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Small extracellular vesicles (sEVs) in the blood of cancer patients contain higher amounts of tumor markers than those identified as free-circulating. miRNAs have significant biomedical relevance due to their high stability and feasible detection. However, there is no reliable endogenous control available to measure sEVs-miRNA content, impairing the acquisition of standardized consistent measurements in cancer liquid biopsy. In this study, we identified three miRNAs from a panel of nine potential normalizers that emerged from a comprehensive analysis comparing the sEV-miRNA profile of six lung and ovarian human cancer cell lines in the absence of or under different conditions. Their relevance as normalizers was tested in 26 additional human cancer cell lines from nine different tumor types undergoing chemotherapy or radiotherapy treatment. The validation cohorts were comprised of 242 prospective plasma and ascitic fluid samples from three different human tumor types. Variability and normalization properties were tested in comparison to miR-16, the most used control to normalize free-circulating miRNAs in plasma. Our results indicate that miR-151a is consistently represented in small extracellular vesicles with minimal variability compared to miR-16, providing a novel normalizer to measure small extracellular vesicle miRNA content that will benefit liquid biopsy in cancer patients.
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Despite advances in non-small cell lung cancer (NSCLC) research, this is still the most common cancer type that has been diagnosed up to date. microRNAs have emerged as useful clinical biomarkers in both tissue and liquid biopsy. However, there are no reliable predictive biomarkers for clinical use. We evaluated the preclinical use of seven candidate miRNAs previously identified by our group. We collected a total of 120 prospective samples from 88 NSCLC patients. miRNA levels were analyzed via qRT-PCR from tissue and blood samples. miR-124 gene target prediction was performed using RNA sequencing data from our group and interrogating data from 2952 NSCLC patients from two public databases. We found higher levels of all seven miRNAs in tissue compared to plasma samples, except for miR-124. Our findings indicate that levels of miR-124, both free-circulating and within exosomes, are increased throughout the progression of the disease, suggesting its potential as a marker of disease progression in both advanced and early stages. Our bioinformatics approach identified KPNA4 and SPOCK1 as potential miR-124 targets in NSCLC. miR-124 levels can be used to identify early-stage NSCLC patients at higher risk of relapse.
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Carcinoma Pulmonar de Células não Pequenas , Exossomos , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Prognóstico , Estudos Prospectivos , Biomarcadores Tumorais/metabolismo , Recidiva Local de Neoplasia/metabolismo , MicroRNAs/metabolismo , Exossomos/metabolismo , Biópsia Líquida , Proteoglicanas/metabolismo , alfa Carioferinas/metabolismoRESUMO
Platin-based chemotherapy is the standard treatment for patients with non-small cell lung cancer (NSCLC). However, resistance to this therapy is a major obstacle in successful treatment. In this study, we aimed to investigate the impact of several pharmacogenetic variants in patients with unresectable NSCLC treated with platin-based chemotherapy. Our results showed that DPYD variant carriers had significantly shorter progression-free survival and overall survival compared to DPYD wild-type patients, whereas DPD deficiency was not associated with a higher incidence of high-grade toxicity. For the first time, our study provides evidence that DPYD gene variants are associated with resistance to platin-based chemotherapy in NSCLC patients. Although further studies are needed to confirm these findings and explore the underlying mechanisms of this association, our results suggest that genetic testing of DPYD variants may be useful for identifying patients at a higher risk of platin-based chemotherapy resistance and might be helpful in guiding future personalized treatment strategies in NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Di-Hidrouracila Desidrogenase (NADP)/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Fluoruracila/uso terapêutico , Prognóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/induzido quimicamente , Células GerminativasRESUMO
BACKGROUND: Cytosine modifications in DNA such as 5-methylcytosine (5mC) underlie a broad range of developmental processes, maintain cellular lineage specification, and can define or stratify types of cancer and other diseases. However, the wide variety of approaches available to interrogate these modifications has created a need for harmonized materials, methods, and rigorous benchmarking to improve genome-wide methylome sequencing applications in clinical and basic research. Here, we present a multi-platform assessment and cross-validated resource for epigenetics research from the FDA's Epigenomics Quality Control Group. RESULTS: Each sample is processed in multiple replicates by three whole-genome bisulfite sequencing (WGBS) protocols (TruSeq DNA methylation, Accel-NGS MethylSeq, and SPLAT), oxidative bisulfite sequencing (TrueMethyl), enzymatic deamination method (EMSeq), targeted methylation sequencing (Illumina Methyl Capture EPIC), single-molecule long-read nanopore sequencing from Oxford Nanopore Technologies, and 850k Illumina methylation arrays. After rigorous quality assessment and comparison to Illumina EPIC methylation microarrays and testing on a range of algorithms (Bismark, BitmapperBS, bwa-meth, and BitMapperBS), we find overall high concordance between assays, but also differences in efficiency of read mapping, CpG capture, coverage, and platform performance, and variable performance across 26 microarray normalization algorithms. CONCLUSIONS: The data provided herein can guide the use of these DNA reference materials in epigenomics research, as well as provide best practices for experimental design in future studies. By leveraging seven human cell lines that are designated as publicly available reference materials, these data can be used as a baseline to advance epigenomics research.
