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1.
Acta Cir Bras ; 39: e396124, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39356932

RESUMO

PURPOSE: To examine whether isoflurane preconditioning (IsoP) has a protective effect against renal ischemia/reperfusion injury (I/RI) in diabetic conditions and to further clarify the underlying mechanisms. METHODS: Control and streptozotocin-induced diabetic rats were randomly assigned to five groups, as follows: normal sham, normal I/R, diabetic sham, diabetic I/R, and diabetic I/R + isoflurane. Renal I/RI was induced by clamping renal pedicle for 45 min followed by reperfusion for 24 h. IsoP was achieved by exposing the rats to 2% isoflurane for 30 min before vascular occlusion. Kidneys and blood were collected after reperfusion for further analysis. Renal histology, blood urea nitrogen, serum creatinine, oxidative stress, inflammatory cytokines, and renal cell apoptosis were assessed. Furthermore, the expression of brahma related gene 1 (Brg1), nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and nuclear factor-κB (NF-κB) were determined. RESULTS: Compared with control, diabetic rats undergoing I/R presented more severe renal injury, oxidative stress, inflammatory reaction, and apoptosis with the impairment of Brg1/Nrf2/HO-1 signaling. All these alterations were significantly attenuated by pretreatment with isoflurane. CONCLUSIONS: These findings suggest that isoflurane could alleviate renal I/RI in diabetes, possibly through improving Brg1/Nrf2/HO-1 signaling.


Assuntos
Apoptose , Diabetes Mellitus Experimental , Precondicionamento Isquêmico , Isoflurano , Traumatismo por Reperfusão , Transdução de Sinais , Fatores de Transcrição , Animais , Masculino , Ratos , Anestésicos Inalatórios/farmacologia , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , DNA Helicases/metabolismo , Heme Oxigenase-1/metabolismo , Precondicionamento Isquêmico/métodos , Isoflurano/farmacologia , Rim/efeitos dos fármacos , Rim/irrigação sanguínea , Rim/patologia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
2.
Biol Res ; 57(1): 68, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342328

RESUMO

BACKGROUND: Müllerian duct anomalies (MDAs) are congenital developmental disorders that present as a series of abnormalities within the reproductive tracts of females. Genetic factors are linked to MDAs and recent advancements in whole-exome sequencing (WES) provide innovative perspectives in this field. However, relevant mechanism has only been investigated in a restricted manner without clear elucidation of respective observations. METHODS: Our previous study reported that 2 of 12 patients with MDAs harbored the CHD1L variant c.348-1G>C. Subsequently, an additional 85 MDAs patients were recruited. Variants in CHD1L were screened through the in-house database of WES performed in the cohort and two cases were identified. One presented with partial septate uterus with left renal agenesis and the other with complete septate uterus, duplicated cervices and longitudinal vaginal septum. The pathogenicity of the discovered variants was further assessed by molecular dynamics simulation and various functional assays. RESULTS: Ultimately, two novel heterozygous CHD1L variants, including a missense variant c.956G>A (p.R319Q) and a nonsense variant c.1831C>T (p.R611*) were observed. The variants were absent in 100 controls. Altogether, the contribution yield of CHD1L to MDAs was calculated as 4.12% (4/97). All three variants were assessed as pathogenic through various functional analysis. The splice-site variant c.348-1G>C resulted in a 11 bp sequence skipping in exon 4 of CHD1L and led to nonsense mediated decay of its transcripts. Unlike WT CHD1L, the truncated R611* protein mislocalized to the cytoplasm, abolish the ability of CHD1L to promote cell migration and failed to interact with PARP1 owing to the loss of macro domain. The R319Q variant exhibited conformational disparities and showed abnormal protein recruitment behavior through laser microirradiation comparing with the WT CHD1L. All these variants impaired the CHD1L function in DNA damage repair, thus participating in MDAs. CONCLUSIONS: The current study not only expands the mutational spectrum of CHD1L in MDAs but determines three variants as pathogenic according to ACMG guidelines with reliable functional evidence. Additionally, the impairment in DNA damage repair is an underlying mechanism involved in MDAs.


