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1.
Arq. ciências saúde UNIPAR ; 26(2): 159-174, maio-ago. 2022.
Article in Portuguese | LILACS | ID: biblio-1372969

ABSTRACT

A obesidade é definida pelo excesso de gordura corporal acumulada no tecido adiposo quando o indivíduo atinge valores de IMC igual ou superior a 30 Kg/m2. Constitui um dos principais fatores de risco para várias doenças não transmissíveis (DNTs) como por exemplo, diabetes mellitus tipo 2 (DM2), doenças cardiovasculares, hipertensão arterial, acidente vascular cerebral e até mesmo o câncer. Embora a obesidade esteja diretamente relacionada com o consumo calórico excessivo em relação ao gasto energético diário, sua etiologia pode estar associada aos baixos níveis de atividade física, às alterações neuroendócrinas e aos fatores genéticos. Considerando o componente genético, esta pode ser classificada como sindrômicas e estar associada às alterações cromossômicas estruturais ou numéricas, ou como não sindrômica, quando relacionada, principalmente, com os polimorfismos de nucleotídeos simples (SNPs) em alelos que atuam como herança monogênica, ou ainda com a interação vários genes (poligênica multifatorial). Apesar de existirem muitas etiologias diferentes, normalmente a obesidade é tratada a partir da mesma abordagem, desconsiderando a fisiologia que a desencadeou. Dessa forma, o objetivo do presente trabalho foi abordar a obesidade genética não sindrômica por meio a) da descrição breve de perspectiva histórica sobre seu entendimento; b) da exposição dos principais mecanismos moleculares envolvidos com o controle de peso; c) da compilação dos principais genes e SNPs relacionados; d) da definição dos principais genes; e e) da abordagem das principais perspectivas de intervenção.


Obesity is defined as excess body fat accumulated in the adipose tissue when the individual reaches BMI values equal to or greater than 30 kg/m2. It is one of the main risk factors for several non-communicable diseases (NCDs), such as Type 2 Diabetes mellitus (T2D), cardiovascular diseases, high blood pressure, stroke and even cancer. Although obesity is directly related to excessive calorie intake in relation to daily energy expenditure, its etiology may be associated with low levels of physical activity, neuroendocrine changes, and genetic factors. Considering the genetic component, it can be classified as syndromic and be associated with chromosomal or numerical changes, or as non-syndromic and being related mainly to single nucleotide polymorphisms (SNPs) in alleles that act as monogenic inheritance, or with an interaction of several genes (multifactorial polygenic). Although there are many different etiologies, obesity is usually treated using the same approach, disregarding the physiology that triggered it. Thus, the aim of this study was to address non-syndromic genetic obesity through a) a brief description of a historical perspective on its understanding; b) the exposure of the main molecular mechanisms involved in weight control, c) the compilation of the key genes and related SNPs, d) the definition of the key genes and e) the approach of the main intervention representations.


Subject(s)
Humans , Male , Female , Body Weight/genetics , Genes/genetics , Obesity/genetics , Exercise , Body Mass Index , Gene Expression/genetics , Leptin/genetics , Polymorphism, Single Nucleotide/genetics , Receptor, Melanocortin, Type 4/genetics , Diet/methods , Melanocortins/genetics , Receptors, Leptin/genetics , Epigenomics , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolism , Hypothalamus
2.
Article in Chinese | WPRIM | ID: wpr-936230

ABSTRACT

Objective: Transcriptome sequencing and bioinformatics analysis were performed on the gene expression of nasal epithelial cells in patients with seasonal allergic rhinitis (AR) and perennial AR, so as to obtain the differences in the gene expression of nasal epithelial cells between seasonal AR and perennial AR. Methods: The human nasal epithelial cell line(HNEpC) was cultured in vitro, treated with 100 μg/ml mugwort or house dust mite (HDM) extracts for 24 hours. Total cell RNA was extracted, and quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression of cytokines, including IL-6, IL-8, IL-33 and thymic stromal lymphopoietin (TSLP). From November 2019 to November 2020, 3 seasonal AR patients, 3 perennial AR patients, and 3 healthy controls who attended the Department of Otolaryngology Head and Neck Surgery, China-Japan Union Hospital of Jilin University were analyzed. The patients' primary nasal epithelial cells were cultured in vitro, treated with corresponding allergens for 24 hours. Total RNA was extracted for transcriptome sequencing, and the sequencing results were analyzed by bioinformatics. Results: The qPCR results showed that the cytokines IL-6, IL-8, IL-33 and TSLP of HNEpC treated with mugworts extracts and HDM extracts had the same trend of change. After the nasal epithelial cells from patients with seasonal AR and perennial AR were treated with corresponding allergens, there were differences in biological processes and signal pathways between those and control. Gene ontology (GO) enrichment analysis showed that the differentially expressed genes (DEG) in AR patients allergic to mugwort were mainly enriched in the oxidation-reduction process, the negative regulation of apoptosis process, and the cell adhesion; the DEG in AR patients allergic to HDM were mainly enriched in cell adhesion, the negative regulation of cell proliferation and the response to drug. Enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway showed that the DEG of AR patients allergic to mugwort were significantly enriched in arachidonic acid metabolism, p53 signaling pathway and transforming growth factor β (TGF-β) signaling pathway, while the DEG of AR patients allergic to HDM were mainly enriched in cells cycle, Fanconi anemia pathway and DNA replication. Gene Set Enrichment Analysis (GSEA) showed that the inflammatory response, TNF-α/NF-κB signaling pathway and IL-2/STAT5 signaling pathway were significantly up-regulated in AR patients allergic to mugwort, indicating the promotion of inflammatory response; and AR patients allergic to HDM had significant down-regulation of G2M, E2F, and MYC, indicating the inhibition of cell proliferation. The protein-protein interaction network showed that TNF and CDK1 were the most interacting proteins in mugwort and HDM allergic AR patients, respectively. Conclusion: Seasonal AR and perennial AR may affect the different biological processes and signal pathways of nasal epithelial cells, leading to differences in the occurrence and development of AR.


Subject(s)
Allergens , Animals , Computational Biology , Cytokines/metabolism , Epithelial Cells/metabolism , Gene Expression , Humans , Interleukin-33/metabolism , Interleukin-6/metabolism , Interleukin-8 , Nasal Mucosa/metabolism , Plant Extracts/metabolism , Pyroglyphidae , RNA/metabolism , Rhinitis, Allergic/metabolism , Rhinitis, Allergic, Perennial , Rhinitis, Allergic, Seasonal , Seasons
3.
Chinese Journal of Pathology ; (12): 307-313, 2022.
Article in Chinese | WPRIM | ID: wpr-935531

ABSTRACT

Objective: To analyze the genetic landscape of 52 fusion genes in patients with de novo acute lymphoblastic leukemia (ALL) and to investigate the characteristics of other laboratory results. Methods: The fusion gene expression was retrospectively analyzed in the 1 994 patients with de novo ALL diagnosed from September 2016 to December 2020. In addition, their mutational, immunophenotypical and karyotypical profiles were investigated. Results: In the 1 994 patients with ALL, the median age was 12 years (from 15 days to 89 years). In the panel of targeted genes, 15 different types of fusion genes were detected in 884 patients (44.33%) and demonstrated a Power law distribution. The frequency of detectable fusion genes in B-cell ALL was significantly higher than that in T-cell ALL (48.48% vs 18.71%), and fusion genes were almost exclusively expressed in B-cell ALL or T-cell ALL. The number of fusion genes showed peaks at<1 year, 3-5 years and 35-44 years, respectively. More fusion genes were identified in children than in adults. MLL-FG was most frequently seen in infants and TEL-AML1 was most commonly seen in children, while BCR-ABL1 was dominant in adults. The majority of fusion gene mutations involved signaling pathway and the most frequent mutations were observed in NRAS and KRAS genes. The expression of early-stage B-cell antigens varied in B-cell ALL patients. The complex karyotypes were more common in BCR-ABL1 positive patients than others. Conclusion: The distribution of fusion genes in ALL patients differs by ages and cell lineages. It also corresponds to various gene mutations, immunophenotypes, and karyotypes.


Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Gene Expression , Genes, ras , Humans , Infant , Infant, Newborn , Middle Aged , Oncogene Fusion , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Retrospective Studies , Young Adult
4.
Article in Chinese | WPRIM | ID: wpr-928745

ABSTRACT

OBJECTIVE@#To identify the key genes and explore mechanisms in the development of myelodysplastic syndrome (MDS) by bioinformatics analysis.@*METHODS@#Two cohorts profile datasets of MDS were downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed gene (DEG) was screened by GEO2R, functional annotation of DEG was gained from GO database, gene ontology (GO) enrichment analysis was performed via Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and key genes were screened by Matthews correlation coefficient (MCC) based on STRING database.@*RESULTS@#There were 112 DEGs identified, including 85 up-regulated genes and 27 down-regulated genes. GO enrichment analysis showed that biological processes were mainly enriched in immune response, etc, cellular component in cell membrane, etc, and molecular function in protein binding, etc. KEGG signaling pathway analysis showed that main gene enrichment pathways were primary immunodeficiency, hematopoietic cell lineage, B cell receptor signaling pathway, Hippo signaling pathway, and asthma. Three significant modules were screened by Cytoscape software MCODE plug-in, while 10 key node genes (CD19, CD79A, CD79B, EBF1, VPREB1, IRF4, BLNK, RAG1, POU2AF1, IRF8) in protein-protein interaction (PPI) network were screened based on STRING database.@*CONCLUSION@#These screened key genes and signaling pathways are helpful to better understand molecular mechanism of MDS, and provide theoretical basis for clinical targeted therapy.


Subject(s)
Computational Biology , Gene Expression , Gene Expression Profiling , Humans , Microarray Analysis , Myelodysplastic Syndromes/genetics , Protein Interaction Maps
5.
Article in Chinese | WPRIM | ID: wpr-928628

ABSTRACT

OBJECTIVES@#To study the correlation of the expression of Lipin1 in visceral adipose tissue and Lipin2 in liver tissue with hepatic fat content in rats with intrauterine growth retardation (IUGR).@*METHODS@#Pregnant rats were given a low-protein (10% protein) diet during pregnancy to establish a model of IUGR in neonatal rats. The pregnant rats in the control group were given a normal-protein (21% protein) diet during pregnancy. The neonatal rats were weighed and liver tissue was collected on day 1 and at weeks 3, 8, and 12 after birth, and visceral adipose tissue was collected at weeks 3, 8, and 12 after birth. The 3.0T 1H-magnetic resonance spectroscopy was used to measure hepatic fat content at weeks 3, 8, and 12 after birth. Real-time PCR was used to measure mRNA expression levels of Lipin2 in liver tissue and Lipin1 in visceral adipose tissue. Western blot was used to measure protein levels of Lipin2 in liver tissue and Lipin1 in visceral adipose tissue. A Pearson correlation analysis was performed to investigate the correlation of mRNA and protein expression of Lipin with hepatic fat content.@*RESULTS@#The IUGR group had significantly higher mRNA and protein expression levels of Lipin1 in visceral adipose tissue than the control group at weeks 3, 8, and 12 after birth (P<0.05). Compared with the control group, the IUGR group had significantly lower mRNA and protein expression levels of Lipin2 in liver tissue on day 1 after birth and significantly higher mRNA and protein expression levels of Lipin2 at weeks 1, 3, 8, and 12 after birth (P<0.05). At week 3 after birth, there was no significant difference in hepatic fat content between the IUGR and control groups (P>0.05), while at weeks 8 and 12 after birth, the IUGR group had a significantly higher hepatic fat content than the control group (P<0.05). The protein and mRNA expression levels of Lipin1 were positively correlated with hepatic fat content (r=0.628 and 0.521 respectively; P<0.05), and the protein and mRNA expression levels of Lipin2 were also positively correlated with hepatic fat content (r=0.601 and 0.524 respectively; P<0.05).@*CONCLUSIONS@#Upregulation of the mRNA and protein expression levels of Lipin1 in visceral adipose tissue and Lipin2 in liver tissue can increase hepatic fat content in rats with IUGR and may be associated with obesity in adulthood.


Subject(s)
Adult , Animals , Female , Fetal Growth Retardation , Gene Expression , Humans , Liver/metabolism , Organic Chemicals , Pregnancy , RNA, Messenger/metabolism , Rats
6.
Chinese Journal of Biotechnology ; (12): 719-736, 2022.
Article in Chinese | WPRIM | ID: wpr-927739

ABSTRACT

Gluconobacter oxydans are widely used in industrial due to its ability of oxidizing carbohydrate rapidly. However, the limited gene manipulation methods and less of efficient gene editing tools impose restrictions on its application in industrial production. In recent years, the clustered regularly interspaced short palindromic repeats (CRISPR) system has been widely used in genome editing and transcriptional regulation which improves the efficiency of genome editing greatly. Here we constructed a CRISPR/dCpf1-mediated gene transcriptional repression system, the expression of a nuclease inactivation Cpf1 protein (dCpf1) in Gluconobacter oxydans together with a 19 nt direct repeats showed effective repression in gene transcription. This system in single gene repression had strong effect and the relative repression level had been increased to 97.9%. While it could be applied in multiplex gene repression which showed strong repression ability at the same time. Furthermore, this system was used in the metabolic pathway of L-sorbose and the regulatory of respiratory chain. The development of CRISPR transcriptional repression system effectively covered the shortage of current gene regulation methods in G. oxydans and provided an efficient gene manipulation tool for metabolic engineering modification in G. oxydans.


Subject(s)
CRISPR-Cas Systems/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Gene Editing , Gene Expression , Gluconobacter oxydans/genetics , Metabolic Engineering
7.
Braz. j. biol ; 82: e250700, 2022.
Article in English | LILACS, VETINDEX | ID: biblio-1278476

ABSTRACT

Abstract The mutations are genetic changes in the genome sequences and have a significant role in biotechnology, genetics, and molecular biology even to find out the genome sequences of a cell DNA along with the viral RNA sequencing. The mutations are the alterations in DNA that may be natural or spontaneous and induced due to biochemical reactions or radiations which damage cell DNA. There is another cause of mutations which is known as transposons or jumping genes which can change their position in the genome during meiosis or DNA replication. The transposable elements can induce by self in the genome due to cellular and molecular mechanisms including hypermutation which caused the localization of transposable elements to move within the genome. The use of induced mutations for studying the mutagenesis in crop plants is very common as well as a promising method for screening crop plants with new and enhanced traits for the improvement of yield and production. The utilization of insertional mutations through transposons or jumping genes usually generates stable mutant alleles which are mostly tagged for the presence or absence of jumping genes or transposable elements. The transposable elements may be used for the identification of mutated genes in crop plants and even for the stable insertion of transposable elements in mutated crop plants. The guanine nucleotide-binding (GTP) proteins have an important role in inducing tolerance in rice plants to combat abiotic stress conditions.


Resumo Mutações são alterações genéticas nas sequências do genoma e têm papel significativo na biotecnologia, genética e biologia molecular, até mesmo para descobrir as sequências do genoma de um DNA celular junto com o sequenciamento do RNA viral. As mutações são alterações no DNA que podem ser naturais ou espontâneas e induzidas devido a reações bioquímicas ou radiações que danificam o DNA celular. Há outra causa de mutações, conhecida como transposons ou genes saltadores, que podem mudar sua posição no genoma durante a meiose ou a replicação do DNA. Os elementos transponíveis podem induzir por si próprios no genoma devido a mecanismos celulares e moleculares, incluindo hipermutação que causou a localização dos elementos transponíveis para se moverem dentro do genoma. O uso de mutações induzidas para estudar a mutagênese em plantas cultivadas é muito comum, bem como um método promissor para a triagem de plantas cultivadas com características novas e aprimoradas para a melhoria da produtividade e da produção. A utilização de mutações de inserção por meio de transposons ou genes saltadores geralmente gera alelos mutantes estáveis ​​que são marcados quanto à presença ou ausência de genes saltadores ou elementos transponíveis. Os elementos transponíveis podem ser usados ​​para a identificação de genes mutados em plantas de cultivo e até mesmo para a inserção estável de elementos transponíveis em plantas de cultivo mutadas. As proteínas de ligação ao nucleotídeo guanina (GTP) têm papel importante na indução de tolerância em plantas de arroz para combater as condições de estresse abiótico.