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Epigênese Genética , Epigenômica/métodos , Controle de Qualidade , 5-Metilcitosina , Algoritmos , Ilhas de CpG , DNA/genética , Metilação de DNA , Epigenoma , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Alinhamento de Sequência , Análise de Sequência de DNA/métodos , Sulfitos , Sequenciamento Completo do Genoma/métodosRESUMO
BACKGROUND: In an effort to contribute to overcoming the platinum resistance exhibited by most solid tumors, we performed an array of epigenetic approaches, integrating next-generation methodologies and public clinical data to identify new potential epi-biomarkers in ovarian cancer, which is considered the most devastating of gynecological malignancies. METHODS: We cross-analyzed data from methylome assessments and restoration of gene expression through microarray expression in a panel of four paired cisplatin-sensitive/cisplatin-resistant ovarian cancer cell lines, along with publicly available clinical data from selected individuals representing the state of chemoresistance. We validated the methylation state and expression levels of candidate genes in each cellular phenotype through Sanger sequencing and reverse transcription polymerase chain reaction, respectively. We tested the biological role of selected targets using an ectopic expression plasmid assay in the sensitive/resistant tumor cell lines, assessing the cell viability in the transfected groups. Epigenetic features were also assessed in 189 primary samples obtained from ovarian tumors and controls. RESULTS: We identified PAX9 and FKBP1B as potential candidate genes, which exhibited epigenetic patterns of expression regulation in the experimental approach. Re-establishment of FKBP1B expression in the resistant OVCAR3 phenotype in which this gene is hypermethylated and inhibited allowed it to achieve a degree of platinum sensitivity similar to the sensitive phenotype. The evaluation of these genes at a translational level revealed that PAX9 hypermethylation leads to a poorer prognosis in terms of overall survival. We also set a precedent for establishing a common epigenetic signature in which the validation of a single candidate, MEST, proved the accuracy of our computational pipelines. CONCLUSIONS: Epigenetic regulation of PAX9 and FKBP1B genes shows that methylation in non-promoter areas has the potential to control gene expression and thus biological consequences, such as the loss of platinum sensitivity. At the translational level, PAX9 behaves as a predictor of chemotherapy response to platinum in patients with ovarian cancer. This study revealed the importance of the transcript-specific study of each gene under potential epigenetic regulation, which would favor the identification of new markers capable of predicting each patient's progression and therapeutic response.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma Epitelial do Ovário/tratamento farmacológico , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Fator de Transcrição PAX9/genética , Compostos de Platina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral/efeitos dos fármacos , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Variação Genética , Humanos , Pessoa de Meia-Idade , EspanhaRESUMO
Identifying the druggable target is crucial for patients with nonsquamous advanced non-small cell lung cancer (NSCLC). This article adds to the spectrum of ROS1 fusion cases described in NSCLC. We describe a novel SLC12A2-ROS1 rearrangement that has not been previously reported in other cancers: a fusion that has clinical and radiological sensitivity to crizotinib. Fluorescence in situ hybridization detected the SLC12A2-ROS1 fusion and it was confirmed through hybrid capture-based next-generation sequencing (NGS); however, the fusion could not be detected by amplicon-based assay. The success of implementing NGS into routine clinical practice depends on the accuracy of testing. The test's methodological features should then be considered because they significantly affect the results. Given this patient's response to crizotinib, identifying patients with undescribed ROS1 fusions has important therapeutic implications. KEY POINTS: This is the first known description of an SLC12A2-ROS1 fusion. Considering the patient's clinical features and tumor response observed after crizotinib therapy, the authors confirm that this new rearrangement has relevant clinical impact for patients with non-small cell lung cancer. The success of implementing next-generation sequencing (NGS) into routine clinical practice depends on the accuracy of the testing. Different assays and NGS platforms can achieve differing results. Each assay's limitations need to be considered to ensure the quality of precision medicine in clinical practice.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Membro 2 da Família 12 de Carreador de SolutoRESUMO