Assuntos
DNA Helicases , Proteínas de Ligação a DNA , Ductos Paramesonéfricos , Feminino , Humanos , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Sequenciamento do Exoma , Ductos Paramesonéfricos/anormalidades , Mutação , Mutação de Sentido Incorreto
3.
Mol Biol Rep ; 51(1): 754, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874681

RESUMO

BACKGROUND: Telomeropathies are a group of inherited disorders caused by germline pathogenic variants in genes involved in telomere maintenance, resulting in excessive telomere attrition that affects several tissues, including hematopoiesis. RecQ and RTEL1 helicases contribute to telomere maintenance by unwinding telomeric structures such as G-quadruplexes (G4), preventing replication defects. Germline RTEL1 variants also are etiologic in telomeropathies. METHODS AND RESULTS: Here we investigated the expression of RecQ (RECQL1, BLM, WRN, RECQL4, and RECQL5) and RTEL1 helicase genes in peripheral blood mononuclear cells (PBMCs) from human telomeropathy patients. The mRNA expression levels of all RecQ helicases, but not RTEL1, were significantly downregulated in patients' primary cells. Reduced RecQ expression was not attributable to cell proliferative exhaustion, as RecQ helicases were not attenuated in T cells exhausted in vitro. An additional fifteen genes involved in DNA damage repair and RecQ functional partners also were downregulated in the telomeropathy cells. CONCLUSION: These findings indicate that the expression of RecQ helicases and functional partners involved in DNA repair is downregulated in PBMCs of telomeropathy patients.


Assuntos
Leucócitos Mononucleares , RecQ Helicases , Adulto , Feminino , Humanos , Masculino , DNA Helicases/genética , DNA Helicases/metabolismo , Reparo do DNA/genética , Leucócitos Mononucleares/metabolismo , RecQ Helicases/genética , RecQ Helicases/metabolismo , Telômero/metabolismo , Telômero/genética , Homeostase do Telômero/genética
4.
Am J Med Genet A ; 194(6): e63561, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38352994

RESUMO

CHARGE syndrome is a rare autosomal dominant syndrome characterized by multiple congenital anomalies including coloboma, heart defects, ear anomalies, and developmental delay, caused by pathogenic variants in the CHD7 gene. The discovery of the molecular basis of this syndrome increased the number of cases reported and expanded the phenotype and clinical variability. Limb anomalies are occasional clinical findings in this syndrome, present in about 30% of reported cases. The occurrence of limb anomalies in this syndrome suggests that it should be considered as part of the phenotypic spectrum. Here, we describe an individual with CHARGE syndrome presenting unilateral monodactyly.


Assuntos
Síndrome CHARGE , DNA Helicases , Fenótipo , Humanos , Síndrome CHARGE/genética , Síndrome CHARGE/diagnóstico , Síndrome CHARGE/patologia , Síndrome CHARGE/complicações , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Masculino , Feminino , Mutação , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/patologia , Deformidades Congênitas dos Membros/diagnóstico
5.
Nucleic Acids Res ; 51(20): 11213-11224, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37823592

RESUMO

The presence of ATP is known to stimulate helicase activity of the Dengue Virus Non-structural protein 3 helicase (NS3h), and the presence of RNA stimulates NS3h ATPase activity, however this coupling is still mechanistically unclear. Here we use atomistic models and molecular dynamics simulations to evaluate the single-stranded RNA (ssRNA)-length dependence of the NS3h-ssRNA binding affinity and its modulation by bound ATP. Considering complexes with 7, 11, 16 and 26 nucleotides (nts), we observe that both the binding affinity and its modulation by bound ATP are augmented with increased ssRNA lengths. In models with at least 11 nts bound, the binding of ATP results in a shift from a tightly bound to a weakly bound state. We find that the weakly bound state persists during both the ADP-Pi- and ADP-bound stages of the catalytic cycle. We obtain the equilibrium association constants for NS3h binding to an ssRNA 10-mer in vitro, both in the absence and presence of ADP, which further support the alternation between tightly and weakly bound states during the catalytic cycle. The length of bound ssRNA is critical for understanding the NS3h-RNA interaction as well as how it is modulated during the catalytic cycle.


