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1.
Cell Mol Neurobiol ; 43(2): 813-826, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35366170

RESUMO

Medulloblastoma is the most common type of pediatric malignant primary brain tumor, and about one-third of patients die due to disease recurrence and most survivors suffer from long-term side effects. MB is clinically, genetically, and epigenetically heterogeneous and subdivided into at least four molecular subgroups: WNT, SHH, Group 3, and Group 4. We evaluated common differentially expressed genes between a Brazilian RNA-seq GSE181293 dataset and microarray GSE85217 dataset cohort of pediatric MB samples using bioinformatics methodology in order to identify hub genes of the molecular subgroups based on PPI network construction, survival and functional analysis. The main finding was the identification of five hub genes from the WNT subgroup that are tumor suppressors, and whose lower expression is related to a worse prognosis for MB patients. Furthermore, the common genes correlated with the five tumor suppressors participate in important pathways and processes for tumor initiation and progression, as well as development and differentiation, and some of them control cell stemness and pluripotency. These genes have not yet been studied within the context of MB, representing new important elements for investigation in the search for therapeutic targets, prognostic markers or for understanding of MB biology.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Meduloblastoma , Humanos , Criança , Meduloblastoma/genética , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Prognóstico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética
2.
J Toxicol Environ Health A ; 86(21): 803-815, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37565650

RESUMO

Nosocomial infections (NIs) appear in patients under medical care in the hospital. The surveillance of the bacterial communities employing high-resolution 16S rRNA profiling, known as metabarcoding, represents a reliable method to establish factors that may influence the composition of the bacterial population during NIs. The present study aimed to utilize high-resolution 16S rRNA profiling to identify high bacterial diversity by analyzing 11 inside and 10 outside environments from the General Hospital of Ribeirão Preto Medical School, Brazil. Our results identified a high bacterial diversity, and among these, the most abundant bacterial genera linked to NIs were Cutibacterium, Streptococcus, Staphylococcus, and Corynebacterium. A Acinetobacter was detected in cafeterias, bus stops, and adult and pediatric intensive care units (ICUs). Data suggest an association between transport and alimentation areas proximal to the hospital ICU environment. Interestingly, the correlation and clusterization analysis showed the potential of the external areas to directly influence the ICU pediatric department microbial community, including the outpatient's clinic, visitor halls, patient reception, and the closest cafeterias. Our results demonstrate that high-resolution 16S rRNA profiling is a robust and reliable tool for bacterial genomic surveillance. In addition, the metabarcoding approach might help elaborate decontamination policies, and consequently reduce NIs.


Assuntos
Infecção Hospitalar , Microbiota , Adulto , Criança , Humanos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , RNA Ribossômico 16S/genética , Bactérias/genética , Hospitais
3.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445965

RESUMO

Breast cancer is responsible for 25% of all cancers that affect women. Due to its high heterogeneity pattern in clinical diagnosis and its molecular profile differences, researchers have been seeking new targets and therapies, with more specificity and fewer side effects. Thus, one compound that has garnered our attention is trans-chalcone, which is naturally occurring in various plants and possesses promising biological properties, including antitumor effects. MiRNA is an extensive class of non-coding small, endogenous, and single-stranded RNAs, and it is involved in post-translational gene regulation. Therefore, the objective of this study was to investigate the effects of TChal on miRNAs expression and its relationship with anticancer activity against MCF-7. Initially, the trans-chalcone IC50 value was established by MTT assay for MCF-7and HaCat (non-cancer cell), in which we found out that it was 53.73 and 44.18 µM, respectively. Subsequently, we treated MCF-7 cells with trans-chalcone at its IC50 concentration and performed Mi-seq analysis, which unveiled 23 differentially expressed miRNAs. From this set, we selected five miRNAs (miR-25-5p, miR-27a-3p, miR-891a, miR-449a, and miR-4485) for further validation using qRT-PCR, guided by in silico analysis and their known association with tumorigenesis. In conclusion, our research provides valuable insights into the potential use of TChal to reveal MicroRNAs molecular targets that can be applied in breast cancer therapy.