BACKGROUND: The promoter hypermethylation of the methylguanine-DNA methyltransferase gene is a frequently used biomarker in daily clinical practice as it is associated with a favorable prognosis in glioblastoma patients treated with temozolamide. Due to the absence of adequately standardized techniques, international harmonization of the MGMT methylation biomarker is still an unmet clinical need for the diagnosis and treatment of glioblastoma patients. RESULTS: In this study we carried out a clinical validation of a quantitative assay for MGMT methylation detection by comparing a novel quantitative MSP using double-probe (dp_qMSP) with the conventional MSP in 100 FFPE glioblastoma samples. We performed both technologies and established the best cutoff for the identification of positive-methylated samples using the quantitative data obtained from dp_qMSP. Kaplan-Meier curves and ROC time dependent curves were employed for the comparison of both methodologies. CONCLUSIONS: We obtained similar results using both assays in the same cohort of patients, in terms of progression free survival and overall survival according to Kaplan-Meier curves. In addition, the results of ROC(t) curves showed that dp_qMSP increases the area under curve time-dependent in comparison with MSP for predicting progression free survival and overall survival over time. We concluded that dp_qMSP is an alternative methodology compatible with the results obtained with the conventional MSP. Our assay will improve the therapeutic management of glioblastoma patients, being a more sensitive and competitive alternative methodology that ensures the standardization of the MGMT-biomarker making it reliable and suitable for clinical use.
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Biomarcadores Tumorais/genética , Neoplasias Encefálicas/patologia , Glioblastoma/diagnóstico , Glioblastoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/mortalidade , Estudos de Coortes , Ilhas de CpG , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Epigenômica , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/cirurgia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/tendências , Prognóstico , Intervalo Livre de Progressão , Regiões Promotoras Genéticas/genética , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Temozolomida/uso terapêutico , Proteínas Supressoras de Tumor/genéticaRESUMO
X-linked myotubular myopathy (XLMTM; OMIM 310400) is a centronuclear congenital muscular disorder of X-linked recessive inheritance. Although female carriers are typically asymptomatic, affected heterozygous females have been described. Here, we describe the case of a sporadic female patient with suspicion of centronuclear myopathy and a heterozygous large deletion at Xq28 encompassing the MAMLD1, MTM1, MTMR1, CD99L2, and HMGB3 genes. The deletion was first detected using a custom next generation sequencing (NGS)-based multigene panel and finally characterized by comparative genomic hybridization array and multiplex ligation probe assay techniques. In this patient we have confirmed, by MTM1 mRNA quantification, a MTM1 gene expression less than the expected 50 percent in patient muscle. The significant 20% reduction in MTM1 mRNA expression in muscle, precludes low level of the normal myotubularin protein as the cause of the phenotype in this heterozygous female. We have also found that BIN1 expression in patient muscle biopsy was significantly increased, and postulate that BIN1 expression will be increased in XLMTM patient muscle as an attempt to maintain muscle function.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Deleção Cromossômica , Miopatias Congênitas Estruturais/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases não Receptoras/genética , Proteínas Supressoras de Tumor/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adolescente , Cromossomos Humanos X/genética , Feminino , Heterozigoto , Humanos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miopatias Congênitas Estruturais/metabolismo , Miopatias Congênitas Estruturais/patologia , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