Subject(s)
Oryza/genetics , Phenotype , DNA Transposable Elements/genetics , Gene Expression , Guanosine Triphosphate
8.
Neuroscience Bulletin ; (6): 29-46, 2022.
Article in English | WPRIM | ID: wpr-922666

ABSTRACT

A large number of putative risk genes for autism spectrum disorder (ASD) have been reported. The functions of most of these susceptibility genes in developing brains remain unknown, and causal relationships between their variation and autism traits have not been established. The aim of this study was to predict putative risk genes at the whole-genome level based on the analysis of gene co-expression with a group of high-confidence ASD risk genes (hcASDs). The results showed that three gene features - gene size, mRNA abundance, and guanine-cytosine content - affect the genome-wide co-expression profiles of hcASDs. To circumvent the interference of these features in gene co-expression analysis, we developed a method to determine whether a gene is significantly co-expressed with hcASDs by statistically comparing the co-expression profile of this gene with hcASDs to that of this gene with permuted gene sets of feature-matched genes. This method is referred to as "matched-gene co-expression analysis" (MGCA). With MGCA, we demonstrated the convergence in developmental expression profiles of hcASDs and improved the efficacy of risk gene prediction. The results of analysis of two recently-reported ASD candidate genes, CDH11 and CDH9, suggested the involvement of CDH11, but not CDH9, in ASD. Consistent with this prediction, behavioral studies showed that Cdh11-null mice, but not Cdh9-null mice, have multiple autism-like behavioral alterations. This study highlights the power of MGCA in revealing ASD-associated genes and the potential role of CDH11 in ASD.


Subject(s)
Animals , Autism Spectrum Disorder/genetics , Brain , Cadherins/genetics , Gene Expression , Mice , Mice, Knockout
9.
Article in English | WPRIM | ID: wpr-929232

ABSTRACT

Natural products (NPs), especially those from traditional herbal medicines, can evidently modulate human gene expression at multiple levels, leading to a wide diversity of bioactivities. Although numerous bio-functions of NPs for human body have been found, there is little understanding about how NPs achieve it, as less attention was drawn to the definite mechnism by which NPs regulate gene expression. Furthermore, based on the rapidly advancing knowledge of mechanisms for gene regulation in recent years, newly-understood mechanisms, such as post-transcriptional regulation, are found to be involved in NP-elicited bio-effects, providing a new perspective on understanding the role of NPs in gene expression. Therefore, in the current review, we summarize the function of NPs in gene expression from the perspectives of transcriptional, post-transcriptional, and post-translational regulation, which will reinforce the understanding of NP-induced effects in gene expression and facilitate the exploration of more NPs with potential therapeutic effects.


Subject(s)
Biological Products/pharmacology , Gene Expression , Gene Expression Regulation , Humans
10.
Braz. arch. biol. technol ; 65: e22200702, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364476

ABSTRACT

Abstract: Boron is one of the most important micronutrients for plants. Plants may suffer from deficiency or with boron toxicity. Boron plays a role in significant physiological and biochemical events in plants such as synthesis of the cell wall, membrane integrity, antioxidation, transport of photosynthesis products to other organs of the plant. The enzyme activities of ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD) in three different safflower cultivars (Balcı, Dinçer and Remzibey) subjected to different boric acid concentrations (0, 5, 10, 15 mM) were measured spectrophotometrically, and the changes in the expression levels of the genes that encode these enzymes were obtained by quantitative RT-qPCR. When both the spectrophotometric measurements and the mRNA values were evaluated together, both the activity and mRNA values of APX and GR enzymes were found to be the highest in the Dinçer cultivar among the varieties treated with 15 mM boric acid, while the lowest values of these enzymes were determined in the Remzibey cultivar. According to the RT-qPCR results, the lowest SOD and CAT values were determined in Remzibey. The Dinçer cultivar was found to have the highest antioxidant capacity (APX, GR) to cope with oxidative stress caused by boric acid application at high concentrations. The sensitive Remzibey cultivar was found to have the lowest antioxidant capacity to cope with such oxidative stress. Balcı was found to be closer to Dinçer than to Remzibey in terms of boron tolerance. As a result, the boron-sensitive cultivar had low antioxidant activity.


Subject(s)
Trace Elements/administration & dosage , Boron/administration & dosage , Agricultural Cultivation , Carthamus tinctorius/metabolism , Antioxidants/metabolism , Trace Elements/toxicity , Boron/toxicity , Gene Expression/drug effects , Oxidative Stress/drug effects , Carthamus tinctorius/enzymology , Carthamus tinctorius/genetics
11.
Braz. j. biol ; 82: e234855, 2022. tab, graf
Article in English | LILACS | ID: biblio-1153468

ABSTRACT

Abstract Exposure to the hight-fat diet may alter the control of food intake promoting hyperphagia and obesity. The objective of this study was to investigate the effects of this diet on dopamine receptors (drd1 and drd2), proopiomelanocortin (pomc), neuropeptideY (npy) genes expression, and preference food in adult rats. Wistar female rats were fed a hight-fat or control diet during pregnancy and lactation. The offspring were allocated into groups: Lactation - Control (C) and High-fat (H). Post-weaning - Control Control (CC), offspring of mothers C, fed a control diet after weaning; Control Hight-fat (CH), offspring of mothers C, fed a hight-fat diet after weaning; Hight-fat Control (HC), offspring of mothers H, fed with control diet after weaning; and Hight-fat Hight-fat (HH), offspring of mothers H, fed a H diet after weaning. The groups CH and HH presented greater expression of drd1 in comparison to the CC. The drd2 of CH and HC presented higher gene expression than did CC. HH presented higher pomc expression in comparison to the other groups. HC also presented greater expression in comparison to CH. The npy of HH presented greater expression in relation to CH and HC. HH and HC have had a higher preference for a high-fat diet at 102º life's day. The high-fat diet altered the gene expression of the drd1, drd2, pomc and npy, and influencing the food preference for high-fat diet.


Resumo A exposição à dieta hiperlipídica pode alterar o controle da ingestão de alimentos, promovendo hiperfagia e obesidade. O objetivo deste estudo foi investigar os efeitos dessa dieta sobre a expressão gênica dos receptores de dopamina (drd1 e drd2), da proopiomelanocortina (pomc) e neuropeptídeo Y (npy), e preferência alimentar em ratos adultos. Ratas Wistar foram alimentadas com uma dieta hiperlipídica ou controle durante a gestação e lactação. Os descendentes foram alocados em grupos: Lactação - Controle (C) e Hiperlipídica (H). Pós-desmame - Controle Controle (CC), descendentes das genitoras do grupo controle e alimentados com dieta controle após o desmame; Controle Hiperlipídica (CH), descendentes das genitoras do grupo controle e alimentados com dieta hiperlipídica após o desmame; Hiperlipídica Controle (HC), descendentes das genitoras do grupo hiperlipídica e alimentados com dieta controle após o desmame; Hiperlipídica Hiperlipídica (HH), descendentes das genitoras do grupo hiperlipídica e alimentados com dieta hiperlipídica após o desmame. Os grupos CH e HH apresentaram maior expressão de drd1 em comparação ao CC. O drd2 de CH e HC apresentou maior expressão gênica que o CC. HH apresentou maior expressão de pomc em comparação com os outros grupos. O HC também apresentou maior expressão de pomc em comparação ao CH. O npy do HH apresentou maior expressão em relação ao CH e HC. HH e HC tiveram uma preferência maior por uma dieta rica em gordura no 102º dia de vida. A dieta hiperlipídica alterou a expressão gênica dos drd1, drd2, pomc e npy e influenciou na preferência alimentar pela dieta hiperlipídica.