Assuntos
Neoplasias da Mama , Chalconas , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Células MCF-7 , Chalconas/farmacologia , Chalconas/uso terapêutico , Regulação Neoplásica da Expressão Gênica
4.
J Cell Mol Med ; 26(3): 671-683, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35040264

RESUMO

Our previous work using a melanoma progression model composed of melanocytic cells (melanocytes, primary and metastatic melanoma samples) demonstrated various deregulated genes, including a few known lncRNAs. Further analysis was conducted to discover novel lncRNAs associated with melanoma, and candidates were prioritized for their potential association with invasiveness or other metastasis-related processes. In this sense, we found the intergenic lncRNA U73166 (ENSG00000230454) and decided to explore its effects in melanoma. For that, we silenced the lncRNA U73166 expression using shRNAs in a melanoma cell line. Next, we experimentally investigated its functions and found that migration and invasion had significantly decreased in knockdown cells, indicating an essential association of lncRNA U73166 for cancer processes. Additionally, using naïve and vemurafenib-resistant cell lines and data from a patient before and after resistance, we found that vemurafenib-resistant samples had a higher expression of lncRNA U73166. Also, we retrieved data from the literature that indicates lncRNA U73166 may act as a mediator of RNA processing and cell invasion, probably inducing a more aggressive phenotype. Therefore, our results suggest a relevant role of lncRNA U73166 in metastasis development. We also pointed herein the lncRNA U73166 as a new possible biomarker or target to help overcome clinical vemurafenib resistance.


Assuntos
Melanoma , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação para Cima/genética , Vemurafenib/farmacologia
5.
Int J Mol Sci ; 23(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36232817

RESUMO

Given the importance of menstrual blood in the pathogenesis of endometriosis and the multifunctional roles of menstrual mesenchymal stem cells (MenSCs) in regenerative medicine, this issue has gained prominence in the scientific community. Moreover, recent reviews highlight how robust the integrated assessment of omics data are for endometriosis. To our knowledge, no study has applied the multi-omics approaches to endometriosis MenSCs. This is a case-control study at a university-affiliated hospital. MenSCs transcriptome and proteome data were obtained by RNA-seq and UHPLC-MS/MS detection. Among the differentially expressed proteins and genes, we emphasize ATF3, ID1, ID3, FOSB, SNAI1, NR4A1, EGR1, LAMC3, and ZFP36 genes and MT2A, TYMP, COL1A1, COL6A2, and NID2 proteins that were already reported in the endometriosis. Our functional enrichment analysis reveals integrated modulating signaling pathways such as epithelial-mesenchymal transition (↑) and PI3K signaling via AKT to mTORC1 (↓ in proteome), mTORC1 signaling, TGF beta signaling, TNFA signaling via NFkB, IL6 STAT3 signaling, and response to hypoxia via HIF1A targets (↑ in transcriptome). Our findings highlight primary changes in the endometriosis MenSCs, suggesting that the chronic inflammatory endometrial microenvironment can modulate these cells, providing opportunities for endometriosis etiopathogenesis. Moreover, they identify challenges for future research leveraging knowledge for regenerative and precision medicine in endometriosis.


Assuntos
Endometriose , Células-Tronco Mesenquimais , Estudos de Casos e Controles , Proliferação de Células , Endometriose/patologia , Feminino , Humanos , Interleucina-6 , Laminina , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Menstruação , Células-Tronco Mesenquimais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteoma , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espectrometria de Massas em Tandem , Transcriptoma , Fator de Crescimento Transformador beta/genética
6.
Genet Mol Biol ; 45(1): e20210309, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35266951

