RESUMEN
Circulating DNA can be released in the biological fluids by a physiological process and by different pathological conditions. The first reports detecting circulating DNA in human plasma date from the late 40s. Even when specific pathological conditions were analyzed, the clinical importance of circulating DNA remained unclear. After PCR introduction, genetic and epigenetic alterations in circulating DNA gained more prominence for understanding the mechanisms of cancer development and progression. Nowadays, the circulating DNA assays are highlighted for their clinical relevance for cancer screening in liquid biopsy. In this review, we described the landscape of studies on circulating DNA isolated from human plasma or serum and the molecular tools used to obtain these findings throughout the 20th century and the current application in cancer.
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Ácidos Nucleicos Libres de Células , Neoplasias , Biomarcadores de Tumor/genética , Detección Precoz del Cáncer , Humanos , Biopsia Líquida , Neoplasias/diagnóstico , Neoplasias/genéticaRESUMEN
Breast impalpable lesions have become a clinical dilemma because they are small, presenting a heterogeneous cellular phenotype. The aim of this study was to evaluate the mutational profile of the PIK3CA, TP53, and CDKN2A genes, comparing the mammary tissue with the respective circulating free DNA (cfDNA). The PIK3CA, TP53, and CDKN2A genes were sequenced (PCR-Sanger) in 58 women with impalpable lesions (49 malignant and 9 benign) with the respective cfDNA. The chi-square or Fisher's exact test was used to evaluate statistical significance between the clinical variables and mutational profile. A total of 51 out of 58 samples generated successful mutation profiles in both breast lesion and cfDNA. Of the 37 mutations detected, 10 (27%) and 16 (43%) mutations were detected in benign and malignant breast lesions, respectively, while 2 (5%) and 9 (24%) were found in cfDNA of women with benign and malignant lesions, respectively. The lymph node involvement with mutations in the PIK3CA in malignant lesions (Pâ¯=â¯0.001), and the relationship between mutations in PIK3CA, comparing ductal tumors with benign lesions (Pâ¯=â¯0.05), were statistically significant. This study detected different mutations in PIK3CA, TP53, and CDKN2A genes, which represent, in part, the heterogeneity of impalpable lesions. The results confirm that more studies should be conducted on the functional role of cfDNA in the impalpable lesions.
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Neoplasias de la Mama/genética , Mama/química , Ácidos Nucleicos Libres de Células/genética , Metástasis Linfática/genética , Mutación , Análisis de Secuencia de ADN/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Mama/patología , Neoplasias de la Mama/patología , Fosfatidilinositol 3-Quinasa Clase I/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Detección Precoz del Cáncer , Femenino , Heterogeneidad Genética , Humanos , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/genéticaRESUMEN
The aim of this study was to identify genes with higher expression in solid tumor cells by comparing human tumor biopsies with healthy blood samples using both in silico statistical analysis and experimental validations. This approach resulted in a novel panel of 80 RNA biomarkers with high discrimination power to detect circulating tumor cells in blood samples. To identify the 80 RNA biomarkers, Affymetrix HG-U133 plus 2.0 microarrays datasets were used to compare breast tumor tissue biopsies and breast cancer cell lines with blood samples from patients with conditions other than cancer. A total of 859 samples were analyzed at the discovery stage, consisting of 417 mammary tumors, 41 breast lines, and 401 control samples. To confirm this discovery, external datasets of eight types of tumors were used, and experimental validation studies (NanoString n-counter gene expression assay) were performed, totaling 5028 samples analyzed. In these analyses, the 80 biomarkers showed higher expression in all solid tumors analyzed relative to healthy blood samples. Experimental validation studies using NanoString assay confirmed the results were not dependent of the gene expression platform. A panel of 80 RNA biomarkers was described here, with the potential to detect solid tumor cells present in the blood of multiple tumor types.