Subject(s)
Animals , Female , Pregnancy , Rats , Pro-Opiomelanocortin/genetics , Diet, High-Fat/adverse effects , Body Weight , Neuropeptide Y/genetics , Gene Expression , Receptors, Dopamine/genetics , Rats, Wistar , Food Preferences
12.
São Paulo; s.n; 2022. 59 p.
Thesis in Portuguese | LILACS, Inca | ID: biblio-1367281

ABSTRACT

Introdução: O carcinoma endometrial (CE) foi classificado pelo sistema de Bokhman em tipos I e II com base em observações clínicas e epidemiológicas. O tipo I corresponde aos tumores de baixo grau e o tipo II aos tumores de alto grau. Adicionalmente, estudos recentes propuseram que a classificação também fosse baseada em aspectos histológicos e moleculares com base nos dados do TCGA (The Cancer Genome Atlas). Foram identificados quatro grupos moleculares distintos de CE: (1) com mutações no POLE (fenótipo "ultramutado"), (2) "alto número de cópias" (mutações em TP53), (3) !baixo número de cópias" (em que os tumores não apresentam nenhuma das alterações descritas nos outros tipos) e (4) tumores com predomínio de instabilidade de microssatélites. A imunohistoquímica (IHC) para proteínas do gene de reparo é usada para identificar a deficiência de genes de reparo do DNA (Mismatch Repair ­ MMR) associada à instabilidade de microssatélites(MSI). A coloração nuclear positiva representa a expressão retida de proteínas MMR, enquanto a perda completa representa deficiência de MMR. O padrão de expressão heterogênea (HEP), ou seja, concomitância em um mesmo espécime de áreas positivas e totalmente negativas tem sido observada em CE. No presente momento, as principais diretrizes determinam que a presença de HEP seja interpretada como expressão retida de proteínas MMR. Não há, porém, consenso quanto à classificação e interpretação de HEP, nem conhecimento do impacto da classificação de HEP como subtipo molecular diferente em relação às características clínicas e prognósticas. Objetivos: realizar a classificação molecular dos casos de CE com HEP das proteínas relacionadas aos genes de reparo do DNA e comparação do perfil molecular entre áreas positivas e negativas no estudo imunohistoquímico. Materiais e Métodos: De janeiro/2007 a dezembro/2017 foram identificados 356 casos de CE, 16 deles com HEP. A classificação molecular foi feita com base no protocolo PROMISE para CE. Cada área (expressão retida ou perdida) foi macrodissecada e o status molecular foi avaliado separadamente quanto ao status MSI (Idylla), metilação do promotor MLH1 (NGS - ponto de corte para positividade ≥ 15%), status POLE (NGS) e status p53 (IHC). Variáveis clínicas e patológicas também foram avaliadas e correlacionadas com cada caso. Resultados: A histologia endometrioide foi predominante (15 casos), bem como ausência de invasão linfovascular (11 casos), ausência de padrão MELF (10 casos), graus FIGO 1 e 2 (13 casos), invasão miometrial < 50% (13 casos) e estadiamento T1 (13 casos). Todos os pacientes estavam vivos e sem evidência de doença no último acompanhamento, exceto por um caso, cujo status de sobrevida era desconhecido. Dois casos que seriam descritos como apresentando expressão retida de proteínas relacionadas a genes de reparo do DNA por IHC apresentaram-se na análise molecular com instabilidade de microssatélites(MSI-H). Nos casos de HEP, a proteína MSH6 foi a maisfrequentemente envolvida (9 casos, 7 isolados). A proteína MLH1 apresentou-se alterada em 6 casos, sendo a única proteína associada a co-alterações (com MSH6 e PMS2). Seis casos apresentaram-se metilados por MLH1, padrão encontrado tanto em áreas com perda quanto em áreas com retenção das proteínas relacionadas a MMR por IHC e dois casos apresentaram metilação em apenas uma das áreas. Em relação ao status de POLE, 6 casos apresentaram mutação, 2 com mutações tanto em áreas com perda quanto em áreas com retenção de expressão, 3 apenas na área com perda e 1 apenas na área com retenção. Dois casos apresentam padrão aberrante de p53 (MSH6 alterados) em ambas as áreas. Conclusão: em pacientes portadoras CE e com tumores apresentando HEP a correlação entre a IHC e os achados moleculares é heterogênea e o diagnóstico entre casos com retenção ou das proteínas relacionadas a MMR não é factível apenas com realização de IHC. A análise molecular deve ser realizada em todos os casos de CE com HEP para determinar adequadamente as característicasintrínsecas de cada tumor. Devido à raridade desse achado, esta proposta é financeiramente viável e tem o potencial de mudar a prática clínica em um subconjunto de pacientes, permitindo tratamentos inovadores. HEP deve ser relatado como um padrão distinto e não considerado como uma expressão sinônimo de expressão retida de proteínas MMR em CE.


Introduction: Endometrial adenocarcinoma is classified by the Bokhman system in type I and II based on clinical and epidemiological observations, whereas the type I represents low grade tumors and type II high grade tumors. Additionally, a classification based on histological aspects and molecular profile has been proposed. The TCGA (The Cancer Genome Atlas) identified four molecular groups of endometrial adenocarcinomas: (1) mutations in POLE ("ultramutated" phenotype), (2) "high copy number" (mutations in TP53), (3) "low number of copies " (in which the tumors do not exhibit any of the changes described in the other types) and (4) tumors with predominance of microsatellite instability. In a small number of patients, heterogeneous staining is observed in the evaluation protein expression for mismatch repair genes. Objectives: to evaluate and perform the molecular classifications of cases of endometrial carcinoma with heterogeneous staining by IHC of proteins related to mismatch repair genes and comparison of the molecular profile of positive and negative areas in the IHC study. Cases and Methods: From January/2007 to December/2017 354 cases with EC were identified, 16 of those with HEP. Molecular classification was made based on the PROMISE protocol for EC. Each area (retained and lost expression) was macrodissected and molecular status was evaluated separately regarding MSI status (Idylla), MLH1 promoter methylation (NGS - cutoff for positivity ≥ 15%), POLE status (NGS) and p53 status (IHC). Clinical and pathologic variables were also evaluated and correlated with each case. Results: Endometrioid histology was predominant (15 cases), as absent lymphovascular invasion (11 cases), absence of MELF pattern (10 cases), FIGO Grade 1 and 2 (13 cases), and T1 stage (13 cases). All patients were alive and disease-free at the last follow-up. Two cases that would be described as retained by IHC presented in the molecular analysis as MSI-H. In HEP cases MSH6 was more frequent (9 cases, 7 isolated). MLH1 was altered in 6 cases, and wasthe only protein associated with co-alterations (with MSH6 and PMS2). Six cases were MLH1 methylated, found both in lost and retained areas. As POLE status, there were 6 mutated cases, 2 of those with mutations both in lost and retained areas, and 3 the lost area. Two cases had p53 aberrant pattern (MSH6 altered), that was seen both in the retained and in the lost areas. Conclusion: Correlation between IHC and molecular findings is heterogeneous, and determination between retained or lost expression of MMR proteins by IHC when HEP occurs, however feasible, does not represent the actual molecular alterations. Thus, molecular analysis should be performed every case to adequately determine the intrinsic features of each tumor. Due to the rarity of this finding, this is financially viable and has the potential to change clinical practice in a subset of patients. HEP should be reported as a distinct pattern, and not considered as a synonym expression of retained expression of MMR proteins in EC.