The 'cancer cell fusion' theory is controversial due to the lack of methods available to identify hybrid cells and to follow the phenomenon in patients. However, it seems to be one of the best explanations for both the origin and metastasis of primary tumors. Herein, we co-cultured lung cancer stem cells with human monocytes and analyzed the dynamics and properties of tumor-hybrid cells (THC), as well as the molecular mechanisms beneath this fusion process by several techniques: electron-microscopy, karyotyping, CRISPR-Cas9, RNA-seq, immunostaining, signaling blockage, among others. Moreover, mice models were assessed for in vivo characterization of hybrids colonization and invasiveness. Then, the presence of THCs in bloodstream and samples from primary and metastatic lesions were detected by FACS and immunofluorescence protocols, and their correlations with TNM stages established. Our data indicate that the generation of THCs depends on the expression of CD36 on tumor stem cells and the oxidative state and polarization of monocytes, the latter being strongly influenced by microenvironmental fluctuations. Highly oxidized M2-like monocytes show the strongest affinity to fuse with tumor stem cells. THCs are able to proliferate, colonize and invade organs. THC-specific cell surface signature CD36+CD14+PANK+ allows identifying them in matched primary tumor tissues and metastases as well as in bloodstream from patients with lung cancer, thus functioning as a biomarker. THCs levels in circulation correlate with TNM classification. Our results suggest that THCs are involved in both origin and spread of metastatic cells. Furthermore, they might set the bases for future therapies to avoid or eradicate lung cancer metastasis.
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Neoplasias Pulmonares , Monócitos , Células-Tronco Neoplásicas , Animais , Fusão Celular , Humanos , Células Híbridas , CamundongosRESUMO
INTRODUCTION: MicroRNA-7 (miR-7) has a suppressive role in lung cancer and alterations in its DNA methylation may contribute to tumorigenesis. As COPD patients with emphysema have a higher risk of lung cancer than other COPD phenotypes, we compared the miR-7 methylation status among smoker subjects and patients with various COPD phenotypes to identify its main determinants. METHODS: 30 smoker subjects without airflow limitation and 136 COPD patients without evidence of cancer were recruited in a prospective study. Clinical and functional characteristics were assessed and patients were classified into: frequent exacerbator, emphysema, chronic bronchitis and asthma COPD overlap (ACO). DNA collected from buccal epithelial samples was isolated and bisulfite modified. miR-7 methylation status was evaluated by quantitative methylation-specific polymerase chain reaction (qMSP). RESULTS: miR-7 Methylated levels were higher in COPD patients than in smokers without airflow limitation (23.7 ± 12.4 vs. 18.5 ± 8.8 %, p = 0.018). Among COPD patients, those with emphysema had higher values of methylated miR-7 (27.1 ± 10.2 %) than those with exacerbator (19.4 ± 9.9 %, p = 0.004), chronic bronchitis (17.3 ± 9.0 %, p = 0.002) or ACO phenotypes (16.0 ± 7.2 %, p = 0.010). After adjusting for clinical parameters, differences between emphysematous patients and those with other phenotypes were retained. In COPD patients, advanced age, mild-moderate airflow limitation, reduced diffusing capacity and increased functional residual capacity were identified as independent predictors of methylated miR-7 levels. CONCLUSION: The increase of miR-7 methylation levels experienced by COPD patients occurs mainly at the expense of the emphysema phenotype, which might contribute to explain the higher incidence of lung cancer in these patients