Assuntos
Vírus da Dengue , Proteínas não Estruturais Virais , Trifosfato de Adenosina , Vírus da Dengue/enzimologia , DNA Helicases/metabolismo , Nucleotídeos , RNA/química , RNA Helicases/metabolismo , Proteínas não Estruturais Virais/química
6.
BMC Plant Biol ; 23(1): 467, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803262

RESUMO

BACKGROUND: The mechanisms and regulation for DNA replication in plant organelles are largely unknown, as few proteins involved in replisome assembly have been biochemically studied. A primase-helicase dubbed Twinkle (T7 gp4-like protein with intramitochondrial nucleoid localization) unwinds double-stranded DNA in metazoan mitochondria and plant organelles. Twinkle in plants is a bifunctional enzyme with an active primase module. This contrast with animal Twinkle in which the primase module is inactive. The organellar primase-helicase of Arabidopsis thaliana (AtTwinkle) harbors a primase module (AtPrimase) that consists of an RNA polymerase domain (RPD) and a Zn + + finger domain (ZFD). RESULTS: Herein, we investigate the mechanisms by which AtTwinkle recognizes its templating sequence and how primer synthesis and coupling to the organellar DNA polymerases occurs. Biochemical data show that the ZFD of the AtPrimase module is responsible for template recognition, and this recognition is achieved by residues N163, R166, and K168. The role of the ZFD in template recognition was also corroborated by swapping the RPDs of bacteriophage T7 primase and AtPrimase with their respective ZFDs. A chimeric primase harboring the ZFD of T7 primase and the RPD of AtPrimase synthesizes ribonucleotides from the T7 primase recognition sequence and conversely, a chimeric primase harboring the ZFD of AtPrimase and the RPD of T7 primase synthesizes ribonucleotides from the AtPrimase recognition sequence. A chimera harboring the RPDs of bacteriophage T7 and the ZBD of AtTwinkle efficiently synthesizes primers for the plant organellar DNA polymerase. CONCLUSIONS: We conclude that the ZFD is responsible for recognizing a single-stranded sequence and for primer hand-off into the organellar DNA polymerases active site. The primase activity of plant Twinkle is consistent with phylogeny-based reconstructions that concluded that Twinkle´s last eukaryotic common ancestor (LECA) was an enzyme with primase and helicase activities. In plants, the primase domain is active, whereas the primase activity was lost in metazoans. Our data supports the notion that AtTwinkle synthesizes primers at the lagging-strand of the organellar replication fork.


Assuntos
Arabidopsis , DNA Primase , Animais , DNA Primase/genética , DNA Primase/química , DNA Primase/metabolismo , DNA Helicases/química , DNA Helicases/genética , DNA Helicases/metabolismo , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Arabidopsis/metabolismo , Mitocôndrias/metabolismo , Dedos de Zinco , Ribonucleotídeos , Replicação do DNA , Bacteriófago T7/genética
7.
J Med Genet ; 61(1): 61-68, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37536918

RESUMO

BACKGROUND: Sarcomas are a rare and diverse group of cancers occurring mainly in young individuals for which an underlying germline genetic cause remains unclear in most cases. METHODS: Germline DNA from 177 children, adolescents and young adults with soft tissue or bone sarcomas was tested using multigene panels with 113 or 126 cancer predisposing genes (CPGs) to describe the prevalence of germline pathogenic/likely pathogenic variants (GPVs). Subsequent testing of a subset of tumours for loss of heterozygosity (LOH) evaluation was performed to investigate the clinical and molecular significance of these variants. RESULTS: GPVs were detected in 21.5% (38/177) of the patients (15.8% in children and 21.6% in adolescents and young adults), with dominant CPGs being altered in 15.2% overall. These variants were found in genes previously associated with the risk of developing sarcomas (TP53, RB1, NF1, EXT1/2) but also in genes where that risk is still emerging/limited (ERCC2, TSC2 and BRCA2) or unknown (PALB2, RAD50, FANCM and others). The detection rates of GPVs varied from 0% to 33% across sarcoma subtypes and GPV carriers were more likely to present more than one primary tumour than non-carriers (21.1%×6.5%; p=0.012). Loss of the wild-type allele was detected in 48% of tumours from GPV carriers, mostly in genes definitively associated with sarcoma risk. CONCLUSION: Our findings reveal that a high proportion of young patients with sarcomas presented a GPV in a CPG, underscoring the urgency of establishing appropriate genetic screening strategies for these individuals and their families.