Subject(s)
Humans , Female , Adenocarcinoma/genetics , Gene Expression/genetics , Endometrial Neoplasms/genetics , DNA Repair/genetics , Immunohistochemistry , Retrospective Studies
13.
Braz. J. Pharm. Sci. (Online) ; 58: e19922, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384022

ABSTRACT

Angiotensin-II (AgII) is thought to be crucial for tumor growth and progression. Moreover, hydrogen sulfide (H2S) performs a controversial action in cancer pathology. Zofenopril (ZF) is an angiotensin-converting enzyme (ACE) inhibitor with H2S donating properties. Hence, this study aims at investigating the tumor suppressor activity of ZF and elucidating the involved trajectories in Ehrlich's solid tumor (EST)-bearing mice. EST was induced by the intradermal injection of Ehrlich's ascites carcinoma cells into femoral region. All parameters were assessed after 28 days post-inoculation or one-week thereafter. ZF treatment resulted in significant reduction of tumor weights with marked decrease in IL-6 and VEGF levels in serum, and tumor Ag II and CEA contents. Additionally, the administration of ZF downregulated the tumor gene expression of cyclin-D, ACE-1, and Bcl2 and upregulated the proapoptotic gene, BAX. Moreover, ZF increased CBS gene expression, which is a major contributor to cellular H2S production. In addition, ZF was able to reduce the protein expression of PI3K, pAKT, pGSK-3ß, and NFκB. Our study has provided novel insights into the possible mechanisms by which ZF may produce its tumor defeating properties. These intersecting trajectories involve the interference between PI3K/Akt and CBS signaling pathways


Subject(s)
Animals , Male , Mice , Carcinoma, Ehrlich Tumor/pathology , Neoplasms , Angiotensin II/adverse effects , Carcinoma/pathology , Gene Expression , Vascular Endothelial Growth Factor A
14.
Braz. J. Pharm. Sci. (Online) ; 58: e19332, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384002

ABSTRACT

Chronic lymphocytic leukemia (CLL) is a blood cancer characterized by the accumulation of clonal B-lymphocytes. This study evaluated the mRNA gene expression of miR-15a, miR-16- 1, ZAP-70, and Ang-2 by qPCR, as well as the plasma levels of Bcl-2 by Elisa immunoassay, in CLL patients and healthy controls. Significant differences were observed when comparing patients and controls regarding miR-15a (p < 0.001), miR-16-1 (p < 0.001) mRNA, Ang-2 gene expression, and Bcl-2 plasma levels (p < 0.001). When stratified by risk, differences were maintained with a significantly reduced expression in high-risk patients. A positive correlation was observed between miR-15a and platelets (R2 = 0.340; p = 0.009) as well as between Bcl-2 and leukocytes (R2 = 0.310; p = 0.019). Conversely, negative correlations were observed between ZAP-70 and platelets (R2 = - 0.334; p = 0.011), between miR-15a and lymphocytes (R2 = - 0.376; p = 0.004), as well as between miR-16-and lymphocytes (R2 = - 0.515; p = 0.00004). The data suggest that a reduction in miR-15a and miR-16-1 expressions, in addition to an overexpression of Bcl-2, are associated with the reduction in apoptosis and, consequently, to a longer survival of lymphocytes, thus contributing to lymphocyte accumulation and aggravation of the disease. By contrast, Ang-2 expression was significantly higher in A than in B + C Binet groups. This context leads to the speculation that this biomarker should be investigated in more robust studies within populations with a still relevantly indolent form of the disease in an attempt to identify those patients with a greater potential for an aggravation of the disease


Subject(s)
Humans , Male , Female , Biomarkers/analysis , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , ZAP-70 Protein-Tyrosine Kinase/analysis , Patients , Enzyme-Linked Immunosorbent Assay/instrumentation , Gene Expression , Apoptosis
15.
São Paulo; s.n; s.n; 2022. 77 p. graf, tab.
Thesis in Portuguese | LILACS | ID: biblio-1379350

ABSTRACT

A bactéria Gram-negativa Pseudomonas aeruginosa é um patógeno oportunista frequentemente associado a vítimas de queimaduras graves ou indivíduos com fibrose cística, sendo os isolados resistentes a carbepenêmicos dessa espécie considerados pela OMS como uma das maiores ameaças ao controle de infecções. O estabelecimento da infecção por esse patógeno é dependente de uma série de fatores de virulência, entre eles o pilus tipo IV (T4P), que possui papel importante na adesão a superfícies e motilidade do tipo twitching, essenciais para a colonização do hospedeiro. Uma das moléculas importantes na diferenciação entre as formas séssil e planctônica de P. aeruginosa é o segundo mensageiro bis-(3,5)-di-guanosina monofosfato cíclico (c-di-GMP), cuja síntese é feita enzimaticamente por diguanilato ciclases (DGCs). DgcP é uma DGC localizada nos polos da célula, que tem sua atividade de síntese de c-di-GMP aumentada na presença da proteína FimV, essencial para a montagem do T4P em P. aeruginosa. Neste trabalho, ensaios de microscopia de fluorescência, organização e expressão gênica foram realizados com o objetivo de aumentar a compreensão sobre o papel de DgcP em relação a sua expressão e aos fatores que regulam o T4P de P. aeruginosa. A proteína DgcP em fusão com mNeonGreen no C-terminal, expressa a partir do locus cromossômico, se localiza de maneira predominantemente bipolar tanto na linhagem selvagem quanto nos mutantes ΔpilA, ΔpilR e ΔchpA, evidenciando que seu padrão de localização não depende dos sistemas de regulação Pil-Chp e PilS-PilR. Ensaios de RT-PCRmostraram que dgcP se encontra em operon com PA14_72430 e dsbA1, indicando um papel celular conjunto entre esses genes, até o momento, desconhecido. Por fim, ensaios de qRT-PCR revelaram que os níveis de mRNA de dgcP são invariáveis nas linhagens WT, ΔpilA, ΔpilR, ΔchpA e ΔfimV, cultivadas em meio líquido ou meio sólido. Os resultados aqui mostrados, combinados com trabalhos prévios do nosso e de outros grupos, sugerem que DgcP é uma diguanilato ciclase responsável por geração constante de c-di-GMP nos polos da célula, possivelmente, atuando na sinalização local dependente do dinucleotídeo cíclico, cuja localização e atividade não são dependentes dos sistemas de regulação que atuam sobre o T4P


The Gram-negative bacterium Pseudomonas aeruginosa is an opportunistic pathogen often associated with severe burn victims or individuals with cystic fibrosis, which carbapenem-resistant isolates were classified by th World Health Organization classified one of the greatest threats to infection control. The establishment of infection by this pathogen is dependent on a series of virulence factors, including the type IV pilus (T4P), which plays an important role in adhesion to surfaces and twitching motility, essential features for host colonization. Bis-(3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) is a second messenger that involved in processes of biofilm formation, motility, and virulence. The diguanylate cyclase DgcP synthetizes cdi-GMP and it is located at the cell poles, and its activity depends on the scaffold protein FimV, essential for T4P assembly in P. aeruginosa. By increasing c-di-GMP levels, DgcP decreases flagellum-dependent motility and increases biofilm formation. In this work, fluorescence microscopy, gene organization and expression assays were performed to understand the whether DgcP localization and expression are under the control of T4P regulatory proteins. Fluorescence microscopy analysis showed that DgcP localizes predominantly at both cell poles in ΔpilA, ΔpilR, and ΔchpA mutants, showing that its localization pattern does not depend on the Pil-Chp and PilS-PilR systems. Furthermore, RT-PCR assays showed that dgcP is found in an operon with PA14_72430 and dsbA1, indicating an unknown putative related cellular role for these genes. Finally, qRT-PCR assays indicated that DgcP expression is invariant in ΔpilA, ΔpilR, ΔchpA, and ΔfimV mutants, either in liquid or solid medium. The results shownhere, combined with previous work by ours and other groups, suggest that DgcP is a diguanylate cyclase responsible for constant generation of c-di-GMP at the cell poles, possibly acting in local signaling dependent on the cyclic dinucleotide, but that is not under the control of the known T4P regulatory systems


