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1.
Transl Cancer Res ; 13(7): 3826-3841, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39145096

RESUMO

Background: Laryngeal cancer (LC), a prevalent malignant tumor of the head and neck, is characterized by a high rate of postoperative recurrence and significant treatment challenges upon recurrence, severely impacting patients' quality of life. There is a pressing need for effective biomarkers in clinical practice to predict the risk of LC recurrence and guide the development of personalized treatment plans. This study uses bioinformatics methods to explore potential biomarkers for LC recurrence, focusing on key genes and exploring their functions and mechanisms of action in LC recurrence. The aim is to provide new perspectives and evidence for clinical diagnosis, prognostic evaluation, and targeted treatment of LC. Methods: Gene expression profiles from the GSE25727 data set in the Gene Expression Omnibus database were analyzed to detect the differentially expressed genes (DEGs) between the tumor tissues of postoperative recurrent and non-recurrent early stage LC patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were also conducted. A protein-protein interaction (PPI) network and transcription factor (TF)-DEG-microRNA (miRNA) network were developed using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, with key genes selected using the Molecular Complex Detection (MCODE) plugin. A Gene Set Enrichment Analysis (GSEA) was carried out to investigate the possible mechanisms of the key genes. A retrospective analysis was conducted using the clinical data of 83 LC patients. Immunohistochemical staining was used to examine the transcription level of the key genes in the LC tumor tissues and the factors affecting postoperative recurrence. Results: A total of 248 upregulated and 34 downregulated DEGs were identified in the GSE25727 data set. The PPI network analysis identified a significant module and five candidate genes (i.e., RRAGA, SLC38A9, WDR24, ATP6V1B1, and LAMTOR3). The construction of the TF-DEG-miRNA network indicated that ATP6V1B1 might be regulated by one TF and interact with 17 miRNAs. The KEGG and GSEA analyses suggested that ATP6V1B1 may influence LC recurrence through the involvement of pro-inflammatory and pro-fibrotic mediators, glutathione metabolism, matrix metalloproteinases, immune regulation, and lymphocyte interactions. The recurrence rate of the 83 LC patients included in the study was 19.3% (16/83). The immunohistochemistry results indicated that ATP6V1B1 was highly expressed in patients with recurrent LC. The univariate and multivariate logistic regression analyses revealed that tumor stage T3 (P=0.04), tumor stage T4 (P=0.01), and a high expression of ATP6V1B1 (P=0.02) were risk factors for recurrence after surgical treatment in LC patients. Conclusions: The key genes and signaling pathways identified through the bioinformatics screening provide insights into the potential mechanisms of the pathogenesis of LC. ATP6V1B1 may promote the recurrence of LC by weakening the immune phenotype. Our findings provide a theoretical basis for further research into clinical diagnostics and treatment strategies for LC.

2.
Mol Cell Biochem ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735913

RESUMO

Early detection and effective chemotherapy for ovarian cancer, a serious gynecological malignancy, require further progress. This study aimed to investigate the molecular mechanism of ATPase H+-Transporting V1 Subunit B1 (ATP6V1B1) in ovarian cancer development and chemoresistance. Our data show that ATP6V1B1 is upregulated in ovarian cancer and correlated with decreased progression-free survival. Gain- and loss-of-function experiments demonstrated that ATP6V1B1 promotes the proliferation, migration, and invasion of ovarian cancer cells in vitro, while ATP6V1B1 knockout inhibits tumor growth in vivo. In addition, knocking down ATP6V1B1 increases the sensitivity of ovarian cancer cells to cisplatin. Mechanistic studies showed that ATP6V1B1 regulates the activation of the mTOR/autophagy pathway. Overall, our study confirmed the oncogenic role of ATP6V1B1 in ovarian cancer and revealed that ATP6V1B1 promotes ovarian cancer progression via the mTOR/autophagy axis.

3.
Int J Mol Sci ; 25(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339056

RESUMO

Patients with mutations in Cldn16 suffer from familial hypomagnesaemia with hypercalciuria and nephrocalcinosis (FHHNC) which can lead to renal insufficiency. Mice lacking claudin-16 show hypomagnesemia and hypercalciuria, but no nephrocalcinosis. Calcium oxalate and calcium phosphate are the most common insoluble calcium salts that accumulate in the kidney in the case of nephrocalcinosis, however, the formation of these salts is less favored in acidic conditions. Therefore, urine acidification has been suggested to limit the formation of calcium deposits in the kidney. Assuming that urine acidification is causative for the absence of nephrocalcinosis in the claudin-16-deficient mouse model, we aimed to alkalinize the urine of these mice by the ablation of the subunit B1 of the vesicular ATPase in addition to claudin-16. In spite of an increased urinary pH in mice lacking claudin-16 and the B1 subunit, nephrocalcinosis did not develop. Thus, urinary acidification is not the only factor preventing nephrocalcinosis in claudin-16 deficient mice.