Assuntos
Predisposição Genética para Doença , Sarcoma , Criança , Adulto Jovem , Adolescente , Humanos , Prevalência , Mutação em Linhagem Germinativa/genética , Sarcoma/epidemiologia , Sarcoma/genética , Células Germinativas , Proteína Grupo D do Xeroderma Pigmentoso/genética , DNA Helicases/genética
8.
Int J Mol Sci ; 24(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36835452

RESUMO

Breast cancer (BC) is the most common cancer among women worldwide. BRCA1/2 are responsible for 16-20% of the risk for hereditary BC. Other susceptibility genes have been identified; Fanconi Anemia Complementation Group M (FANCM) being one of these. Two variants in FANCM, rs144567652 and rs147021911, are associated with BC risk. These variants have been described in Finland, Italy, France, Spain, Germany, Australia, the United States, Sweden, Finnish, and the Netherlands, but not in the South American populations. Our study evaluated the association of the SNPs rs144567652 and rs147021911 with BC risk in non-carriers of BRCA1/2 mutations from a South American population. The SNPs were genotyped in 492 BRCA1/2-negative BC cases and 673 controls. Our data do not support an association between FANCM rs147021911 and rs144567652 SNPs and BC risk. Nevertheless, two BC cases, one with a family history of BC and the other with sporadic early-onset BC, were C/T heterozygotes for rs144567652. In conclusion, this is the first study related contribution of FANCM mutations and BC risk in a South American population. Nevertheless, more studies are necessary to evaluate if rs144567652 could be responsible for familial BC in BRCA1/2-negatives and for early-onset non-familial BC in Chilean BC cases.


Assuntos
Neoplasias da Mama , DNA Helicases , Predisposição Genética para Doença , Feminino , Humanos , Neoplasias da Mama/genética , Chile/epidemiologia , DNA Helicases/genética , Mutação , Idade de Início
9.
J Biomol Struct Dyn ; 41(7): 3062-3075, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35249470

RESUMO

The Rad5 protein is an SWI/SNF family ubiquitin ligase that contains an N-terminal HIRAN domain and a RING C3HC4 motif. The HIRAN domain is critical for recognition of the stalled replication fork during the replication process and acts as a sensor to initiate the damaged DNA checkpoint. It is a conserved domain widely distributed in eukaryotic organisms and is present in several DNA-binding proteins from all kingdoms. Here we showed that distant species have important differences in key residues that affect affinity for ssDNA. Based on these findings, we hypothesized that different HIRAN domains might affect fork reversal and translesion synthesis through different metabolic processes. To address this question, we predicted the tertiary structure of both yeast and human HIRAN domains using molecular modeling. Structural dynamics experiments showed that the yeast HIRAN domain exhibited higher structural denaturation than its human homolog, although both domains became stable in the presence of ssDNA. Analysis of atomic contacts revealed that a greater number of interactions between the ssDNA nucleotides and the Rad5 domain are electrostatic. Taken together, these results provide new insights into the molecular mechanism of the HIRAN domain of Rad5 and may guide us to further elucidate differences in the ancient eukaryotes HIRAN sequences and their DNA affinity.Communicated by Ramaswamy H. Sarma.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Proteínas de Ligação a DNA/química , Replicação do DNA , DNA/química , DNA de Cadeia Simples , DNA Helicases/química , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
10.
Clin Transl Oncol ; 24(10): 1940-1953, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35590122

RESUMO

PURPOSE: Distal metastases are a major cause of poor prognosis in colorectal cancer patients. Approximately 95% of metastatic colorectal cancers are defined as DNA mismatch repair proficient (pMMR). Our previous study found that miR-6511b-5p was downregulated in pMMR colorectal cancer. However, the mechanism of miR-6511b-5p in pMMR colorectal cancer metastases remain unclear. METHODS: We first used quantitative real-time PCR to evaluate the role of miR-6511b-5p in colorectal cancer. Second, we conducted invasion assays and wound healing assays to investigate the role of miR-6511b-5p and CD44 in colorectal cancer cells metastases. Third, luciferase reporter assay, in situ hybridization (ISH), and immunohistochemistry assays were performed to study the relationship between miR-6511b-5p and BRG1. Finally, real-time quantitative PCR, immunohistochemistry, and chromatin immunoprecipitation (ChIP) assays were performed to analyze the relationship between BRG1 and CD44 in colorectal cancer. RESULTS: We found that lower expression of miR-6511b-5p appeared more often in pMMR colorectal cancer patients compared with dMMR (mismatch repair deficient) cases, and was positively correlated with metastases. In vitro, overexpression of miR-6511b-5p inhibited metastasis by decreasing CD44 expression via directly targeting BRG1 in colorectal cancer. Furthermore, BRG1 knockdown decreased the expression of CD44 by promoting CD44 methylation in colorectal cancer cells. CONCLUSION: Our data suggest that miR-6511b-5p may act as a promising biomarker and treatment target for pMMR colorectal cancer, particularly in metastatic patients. Mechanistically, miR-6511b-5p suppresses invasion and migration of colorectal cancer cells through methylation of CD44 via directly targeting BRG1.