INTRODUCCIÓN: El microRNA-7 (miR-7) tiene un papel supresor en el cáncer de pulmón, y las alteraciones en la metilación de su DNA podrían contribuir a la tumorogénesis. Como los pacientes con EPOC y enfisema presentan un mayor riesgo de sufrir cáncer de pulmón frente a otros fenotipos de EPOC, comparamos la metilación de miR-7 entre los pacientes fumadores y los pacientes con varios fenotipos de EPOC para identificar sus factores determinantes principales. MÉTODOS: Se reclutaron para un estudio prospectivo 30 sujetos fumadores sin restricciones en el flujo aéreo y 136 pacientes con EPOC sin evidencia de cáncer. Se valoraron las características clínicas y funcionales y se clasificaron a los pacientes en: exacerbaciones frecuentes, enfisema, bronquitis crónica y solapamiento de asma y EPOC (ACO, por sus siglas en inglés). Se recogió ADN a partir de muestras de epitelio bucal, se aisló y se modificó con bisulfito. El estado de metilación del miR-7 se evaluó mediante la reacción cuantitativa en cadena de la polimerasa específica de la metilación (qMPS por sus siglas en inglés). RESULTADOS: Los niveles de metilación del miR-7 fueron más altos en los pacientes con EPOC que en los fumadores sin restricciones en el flujo aéreo (23,7 ± 12,4 frente a 18,5 ± 8,8%, p = 0,018). Entre los pacientes con EPOC, aquellos con enfisema presentaban valores más altos de miR-7 metilado (27,1 ± 10,2%) que aquellos con exacerbaciones (19,4 ± 9,9%, p = 0,004), bronquitis crónica (17,3 ± 9,0%, p = 0,002) o los fenotipos ACO (16,0 ± 7,2%, p = 0,010). Tras ajustar los resultados a los parámetros clínicos, las diferencias entre los pacientes enfisematosos y aquellos con otros fenotipos permanecieron. En los pacientes con EPOC, se identificaron como predictores independientes de los niveles de metilación del miR-7 a: la edad avanzada, limitación al flujo aéreo leve-moderada, capacidad de difusión reducida y capacidad residual funcional aumentada. CONCLUSIÓN: El aumento de los niveles de metilación del miR-7 que experimentan los pacientes con EPOC ocurre principalmente a expensas del fenotipo con enfisema, lo que podría contribuir a explicar la mayor incidencia de cáncer de pulmón en estos pacientes
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Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Metilação , MicroRNAs/metabolismo , Enfisema Pulmonar/metabolismo , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Estudos Prospectivos , FenótipoRESUMO
Cancer is one of the leading causes of death worldwide and it can affect any part of the organism. It arises as a consequence of the genetic and epigenetic changes that lead to the uncontrolled growth of the cells. The epigenetic machinery can regulate gene expression without altering the DNA sequence, and it comprises methylation of the DNA, histones modifications, and non-coding RNAs. Alterations of these gene-expression regulatory elements can be produced by an imbalance of the intracellular environment, such as the one derived by oxidative stress, to promote cancer development, progression, and resistance to chemotherapeutic treatments. Here we review the current literature on the effect of oxidative stress in the epigenetic machinery, especially over the largely unknown ncRNAs and its consequences toward cancer development and progression.
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Despite often leading to platinum resistance, platinum-based chemotherapy continues to be the standard treatment for many epithelial tumors. In this study we analyzed and validated the cytogenetic alterations that arise after treatment in four lung and ovarian paired cisplatin-sensitive/resistant cell lines by 1-million microarray-based comparative genomic hybridization (array-CGH) and qRT-PCR methodologies. RNA-sequencing, functional transfection assays, and gene-pathway activity analysis were used to identify genes with a potential role in the development of this malignancy. The results were further explored in 55 lung and ovarian primary tumors and control samples, and in two extensive in silico databases. Long-term cell exposure to platinum induces the frequent deletion of ITF2 gene. Its expression re-sensitized tumor cells to platinum and recovered the levels of Wnt/ß-catenin transcriptional activity. ITF2 expression was also frequently downregulated in epithelial tumors, predicting a worse overall survival. We also identified an inverse correlation between ITF2 and HOXD9 expression, revealing that Non-small cell lung cancer (NSCLC) patients with lower expression of HOXD9 had a better overall survival rate. We defined the implication of ITF2 as a molecular mechanism behind the development of cisplatin resistance probably through the activation of the Wnt-signaling pathway. This data highlights the possible role of ITF2 and HOXD9 as novel therapeutic targets for platinum resistant tumors.
