Qualitative and quantitative changes in mitochondrial DNA associated with cervical cancer: A comprehensive review.

Cervical cancer is the fourth most commonly diagnosed cancer in women and is considered a preventable disease, as vaccination and screening programs effectively reduce its incidence and mortality rates. Disease physiopathology and malignant cell transformation is a complex process, but it is widely known that high-risk HPV (hrHPV) infection is a necessary risk factor for cancer development. Mitochondria, cell organelles with important bioenergetic and biosynthetic functions, are important for cell energy production, cell growth, and apoptosis. Mitochondrial DNA is a structure that is particularly susceptible to quantitative (mtDNA copy number variation) and qualitative (sequence variations) alterations that are associated with various types of cancer. Novel biomarkers with diagnostic and prognostic value in cervical cancer can be evaluated to provide higher specificity and complement hrHPV molecular testing, which is the most recommended method for primary screening. In accordance with this, this review aimed to assess mitochondrial alterations associated with cervical cancer in clinical cervicovaginal samples, in order to unravel their possible role as specific diagnostic and prognostic biomarkers for cervical malignancy, and also to guide the understanding of their involvement in carcinogenesis, HPV infection, and disease progression.

Variante da Subunidade Beta 3 da Proteína G ( GNB3 ) Está Associada a Alterações Bioquímicas em Pacientes Brasileiros com Hipertensão / G Protein Subunit Beta 3 (GNB3) Variant Is Associated with Biochemical Changes in Brazilian Patients with Hypertension

Resumo Fundamento Genes e suas variantes associadas a fatores ambientais contribuem para o desenvolvimento do fenótipo hipertenso. O gene da subunidade beta 3 da proteína G ( GNB3 ) está envolvido no processo de sinalização intracelular e suas variantes têm sido relacionadas à suscetibilidade à hipertensão arterial. Objetivo Determinar a associação da variante GNB3 (rs5443:C>T) com a hipertensão arterial, parâmetros bioquímicos, idade e obesidade em indivíduos hipertensos e normotensos de Ouro Preto, Minas Gerais. Método A identificação das variantes foi realizada por PCR em tempo real, utilizando o sistema TaqMan®, em amostras de 310 pacientes (155 hipertensos e 155 normotensos). Análises bioquímicas (função renal, perfil lipídico e glicemia) foram realizadas a partir do soro por meio de espectrofotometria UV/Vis e eletrodo íon-seletivo. Foi utilizado um modelo de regressão logística múltipla para identificar fatores associados à hipertensão arterial. A análise das variáveis contínuas com distribuição normal foi realizada usando o teste t de Student não pareado; dados não normais foram analisados usando o teste de Mann-Whitney. Valores de p < 0,05 foram considerados significativos. Resultados A variante rs5443:C>T não esteve associada à hipertensão arterial na população avaliada (p = 0,88). Em relação às medidas bioquímicas, o alelo T esteve associado a níveis elevados de triglicerídeos, glicose e ácido úrico em indivíduos hipertensos (p < 0,05). Conclusão Os presentes resultados mostram a importância do diagnóstico genético para prevenir as causas e consequências de doenças e sugerem que a variante GNB3 rs5443:C>T pode estar associada a alterações no perfil bioquímico em indivíduos hipertensos.

Abstract Background Genes and their variants associated with environmental factors contribute to the development of the hypertensive phenotype. The G protein beta 3 subunit gene (GNB3) is involved in the intracellular signaling process, and its variants have been related to susceptibility to arterial hypertension. Objective To determine the association of the GNB3 variant (rs5443:C>T) with arterial hypertension, biochemical parameters, age, and obesity in hypertensive and normotensive individuals from Ouro Preto, Minas Gerais, Brazil. Method The identification of variants was performed by real-time PCR, using the TaqMan® system, in 310 samples (155 hypertensive and 155 normotensive). Biochemical analyses (renal function, lipid profile and glycemia) were performed from the serum using UV/Vis spectrophotometry and ion-selective electrode. A multiple logistic regression model was used to identify factors associated with arterial hypertension. The analysis of continuous variables with normal distribution was performed using the unpaired Student's t test; non-normal data were analyzed using Mann-Whitney. P < 0.05 was considered significant. Results The rs5443:C>T variant was not associated with arterial hypertension in the evaluated population (p = 0.88). Regarding biochemical measures, the T allele was associated with high levels of triglycerides, glucose and uric acid in hypertensive individuals (p < 0.05). Conclusion These results show the importance of genetic diagnosis to prevent the causes and consequences of diseases and imply that the GNB3 rs5443:C>T variant may be associated with changes in the biochemical profile in hypertensive individuals.