Assuntos
Hipercalciúria , Nefrocalcinose , Humanos , Animais , Camundongos , Hipercalciúria/genética , Nefrocalcinose/genética , Cálcio , Sais , Magnésio , Concentração de Íons de Hidrogênio , Claudinas/genética
4.
Biochem Biophys Res Commun ; 699: 149551, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38277730

RESUMO

V-ATPase is an ATP hydrolysis-driven proton pump involved in the acidification of intracellular organelles and systemic acid-base homeostasis through H+ secretion in the renal collecting ducts. V-ATPase dysfunction is associated with hereditary distal renal tubular acidosis (dRTA). ATP6V1B1 encodes the B1 subunit of V-ATPase that is integral to ATP hydrolysis and subsequent H+ transport. Patients with pathogenic ATP6V1B1 mutations often exhibit an early onset of sensorineural hearing loss. However, the mechanisms underlying this association remain unclear. We employed morpholino oligonucleotide-mediated knockdown and CRISPR/Cas9 gene editing to generate Atp6v1ba-deficient (atp6v1ba-/-) zebrafish as an ortholog model for ATP6V1B1. The atp6v1ba-/- zebrafish exhibited systemic acidosis and significantly smaller otoliths compared to wild-type siblings. Moreover, deficiency in Atp6v1ba led to degeneration of inner ear hair cells, with ultrastructural changes indicative of autophagy. Our findings indicate a critical role of ATP6V1B1 in regulating lysosomal pH and autophagy in hair cells, and the results provide insights into the pathophysiology of sensorineural hearing loss in dRTA. Furthermore, this study demonstrates that the atp6v1ba-/- zebrafish model is a valuable tool for further investigation into disease mechanisms and potential therapies for acidosis-related hearing impairment.


Assuntos
Acidose Tubular Renal , Acidose , Perda Auditiva Neurossensorial , Compostos Organometálicos , ATPases Vacuolares Próton-Translocadoras , Animais , Humanos , Peixe-Zebra/metabolismo , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Perda Auditiva Neurossensorial/genética , Perda Auditiva Neurossensorial/patologia , Mutação , Acidose Tubular Renal/genética , Células Ciliadas Auditivas/patologia , Concentração de Íons de Hidrogênio , Cabelo/metabolismo , Trifosfato de Adenosina
5.
Oncol Rep ; 49(5)2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36999629

RESUMO

The vacuolar ATPase H+ transporting V1 subunit B1 (ATP6V1B1) belongs to the family of ATP6Vs, which functions to transport hydrogen ions. The expression of ATP6V1B1 and associated clinicopathological features have been linked to various cancers; however, its role in epithelial ovarian cancer (EOC) has remained to be explored. The present study aimed to unveil the function, molecular mechanisms and clinical significance of ATP6V1B1 in EOC. The mRNA levels of ATP6V1 subunits A, B1 and B2 in EOC tissues were determined using data from the Gene Expression Profiling Interactive Analysis database and RNA sequencing. Protein levels of ATP6V1B1 were evaluated through immunohistochemistry staining of EOC, borderline, benign and normal epithelial tissues. The association between ATP6V1B1 expression and clinicopathological features and prognosis of patients with EOC was analyzed. Furthermore, the biological role of ATP6V1B1 in ovarian cancer cell lines was also assessed. RNA sequencing and public dataset analyses revealed elevated ATP6V1B1 mRNA levels in EOCs. High ATP6V1B1 protein levels were also observed in EOC compared with those of borderline and benign tumors and nonadjacent normal epithelial tissues. High ATP6V1B1 expression was associated with the serous cell type, advanced International Federation of Gynecology and Obstetrics stage, high/advanced tumor grade, elevated serum cancer antigen 125 levels and platinum resistance (P<0.001, P<0.001, P=0.035, P=0.029 and P=0.011, respectively). High expression levels of ATP6V1B1 were also associated with poor overall and disease­free survival (P<0.001). Knockdown of ATP6V1B1 decreased cancer cell proliferation and colony­forming abilities (P<0.001) in vitro by inducing cell cycle arrest in G0/G1 phase. Significant upregulation of ATP6V1B1 was observed in EOC and the prognostic significance and association with chemotherapy resistance of ATP6V1B1 in EOC was demonstrated, rendering it an EOC­related biomarker for prognostic evaluation and chemotherapy resistance, as well as a potential therapeutic target for patients with EOC.