RESUMO

Our goal was to describe in more detail the evolutionary history of Gamma and two derived lineages (P.1.1 and P.1.2), which are part of the arms race that SARS-CoV-2 wages with its host. A total of 4,977 sequences of the Gamma strain of SARS-CoV-2 from Brazil were analyzed. We detected 194 sites under positive selection in 12 genes/ORFs: Spike, N, M, E, ORF1a, ORF1b, ORF3, ORF6, ORF7a, ORF7b, ORF8, and ORF10. Some diagnostic sites for Gamma lacked a signature of positive selection in our study, but these were not fixed, apparently escaping the action of purifying selection. Our network analyses revealed branches leading to expanding haplotypes with sites under selection only detected when P.1.1 and P.1.2 were considered. The P.1.2 exclusive haplotype H_5 originated from a non-synonymous mutational step (H3509Y) in H_1 of ORF1a. The selected allele, 3509Y, represents an adaptive novelty involving ORF1a of P.1. Finally, we discuss how phenomena such as epistasis and antagonistic pleiotropy could limit the emergence of new alleles (and combinations thereof) in SARS-COV-2 lineages, maintaining infectivity in humans, while providing rapid response capabilities to face the arms race triggered by host immuneresponses.

7.
BMC Genomics ; 22(1): 624, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416858

RESUMO

BACKGROUND: Finding meaningful gene-gene interaction and the main Transcription Factors (TFs) in co-expression networks is one of the most important challenges in gene expression data mining. RESULTS: Here, we developed the R package "CeTF" that integrates the Partial Correlation with Information Theory (PCIT) and Regulatory Impact Factors (RIF) algorithms applied to gene expression data from microarray, RNA-seq, or single-cell RNA-seq platforms. This approach allows identifying the transcription factors most likely to regulate a given network in different biological systems - for example, regulation of gene pathways in tumor stromal cells and tumor cells of the same tumor. This pipeline can be easily integrated into the high-throughput analysis. To demonstrate the CeTF package application, we analyzed gastric cancer RNA-seq data obtained from TCGA (The Cancer Genome Atlas) and found the HOXB3 gene as the second most relevant TFs with a high regulatory impact (TFs-HRi) regulating gene pathways in the cell cycle. CONCLUSION: This preliminary finding shows the potential of CeTF to list master regulators of gene networks. CeTF was designed as a user-friendly tool that provides many highly automated functions without requiring the user to perform many complicated processes. It is available on Bioconductor ( http://bioconductor.org/packages/CeTF ) and GitHub ( http://github.com/cbiagii/CeTF ).


Assuntos
Teoria da Informação , Fatores de Transcrição , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Software , Fatores de Transcrição/genética
8.
Tumour Biol ; 43(1): 263-278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34633333

RESUMO

BACKGROUND: Expression dysregulation of HOX homeobox genes has been observed in several cancers, including head and neck squamous cell carcinoma (HNSC). Although characterization of HOX gene roles in HNSC development has been reported, there is still a need to better understand their real contribution to tumorigenesis. OBJECTIVE: The present study aimed to evaluate the contribution of the protein-coding HOX genes (HOXA10, HOXC9, HOXC10, and HOXC13) in cellular processes related to carcinogenesis and progression of the HNSC. METHODS: Expression of HOX genes was analyzed in HNSC RNA-Seq data from The Cancer Genome Atlas (TCGA) and by RT-qPCR in different tumor cell lines. siRNA-mediated knockdown of HOXA10, HOXC9, HOXC10 or HOXC13 was performed in HNSC cell lines, and predicted transcriptional targets HOX genes was analyzed by bioinformatic. RESULTS: Thirty-one out of the 39 mammalian HOX genes were found upregulated in HNSC tissues and cell lines. The HOXC9, HOXC10 or HOXC13 knockdown attenuated cell migration, and lead to downregulation of epithelial-mesenchymal transition (EMT) markers, which were predicted as transcriptional targets of these three HOX genes. Diminished colony formation and cell cycle arrest after HOXC10 or HOXC13 knockdown were also observed, corroborating the fact that there was an enrichment for genes in proliferation/cell cycle pathways. CONCLUSIONS: In summary, we revealed roles for HOXC9, HOXC10, and HOXC13 in cell migration and proliferation/cell cycle progression in HNSC cells and suggested that those HOX members contribute to HNSC development possibly by regulating tumor growth and metastasis.