Levels of Folate and Vitamin B12, and Genetic Polymorphisms Involved in One-Carbon Metabolism May Increase the Risk of Cervical Cytological Abnormalities.

To analyze the association of cervical cytological abnormalities with genetic polymorphisms of enzymes involved in folate metabolism, and the effect of micronutrients on association of polymorphisms with cervical carcinogenesis. Our samples were divided in Control (120 women with normal cytology), and Cases: 37 women with Atypical Squamous Cells of Undetermined Significance(ASC-US), 33 participants presenting Low-Grade Squamous Intraepithelial Lesion(LSIL), and 24 women presenting High-Grade cervical lesions(HSIL/ASC-H). We obtained cervical samples for cytological analysis, HPV detection, and analysis of polymorphisms and cervical cell folate. Blood samples were obtained for serum folate and vitamin B12 evaluation. To analyze all polymorphisms simultaneously, we calculated Genetic Risk Score(GRS). Median concentrations were used as cutoff for determination of micronutrient levels. We observed no differences of genotype or allelic frequencies of polymorphisms according to cervical lesions. However, high levels of cervical cell folate and high number of genetic alterations increased risk of High-Grade lesions [OR(IC95%):1.85(0.42-8.11)]. Instead, women with vitamin B12 ≤ 274 pg/ml and GRS ≥ 3 presented even greater risk of HSIL/ASC-H [OR(IC95%):2.91(0.46-18.62)]. High frequency of genetic polymorphisms involved in one-carbon metabolism associated with high levels of cell folate or low levels of serum vitamin B12, increased the risk of High-Grade lesion in uterine cervix.

Bacterial vaginosis: prevalence, risk profile and association with sexually transmitted infections / Vaginose bacteriana: prevalência, perfil de risco e associação com infecções sexualmente transmissíveis / Vaginosis bacteriana: prevalencia, perfil de riesgo y asociación con infecciones de transmisión sexual

Background and Objectives: Bacterial vaginosis (BV) is the most common cause of vaginal discharge in the world. The study aimed to estimate the prevalence and to identify risk factors associated with bacterial vaginosis. Methods: A cross-sectional study was conducted in Ouro Preto, Brazil, between February and December 2017. Three hundred and forty-one women aged 18 years or older, users of the Brazilian Unified Health System, participated in this study. Women who used oral or topical antibiotics in the four weeks prior to the sample collection and women who had undergone a total hysterectomy were excluded from the study. After signing the Informed Consent Form and filling out a questionnaire containing sociodemographic, behavioral and sexual data, the participants were directed to the collection room, where the nurse collected the samples for the preventive examination of the cervix and also two vaginal swabs. Vaginal swabs and cervical samples were analyzed for cytological abnormalities and BV using Gram staining and cytology. Pathogens causing sexually transmitted infections (STIs) were identified by Polymerase Chain Reaction (PCR). For the analysis of the data, statistical package STATA version 10.0 was used. This study was approved by the Research Ethics Committee of the Federal University of Ouro Preto (UFOP). Results: During the study, 341 women were evaluated. The prevalence of BV using Gram staining (32.5% [CI95% 27.7-37.7%]) and cytology (27.7% [CI95% 23.032.8%]) was similar, however, the sensitivity of cytology was lower (77.8%). Risk factors associated with BV were smoking (IRR 1.5 [CI95%: 1.1  2.1]), use of an intrauterine device (IRR 2.8 [CI95%: 1.2 - 6.5]), and past medical history of BV (IRR 1.5 [CI95%: 1.1 - 2.1]). Correlation between the presence of BV and Trichomonas vaginalis (TV) infection (r=0.24) was observed. Conclusion: The prevalence of BV was affected by life habits and was prevalent in women with TV. Thus, behavioral and social prevention approaches to women with diverse risk profiles may help mitigate TV/BV prevalence and recurrence of BV.(AU)