Assuntos
Neoplasias Epiteliais e Glandulares , Neoplasias Ovarianas , ATPases Vacuolares Próton-Translocadoras , Humanos , Feminino , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Prognóstico , RNA Mensageiro/genética , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo
6.
Cureus ; 14(3): e23616, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35505724

RESUMO

Nephrolithiasis (NL) and urolithiasis (UL) are usual reasons for hospitalization and presentation in pediatric outpatient departments and their incidence continues to rise worldwide. In Morocco, a previous epidemiological study done in the Fez region between January 2003 and November 2013 reported a prevalence of 0.83% of childhood UL. In two studies, heritability accounted for almost half of all NL or nephrocalcinosis (NC) prevalence. Genetic factors must be considered in the etiological diagnosis of urinary lithiasis in Morocco since the frequency of consanguineous marriages is high. Hereditary tubular disorders, especially distal renal tubular acidosis (dRTA) and Dent disease, and metabolic disorders like idiopathic hypercalciuria and hyperoxaluria are the most common causes of medullary NC. Primary hyperoxaluria type 1 (PH1), which can generate an early onset of NC, and often chronic kidney disease (CKD) should always be considered and thoroughly diagnosed. The aim of this work was to establish a molecular diagnosis of PH1 and dRTA and, thus, to predict and explain the disease phenotype in a cohort of 44 Moroccan patients with NL and/or NC by analyzing the AGXT and ATP6V1B1 genes that cause NL and/or NC when mutated. Disease phenotype was molecularly explained and solved in six of 44 individuals with NL and/or NC (13.6%). In the pediatric subgroup of individuals, a causative mutation in 16.2% was identified, whereas in the adult cohort no pathogenic mutation was detected. In our patients, PH1 was objectified in 67% of cases followed by dRTA in 33% of cases. We suggest that prompt detection and prophylactic treatment of UL are necessary to limit the risk of everlasting renal damage and thus prevent or delay the progression to CKD.

7.
Clin Genet ; 100(4): 440-446, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34159584

RESUMO

The aim of this study was to analyze the genetic variants of 51 Chinese patients with distal renal tubular acidosis (dRTA) and explore the correlation between their genotype and phenotype. Eight variants of SLC4A1, 19 variants of ATP6V0A4, and 16 variants of ATP6V1B1 have been identified, and of which 14 were novel ones. Eleven patients with autosomal dominant dRTA, and four patients with autosomal recessive dRTA were caused by genetic defects in SLC4A1; 18 and nine patients with recessive dRTA were resulted by defects in ATP6V0A4 and ATP6V1B1 respectively; no causal gene was identified in seven patients. Mutation frequency of SLC4A1 in Chinese populations was more common than Europeans. The incidence of deafness in ATP6V0A4 and ATP6V1B1 groups was 16.7% and 54.5%, respectively. The frequency of CKD in adults, children and infants was 100%, 51%, and 3%, separately. Our study will further expand the mutation spectrum of primary dRTA and provide valuable references to genetic counseling of Chinese populations.


Assuntos
Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/genética , Alelos , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Fenótipo , Substituição de Aminoácidos , China , Éxons , Estudos de Associação Genética/métodos , Humanos , Mutação , ATPases Vacuolares Próton-Translocadoras/genética
8.
Hum Mutat ; 42(9): 1153-1164, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34157794

RESUMO

Primary distal renal tubular acidosis (dRTA) is a rare tubular disease associated with variants in SLC4A1, ATP6V0A4, ATP6V1B1, FOXⅠ1, or WDR72 genes. Currently, there is growing evidence that all types of exonic variants can alter splicing regulatory elements, affecting the precursor messenger RNA (pre-mRNA) splicing process. This study was to determine the consequences of variants associated with dRTA on pre-mRNA splicing combined with predictive bioinformatics tools and minigene assay. As a result, among the 15 candidate variants, 7 variants distributed in SLC4A1 (c.1765C>T, p.Arg589Cys), ATP6V1B1 (c.368G>T, p.Gly123Val; c.370C>T, p.Arg124Trp; c.484G>T, p.Glu162* and c.1102G>A, p.Glu368Lys) and ATP6V0A4 genes (c.322C>T, p.Gln108* and c.1572G>A, p.Pro524Pro) were identified to result in complete or incomplete exon skipping by either disruption of exonic splicing enhancers (ESEs) and generation of exonic splicing silencers, or interference with the recognition of the classic splicing site, or both. To our knowledge, this is the first study on pre-mRNA splicing of exonic variants in the dRTA-related genes. These results highlight the importance of assessing the effects of exonic variants at the mRNA level and suggest that minigene analysis is an effective tool for evaluating the effects of splicing on variants in vitro.