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Biomarcadores de Tumor , Neoplasias/genética , Transcriptoma , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Células Neoplásicas Circulantes/metabolismo , Reproducibilidad de los ResultadosRESUMEN
HER2-enriched tumors are responsible for 20% of breast tumors and have high rates of immune infiltrates in the tumor stroma that respond favorably to neoadjuvant chemotherapy. In the context of tumors, telomeres control cell death and prevent tumor cells from replicating discontinuously, leading to their immortalization. This study aimed to evaluate the presence of tumor-infiltrating lymphocytes, hTERT expression, hTERT promoter mutation, and leukocyte telomere length in HER2-enriched breast tumors. A total of 103 cases were evaluated, 19 with pathologic complete response. The TILs percentage was above ≥10 in 44 cases (43%) and significantly present in patients ≥50 years of age. hTERT staining positivity was mostly nuclear, significantly present in the non-pCR group, and associated with a lower survival rate. Leukocyte telomeres were elongated for HER2-enriched tumors, and in multivariate analysis, shortening was associated with an increased risk of death. Overall, our results show that the nuclear and cytoplasmic presence of hTERT may indicate a worse prognosis and that leukocyte telomere elongation is a protective factor.
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Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Terapia Neoadyuvante/métodos , Pronóstico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismoRESUMEN
Head and neck squamous cell carcinomas (HNSCCs) represent the most common epithelial tumors that arise from mucosa of the oral cavity, pharynx, and larynx. The development of HNSCCs is usually associated with tobacco use, alcohol consumption, and human papillomavirus (HPV) infection. Most HNSCCs are diagnosed in advanced states, leading to a worse clinical outcome. Screening tests based on potential biomarkers associated with HNSCCs could improve this scenario. Liquid biopsy has emerged as a promising area of cancer investigation, offering a minimally invasive approach to track circulating biomarkers in body fluids that could potentially contribute to the diagnosis, predict prognosis, and monitor response to treatment. This review will discuss translational studies describing the clinical applications of liquid biopsy in HPV-negative and HPV-positive HNSCCs focused on circulating nucleic acids [cell-free DNA (cfDNA) and cell-free RNA (cfRNA)], circulating tumor cells (CTCs), and extracellular vesicles (EVs), which can be found in plasma, serum, and saliva.
RESUMEN
Liquid biopsy represents a procedure for minimally invasive analysis of non-solid tissue, blood and other body fluids. It comprises a set of analytes that includes circulating tumor cells (CTCs) and circulating free DNA (cfDNA), RNA, long noncoding RNA (lncRNA) and micro RNA (miRNA), as well as extracellular vesicles. These novel analytes represent an alternative tool to complement diagnosis and monitor and predict response to treatment of the tumoral process and may be used for other disease processes such viral and parasitic infection. This review focuses on the biologic and molecular characteristics of cfDNA in general and the molecular changes (mutational and epigenetic) proven useful in oncologic practice for diagnosis, monitoring and treatment of breast cancer specifically.
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Neoplasias de la Mama/genética , Carcinogénesis/genética , Ácidos Nucleicos Libres de Células/genética , Animales , Neoplasias de la Mama/metabolismo , Ácidos Nucleicos Libres de Células/metabolismo , Femenino , HumanosRESUMEN
BACKGROUND AND OBJECTIVE: Gas station attendants are occupationally exposed to benzene, toluene, ethylbenzene and xylene (BTEX) compounds and thus more susceptible to the biological effects of this mixture present in gasoline, especially due to the carcinogenicity of benzene. Furthermore, the harmful effects of BTEX exposure may be potentiated by genetic and epigenetic inactivation of critical genes. The objective was to evaluate such gene-BTEX interactions accessing the promoter methylation status of p14ARF, p16INK4A and GSTP1 in peripheral blood leukocyte samples. MATERIALS AND METHODS: The 59 exposed and 68 unexposed participants from Rio de Janeiro, Brazil, were included. The promoter methylation status was accessed by methylation-specific PCR (MSP) and GSTP1 Ile105Val polymorphism was investigated by PCR-restriction fragment length polymorphism (PCR-RFLP) technique. RESULTS: Both p14ARF and p16INK4A were significantly hypermethylated in exposed subjects compared to unexposed (p = 0.004 and p<0.001, respectively). Additionally, p16INK4A hypermethylation in the exposed group was correlated with chromosomal abnormalities (CAs) (p = 0.018), thus highlighting the influence of the gene-environment interactions on genome instability. Noteworthy, p16INK4A methylation was significantly associated with miscarriage among female attendants (p = 0.047), in which those who reported miscarriage exhibited hypermethylation in at least 2 of the 3 genes analyzed. The GSTP1 heterozygote genotype, which could affect the metabolism of benzene detoxification, was found in both groups but was more frequent in those occupationally exposed. No significant association was observed between GSTP1 genotypes and methylation status. CONCLUSION: Together, these findings indicate that gas station attendants with the aforementioned epigenetic and genetic profiles may be at greater risk of occupational BTEX exposure-induced genome instability, which could require concerted efforts to establish more preventive actions and constant biomonitoring in gas station attendants.