Contexte et objectifs: La vaginose bactérienne (VB) est la cause la plus fréquente de pertes vaginales dans le monde. Le but de cette étude était d'évaluer la prévalence et les facteurs associés à la vaginose bactérienne. Méthodes: Il s'agit d'une approche descriptive, transversale et quantitative réalisée à Ouro Preto, Minas Gerais, Brésil, entre février et décembre 2017. 341 femmes ont participé à cette étude, âgées de 18 ans ou plus, utilisatrices du Système de santé unifié. Les femmes ayant utilisé des antibiotiques oraux ou topiques dans les quatre semaines précédant le prélèvement et les femmes ayant subi une hystérectomie totale ont été exclues de l'étude. Après avoir signé le formulaire de consentement éclairé et rempli un questionnaire contenant des données sociodémographiques, comportementales et sexuelles, les participants ont été dirigés vers la salle de collecte, où l'infirmière a prélevé les échantillons pour l'examen préventif du col de l'utérus. et aussi deux écouvillons vaginaux. Les échantillons de frottis vaginaux et cervicaux ont été analysés pour les anomalies cytologiques et VB en utilisant la coloration de Gram et la cytologie. Les agents pathogènes causant des infections sexuellement transmissibles (IST) ont été identifiés par réaction en chaîne par polymérase. Pour l'analyse des données, le progiciel statistique STATA version 10.0 a été utilisé. Cette étude a été approuvée par le Comité d'éthique de la recherche de l'Université fédérale d'Ouro Preto (UFOP). Résultats: Au cours de l'étude, 341 femmes ont été évaluées. La prévalence de la VB avec coloration de Gram (32,5% [IC 95% 27,7 - 37,7%]) et de la cytologie (27,7% [IC 95% 23,0 - 32,8%]) était similaire, cependant la sensibilité cytologique était plus faible (77,8%). Les facteurs de risque associés à la VB étaient le tabagisme (IRR 1,5 [IC 95%: 1,1 - 2,1]), l'utilisation d'un dispositif intra-utérin (IRR 2,8 [IC 95%: 1,2 - 6,5] ) et antécédents médicaux de VB (IRR 1,5 [IC 95%: 1,1 - 2,1]). Il y avait une corrélation entre la présence d'une infection à VB et Trichomonas vaginalis (TV) (r = 0,24). Conclusion: La prévalence de la VB était affectée par le mode de vie et l'infection TV. Ainsi, les approches de prévention comportementale et sociale pour les femmes présentant des profils de risque différents peuvent aider à atténuer la prévalence de la TV / VB et la récurrence de la VB.(AU)

Justificativa e Objetivos: A vaginose bacteriana (VB) é a causa mais comum de corrimento vaginal no mundo. O objetivo desse estudo foi avaliar a prevalência e os fatores associados à vaginose bacteriana. Métodos: Trata-se de um descritivo, de forma transversal e abordagem quantitativa realizado em Ouro Preto, Minas Gerais, Brasil, entre fevereiro a dezembro de 2017. Participaram desse estudo 341 mulheres com idade igual ou superior a 18 anos, usuárias do Sistema Único de Saúde (SUS). Mulheres que usaram antibióticos orais ou tópicos nas quatro semanas anteriores à coleta e mulheres que haviam sido submetidas a uma histerectomia total foram excluídas do estudo. Após a assinatura do Termo de Consentimento Livre e Esclarecido e preenchimento de questionário contendo dados sócio-demográfico, comportamental e sexual, as participantes foram encaminhadas para a sala de coleta, onde a enfermeira realizou a coleta das amostras para o exame preventivo do colo do útero e também de dois swabs vaginais. As amostras de esfregaço vaginal e cervical foram analisadas quanto às anormalidades citológicas e VB usando coloração de Gram e citologia. Patógenos causadores de infecções sexualmente transmissíveis (ISTs) foram identificados por Reação em Cadeia da Polimerase (PCR). Para a análise dos dados foi utilizado o pacote estatístico STATA versão 10.0. O presente estudo foi aprovado pelo Comitê de Ética em Pesquisa da Universidade Federal de Ouro Preto (UFOP). Resultados: Durante o estudo, 341 mulheres foram avaliadas. A prevalência de VB com coloração de Gram (32,5% [IC95% 27,7 - 37,7%]) e citologia (27,7% [IC95% 23,0 - 32,8%]) foi semelhante, porém a sensibilidade da citologia foi menor (77,8%). Os fatores de risco associados ao VB foram tabagismo (IRR 1,5 [IC95%: 1,1 - 2,1]), uso de dispositivo intrauterino (IRR 2,8 [IC 95%: 1,2 - 6,5]) e história médica pregressa de VB (IRR 1,5 [IC95%: 1,1 - 2.1]). Observou-se correlação entre a presença de infecção por VB e Trichomonas vaginalis (TV) (r = 0,24). Conclusão: A prevalência de VB foi afetada por hábitos de vida e infecção por TV. Assim, abordagens de prevenção comportamental e social para mulheres com diversos perfis de risco podem ajudar a mitigar a prevalência de TV / VB e recorrência de VB.(AU)