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INTRODUCTION: MicroRNA-7 (miR-7) has a suppressive role in lung cancer and alterations in its DNA methylation may contribute to tumorigenesis. As COPD patients with emphysema have a higher risk of lung cancer than other COPD phenotypes, we compared the miR-7 methylation status among smoker subjects and patients with various COPD phenotypes to identify its main determinants. METHODS: 30 smoker subjects without airflow limitation and 136 COPD patients without evidence of cancer were recruited in a prospective study. Clinical and functional characteristics were assessed and patients were classified into: frequent exacerbator, emphysema, chronic bronchitis and asthma COPD overlap (ACO). DNA collected from buccal epithelial samples was isolated and bisulfite modified. miR-7 methylation status was evaluated by quantitative methylation-specific polymerase chain reaction (qMSP). RESULTS: miR-7 Methylated levels were higher in COPD patients than in smokers without airflow limitation (23.7±12.4 vs. 18.5±8.8%, p=0.018). Among COPD patients, those with emphysema had higher values of methylated miR-7 (27.1±10.2%) than those with exacerbator (19.4±9.9%, p=0.004), chronic bronchitis (17.3±9.0%, p=0.002) or ACO phenotypes (16.0±7.2%, p=0.010). After adjusting for clinical parameters, differences between emphysematous patients and those with other phenotypes were retained. In COPD patients, advanced age, mild-moderate airflow limitation, reduced diffusing capacity and increased functional residual capacity were identified as independent predictors of methylated miR-7 levels. CONCLUSION: The increase of miR-7 methylation levels experienced by COPD patients occurs mainly at the expense of the emphysema phenotype, which might contribute to explain the higher incidence of lung cancer in these patients.
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Enfisema , MicroRNAs , Doença Pulmonar Obstrutiva Crônica , Metilação de DNA , Humanos , MicroRNAs/genética , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/genéticaRESUMO
Non-small-cell lung cancer (NSCLC) is the most common malignancy worldwide. Platinum-based chemotherapy is the standard of care for these patients. Recent research showed that miR-7 methylation status is a biomarker of cisplatin resistance in lung and ovarian cancer cells, which is one of the major limitations associated with their clinical management. The aim of the present study is to provide clinical insights associated with this novel potential biomarker in NSCLC patients by comparing the miR-7 methylation status with the cisplatin treatment response. Our results analyzed in 81 samples show that miR-7 methylation is a common event in tumor tissue and it is more frequent as the stage of the disease advances, remaining in 75% of metastatic patients. Tumor miR-7 unmethylation trend to a better PFS in early stages, and when our data was validated in an extended "in silico" cohort of 969 patients we obtained a significant increment in PFS and OS in those patients harboring miR-7 unmethylated (p = 0.010 and p = 0.007 respectively). When we select those early-stages patients harbouring miR-7 methylation, we observed that adenocarcinoma patients present a dramatic decrease in PFS compared with squamous cell carcinoma patients (median 18.9 versus 59.7 months, p = 0.002). In conclusion, our results show that presence of miR-7 methylation in early-stage NSCLC is suggestive of aggressive behavior, especially for adenocarcinoma patients. One major challenge in early diagnosis in NSCLC is identify the subgroup of patients that could benefit for adjuvant therapy, our data establish the basis for epigenetic classification on early-stage NSCLC that could influence treatment decisions in the future.
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Familial hypercholesterolemia is an autosomal dominant disease of lipid metabolism caused by defects in the genes LDLR, APOB, and PCSK9. The prevalence of heterozygous familial hypercholesterolemia (HeFH) is estimated between 1/200 and 1/250. Early detection of patients with FH allows initiation of treatment, thus reducing the risk of coronary heart disease. In this study, we performed in vitro characterization of new LDLR variants found in our patients. Genetic analysis was performed by Next Generation Sequencing using a customized panel of 198 genes in DNA samples of 516 subjects with a clinical diagnosis of probable or definitive FH. All new LDLR variants found in our patients were functionally validated in CHO-ldlA7 cells. The LDLR activity was measured by flow cytometry and LDLR expression was detected by immunofluorescence. Seven new variants at LDLR were tested: c.518 G>C;p.(Cys173Ser), c.[684 G>T;694 G>T];p.[Glu228Asp;Ala232Ser], c.926C>A;p.(Pro309His), c.1261A>G;p.(Ser421Gly), c.1594T>A;p.(Tyr532Asn), and c.2138delC;p.(Thr713Lysfs*17). We classified all variants as pathogenic except p.(Ser421Gly) and p.(Ala232Ser). The functional in vitro characterization of rare variants at the LDLR is a useful tool to classify the new variants. This approach allows us to confirm the genetic diagnosis of FH, avoiding the classification as "uncertain significant variants", and therefore, carry out cascade family screening.