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Derivados del Benceno/efectos adversos , Metilación de ADN/efectos de los fármacos , Gasolina/efectos adversos , Regiones Promotoras Genéticas/efectos de los fármacos , Tolueno/efectos adversos , Xilenos/efectos adversos , Adulto , Brasil , Estudios de Casos y Controles , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Femenino , Inestabilidad Genómica , Gutatión-S-Transferasa pi/genética , Humanos , Exposición por Inhalación/efectos adversos , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Salud Laboral , Polimorfismo Genético , Medición de Riesgo , Proteína p14ARF Supresora de Tumor/genéticaRESUMEN
The objective of the present study was to evaluate the epigenetic changes occurring in early stages of breast cancer. The present study investigated the methylation profile of the ATM, p14ARF and p16INK4a promoters in total blood and plasma cell-free DNA (cfDNA) from women with impalpable breast lesions compared with in total blood of a control cohort of women without breast lesions. The samples were evaluated using the methylation-specific PCR method. The Fisher's exact test was used to evaluate statistical significance between the methylation and clinical variables. A total of 111 women were evaluated, including 56 women with impalpable breast cancer (39/56 also had paired plasma cfDNA) and 55 women in the control cohort (55 blood DNA). For blood DNA from women with malignant impalpable breast lesions, p16INK4a exhibited the greatest percentage of methylation (48%), followed by ATM (37.5%) and p14ARF (27%) promoters, regardless of age variation. For plasma cfDNA, the methylation rates for ATM, p14ARF and p16INK4a were 26, 26 and 10%, respectively. The methylation rates for the blood DNA of controls were the lowest for ATM (9%), p14ARF (7%) and p16INK4a (7%). The women with impalpable breast lesions (benign and malignant lesions) exhibited the highest methylation rate, regardless of age, compared with the paired plasma cfDNA and controls. This epigenetic change was statistically significant for the promoters of ATM (P=0.009) and p16INK4a (P=0.001) (impalpable breast lesions vs. control). The present study demonstrated that epigenetic changes occurring in the ATM and CDKN2A genes detectable in liquid biopsy were associated with the development of impalpable breast lesions.
RESUMEN
BACKGROUND: With the development of new drug combinations and targeted treatments for multiple types of cancer, the ability to stratify categories of patient populations and to develop companion diagnostics has become increasingly important. A panel of 325 RNA biomarkers was selected based on cancer-related biological processes of healthy cells and gene expression changes over time during nonmalignant epithelial cell organization. This "cancer in reverse" approach resulted in a panel of biomarkers relevant for at least 7 cancer types, providing gene expression profiles representing key cellular signaling pathways beyond mutations in "driver genes." Objective. To further investigate this biomarker panel, the objective of the current study is to (1) validate the assay reproducibility for the 325 RNA biomarkers and (2) compare gene expression profiles side by side using two technology platforms. METHODS AND RESULTS: We have mapped the 325 RNA transcripts and in a custom NanoString nCounter expression panel to be compared to all potential probe sets in the Affymetrix Human Genome U133 Plus 2.0. The experiments were conducted with 10 unique biological formalin-fixed paraffin-embedded (FFPE) breast tumor samples. Each site extracted RNA from four sections of 10-micron thick FFPE tissue over three different days by two different operators using an optimized standard operating procedure and quality control criteria. Samples were analyzed using mas5 in BioConductor and NanoStringNorm in R. Pearson correlation showed reproducibility between sites for all 60 samples with r = 0.995 for Affymetrix and r = 0.999 for NanoString. Correlation in multiple days and multiple users was for Affymetrix r = (0.962 - 0.999) and for NanoString r = (0.982 - 0.991). CONCLUSION: The 325 RNA biomarkers showed reproducibility in two technology platforms with moderate to high concordance. Future directions include performing clinical validation studies and generating rationale for patient selection in clinical trials using the technically validated assay.