Association of serum folate and vitamin B12 with pre-neoplastic cervical lesions.

BACKGROUND & AIMS: Diet and lifestyle play an important role in etiology of various tumors. Serum concentration of folate and vitamin B12may be associated with carcinogenesis since they are involved in DNA methylation and nucleotide synthesis. However, the role of these micronutrients on development of cervical cancer is still controversial. Thus, the aim of this study was to analyze the association of lower status of folate and vitamin B12 with the risk of pre-neoplastic cervical lesions. METHODS: Our sample group was divided in Control group (n = 120) - women with normal cytology, and Case groups (n = 57) - women presenting Atypical Squamous Cells of Undetermined Significance (ASC-US, n = 21), Low Grade Squamous Intraepithelial Lesion (LSIL; n = 16), and High-Grade lesions (n = 20). We obtained cervical samples for cytology analysis and HPV detection, and blood samples for evaluation of serum concentration of folate and vitamin B12. RESULTS: No difference of serum folate was observed among Cases and Control groups. On the other hand, women with High-Grade lesions presented significant lower median concentration of vitamin B12 if compared to another groups. Then, we observed increased risk of High-Grade lesions among participants with low vitamin B12 levels was observed in relation to women that presented high levels of the micronutrient and from Control group [OR (95% CI): 2.09 (0.65-6.76), p = 0.216], ASC-US [OR (95% CI): 3.15 (0.82-12.08), p = 0.095], and LSIL [OR (95% CI): 3.10 (0.76-12.70), p = 0.116]. CONCLUSIONS: Low concentration of vitamin B12 was associated with an increased risk of High-Grade cervical lesions. Besides, we did not observe any difference of serum folate among women with normal cytology and women with pre-neoplastic cervical lesions.

3'UTR polymorphism of Thymidylate Synthase gene increased the risk of persistence of pre-neoplastic cervical lesions.

BACKGROUND: Cervical cancer is caused by high-risk Human Papillomavirus (hr-HPV) infection associated with cofactors that has been analyzed as predictors of the remission or persistence of cytological abnormalities remission or persistence. These cofactors can be either environmental, epigenetic, or genetic. Polymorphism in genes of enzymes that act on one-carbon metabolism alter their activity and also may be associated with cervical carcinogenesis because they affect DNA synthesis and repair, and gene expression. Therefore, this study aimed to analyze the risk of persistence of pre-neoplastic cervical lesions according to genetic polymorphisms involved in one-carbon metabolism. METHODS: Our sample consisted of 106 women, divided into two groups - Remission (n = 60), i.e., with the presence of pre-neoplastic lesions at first meeting (T1) and normal cytology after 6 months of follow-up (T2), and Persistence (n = 46), i.e., with the presence of pre-neoplastic lesions at T1 and T2. We obtained cervical samples for cytological analysis (T1 and T2), HPV detection (T1), and evaluation of polymorphism C667T of Methylenetetrahydrofolate Reductase (MTHFR C677T), A2756G of Methionine Synthase (MS A2756G), A66G of Methionine Synthase Reductase (MTRR A66G), double or triple 28 bp tandem repeat in 5'-untranslated enhanced region of Thymidylate Synthase (TSER), and 6 bp deletion at nucleotide 1494 in TS 3'-untranslated region (TS3'UTR). To analyze all genetic polymorphisms simultaneously, we calculated the Genetic Risk Score (GRS). RESULTS: We observed no differences between the Remission and Persistence groups regarding the GRS. Also, there were no differences in the genotypic and allelic distribution of MTHFR C677T and MS A2756G polymorphisms. However, the risk of persistence was higher among women with the heterozygote genotype - ins/del [OR (IC95%): 3.22 (1.19-8.69), p = 0.021], or the polymorphic genotype - del/del [OR (IC95%): 6.50 (1.71-24.70), p = 0.006] of TS3'UTR. CONCLUSIONS: The presence of the TS3'UTR polymorphism increased the risk of persistence of cervical abnormalities. This genetic variant could be a potential marker of cervical carcinogenesis and therefore assist the follow-up of women with persistent pre-neoplastic cervical lesions.