Assuntos
Genes Homeobox/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Biomarcadores Tumorais/genética , Carcinogênese/genética , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Regulação para Cima
9.
BMC Cancer ; 21(1): 207, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648461

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide; it is the fourth leading cause of death in the world and the third in Brazil. Mutations in the APC, DCC, KRAS and TP53 genes have been associated with the progression of sporadic CRC, occurring at defined pathological stages of the tumor progression and consequently modulating several genes in the corresponding signaling pathways. Therefore, the identification of gene signatures that occur at each stage during the CRC progression is critical and can present an impact on the diagnosis and prognosis of the patient. In this study, our main goal was to determine these signatures, by evaluating the gene expression of paired colorectal adenoma and adenocarcinoma samples to identify novel genetic markers in association to the adenoma-adenocarcinoma stage transition. METHODS: Ten paired adenoma and adenocarcinoma colorectal samples were subjected to microarray gene expression analysis. In addition, mutations in APC, KRAS and TP53 genes were investigated by DNA sequencing in paired samples of adenoma, adenocarcinoma, normal tissue, and peripheral blood from ten patients. RESULTS: Gene expression analysis revealed a signature of 689 differentially expressed genes (DEG) (fold-change> 2, p< 0.05), between the adenoma and adenocarcinoma paired samples analyzed. Gene pathway analysis using the 689 DEG identified important cancer pathways such as remodeling of the extracellular matrix and epithelial-mesenchymal transition. Among these DEG, the ETV4 stood out as one of the most expressed in the adenocarcinoma samples, further confirmed in the adenocarcinoma set of samples from the TCGA database. Subsequent in vitro siRNA assays against ETV4 resulted in the decrease of cell proliferation, colony formation and cell migration in the HT29 and SW480 colorectal cell lines. DNA sequencing analysis revealed KRAS and TP53 gene pathogenic mutations, exclusively in the adenocarcinomas samples. CONCLUSION: Our study identified a set of genes with high potential to be used as biomarkers in CRC, with a special emphasis on the ETV4 gene, which demonstrated involvement in proliferation and migration.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Neoplasias Colorretais/genética , Genes Neoplásicos , Proteínas de Neoplasias/fisiologia , Proteínas Proto-Oncogênicas c-ets/fisiologia , Adenocarcinoma/química , Adenocarcinoma/patologia , Adenoma/química , Adenoma/patologia , Idoso , Biomarcadores Tumorais/genética , Brasil , Divisão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/química , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-ets/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-ets/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Análise Serial de Tecidos , Transcriptoma , Ensaio Tumoral de Célula-Tronco
10.
Reprod Biomed Online ; 42(5): 952-962, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33736992

RESUMO

RESEARCH QUESTION: Is the transcriptome of cumulus cells of infertile women with advanced endometriosis (EIII/IV), with and without endometrioma, altered? DESIGN: In this prospective case-control study, next-generation RNA sequencing was used to compare the transcript profile of cumulus cells among infertile patients undergoing ovarian stimulation for intracytoplasmic sperm injection with EIII/IV, with (n = 9) and without endometrioma (n = 9), and controls (n = 9). An in-silico enrichment analysis was conducted to establish the possibly altered pathways in cumulus cells of patients with endometriosis. RESULTS: Most of the differentially expressed genes (DEG) were found when cumulus cells from women with EIII/IV with endometrioma were compared with controls (DEG, n = 461). In women with EIII/IV without endometrioma, only 66 DEG were verified compared with controls. The enrichment analysis showed that some DEG in cumulus cells of endometriosis are involved in important pathways for the oocyte competence acquisition, such as oxidative phosphorylation, metabolism, mitochondrial function, acetylation and steroid biosynthesis. No DEG were found when cumulus cells from women with EIII/IV with and without endometrioma were compared. CONCLUSION: RNA sequencing results suggest that cumulus cells of infertile women with EIII/IV have an altered transcriptome, regardless of endometrioma. The present findings offer a better understanding of the genes and molecular mechanisms that may be involved in endometriosis-related infertility, mostly in the oocyte competence acquisition process.