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Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , ARN/genética , Biomarcadores de Tumor/normas , Neoplasias de la Mama/patología , Femenino , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/normas , ARN/normas , Reproducibilidad de los ResultadosRESUMEN
OBJECTIVE: The aim of this study was to investigate the presence of human papillomavirus (HPV) in biopsy specimens from juvenile and adult patients with histopathological diagnosis of recurrent respiratory papillomatosis (RRP) treated in two public hospitals in Rio de Janeiro, Brazil. METHODS: We performed the detection and genotyping of HPV by PCR technique for the types 6, 11, 16, and 18 in biopsy specimens from 41 RRP patients. RESULTS: The juvenile onset RRP (JoRRP) corresponded to 61% and the adult onset RRP (AoRRP) corresponded to 39% of the study group. Prevalence of males was observed in both the adult (81.3%) and the juvenile (56%) groups. Lesions in the larynx were more frequent in the glottis (46%). Genotyping analysis only revealed patients with HPV-6 (34.1%), HPV-11(17.1%), and co-infection HPV-6 and -11 (48.8%). RRP severity was significantly associated with the JoRRP (p<0.001), with extralaryngeal disease and more surgeries. However, no significant association between RRP severity and HPV types was found. One co-infected patient in the JoRRP died due to the evolution of the disease with lung involvement. CONCLUSION: These results show the strong association of HPV-6 and/or HPV-11 types with RRP and could complement the diagnosis, prognosis, and therapies for these patients. In addition, the HPV vaccination should be encouraged to prevent the disease.
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Enfermedades de la Laringe/epidemiología , Enfermedades Pulmonares/epidemiología , Infecciones por Papillomavirus/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Enfermedades de la Tráquea/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Femenino , Genotipo , Papillomavirus Humano 11/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Papillomavirus Humano 6/genética , Humanos , Enfermedades de la Laringe/virología , Enfermedades Pulmonares/virología , Masculino , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Prevalencia , Infecciones del Sistema Respiratorio/virología , Estudios Retrospectivos , Riesgo , Enfermedades de la Tráquea/virologíaRESUMEN
Background: Low levels of vitamin D have been described as a risk factor for the development of breast cancer. The aim of this study was to evaluate the serum levels of vitamin D (25OHD) in patients with impalpable breast lesions comparing with a control group. Methods: Vitamin D quantification (25OHD) was assessed in the plasma of 65 patients with impalpable breast lesions and from 20 health controls using a chemiluminescent microparticle immunoassay. Pearson's chi-square test and nonparametric t-Student were used to evaluate statistical significance between the clinical variables and the means of quantification of vitamin D. The receiver operating characteristic (ROC) curve was used to evaluate the correlation between age and vitamin sufficiency for the cases and the controls. Results: The prevalence of vitamin D deficiency and/or insufficiency in women with malignant lesions was 84% and 60% for the control group. Using the chi-square or Fisher's exact test, the relationship between vitamin D levels and age presented significant association only for the control group (P=0.002). Using ROC curve, the plot area (0.778) for the control group defined a cut-off value of 45 years to age, with specificity and sensitivity of 60% and 50%, respectively. Thus, the odds ratio for vitamin D insufficiency in women over 45 years was 1.37 (P=0.011). For the case group, clinical characteristics, histological grade, and lymph node involvement did not show any significant association. Conclusion: The prevalence of vitamin D deficiency/insufficiency is high in women with impalpable breast lesions, as well as in the control group, even in a tropical city. According to the results the age advancement may be involved with the decrease in vitamin D levels in plasma, but there was no statistical association between low levels of Vitamin D and breast cancer.