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Sequenciamento de Nucleotídeos em Larga Escala/métodos , Hiperlipoproteinemia Tipo II/diagnóstico , Mutação , Receptores de LDL/genética , Receptores de LDL/metabolismo , Adolescente , Adulto , Idoso , Animais , Células CHO , Criança , Cricetulus , Diagnóstico Precoce , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA/métodos , Adulto JovemRESUMO
DUSP6/MKP3 is a dual-specific phosphatase that regulates extracellular regulated kinase ERK1/2 and ERK5 activity, with an increasingly recognized role as tumor suppressor. In silico studies from Gene expression Omnibus (GEO) and Cancer Genome atlas (TCGA) databases reveal poor prognosis in those Non-small cell lung cancer (NSCLC) patients with low expression levels of DUSP6. In agreement with these data, here we show that DUSP6 plays a major role in the regulation of cell migration, motility and tumor growth. We have found upregulation in the expression of several genes involved in epithelial to mesenchymal transition (EMT) in NSCLC-DUSP6 depleted cells. Data obtained in RNA-seq studies carried out in DUSP6 depleted cells identified EGFR, TGF-ß and WNT signaling pathways and several genes such as VAV3, RUNXR2, LEF1, FGFR2 whose expression is upregulated in these cells and therefore affecting cellular functions such as integrin mediated cell adhesion, focal adhesion and motility. Furthermore, EGF signaling pathway is activated via ERK5 and not ERK1/2 and TGF-ß via SMAD2/3 in DUSP6 depleted cells. In summary DUSP6 is a tumor suppressor in NSCLC and re-establishment of its expression may be a potential strategy to revert poor outcome in NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/genética , Fosfatase 6 de Especificidade Dupla/genética , Genes Supressores de Tumor , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Citoesqueleto de Actina/metabolismo , Adenocarcinoma de Pulmão/enzimologia , Adenocarcinoma de Pulmão/patologia , Junções Aderentes/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Forma Celular/genética , Progressão da Doença , Fosfatase 6 de Especificidade Dupla/metabolismo , Adesões Focais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases , Camundongos Nus , Fator de Crescimento Transformador beta/metabolismoRESUMO
Information from proteomics, microscopy, and structural biology are integrated to create structural models of exosomes, small vesicles released from cells. Three visualization methods are employed and compared: 2D painting of a cross section using traditional media, manual creation of a cross section using the mesoscale 2.5D digital painting software cellPAINT, and generation of a 3D atomic model using the mesoscale modeling program cellPACK.