Knowledge about cervical cancer and HPV immunization dropout rate among Brazilian adolescent girls and their guardians.

BACKGROUND: Infections with Human Papillomavirus (HPV) are the main cause of cervical cancer. Since 2014, the HPV vaccine was introduced in the Brazilian National Vaccination Calendar. The purpose of this study was to assess the knowledge of adolescent girls and their mothers/guardians about HPV and HPV vaccine, identify the factors associated with this knowledge, and evaluate immunization dropout rate. METHODS: This was a cross-sectional study involving adolescent girls and their mothers/guardians. Participants underwent an interview that addressed sociodemographic data, sexual and gynecological history, and knowledge about HPV, HPV vaccine and cervical cancer. The third quartile of the total score was established as a cutoff for assessing knowledge. Adolescents who correctly answered more than four questions and mothers/guardians who obtained more than five correct responses were categorized into high knowledge. Poisson regression analysis was performed to identify variables associated with low knowledge. Vaccination records were used to assess immunization dropout rates. Any adolescent who did not complete the two-dose vaccination schedule was considered dropout. RESULTS: A total of 666 adolescent girls and 623 mothers/guardians were interviewed. Low knowledge was observed in 76.7% of adolescents and 79.8% of mothers/guardians. Most were unaware of the causal relationship between HPV and cervical cancer, signs and symptoms of HPV infection, and had limited knowledge about the HPV vaccine. Factors associated with low knowledge of adolescents were aged 12 years [IRR 1.2 (95% CI 1. 1-1.3)] or less [IRR 1.3 (95% CI (1. 2-1.4)]; household income lower than US$750 [IRR 1.7 (95% CI 1. 1-2.6)] and household income between US$751 and US$1500 [IRR 1.6 (95% CI 1.0-2.6)]. Among mothers/guardians, low knowledge was related to having completed elementary school or less [IRR 1.5 (95% CI 1. 2-2.0)]; and household income lower than US$750 [IRR 1.2 (95% CI 1.0-1.4)]. Knowledge of adolescents and mothers/guardians was not associated with vaccine uptake. HPV immunization dropout rate was considered high (32.3%). CONCLUSION: Knowledge about HPV and cervical cancer as well as vaccine uptake was low. Results highlight the need for educational interventions about HPV and cervical cancer. These actions may contribute to improve adherence to HPV vaccination.

Lack of association between methylenetetrahydrofolate reductase C677T polymorphism, HPV infection and cervical intraepithelial neoplasia in Brazilian women.