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Neoplasias de la Mama/complicaciones , Carcinoma Ductal de Mama/complicaciones , Carcinoma Intraductal no Infiltrante/complicaciones , Carcinoma Lobular/complicaciones , Deficiencia de Vitamina D/epidemiología , Vitamina D/sangre , Vitaminas/sangre , Adulto , Brasil/epidemiología , Neoplasias de la Mama/sangre , Carcinoma Ductal de Mama/sangre , Carcinoma Intraductal no Infiltrante/sangre , Carcinoma Lobular/sangre , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Prevalencia , Pronóstico , Factores de Riesgo , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/etiologíaRESUMEN
Gas station workers are exposed to chemicals known to be carcinogenic, especially benzene. The objective was to analyze the health problems of female gas station workers by means of sociodemographic and clinical questionnaires, and laboratorial exams. We performed the genotyping of the polymorphisms BRCA1/P871L and BRCA1/Q356R by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism, and of variant allele BRCA2/N372H through direct sequencing. The female workers showed a higher concentration of monocytes (P = 0.039); a greater number of spontaneous abortions (P = 0.025, OR = 4.977, 95% CI = 1.135-30.669); higher tobacco consumption (P = 0.013); and higher alcohol consumption (P = 0.05). The statistical analysis of the polymorphisms associated with the variables monocyte concentration and miscarriage number did not reveal a significant relationship, and smoking and spontaneous abortion were not statistically associated either. Environ. Mol. Mutagen. 58:730-734, 2017. © 2017 Wiley Periodicals, Inc.
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Alcanos/toxicidad , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Adulto , Consumo de Bebidas Alcohólicas/efectos adversos , Brasil , Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/patología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Exposición Profesional , Polimorfismo de Nucleótido Simple , Uso de Tabaco/efectos adversosRESUMEN
Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal bone marrow disorders characterized by ineffective hematopoiesis, different degrees of cellular dysplasia, and increased risk of progression to acute myeloid leukemia. International Prognostic Scoring System is the gold standard for MDS classification; however, patients exhibiting different clinical behaviors often coexist in the same group, indicating that the currently available scoring systems are insufficient. The genes that have recently been identified as mutated in MDS, including additional sex combs like 1, transcriptional regulator (ASXL1), tumor protein p53 (TP53), and KRAS proto-oncogene and GTPase (KRAS)/NRAS proto-oncogene, GTPase (NRAS), may contribute to a more comprehensive classification, as well as to the prognosis and progression of the disease. In the present study, the mutations in the ASXL1, TP53 and NRAS/KRAS genes in 50 patients were evaluated by sequencing genomic bone marrow DNA. Nine patients (18%) presented with at least one type of mutation. Mutations in TP53 were the most frequent in six patients (12%), followed by ASXL1 in two patients (4%) and NRAS in one patient (2%). The nine mutations were detected in patients with low- and high-risk MDS. The screening of mutations in MDS cases contributes to the application of personalized medicine.
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The present study evaluated the proteomic profile of saliva and plasma from women with impalpable breast lesions using nano-liquid chromatography-quadrupole-time-of-flight (nLC-Q-TOF) technology. Plasma and saliva from patients with fibroadenoma (n=10), infiltrating ductal carcinoma (n=10) and healthy control groups (n=8) were assessed by combinations of inter/intra-group analyses, revealing significant quantitative and qualitative differences. The major differentially-expressed proteins in the saliva of patients compared with the controls were α2-macroglobulin and ceruloplasmin, but the proteins that met the minimum fold-change and P-value cut-offs were leukocyte elastase inhibitor and α-enolase, and deleted in malignant brain tumors 1. Concerning plasma, α-2-macroglobulin and ceruplasmin were upregulated, while other proteins such as haptoglobin, hemopexin and vitamin D-binding protein were downregulated compared with the control. The changes in immune, molecular transport and signaling pathways were the most representative in the proteomic profile of the saliva and plasma. This is the first study to describe the proteome of saliva and plasma from the same women with impalpable breast lesions.
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Nipple aspirate fluid (NAF) requires investigation as a potential source of biomarkers for early diagnosis or risk assessment in breast cancer and other breast disorders. The present study demonstrated that proteins were easily extracted from dried NAF spots on Guthrie cards and were suitable for mass spectrometry analysis. NAF was obtained from 80 women, collected on Guthrie cards, between 2007 and 2010. The NAF-proteins were extracted from the card by incubating the card in water. These proteins were then quantified and separated using one-dimensional, 12% SDS-PAGE, gel electrophoresis and on high-resolution gradient gels at different concentrations (4-12, 8-16 and 4-20%). The bands with the most abundant proteins were excised from the gradient gels and the proteins were identified by liquid chromatography quadrupole time of flight. Immunoglobulins, Zn-α2-glicoprotein, apoliprotein D and prolactin inducible protein were among those identified. The NAF-Guthrie card collection method has not been applied previously, however, NAF proteins have been identified using other collecting techniques, confirming the feasibility of the NAF Guthrie card collection method for analyzing the proteins within NAF. The NAF-Guthrie card collecting method has multiple advantages, including being inexpensive, non-invasive, reliable and painless, and the cards can be stored at room temperature. Examining NAF may assist in identifying individuals at a higher risk of breast cancer and in improving patient prognosis.
