiro, Brazil. Transcriptional activity of HPV73 was evaluated by detection of spliced transcripts of E6/E6* and E1^E4 in cDNA created from RNA isolated from fresh tissue. Disruption of viral E1 and E2 genes in the tumor DNA was assessed by overlapping PCR amplification. Evaluation of viral integration was performed using a customized capture panel and next-generation sequencing, and an in-house bioinformatic pipeline. HPV73 E6/E6* transcripts were found in 7/7 specimens with available RNA, and three also had HPV73 E1^E4 transcripts. Disruption of E1 and E2 genes was observed in 4/8 specimens. Integration of HPV73 sequences into the cancer cell genomes was identified in all cervix cancer tissues. These results provide evidence that HPV73 is an oncogenic virus that can cause invasive cervix cancer. With current molecular screening and HPV vaccination, not all cervix cancers will be prevented.


Assuntos
Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Brasil , Estudos Transversais , DNA de Neoplasias/genética , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/genética , Integração Viral/genética
17.
J Med Virol ; 92(8): 1283-1289, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31696949

RESUMO

INTRODUCTION: The human papillomavirus (HPV) E5 gene encodes a small and highly hydrophobic oncoprotein that affects immune evasion, cell proliferation, loss of apoptotic capacity and angiogenesis in tumors. E5 shows an affinity for biological membranes and was associated with an increase of epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) signaling through the accumulation of EGFR in cellular membranes. Due to the frequent integration of the HPV genome into the host cell genome, E5 is frequently not transcribed in cervical tumors. AIM: In this study we looked forward to verifying whether the potential expression of E5 protein in human papillomavirus 16 positive (HPV16+ ) and human papillomavirus 18 positive (HPV18+ ) cervical tumors was associated with levels of EGFR and vascular endothelial growth factor A (VEGFA) transcription and with patients overall survival. RESULTS: Association between the presence of E5 transcripts and viral genome disruption was observed for HPV16+ and HPV18+ tumors. Association was not observed between tumors potentially capable of translating E5 and EGFR or VEGFA transcriptional levels. Similarly, the capability of translating E5 and overall survival in patients with HPV16+ squamous cell carcinoma tumors stage ≥ IB2 were not associated. CONCLUSION: The likely presence of E5 transcripts was neither associated to a higher activity of the EGFR-VEGFA pathway nor to the overall survival of patients with HPV16+ squamous cell carcinoma in stages ≥ IB2.


Assuntos
Carcinoma de Células Escamosas/virologia , Proteínas Oncogênicas Virais/genética , Transcrição Gênica , Neoplasias do Colo do Útero/virologia , Adulto , Carcinoma de Células Escamosas/classificação , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Genoma Viral , Humanos , Pessoa de Meia-Idade , Transdução de Sinais , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular/genética
18.
Eur J Cancer Prev ; 29(4): 342-345, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31577564

RESUMO

To understand the impact of demographic, behavioral and contextual factors on cervical cancer, we examined the profile of women classified according to cervical cancer staging [precursor lesions cervical intraephitelial neoplasia (CIN2/CIN3), early- and advanced-stage cancer]. Patients were identified in the main oncological reference hospital in Pará State, Brazil, from 2013 through 2015. Adjusted prevalence ratios and their respective 95% confidence intervals were estimated using Poisson regression with robust variance. The study included 172 cases of CIN2/CIN3 lesions, 158 of early stage and 552 of advanced stage of cervical cancer. The proportion of gynecological complaints as a reason for clinic visit was 2.3 times higher among patients at an early stage compared with patients with CIN2/CIN3 lesions. Compared with early-stage cancer groups, the prevalence of advanced-stage cancer was higher among older patients, those without paid activity (adjusted prevalence ratio = 1.15; confidence interval 95%: 1.03-1.29), those who never had a Pap test (adjusted prevalence ratio = 1.23; confidence interval 95%: 1.08-1.40), those who were seen at the hospital clinic due to gynecological complaints (adjusted prevalence ratio = 1.48; confidence interval 95%: 1.19-1.85) and those who underwent biopsy in the private care system (adjusted prevalence ratio = 1.12; confidence interval 95%: 1.02-1.22). These differences seem to reflect problems in the health system, low socioeconomic level and poor awareness of the importance of Pap tests among those with a diagnosis of advanced-stage cervical cancer.


Assuntos
Detecção Precoce de Câncer/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Brasil/epidemiologia , Colo do Útero/patologia , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Teste de Papanicolaou/psicologia , Teste de Papanicolaou/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Prevalência , Fatores Socioeconômicos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle , Esfregaço Vaginal/psicologia , Esfregaço Vaginal/estatística & dados numéricos , Adulto Jovem , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia
19.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 11): 707-713, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702584

RESUMO

Domain swapping is a widespread oligomerization process that is observed in a large variety of protein families. In the large superfamily of substrate-binding proteins, non-monomeric members have rarely been reported. The arginine-binding protein from Thermotoga maritima (TmArgBP), a protein endowed with a number of unusual properties, presents a domain-swapped structure in its dimeric native state in which the two polypeptide chains mutually exchange their C-terminal helices. It has previously been shown that mutations in the region connecting the last two helices of the TmArgBP structure lead to the formation of a variety of oligomeric states (monomers, dimers, trimers and larger aggregates). With the aim of defining the structural determinants of domain swapping in TmArgBP, the monomeric form of the P235GK mutant has been structurally characterized. Analysis of this arginine-bound structure indicates that it consists of a closed monomer with its C-terminal helix folded against the rest of the protein, as typically observed for substrate-binding proteins. Notably, the two terminal helices are joined by a single nonhelical residue (Gly235). Collectively, the present findings indicate that extending the hinge region and conferring it with more conformational freedom makes the formation of a closed TmArgBP monomer possible. On the other hand, the short connection between the helices may explain the tendency of the protein to also adopt alternative oligomeric states (dimers, trimers and larger aggregates). The data reported here highlight the importance of evolutionary control to avoid the uncontrolled formation of heterogeneous and potentially harmful oligomeric species through domain swapping.


Assuntos
Arginina/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Thermotoga maritima/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Cristalização , Mutação/genética , Ligação Proteica , Homologia Estrutural de Proteína
20.
Arch Gynecol Obstet ; 300(6): 1671-1677, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31616988

RESUMO

PURPOSE: The aim of this study was to investigate the impact of body mass index (BMI) on disease-free survival (DFS) and overall survival (OS) in women diagnosed with EEC and treated at the Brazilian National Cancer Institute. METHODS: The study comprised 849 women diagnosed with EEC who underwent surgical treatment between January, 2000 and December, 2011. The demographic and clinical characteristics of these patients were collected from medical records and their nutritional status was based on the BMI criteria. Univariate (OS and DFS) and multivariate analyses were performed using the Kaplan-Meier method and Cox proportional hazards models, respectively. RESULTS: About 83.2% of patients were obese or overweight at time of diagnosis, with a mean BMI of 31.83. Patients were followed for an average of 34.97 months. There were 111 recurrences (13.1%) and 140 deaths (16.5%), with mean DFS of 51.90 months and mean OS of 52.25 months. There was no significant association between BMI and DFS or OS. In multivariate analysis we did not find an increased hazard of recurrence or death among overweight or obese patients. CONCLUSION: Overweight and obesity had no impact on EEC prognosis on the assessed cohort. Further studies are warranted.


Assuntos
Carcinoma Endometrioide/mortalidade , Neoplasias do Endométrio/mortalidade , Obesidade/complicações , Sobrepeso/complicações , Idoso , Índice de Massa Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
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