Assuntos
Células do Cúmulo/metabolismo , Endometriose/metabolismo , Infertilidade Feminina/metabolismo , Transcriptoma , Adulto , Estudos de Casos e Controles , Endometriose/complicações , Feminino , Perfilação da Expressão Gênica , Humanos , Infertilidade Feminina/etiologia , Estudos Prospectivos , Adulto Jovem
11.
Nucleic Acids Res ; 47(20): 10662-10677, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31586400

RESUMO

While biallelic mutations in the PALB2 tumor suppressor cause Fanconi anemia subtype FA-N, monoallelic mutations predispose to breast and familial pancreatic cancer. Although hundreds of missense variants in PALB2 have been identified in patients to date, only a few have clear functional and clinical relevance. Herein, we investigate the effects of 44 PALB2 variants of uncertain significance found in breast cancer patients and provide detailed analysis by systematic functional assays. Our comprehensive functional analysis reveals two hotspots for potentially deleterious variations within PALB2, one at each terminus. PALB2 N-terminus variants p.P8L [c.23C>T], p.Y28C [c.83A>G], and p.R37H [c.110G>A] compromised PALB2-mediated homologous recombination. At the C-terminus, PALB2 variants p.L947F [c.2841G>T], p.L947S [c.2840T>C], and most strikingly p.T1030I [c.3089C>T] and p.W1140G [c.3418T>C], stood out with pronounced PARP inhibitor sensitivity and cytoplasmic accumulation in addition to marked defects in recruitment to DNA damage sites, interaction with BRCA2 and homologous recombination. Altogether, our findings show that a combination of functional assays is necessary to assess the impact of germline missense variants on PALB2 function, in order to guide proper classification of their deleteriousness.


Assuntos
Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Mutação de Sentido Incorreto/genética , Linhagem Celular Tumoral , Simulação por Computador , Dano ao DNA , Feminino , Loci Gênicos , Recombinação Homóloga/genética , Humanos , Cinética , Rad51 Recombinase/metabolismo , Reprodutibilidade dos Testes
12.
Metab Brain Dis ; 36(7): 1717-1727, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34406559

RESUMO

Worldwide, the excessive consumption of fat and/or sugar has increased considerably. Palatable high-fat diets (HFDs) lead to metabolic disturbances and obesity, and impact emotional and cognitive processes. Previous studies in rodent models suggested that HFDs often cause multiple behavioral alterations, such as learning and memory deficits, and anxiety-like behaviors. Different sexes imply different behavioral and cognitive abilities; yet, most of these studies dealt with male or ovariectomized rats. We evaluated HFD effects in female rats submitted to different behavioral tasks, considering the effects of endogenous hormonal variations throughout estrous cycle. Female Wistar rats in each phase of the estrous cycle using commercial chow (CC) or HFD for 32 days. During treatment, behavioral assessments using sucrose preference (SP), elevated plus-maze (EPM), open field (OF) and novel-object recognition (NOR). At the end of the behavioral tests, animals were euthanized, and performed an immunohistochemical analysis of the brains by brain-derived neurotrophic factor (BDNF) and tyrosine hydroxylase (TH). The main results demonstrated that (1) HFD-fed rats had higher body mass gain and food intake, without altering caloric intake, (2) rats in diestrus had lower sucrose intake, (3) females in metestrus and diestrus showed deficits in the novel-object recognition memory. Furthermore, TH-immunoreactivity decreased in the dorsal striatum and BDNF in the hippocampus in HFD-fed females. These results suggest that HFD alters neurochemical and metabolic aspects that may induce phase-dependent behavioral changes in female rats.


Assuntos
Ansiedade/etiologia , Dieta Hiperlipídica/efeitos adversos , Ciclo Estral/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/sangue , Cognição , Emoções , Ingestão de Energia , Feminino , Atividade Motora , Ratos , Ratos Wistar , Tirosina 3-Mono-Oxigenase/sangue
13.
Sensors (Basel) ; 21(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34372184

RESUMO

This work reports on a reduced graphene oxide and poly(aniline) composite (rGO-PANI), with rGO clusters inserted between PANI chains. These clusters were formed due the plasticizing effect of N-methyl-2-pyrrolidone (NMP) solvent, which was added during the synthesis. Further, this composite was processed as thin film onto an interdigitated electrode array and used as the sensitive layer for ammonia gas, presenting sensitivity of 250% at 100 ppm, a response time of 97 s, and a lowest detection limit of 5 ppm. The PANI deprotonation process, upon exposure to NH3, rGO, also contributed by improving the sensitivity due its higher surface area and the presence of carboxylic acids. This allowed for the interaction between the hydrogen of NH3 (nucleophilic character) and the -COOH groups (electrophilic character) from the rGO surface, thereby introducing a promising sensing composite for amine-based gases.