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Biomarcadores de Tumor/aislamiento & purificación , Neoplasias de la Mama/diagnóstico , Líquido Aspirado del Pezón/química , Proteínas/aislamiento & purificación , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/prevención & control , Cromatografía Liquida , Diagnóstico Precoz , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Glándulas Mamarias Humanas/metabolismo , Glándulas Mamarias Humanas/fisiología , Glándulas Mamarias Humanas/fisiopatología , Espectrometría de Masas , Persona de Mediana Edad , Anotación de Secuencia Molecular , Proteínas/metabolismo , Tiras Reactivas , Extracción en Fase Sólida/métodos , AguaRESUMEN
Early detection of breast cancer increases the chances of cure, but the reliable identification of impalpable lesions is still a challenge. In spite of the advances in breast cancer detection, the molecular basis of impalpable lesions and the corresponding circulating biomarkers are not well understood. Impalpable lesions, classified by radiologists according to the Breast Imaging Reporting and Data System in the categories 3 and 4, can be either benign or malignant (slow growing or aggressive). In this article, we report the DNA methylation pattern in CDKN2A (p14(ARF)/p16(INK4a)) and in ATM gene promoters from 62 impalpable lesions, 39 peripheral blood samples, and 39 saliva samples, assessed by methylation-specific polymerase chain reaction method. ATM showed the greatest percentage of methylation in DNA from lesions (benign and malignant), blood (even with p16(INK4a)), and saliva, followed by p16(INK4a) and p14(ARF). Among the malignant cases, ATM promoter was the most hypermethylated in lesion DNA and in blood and saliva DNAs, and p14(ARF), the least. The highest percentage of p16(INK4a) methylation was found in the blood. Finally, our data are relevant because they were obtained using impalpable breast lesions from patients who were carefully recruited in 2 public hospitals of Rio de Janeiro.
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Proteínas de la Ataxia Telangiectasia Mutada/análisis , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Detección Precoz del Cáncer/métodos , Genes p16 , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de la Ataxia Telangiectasia Mutada/biosíntesis , Neoplasias de la Mama/genética , Metilación de ADN/genética , Femenino , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/genética , Adulto JovenRESUMEN
Introdução: A caracterização das alterações moleculares em lesões mamárias suspeitas para malignidade ainda não são bem definidas. Sabe-se que a detecção precoce do câncer de mama aumenta consideravelmente as chances de cura. Com isso, a busca por marcadores tumorais, a fim de auxiliar no diagnóstico precoce e predizer com confiança se essas lesões são benignas ou malignas, se faz necessária. No processo de carcinogênese, diversas são as alterações de expressão gênica, na qual envolve vários genes-chave que controlam o ciclo celular. Entre os genes, o TP53 tem sido amplamente pesquisado por apresentar mutações e variantes que podem estar envolvidas na carcinogênese mamária. Relato de caso: Paciente do sexo feminino, 45 anos, branca, casada, residente do Estado do Rio de Janeiro com carcinoma ductal in situ grau 2, multifocal. Lesão positiva para os receptores hormonais de estrogênio e progesterona, com ausência de mutação somática e com presença dos variantes 213A→G e 13494G→A no éxon 6 e intron 6 do gene TP53. Conclusão: Embora tenham sido considerados individualmente neutros, não existem estudos que tenham avaliado o efeito sinérgico dos variantes 213A→G e 13494G→A
Introduction:The characterization of molecular alterations in breast lesions suspicious for malignancy is not welldefined.it is known that early detection of breast cancer greatly increases the chances of cure. Thus, it is required the survey for tumor markers may help establish an early diagnosis and confidently predict whether these lesions arebenign or malignant.in the process of carcinogenesis, there are several changes in gene expression, which involvesseveral key genes that control the cell cycle.among the genes,TP53has been widely studied for its mutations andvariations, which may be involved in breast carcinogenesis...