Assuntos
Acidose Tubular Renal , ATPases Vacuolares Próton-Translocadoras , Acidose Tubular Renal/genética , Proteína 1 de Troca de Ânion do Eritrócito/genética , Éxons/genética , Fatores de Transcrição Forkhead/genética , Humanos , Proteínas/genética , Splicing de RNA/genética , ATPases Vacuolares Próton-Translocadoras/genética
9.
Pediatr Nephrol ; 36(10): 3133-3142, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33881640

RESUMO

BACKGROUND: Primary distal renal tubular acidosis (dRTA) is a rare genetic disorder caused by impaired distal mechanisms of urinary acidification. Most cases are secondary to pathogenic variants in ATP6V0A4, ATP6V1B1, and SLC4A1 genes, which encode transporters regulating acid-base balance in the collecting duct. METHODS: Retrospective study of molecular and clinical data from diagnosis and long-term follow-up (10, 20, and 40±10 years) of 16 patients with primary dRTA diagnosed in childhood. RESULTS: Molecular analyses revealed nine patients had ATP6V0A4 pathogenic variants, five in ATP6V1B1, and two in SLC4A1. A novel intragenic deletion and a common ATP6V0A4 gene variant (c.1691 + 2dupT) in ATP6V0A4 occurred in two-thirds of these patients, suggesting a founder effect. Median age at diagnosis was 3.25 months (IQR 1, 13.5), which was higher in the SLC4A1 group. Median SDS height at diagnosis was -1.02 (IQR -1.79, 0.14). Delayed clinical diagnosis was significantly related to growth failure (P = 0.01). Median SDS height at 20 years follow-up was -1.23 (IQR -1.71, -0.48), and did not significantly improve from diagnosis (P = 0.76). Kidney function declined over time: at last follow-up, 43% had moderate to severe chronic kidney disease (CKD). Adequate metabolic control was not related to CKD development. Incidence of sensorineural hearing loss (SNHL) was high in ATP6V1B1 patients, though not universal. Patients harboring ATP6V0A4 variants also developed SNHL at a high rate (80%) over time. CONCLUSIONS: Patients with dRTA can develop moderate to severe CKD over time with a high frequency despite adequate metabolic control. Early diagnosis ameliorates long-term height prognosis.


Assuntos
Acidose Tubular Renal , Perda Auditiva Neurossensorial , Insuficiência Renal Crônica , ATPases Vacuolares Próton-Translocadoras , Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/genética , Proteína 1 de Troca de Ânion do Eritrócito/genética , Humanos , Mutação , Estudos Retrospectivos , ATPases Vacuolares Próton-Translocadoras/genética
10.
Int J Pediatr Otorhinolaryngol ; 129: 109772, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31733597

RESUMO

Hereditary distal renal tubular acidosis (dRTA) is a rare disorder characterized by metabolic acidosis due to impaired renal acid excretion. To date, three genes (ATP6V1B1, ATP6V0A4 and SLC4A1) have been reported to be responsible for this genetic disorder. Notably, mutations of ATP6V1B1 gene, which encode B1-subunit of H + -ATPase pump cause distal renal tubular acidosis often, associated with sensorineural hearing loss (SNHL). Furthermore, enlarged vestibular aqueduct (EVA) was also described in some patients with ATP6V1B1 mutations. Four Algerian unrelated patients presented with dRTA and SNHL were recruited. The ATP6V1B1 gene was preferentially analyzed in all these patients by Sanger sequencing. We identified two previously reported variants in ATP6V1B1 gene: a frameshift mutation (c.1155dupC: p.(Ile386Hisfs*56) in exon 12 and a splicing mutation in intron 2 (c.175-1G > C: p?). Both mutations were homozygous in affected members. Interestingly, one patient with p.(Ile386Hisfs*56) mutation presented profound SNHL and bilateral enlarged vestibular aqueduct (EVA). Our study indicates the importance contribution of ATP6V1B1 gene mutations to the pathogenesis of the dRTA in the Algerian population and will contribute to introducing principles to predict the characteristics of the dRTA in patients. Thus, screening for this gene could allow rapid patient management and provide adequate genetic counseling.