Subject(s)
Operon , Pseudomonas aeruginosa/classification , Infection Control/instrumentation , World Health Organization , Burns , Gene Expression/genetics , Cells , Virulence Factors/adverse effects , Infections/complications , Microscopy, Fluorescence/methods
16.
São Paulo; s.n; s.n; 2022. 106 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1380458

ABSTRACT

Fruit ripening is a biochemical process that results in flavor, odor, texture, and color suitable for human consumption, in addition to providing access to important nutrients. Although ripening promotes sensory and nutritional increases in fruits, there is also an increased susceptibility to physical damage, as is the case with papaya. These transformations occur due to changes in gene expression patterns at different stages of maturity, whose control and coordination result from the combined action of plant hormones, especially ethylene. As the action of this hormone in the regulation of gene expression is still elusive, this dissertation sought to address the global analysis of the transcriptome in an overview study of molecular processes involved in the ripening of ethylene-treated and non-treated papaya. Transcription factors related to ethylene synthesis and signaling had increased activity towards exogenous-ethylene treatment. Consequently, ethylene-induced enzymes had their coding genes differentially expressed, like genes related to the synthesis of carotenoids, linalool, and vitamins, which increase color, aroma, and antioxidant activity, respectively. Metabolic pathways related to the synthesis of sugars were suppressed while genes encoding the enzyme responsible for sucrose synthesis maintained a basal expression, showing that the accumulation of sugars occurs before the ripening process. The firmness of the peel and pulp of the fruits were strongly influenced by the treatment with ethylene and by the time of the experiment, suffering the action of numerous enzymes related to the degradation of the cell wall. The main enzyme responsible for softening the pulp was polygalacturonase, together with the activity of other pectinases and cellulases. In contrast to the need for the pre-climacteric action of pectate lyase and pectinesterase reported in other fleshy fruits, such as tomatoes and strawberries, papaya did not show a significant difference in their expression. The meta-analysis of several papaya ripening transcriptomes confirmed the expression profile observed in the previous RNA-seq, besides providing statistical enrichment to the biological narratives. Finally, the present study gathered a range of robust information on the gene regulation of the papaya ripening process, which opens possibilities for future approaches to transcriptomic analysis and validates the use of papaya as a model for such studies


O amadurecimento de frutos é um processo bioquímico que resulta em sabor, odor, textura e cor adequados para o consumo humano, além de propiciar o acesso a nutrientes importantes. Apesar do amadurecimento promover incrementos sensoriais e nutricionais nos frutos, ocorre também um aumento da suscetibilidade a danos físicos, como é o caso do mamão. Essas transformações ocorrem devido às alterações nos padrões de expressão gênica nos diferentes estádios de amadurecimento, cujo controle e coordenação decorrem da ação combinada de hormônios vegetais, principalmente do etileno. Como a ação deste hormônio na regulação da expressão gênica ainda é elusiva, a presente dissertação buscou abordar a análise global do transcriptoma em um amplo estudo dos processos moleculares envolvidos no amadurecimento de mamões tratados e não tratados com etileno. Os fatores de transcrição relacionados com a síntese e a sinalização do etileno tiveram sua atividade aumentada perante o tratamento exógeno com etileno. Consequentemente, as enzimas reguladas por esse hormônio tiveram seus genes de codificação expressos diferencialmente, como foi o caso de genes relacionados à síntese de carotenoides, linalool e vitaminas, que atuam no aumento da cor, aroma e atividade antioxidante, respectivamente. Vias metabólicas relacionadas com à síntese de açúcares foram reprimidas enquanto genes codificantes da enzima responsável pela síntese de sacarose mantiveram uma expressão basal, evidenciando que o acúmulo de açúcares ocorre antes do processo de amadurecimento. A firmeza da casca e da polpa dos frutos foram fortemente influenciadas pelo tratamento com etileno e pelo tempo de experimento, sofrendo ação de inúmeras enzimas relacionadas com a degradação da parede celular. A principal enzima responsável pelo amolecimento da polpa foi a poligalacturonase, em conjunto com a atividade de outras pectinases e celulases. Em contraste com a necessidade da ação pré-climatérica da pectato liase e da pectinesterase relatada em outras frutas carnosas, como tomates e morangos, o mamão não apresentou uma diferença significativa na expressão das mesmas. A meta-análise de diversos transcriptomas do amadurecimento do mamão reafirmaram o perfil de expressão observado no RNA-seq, além de prover enriquecimento estatístico às narrativas biológicas. Por fim, o presente estudo reuniu uma gama de informações robustas sobre a regulação gênica do processo de amadurecimento do mamão papaia, o que abrange a possibilidade para futuras abordagens de análise transcriptomica e valida o uso do mamão como modelo para tais estudos


Subject(s)
Carica/anatomy & histology , Systems Biology/instrumentation , Ethylenes/adverse effects , Sucrose , Climacteric , Gene Expression , Lycopersicon esculentum , Transcriptome/genetics , Fruit , Antioxidants/analysis
17.
São Paulo; s.n; s.n; 2022. 157 p. tab, graf, ilus.
Thesis in English | LILACS | ID: biblio-1380998

ABSTRACT

Melanoma accounts for 3% of skin neoplasms and is the leading cause of death from skin disorders worldwide. The high mortality rate associated with this disease stems from the high capacity of melanoma patients to develop metastases and treatment relapse with inhibitors of the MAPK signaling pathway (such as BRAF inhibitors), commonly used in melanoma therapy. Thus, the investigation of genes involved in the mechanisms of melanoma development is essential for new and more effective therapeutic strategies. Hence, we describe in this thesis two projects involving the genes SIN3B and IRF4 as possible biomarkers for cutaneous melanoma. Initially, through bioinformatics analyses performed by our group, an upregulation of SIN3B was found in metastatic melanomas. This result together with the understanding of SIN3B role in regulating gene expression and oncogenic transformation, prompted us to describe in this thesis some mechanisms by which SIN3B may influence melanoma development. We then sought to characterize the gene function using SIN3B-deleted cells, generated by the CRISPR-Cas9 methodology. Initially, we observed increased SIN3B expression in BRAF-mutant metastatic melanomas, where we noted that the long splicing variant of the gene (NM_001297595.1) was effectively prevalent in melanomas. Subsequently, we designed gRNAs between the exons 2 and 3 of the human SIN3B gene and engineered three knockout clones and three control clones (containing empty lentiCRISPRv2 plasmid) from different melanoma cell lines (SKMEL28, A2058, and A375). Through functional analyses, it was observed that the absence of the gene did not interfere in the proliferation of tumor cells; however, it led to a decrease in invasive properties. These results were verified by Boyden chamber assays and transcriptome analysis (total RNA sequencing of deleted cells), where a decrease in migration and motility pathways was observed. Additionally, a screening of synthetically lethal genes with SIN3B was performed with a genome wide CRISPR library. These results showed that USP7 and STK11 genes, which belong to the FoxO signaling pathway, were essential in SIN3B-depleted melanoma cells. Finally, through a collaborative project with the Wellcome Trust Sanger Institute, previous large-scale sequencing analyses demonstrated that deletion of the IRF4 gene was lethal for melanoma cells. Accordingly, we performed IRF4 silencing in vitro and noticed that the lack of IRF4 promotes cell death and apoptosis, independently of MYC and MITF, known in the literature to be downstream targets of this gene. Therefore, these data suggest that IRF4 plays a vital role in melanoma cell survival. Taken together, both works herein described in this thesis demonstrate how CRISPR-Cas9 can be applied to study the functions and mechanisms of genes involved in melanoma progression, collectively helping in the development of more effective therapeutic strategies for this tumor