Assuntos
Neoplasias Colorretais , DNA Helicases/metabolismo , MicroRNAs , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos , Metilação , Invasividade Neoplásica
11.
Proc Natl Acad Sci U S A ; 119(15): e2109508119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35394881

RESUMO

CHARGE syndrome is a complex developmental disorder caused by mutations in the chromodomain helicase DNA-binding protein-7 (CHD7) and characterized by retarded growth and malformations in the heart and nervous system. Despite the public health relevance of this disorder, relevant cellular pathways and targets of CHD7 that relate to disease pathology are still poorly understood. Here we report that chd-7, the nematode ortholog of Chd7, is required for dauer morphogenesis, lifespan determination, stress response, and body size determination. Consistent with our discoveries, we found chd-7 to be allelic to scd-3, a previously identified dauer suppressor from the DAF-7/ tumor growth factor-ß (TGF-ß) pathway. Epistatic analysis places CHD-7 at the level of the DAF-3/DAF-5 complex, but we found that CHD-7 also directly impacts the expression of multiple components of this pathway. Transcriptomic analysis revealed that chd-7 mutants fail to repress daf-9 for execution of the dauer program. In addition, CHD-7 regulates the DBL-1/BMP pathway components and shares roles in male tail development and cuticle synthesis. To explore a potential conserved function for chd-7 in vertebrates, we used Xenopus laevis embryos, an established model to study craniofacial development. Morpholino-mediated knockdown of Chd7 led to a reduction in col2a1 messenger RNA (mRNA) levels, a collagen whose expression depends on TGF-ß signaling. Both embryonic lethality and craniofacial defects in Chd7-depleted tadpoles were partially rescued by overexpression of col2a1 mRNA. We suggest that Chd7 has conserved roles in regulation of the TGF-ß signaling pathway and pathogenic Chd7 could lead to a defective extracellular matrix deposition.


Assuntos
Síndrome CHARGE , Proteínas de Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Larva , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
12.
Mov Disord ; 37(6): 1309-1316, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35426160

RESUMO

BACKGROUND: Ataxia with oculomotor apraxia (AOA) is characterized by early-onset cerebellar ataxia associated with oculomotor apraxia. AOA1, AOA2, AOA3, and AOA4 subtypes may present pathogenic variants in APTX, SETX, PIK3R5, and PNKP genes, respectively. Mutations in XRCC1 have been found to cause autosomal recessive spinocerebellar ataxia-26 (SCAR26) now considered AOA5. OBJECTIVES: To examine a cohort of Brazilians with autosomal recessive cerebellar ataxia plus oculomotor apraxia and determine the frequencies of AOA subtypes through genetic investigation. METHODS: We evaluated clinical, biomarkers, electrophysiological, and radiological findings of 52 patients with AOA phenotype and performed a genetic panel including APTX, SETX, PIK3R5, PNKP, and XRCC1. RESULTS: We found pathogenic variants in SETX (15 patients), PNKP (12), and APTX (5). No mutations in PIK3R5 or XRCC1 were identified. CONCLUSIONS: AOA2 and AOA4 were the most common forms of AOA in Brazil. Mutations in PIK3R5 and XRCC1 were not part of this genetic spectrum. © 2022 International Parkinson and Movement Disorder Society.


Assuntos
Apraxias , Ataxia Cerebelar , Apraxias/congênito , Apraxias/genética , Ataxia/genética , Brasil , Ataxia Cerebelar/complicações , Ataxia Cerebelar/genética , Síndrome de Cogan , DNA Helicases/genética , Enzimas Reparadoras do DNA/genética , Humanos , Enzimas Multifuncionais/genética , Mutação/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , RNA Helicases/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética
13.
Breast Cancer Res Treat ; 193(2): 485-494, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35353237