Assuntos
Acidose Tubular Renal/genética , Perda Auditiva Neurossensorial/genética , ATPases Vacuolares Próton-Translocadoras/genética , Aqueduto Vestibular/anormalidades , Argélia , Pré-Escolar , Éxons , Feminino , Mutação da Fase de Leitura , Homozigoto , Humanos , Lactente , Íntrons , Masculino
11.
BMC Nephrol ; 19(1): 364, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558562

RESUMO

BACKGROUND: Distal renal tubular acidosis (dRTA) is a heterogeneous disorder characterized by normal anion gap metabolic acidosis. Autosomal recessive dRTA is usually caused by mutations occurring in ATP6V1B1 and ATP6V0A4 genes,encoding subunits B1 and a4 of apical H+-ATPase, respectively. The heterogeneous clinical manifestations of dRTA have been described in different ethnic groups harboring distinct mutations. Most of the reported cases are from Europe and Africa. At present, the prevalence of primary dRTA is still poorly elucidated in Chinese population. CASE PRESENTATION: A 2-year and six-month-old female patient was hospitalized because of recurrent hypokalemia, hyperchloremic metabolic acidosis and growth retardation. Laboratory investigations presented a normal anion gap hyperchloremic metabolic acidosis, hypokalemia, and inappropriate alkaline urine. Renal ultrasound indicated bilateral nephrocalcinosis. Bilateral sensorineural hearing loss (SNHL) was confirmed with moderately severe (45 dB) on the left ear and severe (80 dB) on the right ear, which was accompanied with enlarged vestibular aqueduct (EVA) on both sides. According to these findings, a diagnosis of dRTA was made. To identify the pathogenic gene mutation, all coding regions of ATP6V1B1 and ATP6V0A4 gene, including intron-exon boundaries, were analyzed using PCR followed by direct sequence analysis. The splicing variants were verified in peripheral blood leucocytes of the patient by RT-PCR. As a result, two novel heterozygous mutations in ATP6V1B1 were identified in the child. One mutation was a successive 2-nucleotide deletion in exon 2(c.133-134delTG), which caused a marked nonsense mediated mRNA decay. The other was a guanine to adenine substitution of the first nucleotide of intron 8(c.785 + 1 G > A), which led to the exclusion of exon 8. After treatment with sodium citrate, potassium citrateand citric acid, metabolic acidosis and hypokalemia were corrected, but her hearing decreased gradually during the 2 years and had to accept the use of bilateral hearing aids. CONCLUSIONS: We described two novel dRTA associated mutations in ATP6V1B1 identified in a Chinese child patient accompanying with SNHL and EVA. Our study will help to expand the understanding of this rare disease in Chinese population.


Assuntos
Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/genética , Deleção de Sequência , ATPases Vacuolares Próton-Translocadoras/genética , Povo Asiático , Sequência de Bases , Pré-Escolar , China , Feminino , Guanina , Heterozigoto , Humanos , Túbulos Renais Distais , Polimorfismo de Nucleotídeo Único , Timidina
12.
Ren Fail ; 40(1): 520-526, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30230413

RESUMO

OBJECTIVE: Primary distal renal tubular acidosis (dRTA) is a rare genetic disease characterized by distal tubular dysfunction leading to metabolic acidosis and alkaline urine. Growth retardation is a major concern in these children. The disease is caused by defects in at least three genes (SLC4A1, ATP6V0A4, and ATP6V1B1) involved in urinary distal acidification. Several series of dRTA patients from different ethnic backgrounds have been genetically studied, but genetic studies regarding Chinese population is rare. Our aim was to investigate the clinical features and genetic basis of primary dRTA in Chinese children. METHODS: Three unrelated patients with dRTA participated in our study. Next-generation sequencing was performed, and the findings were validated using the Sanger sequencing method. RESULTS: All patients exhibited hyperchloraemic metabolic acidosis, abnormally high urine pH, hypokalemia, and nephrocalcinosis. Growth retardation was observed in all patients. During the follow-up (range 1-4 years), alkali replacement therapy corrected the systemic metabolic acidosis, and two patients demonstrated normal growth. rhGH therapy was administered to patient-3 at the age of 6 years, and his growth rate was significantly improved (growth velocity 9.6 cm/yr). In total, 5 mutations were identified in our cohort of three patients, and four mutations were novel. CONCLUSIONS: We report the clinical and molecular characteristics of dRTA patients from China. The four novel mutations detected in our study extend the spectrum of gene mutations associated with primary dRTA. Furthermore, our study confirms the effect of early treatment in improving growth for dRTA patient and provides insight into the effects of rhGH on dRTA patients who were diagnosed late and exhibiting a persistent growth delay despite appropriate therapy.