O melanoma representa 3% dos tipos de neoplasias cutâneas e é a maior causa das mortes por distúrbios de pele no mundo. A alta taxa de mortalidade associada à essa doença advém da alta capacidade de pacientes com melanoma desenvolverem metástases, e apresentarem recidiva após tratamento com inibidores da via de sinalização MAPK (como da proteína BRAF), comumente utilizados no tratamento de pacientes metastáticos. Assim, a investigação de genes envolvidos nos mecanismos de desenvolvimento do melanoma é primordial para novas estratégias terapêuticas mais efetivas. Dessa forma, descrevemos no presente trabalho dois projetos envolvendo os genes SIN3B e IRF4 como possíveis biomarcadores para melanoma cutâneo. Em análises prévias de bioinformática realizados pelo nosso grupo, SIN3B foi identificado tendo maior expressão em melanomas metastáticos. Além disso, diversos estudos mostraram que o gene está envolvido na regulação da expressão gênica e transformação oncogênica. Dessa forma, descrevemos nessa tese alguns mecanismos pelos quais SIN3B pode influenciar no desenvolvimento do melanoma, através da caracterização funcional de células SIN3B-deletadas pela metodologia CRISPR-Cas9. Inicialmente, observamos aumento na expressão de SIN3B em melanomas metastáticos BRAF-mutados, onde notamos que a variante de splicing longa do gene (NM_001297595.1), era efetivamente prevalente em melanomas. Assim, desenhamos sequências de RNA guias entre os éxons 2 e 3 do gene SIN3B humano e, obtivemos três clones knockout e outros três clones controle (contendo plasmídeo vazio) em diferentes linhagens de melanoma (SKMEL28, A2058 e A375), para caracterização funcional. Observou-se que a ausência do gene não interferiu na proliferação das células tumorais, contudo, acarretou na diminuição de processos invasivos. Esses resultados foram averiguados através de ensaios em câmara de Boyden e análises de transcriptoma (sequenciamento de RNA total das células deletadas), onde notou-se diminuição das vias de migração e motilidade. Adicionalmente, um rastreamento de genes sinteticamente letais com SIN3B foi realizado com uma biblioteca de CRISPR capaz de silenciar todo o genoma. Esses resultados mostraram que os genes USP7 e STK11, ambos pertencentes à via de sinalização de FoxO, são essenciais nas células SIN3B deletadas. Por fim, através de um projeto colaborativo com o Wellcome Trust Sanger Institute, análises prévias de sequenciamento de larga escala demonstraram que a deleção do gene IRF4 era letal para células de melanoma. Dessa forma, realizamos o silenciamento de IRF4 in vitro e notamos que a ausência do gene promove morte celular e apoptose, independentemente de MYC e MITF, conhecidos na literatura por serem alvos downstream do gene. Portanto, esses dados sugerem que IRF4 tem um papel importante na sobrevivência de células de melanoma. Em conjunto, ambos trabalhos descritos nessa tese, demonstram como a metodologia CRISPR-Cas9 pode auxiliar no entendimento de processos importantes para a malignidade do melanoma e contribuir para estratégias terapêuticas mais efetivas para esse tumor


Subject(s)
Skin Neoplasms/complications , Methodology as a Subject , Melanoma/pathology , Neoplasm Metastasis , Neoplasms , Patients/classification , Skin , In Vitro Techniques/methods , Biomarkers/analysis , Gene Expression , Cell Survival , Sequence Analysis, RNA/instrumentation , Computational Biology/methods , Absenteeism , Clustered Regularly Interspaced Short Palindromic Repeats
18.
São Paulo; s.n; s.n; 2022. 130 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1396955

ABSTRACT

O câncer colorretal (CCR) é o terceiro câncer mais diagnosticado em humanos. O CCR causou mais de 900.000 mortes em 2020 e foi estimado, para o período entre 2020 - 2025, um incremento de 13.5 % no número de casos novos de acordo com a plataforma Web Global Cancer Observatory. A Terapia Fotodinâmica (PDT) é uma alternativa terapêutica promissora. Conhecer as vias de sinalização de morte celular, assim como, as respostas associadas com a resistência ao dano foto-oxidativo, são relevantes para incrementar a eficiência da PDT. Neste trabalho, investigamos como as células de adenocarcinoma colorretal HT 29 respondem ao dano fotoinduzido gerado pelo fotossensibilizador (FS) meso-tetrafenilporfirina dissulfônado (TPPS2a), uma molécula que é ativada pela irradiação com luz em 522 nm. Como esperado, após irradiação (2.1 J cm-2) foi verificado que com o incremento do TPPS2a houve diminuição da viabilidade celular. A concentração do FS escolhida para darmos seguimento ao estudo foi a necessária para reduzir em 30 % a sobrevida celular (DL30; 148 nM). Abordagens moleculares nos permitiram identificar que nas células fotossensibilizadas a redução na maturação da catepsina D (CTSD, 55 %) e da catepsina B (CTSB, 52 %) contribuem com a disfunção endolisossomal. Além disso, comprovamos que as células fotossensibilizadas tiveram, pela menor quantidade de CTSD ativa, o processamento da prosaposina (PSAP) significativamente afetado. Células coletadas após 24 horas de irradiação expressaram 7 vezes mais PSAP do que as amostras dos grupos controle, sugerindo que as reações de oxidação causadas pelo TPPS2a podem ocasionar o acúmulo de glicoesfingolipídios nos endossomos e nos lisossomos, mimetizando o fenótipo observado em doenças de armazenamento lisossomal. Imagens de células HT 29 com expressão estável da proteína LGALS3 fusionada ao marcador EFGP mostraram que, após 24 horas de irradiação, as células não ativaram a lisofagia para remover os endossomos e os lisossomos danificados. A ausência do recrutamento da LGALS3 também apontou que as membranas dos endossomos e dos lisossomos não apresentam rupturas permanentes que permitam a passagem de uma molécula de 26 kDa. Experimentos complementares de análise da expressão proteica dos marcadores autofágicos LC3-II e p62/SQSTM1 (referida como p62) confirmaram o bloqueio do fluxo autofágico nas células fotosenssibilizadas. Pelo envolvimento do sistema endolisossomal no tráfego de membranas e no fluxo de lipídios, o aumento da transcrição da Hidroximetilglutaril-CoA reductase (HMGCR) (≈ 1.6 vezes) uma enzima envolvida na síntese de novo do colesterol - sugeriu que a disfunção dos endossomos e dos lisossomos altera a distribuição de colesterol. Não obstante, para manter a homeostase lipídica nas células fotossensibilizadas este não foi o único mecanismocompensatório acionado, uma vez que houve um incremento sutil; porém, significativo (1.2 vezes) na transcrição da ceramidase ácida (ASAH1). Em conjunto, nossos dados apontam que a fotossensibilização com TPPS2a constitui uma ferramenta promissora para causar dano no sistema endolisossomal, inibindo a autofagia e permitindo o estudo das respostas metabólicas em células expostas a estresse oxidativo