BACKGROUND: Cervical cancer has high prevalence and mortality rates in worldwide female population. Persistent infection by high-risk Human Papillomavirus (hr-HPV) is the main cause of this cancer. However, many environmental, genetical, and epigenetical cofactors can modulate viral infection and cervical carcinogenesis. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is a genetic factor that has been associated with many pathologies, including cancer. Nevertheless, studies with cervical cancer presented controversial results, and varied according to ethnicity. Thus, the aim of this study was to determine association between MTHFR C677T polymorphism, Human Papillomavirus (HPV) infection and cervical cancer. METHODS: A case-control study was performed with 150 histological cervical samples. Case group were divided in Cervical Intraepithelial Neoplasia (CIN) grade I (n = 30), CIN II (n = 30), CIN III (n = 30), and Squamous Cervical Carcinoma (SCC) (n = 30). Control group was composed by 30 samples without lesion, presenting cervicitis. HPV detection was performed by conventional Polymerase Chain Reaction (PCR) with SPF primers set, and by real-time PCR specific for HPV 16 and hr-HPV. MTHFR C677T polymorphism was analyzed by PCR followed by Restriction Fragment Length Polymorphism (RFLP). RESULTS: Frequency of MTHFR CC genotype was 72.7% (n = 109), CT 23.3% (n = 35) and TT 4.0% (n = 6). Polymorphic T allele frequency was 15.7%. No statistically significant association was observed between MTHFR C677T polymorphism and presence of pre-neoplastic or neoplastic cervical lesions. Similar frequencies of T allele was observed in control (23.3%) and cases (13.3%) groups (p = 0.174). In addition, there was no statistically significant association between MTHFR C677T polymorphism and viral infection, even considering hr-HPV or HPV 16 positivity. CONCLUSION: MTHFR C677T polymorphism was not associated with cervical cancer and HPV infection.

Comparison of Capillary Electrophoresis, AGE, and PAGE for MTHFR Polymorphism Analysis in FFPE Cervical Samples.

BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism analysis could help in diagnosis, treatment, and prognosis of some pathologies, since it has been associated with the development of cardiovascular diseases, defects in neural tube formation, psychiatric disorders, and cancer. Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) is the most commonly used technique to analyze this polymorphism. Usually, RFLP products are evaluated by agarose gel electrophoresis (AGE) or polyacrylamide gel electrophoresis (PAGE). However, capillary electrophoresis (CE) may represent an alternative for MTHFR C677T polymorphism analysis by PCR-RFLP. Thus, the aim of this study was to compare CE, AGE, and PAGE to MTHFR C677T polymorphism analysis of Formalin-Fixed and Paraffin-Embedded (FFPE) cervical samples. METHODS: 150 biopsy blocks of cervical samples were analyzed. MTHFR polymorphism was evaluated by PCR-RFLP, and the products generated were analyzed by CE, AGE, and PAGE. Concordance between the methods was evaluated by rate agreement, Kappa coefficient, and McNemars's Test. RESULTS: Eight samples (5.4%) showed discordant results according to CE and PAGE or AGE. Differences of CC and CT frequencies were observed between CE and AGE (p=0.016): CC genotype varied from 68.0% to 72.7%, and CT varied from 23.3% to 27.3%. Besides, Kappa coefficient between CE and AGE, or PAGE was very high (κ>0.81). CONCLUSION: Capillary electrophoresis presented high agreement with PAGE and AGE, and may be an accurate, safe, and quick alternative method for MTHFR polymorphism analysis.

Morphometric evaluation and nonclassical criteria for the diagnosis of HPV infection and cytological atypia in cervical samples.

Herein, we evaluated cervical samples from normal tissue or HPV-infected tissue, to determine if the relative nuclear/cytoplasmic ratio (NA/CA) and the presence of nonclassical cytological criteria are a novel cytological criterion for the diagnosis of HPV. Significantly, larger NA/CA ratios were found for the HPV-ATYPIA+ and HPV+ATYPIA+ groups compared with HPV-ATYPIA- group, regardless of collection method. For the samples collected with a spatula, only three samples from the HPV-ATIPIA- group showed four or more nonclassical parameters (i.e., were positive), while a larger number of the samples in the HPV-ATYPIA+, HPV+ATYPIA-, and HPV+ATYPIA+ groups were positive (13, 4, and 13 samples, respectively). Among those collected with a brush, no sample showed four or more nonclassical criteria in the HPV-ATYPIA- group, while a number of samples were positive in the HPV-ATYPIA+, HPV+ATYPIA-, and HPV+ATYPIA+ groups (4, 3, and 4 samples, respectively). HPV infection was associated with significant morphometrical changes; no increase in the NA/CA ratio was found in the HPV+ATYPIA- samples, compared with the HPV-ATIPIA- samples collected with either a spatula or a brush. In conclusion, by including nonclassical cytological criteria into the patient diagnosis, we were able to reduce the number of false negative and false positive HPV diagnoses made using conventional cytology alone.