Assuntos
Acidose Tubular Renal/complicações , Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/genética , Mutação de Sentido Incorreto , Proteína 1 de Troca de Ânion do Eritrócito/genética , Pré-Escolar , China , Feminino , Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/etiologia , Hormônio do Crescimento/administração & dosagem , Perda Auditiva Neurossensorial/etiologia , Humanos , Hipopotassemia/etiologia , Lactente , Masculino , Nefrocalcinose/etiologia , ATPases Vacuolares Próton-Translocadoras/genética
13.
Genet Test Mol Biomarkers ; 22(10): 599-606, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30256676

RESUMO

AIM: To analyze the variants of the potential causative genes in five Chinese patients with primary distal renal tubular acidosis (dRTA) from five unrelated families, and to explore their possible genotype-phenotype correlations, so as to raise the awareness of the disease. METHODS: Variants were identified by next generation sequencing. Clinical features and biochemical findings at the first presentation, as well as at follow-up visits were also investigated. One hundred unrelated healthy subjects were selected to evaluate each of the novel mutations found in this study. RESULTS: A total of seven different mutations in the ATP6V0A4, ATP6V1B1, and SLC4A1 genes, the three main causative genes of dRTA, were detected in 4/5 patients. In patient I a novel heterozygous intronic mutation (c.639 + 1G>A) in the ATP6V0A4 gene was identified along with a heterozygous nonsense variant (c.580C>T, p.Arg194*). Two novel heterozygous missense mutations of the ATP6V1B1 gene (c.409C>T, p.Pro137Ser; c.904C>T, p.Arg302Trp) were identified in patient II. In patient III 2 novel heterozygous duplications (c.1504dupT, p.Tyr502Leufs*22; c.2351dupT, p.Phe785Ilefs*28) were found. Thus, these three patients all were compound heterozygotes leading to dRTA. These findings are consistent with the known autosomal recessive inheritance pattern of this disease. Furthermore, a de novo heterozygous missense mutation previously reported (c.1765C>A, p.Arg589Ser) in the SLC4A1 gene was observed in patient IV. No mutations in any of the known dRTA-related causative genes were found in the patient V. CONCLUSIONS: In the present study we identified 7 mutations, including 5 novel variants, in the three genes previously correlated with dRTA, enriching the human gene mutation database (HGMD). In addition, our lack of findings in these three genes for patient V suggests that other genes may contribute to dRTA in some cases.


Assuntos
Acidose Tubular Renal/genética , Adolescente , Adulto , Proteína 1 de Troca de Ânion do Eritrócito/genética , Proteína 1 de Troca de Ânion do Eritrócito/fisiologia , Povo Asiático/genética , Criança , Pré-Escolar , China , Análise Mutacional de DNA , Éxons , Feminino , Estudos de Associação Genética/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Mutação de Sentido Incorreto , Linhagem , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/fisiologia
14.
Am J Physiol Renal Physiol ; 315(3): F429-F444, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29993276

RESUMO

The vacuolar-type H+-ATPase B1 subunit is heavily expressed in the intercalated cells of the collecting system, where it contributes to H+ transport, but has also been described in other segments of the renal tubule. This study aimed to determine the localization of the B1 subunit of the vacuolar-type H+-ATPase in the early distal nephron, encompassing thick ascending limbs (TAL) and distal convoluted tubules (DCT), in human kidney and determine whether the localization differs between rodents and humans. Antibodies directed against the H+-ATPase B1 subunit were used to determine its localization in paraffin-embedded formalin-fixed mouse, rat, and human kidneys by light microscopy and in sections of Lowicryl-embedded rat kidneys by electron microscopy. Abundant H+-ATPase B1 subunit immunoreactivity was observed in the human kidney. As expected, intercalated cells showed the strongest signal, but significant signal was also observed in apical membrane domains of the distal nephron, including TAL, macula densa, and DCT. In mouse and rat, H+-ATPase B1 subunit expression could also be detected in apical membrane domains of these segments. In rat, electron microscopy revealed that the H+-ATPase B1 subunit was located in the apical membrane. Furthermore, the H+-ATPase B1 subunit colocalized with other H+-ATPase subunits in the TAL and DCT. In conclusion, the B1 subunit is expressed in the early distal nephron. The physiological importance of H+-ATPase expression in these segments remains to be delineated in detail. The phenotype of disease-causing mutations in the B1 subunit may also relate to its presence in the TAL and DCT.