RESUMO

PURPOSE: There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. METHODS: We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution cancer risk assessment program. RESULTS: The study included a convenient cohort of 173 women with invasive breast cancer (cases) and 119 women who were cancer-free at the time of ascertainment. The majority of the women self-reported as African-descended (67% for cases and 90.8% for unaffected volunteers). Thirty-seven pathogenic variants were found in 36 (20.8%) patients. While the spectrum of pathogenic variants was heterogeneous, the majority (70.3%) of the pathogenic variants were detected in high-risk genes BRCA1, BRCA2, PALB2, and TP53. Pathogenic variants were also found in the ATM, BARD1, BRIP1, FAM175A, FANCM, NBN, and SLX4 genes in 6.4% of the affected women. Four recurrent pathogenic variants were detected in 11 patients of African ancestry. Only one unaffected woman had a pathogenic variant in the RAD51C gene. Different risk assessment models examined performed well in predicting risk of carrying germline loss-of-function variants in BRCA1 and/or BRCA2 in breast cancer cases. CONCLUSION: The high prevalence and heterogenous spectrum of pathogenic variants identified among self-reported African descendants in Northeast Brazil is consistent with studies in other African ancestry populations with a high burden of aggressive young onset breast cancer. It underscores the need to integrate comprehensive cancer risk assessment and genomic testing in the management of newly diagnosed Black women with breast cancer across the African Diaspora, enabling improved cancer control in admixed underserved and understudied populations.


Assuntos
Neoplasias da Mama , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil/epidemiologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , DNA Helicases/genética , Feminino , Genes BRCA2 , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Mutação
14.
Curr Oncol ; 29(2): 411-422, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35200537

RESUMO

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare and aggressive condition that is associated with the SMARCA4 mutation and has a dismal prognosis. It is generally diagnosed in young women. Here, we report a case of a young woman with SCCOHT harboring a rare molecular finding with a highly aggressive biological behavior. The patient had a somatic SMARCB1 mutation instead of an expected SMARCA4 alteration. Even though the patient was treated with high-dose chemotherapy followed by stem cell transplantation, she evolved with disease progression and died 11 months after her first symptoms appeared. We present a literature review of this rare disease and discuss the findings in the present patient in comparison to expected molecular alterations and options for SCCOHT treatment.


Assuntos
Carcinoma de Células Pequenas , Neoplasias Pulmonares , Neoplasias Ovarianas , Tumor Rabdoide , Proteína SMARCB1 , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/terapia , DNA Helicases/genética , Evolução Fatal , Feminino , Humanos , Mutação , Proteínas Nucleares/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Ovário/patologia , Tumor Rabdoide/genética , Tumor Rabdoide/patologia , Tumor Rabdoide/terapia , Proteína SMARCB1/genética , Fatores de Transcrição/genética
15.
Hum Genomics ; 15(1): 49, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348791

RESUMO

BACKGROUND: The diagnostic process for uncommon disorders with similar manifestations is complicated and requires newer technology, like gene sequencing for a correct diagnosis. MAIN BODY: We described two brothers clinically diagnosed with Carpenter syndrome, which is a condition characterized by the premature fusion of certain skull bones (craniosynostosis), abnormalities of the fingers and toes, and other developmental problems, for which they underwent craniotomies. However, whole exome sequencing analysis concluded a novel pathological variation in the ATRX chromatin remodeler gene and protein remodeling demonstrated structural variations that decreased the function, giving a completely different diagnosis to these patients. CONCLUSION: Our study focuses on the importance of using newer technologies, such as whole exome sequencing analysis, in patients with ambiguous phenotypes.


Assuntos
Acrocefalossindactilia/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Proteínas Nucleares/genética , Proteína Nuclear Ligada ao X/genética , Talassemia alfa/genética , Acrocefalossindactilia/patologia , DNA Helicases/genética , Exoma/genética , Humanos , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Mutação/genética , Fenótipo , Sequenciamento do Exoma , Talassemia alfa/patologia
16.
Clin Transl Oncol ; 23(12): 2536-2547, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34245428