Assuntos
Grafite , Amônia , Eletrodos , Gases
14.
Nano Lett ; 20(7): 5081-5089, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32492348

RESUMO

Here we use triple-cation metal-organic halide perovskite single crystals for the transistor channel of a flash memory device. Moreover, we design and demonstrate a 10 nm thick single-layer nanofloating gate. It consists of a ternary blend of two organic semiconductors, a p-type polyfluorene and an n-type fullerene that form a donor:acceptor interpenetrating network that serves as the charge storage unit, and of an insulating polystyrene that acts as the tunneling dielectric. Under such a framework, we realize the first non-volatile flash memory transistor based on a perovskite channel. This simplified, solution-processed perovskite flash memory displays unique performance metrics such as a large memory window of 30 V, an on/off ratio of 9 × 107, short write/erase times of 50 ms, and a satisfactory retention time exceeding 106 s. The realization of the first flash memory transistor using a single-crystal perovskite channel could be a valuable direction for perovskite electronics research.

15.
Tumour Biol ; 42(5): 1010428320918050, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32456563

RESUMO

Homeobox genes function as master regulatory transcription factors during development, and their expression is often altered in cancer. The HOX gene family was initially studied intensively to understand how the expression of each gene was involved in forming axial patterns and shaping the body plan during embryogenesis. More recent investigations have discovered that HOX genes can also play an important role in cancer. The literature has shown that the expression of HOX genes may be increased or decreased in different tumors and that these alterations may differ depending on the specific HOX gene involved and the type of cancer being investigated. New studies are also emerging, showing the critical role of some members of the HOX gene family in tumor progression and variation in clinical response. However, there has been limited systematic evaluation of the various contributions of each member of the HOX gene family in the pathways that drive the common phenotypic changes (or "hallmarks") and that underlie the transformation of normal cells to cancer cells. In this review, we investigate the context of the engagement of HOX gene targets and their downstream pathways in the acquisition of competence of tumor cells to undergo malignant transformation and tumor progression. We also summarize published findings on the involvement of HOX genes in carcinogenesis and use bioinformatics methods to examine how their downstream targets and pathways are involved in each hallmark of the cancer phenotype.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Genes Homeobox/genética , Neoplasias/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Família Multigênica/genética , Fatores de Transcrição/genética
16.
Gynecol Oncol ; 159(1): 229-238, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32694065

RESUMO

OBJECTIVE: To report the frequency of Lynch syndrome (LS) in a cohort of patients from Southeast Brazil bearing endometrial cancer (EC), using a tumor screening universal approach. METHODS: A total of 242 endometrial carcinomas were screened by immunohistochemistry (IHC) and microsatellite instability (MSI) for detection of DNA mismatch repair deficiency (dMMR). MLH1 methylation was assessed to identify sporadic cases. Patients with dMMR tumors were recruited for germline variant analysis by next-generation sequencing of the MLH1, MSH2, MSH6, PMS2, and EPCAM genes. RESULTS: Ninety-three out of 242 tumors (38.5%) were classified as dMMR based on MSI and IHC results. Of these, 54 cases were selected for germline analysis, and 37/54 (68.5%) were available for sequencing. Ten patients (10/37, 27%) harbored germline pathogenic or likely pathogenic variants, most of them in the MSH6 gene (4/10, 40%). Seven variants of uncertain significance were found. Eight novel germline variants were identified. The LS prevalence in our cohort was of at least 4.1%. LS patients presented lower mean age at cancer diagnosis compared with patients diagnosed with sporadic EC. Individuals with dMMR tumors, without germline pathogenic variants detected in LS-genes ("Lynch-like" syndrome), had an intermediate mean age at cancer diagnosis between LS and sporadic cases. CONCLUSION: This is the first report of the LS prevalence in EC screened by a universal approach in Brazil. Our findings contribute to a better understanding of the mutational landscape of this syndrome in Brazil, which is relevant for improved identification, genetic counseling, prevention and control of cancer in LS.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , Neoplasias do Endométrio/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Brasil/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/prevenção & controle , Metilação de DNA , Reparo de Erro de Pareamento de DNA , Análise Mutacional de DNA , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/prevenção & controle , Endométrio/patologia , Feminino , Aconselhamento Genético/organização & administração , Aconselhamento Genético/estatística & dados numéricos , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Imuno-Histoquímica , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Estudos Retrospectivos
17.
Horm Metab Res ; 52(3): 186-193, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32215889