Colorectal cancer (CRC) is the third most commonly diagnosed cancer in humans. CRC caused more than 900,000 deaths in 2020 and it was estimated for the period 2020 - 2025, an increase of 13.5 % in the number of new cases according to the Global Cancer Observatory Web platform. Photodynamic Therapy (PDT) is a promising therapeutic alternative. Understandings of cell death signaling pathways as well as the adaptive responses associated with resistance to photo-oxidative damage are relevant to optimize the effectiveness of PDT. For this purpose, in this research, we investigated how HT-29 colorectal adenocarcinoma cells respond to photosensitization reactions generated by TPPS2a, a molecule activated by irradiation with light at 522 nm. PS concentrations displayed increased inhibitory effect on cell viability after irradiation (2.1 J cm-2). The lethal dose selected to photosensibilize cells was the TPPS2a concentration able to reduce 30 % of cell survival (LD30; 148 nM). By molecular methods, we observed a reduction in cathepsin D (CTSD, 55 %) and cathepsin B (CTSB, 52 %) maturation, depletion that may contribute to endo-lysosomal dysfunction in photosensitized cells. It is widely known that endo-lysosomal cathepsins are crucial in protein turnover and degradation. Thus, we focused on the consequence of CTSD reduction. Literature data indicate that CTSD plays a key role in prosaposin (PSAP) processing to the four saposins (SAPs) that are required in glycosphingolipids breakdown. In fact, our results in photosensitized cells showed that, due to the lower amount of active CTSD, PSAP processing was significantly affected. Cells collected after irradiation expressed 7 times more PSAP than cells from the control groups. This data suggest that oxidative photodamage induced by TPPS2a may result in glycosphingolipid-accumulating endosomes and lysosomes, phenotype which mimics lysosomal storage diseases. Furthermore, we monitored by fluorescence microscopy a form of selective autophagy which detects and removes damaged endosomes and lysosomes known as lysophagy. Images of HT-29 cells expressing Galectin 3/LGALS3 fused to EFGP showed that photosensitized cells did not activate lysophagy. The absence of LGALS3 recruitment also indicated that the membranes of endosomes and lysosomes do not present ruptures which allow the passage of proteins with a molecular weight up to at least 26 kDa. Protein expression analysis of the autophagic markers LC3-II and p62/SQSTM1 (referred as p62) confirmed autophagic flux blockade in cells challenged with photoactivated TPPS2a. The endo-lysosomal system plays a key role in membrane trafficking and lipid flux. At the transcriptional level, 1.6-fold increase in gene expression of Hydroxymethylglutaryl-CoA reductase (HMGCR) - an enzyme involved in the synthesis de novo of cholesterol - indicated that endosomes and lysosomes dysfunction alters the distribution of cholesterol in cellschallenged with photoactivated TPPS2a. However, to maintain lipid homeostasis in photosensitized cells, this was not the only compensatory mechanism triggered, since there was a slightly increase (1.2-fold) in the transcription of acid ceramidase (ASAH1). Taken together, our data showed that photosensitization with TPPS2a constitutes a promising tool to damage the endolysosomal system, to inhibit autophagy and to study metabolic responses in cells exposed to oxidative stress


Subject(s)
Autophagy , Colorectal Neoplasms/pathology , Cathepsins/chemistry , Photochemotherapy , Gene Expression , Cholesterol/adverse effects , Lysosomal Storage Diseases , Oxidative Stress , HT29 Cells/metabolism
19.
Braz. J. Pharm. Sci. (Online) ; 58: e19946, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383979

ABSTRACT

Abstract The present study evaluated 56 patients diagnosed with Chronic Lymphocytic Leukemia (CLL) and a control group of 44 clinically healthy subjects with no previous history of leukemia. Genetic expressions of AKT and microRNAs were evaluated by quantitative PCR (qPCR). A significant increase in AKT gene expression in patients when compared to controls was observed (p = 0.017). When the patients were stratified according to Binet subgroups, a significant difference was observed between the subgroups, with this protein kinase appearing more expressed in the B+C subgroup (p = 0.013). Regarding miRNA expression, miR-let-7b and miR-26a were reduced in CLL patients, when compared to controls. However, no significant differences were observed in these microRNA expressions between the Binet subgroups (A versus B+C). By contrast, miR-21 to miR-27a oncogenes showed no expression difference between CLL patients and controls. AKT protein kinase is involved in the signaling cascade that occurs with BCR receptor activation, leading to increased lymphocyte survival and protection against the induction of cell death in CLL. Thus, increased AKT protein kinase expression and the reduction of miR-let-7b and miR-26a, both tumor suppressors, may explain increased lymphocyte survival in CLL patients and may be promising markers for the prognostic evaluation of this disease.


Subject(s)
Humans , Male , Female , Protein Kinases , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Patients , Gene Expression/genetics , Apoptosis , MicroRNAs/pharmacology , Healthy Volunteers
20.
Biomédica (Bogotá) ; 41(4): 706-720, oct.-dic. 2021. tab, graf
Article in English | LILACS | ID: biblio-1355744

ABSTRACT

Abstract | Introduction: Broccoli (Brassica oleracea) is well known for its properties as an anticancer, antioxidant, and scavenger of free radicals. However, its benefits in enhancing spermatogenesis have not been well established. Objective: To study broccoli aqueous extract effects on sperm factors and the expression of genes Catsper1, Catsper2, Arl4a, Sox5, and Sox9 in sperm factors in mice. Materials and methods: Male mice were divided randomly into six groups: (1) Control; (2) cadmium (3 mg/kg of mouse body weight); (3) orally treated with 200 µl broccoli aqueous extract (1 g ml-1); (4) orally treated with 400 µl of broccoli aqueous extract; (5) orally treated with 200 broccoli aqueous extract plus cadmium, and (6) orally treated with 400 µl of broccoli aqueous extract plus cadmium. We analyzed the sperms factors and Catsper1, Catsper2, Arl4a, Sox5, and Sox9 gene expression. Results: An obvious improvement in sperm count and a slight enhancement in sperm motility were observed in mice treated with broccoli extract alone or with cadmium. Sperm viability was reduced by broccoli extract except for the 200 µl dose with cadmium, which significantly increased it. Interestingly, Arl4a gene expression increased in the 400 µl broccoli- treated group. Likewise, the Arl4a mRNA level in mice treated with cadmium and 200 µl of broccoli extract was higher than in the cadmium-treated mice. Furthermore, broccoli extract enhanced the mRNA level of Catsper2 and Sox5 genes in mice treated with 200 µl and 400 µl broccoli extract plus cadmium compared with the group treated solely with cadmium. Conclusion: The higher sperm count in broccoli-treated mice opens the way for the development of pharmaceutical products for infertile men.


Resumen | Introducción. El brócoli (Brassica oleracea) se conoce por sus propiedades como anticancerígeno, antioxidante y eliminador de radicales libres. Sin embargo, sus beneficios en la espermatogénesis aún no se han determinado suficientemente. Objetivo. Estudiar los efectos del extracto acuoso de brócoli sobre los factores espermáticos y la expresión de los genes Catsper1, Catsper2, Arl4a, Sox5 y Sox9 en ratones. Materiales y métodos. Los ratones machos se dividieron aleatoriamente en seis grupos: 1) control; 2) tratados con cadmio, 3 mg/kg de peso corporal; 3) tratados con 200 µl de extracto acuoso de brócoli (1 g ml-1); 4) tratados con 400 µl de extracto acuoso de brócoli; 5) tratados con 200 µl de extracto acuoso de brócoli más cadmio, y 6) tratados con 400 µl de extracto acuoso de brócoli más cadmio. El extracto acuoso de brócoli se administró por vía oral. Se analizaron los factores espermáticos y la expresión de los genes Catsper1, Catsper2, Arl4a, Sox5 y Sox9. Resultados. Se observó una mejoría obvia en el recuento y una ligera mejoría en la motilidad de los espermatozoides, en ratones tratados con extracto de brócoli solo o con cadmio. La viabilidad de los espermatozoides se redujo con el extracto de brócoli, excepto con la dosis de 200 µl más cadmio, la cual la aumentó significativamente. Curiosamente, la expresión del gen Arl4a aumentó en el grupo tratado con 400 µl del extracto. Asimismo, el ARNm del Arl4a en ratones tratados con cadmio y 200 µl del extracto, fue más abundante que en los ratones tratados solo con cadmio. Además, el extracto de brócoli aumentó la cantidad de ARNm de los genes Catsper2 y Sox5 en ratones tratados con 200 y 400 µl de extracto de brócoli más cadmio, en comparación con el grupo tratado únicamente con cadmio. Conclusión. El mayor número de espermatozoides en ratones tratados con brócoli abre el camino al desarrollo de productos farmacéuticos para hombres infértiles.


Subject(s)
Spermatogenesis , Brassica , Cadmium , Gene Expression , Mice
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