RESUMO

PURPOSE: Papillary thyroid carcinoma (PTC) represents the most common subtype of thyroid cancer (TC). This study was set out to explore the potential effect of CHD1L on PTC and type 2 diabetes mellitus (T2DM). METHODS: We searched for T2DM susceptibility genes through the GWAS database and obtained T2DM-related differentially expressed gene from the GEO database. The expression and clinical data of TC and normal samples were collated from the TCGA database. Receiver operating characteristic (ROC) curve analysis was subsequently applied to assess the sensitivity and specificity of the CHD1L for the diagnosis of PTC. The MCP-counter package in R language was then utilized to generate immune cell score to evaluate the relationship between CHD1L expression and immune cells. Then, we performed functional enrichment analysis of co-expressed genes and DEGs to determine significantly enriched GO terms and KEGG to predict the potential functions of CHD1L in PTC samples and T2DM adipose tissue. RESULTS: From two genes (ABCB9, CHD1L) were identified to be DEGs (p < 1 * 10-5) that exerted effects on survival (HR > 1, p < 0.05) in PTC and served as T2DM susceptibility genes. The gene expression matrix-based scoring of immunocytes suggested that PTC samples with high and low CHD1L expression presented with significant differences in the tumor microenvironment (TME). The enrichment analysis of CHD1L co-expressed genes and DEGs suggested that CHD1L was involved in multiple pathways to regulate the development of PTC. Among them, Kaposi sarcoma-associated herpesvirus infection, salmonella infection and TNF signaling pathways were highlighted as the three most relevant pathways. GSEA analysis, employed to analyze the genome dataset of PTC samples and T2DM adipose tissue presenting with high and low expression groups of CHD1L, suggests that these differential genes are related to chemokine signaling pathway, leukocyte transendothelial migration and TCELL receptor signaling pathway. CONCLUSION: CHD1L may potentially serve as an early diagnostic biomarker for PTC, and a target of immunotherapy for PTC and T2DM.


Assuntos
Biomarcadores Tumorais/metabolismo , Biologia Computacional/métodos , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Estudo de Associação Genômica Ampla , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Biomarcadores Tumorais/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Seguimentos , Humanos , Prognóstico , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Microambiente Tumoral
17.
Methods Mol Biol ; 2281: 313-322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33847968

RESUMO

Defects in mitochondrial DNA (mtDNA) maintenance may lead to disturbances in mitochondrial homeostasis and energy production in eukaryotic cells, causing diseases. During mtDNA replication, the mitochondrial single-stranded DNA-binding protein (mtSSB) stabilizes and protects the exposed single-stranded mtDNA from nucleolysis; perhaps more importantly, it appears to coordinate the actions of both the replicative mtDNA helicase Twinkle and DNA polymerase gamma at the replication fork. Here, we describe a helicase stimulation protocol to test in vitro the functional interaction between mtSSB and variant forms of Twinkle. We show for the first time that the C-terminal tail of Twinkle is important for such an interaction, and that it negatively regulates helicase unwinding activity in a salt-dependent manner.


Assuntos
DNA Helicases/química , DNA Helicases/metabolismo , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Mutação , Sítios de Ligação , DNA Helicases/genética , Replicação do DNA , DNA Mitocondrial/química , DNA Mitocondrial/metabolismo , DNA de Cadeia Simples/química , Proteínas de Ligação a DNA/química , Humanos , Proteínas Mitocondriais/genética , Modelos Moleculares , Ligação Proteica , Conformação Proteica
18.
Arch Biochem Biophys ; 703: 108841, 2021 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-33775623

RESUMO

ATPases belonging to the AAA+ superfamily are associated with diverse cellular activities and are mainly characterized by a nucleotide-binding domain (NBD) containing the Walker A and Walker B motifs. AAA+ proteins have a range of functions, from DNA replication to protein degradation. Rvbs, also known as RUVBLs, are AAA+ ATPases with one NBD domain and were described from human to yeast as participants of the R2TP (Rvb1-Rvb2-Tah1-Pih1) complex. Although essential for the assembly of multiprotein complexes-containing DNA and RNA, the protozoa Rvb orthologs are less studied. For the first time, this work describes the Rvbs from Leishmania major, one of the causative agents of Tegumentar leishmaniasis in human. Recombinant LmRUVBL1 and LmRUVBL2 his-tagged proteins were successfully purified and investigated using biophysical tools. LmRUVBL1 was able to form a well-folded elongated hexamer in solution, while LmRUVBL2 formed a large aggregate. However, the co-expression of LmRUVBL1 and LmRUVBL2 assembled the proteins into an elongated heterodimer in solution. Thermo-stability and fluorescence experiments indicated that the LmRUVBL1/2 heterodimer had ATPase activity in vitro. This is an interesting result because hexameric LmRUVBL1 alone had low ATPase activity. Additionally, using independent SL-RNAseq libraries, it was possible to show that both proteins are expressed in all L. major life stages. Specific antibodies obtained against LmRUVBLs identified the proteins in promastigotes and metacyclics cell extracts. Together, the results here presented are the first step towards the characterization of Leishmania Rvbs, and may contribute to the development of possible strategies to intervene against leishmaniasis, a neglected tropical disease of great medical importance.