RESUMO

17-Hydroxylase-deficiency (17OHD) is a rare form of congenital adrenal hyperplasia. The aim of the work was to study clinical, biochemical, and the follow up of 17OHD patients and evaluate the function and structure of CYP17A1 mutations. Brazilian patients (three 46, XX and four 46, XY; 17±1.9 years) with combined 17-hydroxylase/17,20-lyase deficiency were evaluated. CYP17A1 gene was sequenced. Functional analysis was performed transfecting COS7 cells, which were exposed to progesterone or 17α-hydroxypregnolone substrates. Hormones were determined by RIA or LC-MS/MS. Three-dimensional structural modeling was performed by Modeller software. All patients presented prepubertal female external genitalia, primary amenorrhea, hypergonadotrophic hypogonadism, hypokalemic hypertension, decreased cortisol, and increased ACTH and corticosterone levels. Five patients presented previously described mutations: p.W406R/p.W406R, IVS2-2A>C/p.P428L, and p.P428L/p.P428L. Two patients presented the compound heterozygous p.G478S/p.I223Nfs*10 mutations, whose CYP17A1 activity and the three dimensional structural modeling are originally studied in this paper. CYP17A1 activity of p.G478S was 13 and 58% against progesterone and 17-hydroxypregnenolone, respectively. The p.I223Nfs*10 caused a truncated inactive protein. Three-dimensional p.G478S structural modeling showed different internal hydrophobic interaction with W313 and created an additional chain side contact with L476 residue. Due to the rarity of 17OHD, the long term follow up (15.3±3.1 years) of our patients will help endocrinologists on the management of patients with 17OHD. The mutation p.G478S/pI223Nfs*10 led to severe 17OHD and impaired CYP17A1 structure and function. The integration of in silico and in vitro analysis showed how the amino acid changes affected the CYP17A1 activity and contributed to clarify the molecular interactions of CYP17A1.


Assuntos
Hiperplasia Suprarrenal Congênita/enzimologia , Esteroide 17-alfa-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/genética , Adulto , Sequência de Aminoácidos , Sequência de Bases , Brasil , Éxons , Feminino , Hormônios/sangue , Humanos , Masculino , Mutação , Esteroide 17-alfa-Hidroxilase/química , Esteroide 17-alfa-Hidroxilase/metabolismo , Adulto Jovem
18.
J Pathol ; 249(1): 102-113, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31038736