Assuntos
Túbulos Renais Distais/enzimologia , ATPases Vacuolares Próton-Translocadoras/metabolismo , Animais , Polaridade Celular , Humanos , Imuno-Histoquímica , Túbulos Renais Distais/ultraestrutura , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Especificidade da Espécie , ATPases Vacuolares Próton-Translocadoras/deficiência , ATPases Vacuolares Próton-Translocadoras/genética
15.
Pediatr Nephrol ; 33(9): 1523-1529, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29725771

RESUMO

BACKGROUND: To evaluate whether there are differences in the phenotype of primary distal renal tubular acidosis (dRTA) patients according to the causal defective gene. METHODS: Twenty-seven non-oriental patients with genetically confirmed dRTA were grouped according to the identified underlying mutations in either ATP6V1B1 (n = 10), ATP6V0A4 (n = 12), or SLC4A1 (n = 5) gene. Demographic features, growth impairment, biochemical variables and presence of deafness, nephrocalcinosis, and urolithiasis at diagnosis were compared among the three groups. RESULTS: Patients with SLC4A1 mutations presented later than those with ATP6V1B1 or ATP6V0A4 defects (120 vs. 7 and 3 months, respectively). Hearing loss at diagnosis was present in the majority of patients with ATP6V1B1 mutations, in two patients with ATP6V0A4 mutations, and in none of cases harboring SLC4A1 mutations. Serum potassium concentration (X ± SD) was higher in SLC4A1 group (3.66 ± 0.44 mEq/L) than in ATP6V0A4 group (2.96 ± 0.63 mEq/L) (p = 0.046). There were no differences in the other clinical or biochemical variables analyzed in the three groups. CONCLUSIONS: This study indicates that non-oriental patients with dRTA caused by mutations in the SLC4A1 gene present later and have normokalemia or milder hypokalemia. Hypoacusia at diagnosis is characteristically associated with ATP6V1B1 gene mutations although it may also be present in infants with ATP6V0A4 defects. Other phenotypical manifestations do not allow predicting the involved gene.


Assuntos
Acidose Tubular Renal/genética , Perda Auditiva/genética , Hipopotassemia/genética , Acidose Tubular Renal/sangue , Acidose Tubular Renal/complicações , Acidose Tubular Renal/diagnóstico , Adolescente , Idade de Início , Proteína 1 de Troca de Ânion do Eritrócito/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Perda Auditiva/diagnóstico , Humanos , Hipopotassemia/sangue , Hipopotassemia/diagnóstico , Lactente , Masculino , Mutação , Fenótipo , Potássio/sangue , Índice de Gravidade de Doença , ATPases Vacuolares Próton-Translocadoras/genética
16.
Curr Res Transl Med ; 64(1): 5-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27140593

RESUMO

BACKGROUND: Primary distal renal tubular acidosis (dRTA) is a rare genetic condition characterized by an impaired acid excretion by the intercalated cells in the renal collecting duct. Recessive forms of this disease are caused by mutations in tow major genes: ATP6V1B1 and ATP6V0A4. Causal mutations in ATP6V1B1 gene are classically associated with early sensorineural hearing loss, however cases of tubular acidosis with early deafness have also been described in patients with mutations in the ATP6V0A4 gene. METHODS: The phenotype and genotype of three Moroccan consanguineous families with dRTA and deafness were assessed. Molecular analysis was performed by PCR amplification and direct sequencing of exon 12 of ATP6V1B1 gene. RESULTS: A novel c.1169dupC frameshift mutation of ATP6V1B1 gene was identified in one family and the c.1155dupC North African mutation in the tow other families. DISCUSSION AND CONCLUSION: In this report, we propose first line genetic testing based on screening of these two mutations both located in exon 12 of ATP6V1B1 gene in Moroccan patients with recessive form of dRTA associated to precocious hearing loss. Molecular diagnosis of dRTA leads to appropriate treatment and prevention of renal failure in affected individuals and to provide genetic counseling for families at risk.