Assuntos
Adenosina Trifosfatases/metabolismo , DNA Helicases/química , DNA Helicases/metabolismo , Leishmania major/enzimologia , Multimerização Proteica , Sequência de Aminoácidos , Dobramento de Proteína , Estrutura Quaternária de Proteína , Soluções
19.
Clin Transl Oncol ; 23(3): 591-600, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32720055

RESUMO

PURPOSE: Melanoma is a malignant skin tumor, and its incidence is rising. To explore the specific differences in benign and malignant melanoma at the genetic level, we performed a series of bioinformatics analyses, including differential gene analysis, co-expression analysis, enrichment analysis, and regulatory prediction. METHODS: The microarray data of benign and malignant melanocytes were downloaded from GEO, and 1917 differential genes were obtained by differential analysis (p < 0.05). Weighted gene co-expression network analysis obtained three functional barrier modules. The essential genes of each module are SMARTA4, HECA, and C1R. RESULTS: The results of the enrichment analysis showed that the dysfunctional module gene was mainly associated with RNA splicing and Adherens junction. Through the pivotal analysis of ncRNA, it was found that miR-448, miR-152-3p, and miR-302b-3p essentially regulate three modules, which we consider to be critical regulators. In the pivot analysis of TF, more control modules include ARID3A, E2F1, E2F3, and E2F8. CONCLUSIONS: We believe that the regulator (miR-448, miR-152-3p, miR-302b-3p) regulates the expression of the core gene SMARCA4, which in turn affects the signal transduction of the Adherens junction. It eventually leads to the deterioration of benign skin spasms into melanoma.


Assuntos
Junções Aderentes/genética , Transformação Celular Neoplásica/genética , DNA Helicases/genética , Redes Reguladoras de Genes/genética , Melanócitos , Melanoma/genética , Proteínas Nucleares/genética , Neoplasias Cutâneas/genética , Fatores de Transcrição/genética , Transformação Celular Neoplásica/patologia , Biologia Computacional , Proteínas de Ligação a DNA , Bases de Dados Genéticas , Fator de Transcrição E2F1 , Fator de Transcrição E2F3 , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Melanócitos/patologia , Melanoma/patologia , MicroRNAs , Proteínas de Neoplasias/genética , Splicing de RNA/genética , RNA Mensageiro/genética , RNA não Traduzido , Proteínas Repressoras , Transdução de Sinais , Neoplasias Cutâneas/patologia , Análise Serial de Tecidos/métodos , Melanoma Maligno Cutâneo
20.
Ann Hepatol ; 20: 100258, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32961346

RESUMO

INTRODUCTION AND AIM: Long non-coding RNA (lncRNA) has been shown to be a vital regulator of cancer progression, including hepatocellular carcinoma (HCC). However, the role of DEAD/H box protein 11 antisense RNA 1 (DDX11-AS1) in HCC remains to be further studied. MATERIAL AND METHODS: The expression levels of DDX11-AS1, miR-195-5p and metastasis-associated in colon cancer-1 (MACC1) were determined by quantitative real-time PCR (qRT-PCR). Cell counting kit-8 (CCK-8), transwell and apoptosis determination assays were used to evaluate cell proliferation, migration, invasion and apoptosis, respectively. Mice xenograft models were constructed to verify the effect of DDX11-AS1 on HCC tumor growth in vivo. Furthermore, lactate production, glucose consumption, ATP level and glucose uptake were detected to assess cell glucose metabolism. The interactions among DDX11-AS1, miR-195-5p and MACC1 were verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Moreover, western blot (WB) analysis was performed to evaluate the protein levels. RESULTS: DDX11-AS1 was upregulated in HCC tissues and cells, and its silencing could inhibit HCC cell proliferation, migration, invasion and glucose metabolism, and promote apoptosis in vitro. Also, DDX11-AS1 knockdown reduced HCC tumor growth in vivo. Besides, DDX11-AS1 could interact with miR-195-5p, and miR-195-5p inhibitor reversed the inhibitory effect of silenced DDX11-AS1 on HCC cell progression. In addition, MACC1 was a target of miR-195-5p, and its overexpression reversed the suppression effect of miR-195-5p on HCC cell progression. CONCLUSION: Our data revealed that DDX11-AS1 could act as an oncogenic regulator in HCC, providing a potential therapeutic target for HCC treatment.


Assuntos
Carcinoma Hepatocelular/patologia , RNA Helicases DEAD-box/metabolismo , DNA Helicases/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Transativadores/metabolismo , Animais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Técnicas de Cultura de Células , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , RNA Longo não Codificante
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