RESUMO
Adjuvant chemotherapy for solid tumors based on platinum-derived compounds such as cisplatin is the treatment of choice in most cases. Cisplatin triggers signaling pathways that lead to cell death, but it also induces changes in tumor cells that modify the therapeutic response, thereby leading to cisplatin resistance. We have recently reported that microRNA-7 is silenced by DNA methylation and is involved in the resistance to platinum in cancer cells through the action of the musculoaponeurotic fibrosarcoma oncogene family, protein G (MAFG). In the present study, we first confirm the miR-7 epigenetic regulation of MAFG in 44 normal- and/or tumor-paired samples in non-small-cell lung cancer (NSCLC). We also provide translational evidence of the role of MAFG and the clinical outcome in NSCLC by the interrogation of two extensive in silico databases of 2019 patients. Moreover, we propose that MAFG-mediated resistance could be conferred due to lower reactive oxygen species production after cisplatin exposure. We developed specifically selected aptamers against MAFG, with high sensitivity to detect the protein at a nuclear level probed by aptacytochemistry and histochemistry analyses. The inhibition of MAFG activity through the action of the specific aptamer apMAFG6F increased the levels of reactive oxygen species production and the sensitivity to cisplatin. We report first the specific nuclear identification of MAFG as a novel detection method for diagnosis in NSCLC, and then we report that MAFG modulates the redox response and confers cell protection against free radicals generated after platinum administration, thus also being a promising therapeutic target.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Fator de Transcrição MafG/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Clonagem Molecular , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , Epigênese Genética/genética , Expressão Gênica , Inativação Gênica , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Fator de Transcrição MafG/genética , Fator de Transcrição MafG/fisiologia , MicroRNAs/genética , MicroRNAs/fisiologia , Oxirredução , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/fisiologia , Análise de Sequência de DNA , TransfecçãoRESUMO
Long noncoding RNAs (lncRNAs) are critical regulators of cell biology whose alteration can lead to the development of diseases such as cancer. The potential role of lncRNAs and their epigenetic regulation in response to platinum treatment are largely unknown. We analyzed four paired cisplatin-sensitive/resistant non-small cell lung cancer and ovarian cancer cell lines. The epigenetic landscape of overlapping and cis-acting lncRNAs was determined by combining human microarray data on 30,586 lncRNAs and 20,109 protein coding mRNAs with whole-genome bisulfite sequencing. Selected candidate lncRNAs were further characterized by PCR, gene-ontology analysis, and targeted bisulfite sequencing. Differential expression in response to therapy was observed more frequently in cis-acting than in overlapping lncRNAs (78% vs. 22%, fold change ≥1.5), while significantly altered methylation profiles were more commonly associated with overlapping lncRNAs (29% vs. 8%; P value <0.001). Moreover, overlapping lncRNAs contain more CpG islands (CGIs) (25% vs. 17%) and the majority of CGI-containing overlapping lncRNAs share these CGIs with their associated coding genes (84%). The differences in expression between sensitive and resistant cell lines were replicated in 87% of the selected candidates (P<0.05), while our bioinformatics approach identifying differential methylation was confirmed in all of the selected lncRNAs (100%). Five lncRNAs under epigenetic regulation appear to be involved in cisplatin resistance (AC091814.2, AC141928.1, RP11-65J3.1-002, BX641110, and AF198444). These novel findings provide new insights into epigenetic mechanisms and acquired resistance to cisplatin that highlight specific lncRNAs, some with unknown function, that may signal strategies in epigenetic therapies.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Epigênese Genética , Neoplasias Ovarianas/tratamento farmacológico , RNA Longo não Codificante/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Cisplatino/efeitos adversos , Cisplatino/farmacologia , Biologia Computacional , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Análise em Microsséries , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , RNA Mensageiro/genética , Sequenciamento Completo do GenomaRESUMO
The elucidation of mechanisms involved in resistance to therapies is essential to improve the survival of patients with malignant gliomas. A major feature possessed by glioma cells that may aid their ability to survive therapy and reconstitute tumors is the capacity for self-renewal. We show here that glioma stem cells (GSCs) express low levels of MKP1, a dual-specificity phosphatase, which acts as a negative inhibitor of JNK, ERK1/2, and p38 MAPK, while induction of high levels of MKP1 expression are associated with differentiation of GSC. Notably, we find that high levels of MKP1 correlate with a subset of glioblastoma patients with better prognosis and overall increased survival. Gain of expression studies demonstrated that elevated MKP1 impairs self-renewal and induces differentiation of GSCs while reducing tumorigenesis in vivo. Moreover, we identified that MKP1 is epigenetically regulated and that it mediates the anti-tumor activity of histone deacetylase inhibitors (HDACIs) alone or in combination with temozolomide. In summary, this study identifies MKP1 as a key modulator of the interplay between GSC self-renewal and differentiation and provides evidence that the activation of MKP1, through epigenetic regulation, might be a novel therapeutic strategy to overcome therapy resistance in glioblastoma.