RESUMO

Serotonin (5-HT) signaling pathways are thought to be involved in colorectal tumorigenesis (CRT), but the role of 5-HT synthesis in the early steps of this process is presently unknown. In this study, we used carcinogen treatment in the tryptophan hydroxylase 1 knockout (Tph1KO) and transgenic (Tph1fl/fl VillinCre ) mouse models defective in 5-HT synthesis to investigate the early mutagenic events associated with CRT. Our observations of the colonic crypt post-treatment followed a timeline designed to understand how disruption of 5-HT synthesis affects the initial steps leading to CRT. We found Tph1KO mice had decreased development of both allograft tumors and colitis-related CRT. Interestingly, carcinogenic exposure alone induced multiple colon tumors and increased cyclooxygenase-2 (Ptgs2) expression in Tph1KO mice. Deletion of interleukin 6 (Il6) in Tph1KO mice confirmed that inflammation was a part of the process. 5-HT deficiency increased colonic DNA damage but inhibited genetic repair of specific carcinogen-related damage, leading to CRT-related inflammatory reactions and dysplasia. To validate a secondary effect of 5-HT deficiency on another DNA repair pathway, we exposed Tph1KO mice to ionizing radiation and found an increase in DNA damage associated with reduced levels of ataxia telangiectasia and Rad3 related (Atr) gene expression in colonocytes. Restoring 5-HT levels with 5-hydroxytryptophan treatment decreased levels of DNA damage and increased Atr expression. Analysis of Tph1fl/fl VillinCre mice with intestine-specific loss of 5-HT synthesis confirmed that DNA repair was tissue specific. In this study, we report a novel protective role for 5-HT synthesis that promotes DNA repair activity during the early stages of colorectal carcinogenesis. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Transformação Celular Neoplásica/metabolismo , Colo/metabolismo , Neoplasias Colorretais/prevenção & controle , Dano ao DNA , Reparo do DNA , Lesões Pré-Cancerosas/prevenção & controle , Serotonina/biossíntese , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Fator de Transcrição CDX2/genética , Fator de Transcrição CDX2/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Interleucina-6/deficiência , Interleucina-6/genética , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Transdução de Sinais , Fatores de Tempo , Triptofano Hidroxilase/deficiência , Triptofano Hidroxilase/genética
19.
Genet Mol Biol ; 43(4): e20200100, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33001133

RESUMO

Endometrial cancer (EC) harboring heterozygous POLE proofreading inactivating mutations (POLE-exo*) is associated with an increased number of somatic mutations that result in a distinctive anti-tumor immune response. However, the consequences of such POLE mutations in the context of the missing wild-type allele have not yet been described in endometrial tumors. A 72-year-old woman harboring a germline monoallelic frameshift mutation (p.Pro269fsTer26) in POLE was diagnosed with an EC having a somatic heterozygous mutation in the exonuclease domain of POLE (S459F). Targeted gene sequencing revealed an ultramutated phenotype (381 mutations/Mb) in the tumor and a 2-fold excess of mutations on the DNA leading strand. Additionally, we observed a mutational signature similar to the COSMIC signature 10, a higher mutation rate in this tumor than in endometrial tumors with heterozygous POLE-exo*, and an increased number of T lymphocytes. This is the first report of an ultramutated EC harboring a somatic POLE-exo* mutation in association with a germline loss-of-function mutation in this gene. The absence of a wild type POLE allele led to a particularly high mutational burden.

20.
Trop Anim Health Prod ; 52(4): 1971-1976, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31975182

RESUMO

The objective was to evaluate the factors affecting the occurrence of bovine demodecosis from the clinical aspects of injuries, blood profile, and the correlation with weight gain and the season of the year in Sindhi-breed animal management in a tropical environment. Thirty-three Sindhi-breed animals were used: 23 females and 10 males. Clinical examination diagnosed that 90% of the examined animals presented skin lesions characteristic of bovine demodecosis caused by Demodex bovis (P < 0.05). The Sindhi presented a higher fecal parasite egg count and showed a lower body weight gain in the rainy season and a greater weight loss in the drought season (P < 0.05), medium injury predominating, with no effect of sex (P > 0.05). During the drought season, animals clinically infected with bovine demodecosis presented lower red blood cell and platelet counts and total plasma protein, and higher mean corpuscular volume and mean corpuscular hemoglobin concentration, a blood count typical of regenerative macrocytic anemia (P < 0.05). During the rainy season of the year (April to June), the animals showed greater weight gain, but a higher fecal parasite egg count with no effect on the incidence of bovine demodecosis. Infection by gastrointestinal nematodes negatively influenced body weight gain and demodecosis in the animals.


Assuntos
Doenças dos Bovinos/epidemiologia , Infestações por Ácaros/veterinária , Animais , Brasil/epidemiologia , Bovinos/sangue , Doenças dos Bovinos/parasitologia , Feminino , Incidência , Masculino , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/parasitologia , Prevalência , Estações do Ano
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