Assuntos
Acidose Tubular Renal/genética , Códon sem Sentido , Surdez/genética , Mutação da Fase de Leitura , Perda Auditiva Neurossensorial/genética , ATPases Vacuolares Próton-Translocadoras/genética , Idade de Início , Substituição de Aminoácidos , Cóclea/enzimologia , Consanguinidade , Diagnóstico Precoce , Éxons/genética , Feminino , Genes Recessivos , Humanos , Lactente , Túbulos Renais Distais/enzimologia , Masculino , Marrocos , Nefrocalcinose/genética , Linhagem , ATPases Vacuolares Próton-Translocadoras/deficiência
17.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);91(6): 583-589, nov.-dez. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769799

RESUMO

Resumo Objetivo A acidose tubular renal distal (ATRd) é caracterizada por acidose metabólica devido à excreção renal de ácido prejudicada. O objetivo deste artigo é apresentar o diagnóstico genético de quatro crianças com ATRd com uso do sequenciamento total do exoma. Métodos Selecionamos duas famílias não relacionadas, quatro crianças com ATRd e seus pais, para fazer o sequenciamento total do exoma. A audição foi preservada em ambas as crianças da família um, porém em nenhuma criança da família dois, na qual um par de gêmeas teve perda auditiva severa. Fizemos o sequenciamento total do exoma em dois conjuntos de amostras e confirmamos os achados com o método de sequenciamento de Sanger. Resultados Duas mutações foram identificadas nos genes ATP6V0A4 e ATP6V1B1. Na família um, detectamos uma nova mutação no éxon 13 do gene ATP6V0A4 com uma alteração em um nucleotídeo único GAC → TAC (c.1232G>T) que causou substituição de ácido aspártico por tirosina na posição 411. Na família dois, detectamos uma mutação recorrente do homozigoto com inserção de um par de bases (c.1149_1155insC) no éxon 12 do gene ATP6V1B1. Conclusão Nossos resultados confirmam o valor do sequenciamento total do exoma para o estudo de nefropatias genéticas complexas e permitem a identificação de mutações novas e recorrentes. Adicionalmente, demonstramos claramente pela primeira vez a aplicação desse método molecular em doenças tubulares renais.


Abstract Objective Distal renal tubular acidosis (dRTA) is characterized by metabolic acidosis due to impaired renal acid excretion. The aim of this study was to demonstrate the genetic diagnosis of four children with dRTA through use of whole-exome sequencing. Methods Two unrelated families were selected; a total of four children with dRTA and their parents, in order to perform whole-exome sequencing. Hearing was preserved in both children from the first family, but not in the second, wherein a twin pair had severe deafness. Whole-exome sequencing was performed in two pooled samples and findings were confirmed with Sanger sequencing method. Results Two mutations were identified in the ATP6V0A4 and ATP6V1B1 genes. In the first family, a novel mutation in the exon 13 of the ATP6V0A4 gene with a single nucleotide change GAC → TAC (c.1232G>T) was found, which caused a substitution of aspartic acid to tyrosine in position 411. In the second family, a homozygous recurrent mutation with one base-pair insertion (c.1149_1155insC) in exon 12 of the ATP6V1B1 gene was detected. Conclusion These results confirm the value of whole-exome sequencing for the study of rare and complex genetic nephropathies, allowing the identification of novel and recurrent mutations. Furthermore, for the first time the application of this molecular method in renal tubular diseases has been clearly demonstrated.


Assuntos
Adolescente , Criança , Feminino , Humanos , Lactente , Masculino , Acidose Tubular Renal/diagnóstico , Éxons/genética , Perda Auditiva Neurossensorial/diagnóstico , ATPases Vacuolares Próton-Translocadoras/genética , Acidose Tubular Renal/genética , Análise Mutacional de DNA , Perda Auditiva Neurossensorial/genética , Índice de Gravidade de Doença
18.
J Pediatr (Rio J) ; 91(6): 583-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26208211

RESUMO

OBJECTIVE: Distal renal tubular acidosis (dRTA) is characterized by metabolic acidosis due to impaired renal acid excretion. The aim of this study was to demonstrate the genetic diagnosis of four children with dRTA through use of whole-exome sequencing. METHODS: Two unrelated families were selected; a total of four children with dRTA and their parents, in order to perform whole-exome sequencing. Hearing was preserved in both children from the first family, but not in the second, wherein a twin pair had severe deafness. Whole-exome sequencing was performed in two pooled samples and findings were confirmed with Sanger sequencing method. RESULTS: Two mutations were identified in the ATP6V0A4 and ATP6V1B1 genes. In the first family, a novel mutation in the exon 13 of the ATP6V0A4 gene with a single nucleotide change GAC → TAC (c.1232G>T) was found, which caused a substitution of aspartic acid to tyrosine in position 411. In the second family, a homozygous recurrent mutation with one base-pair insertion (c.1149_1155insC) in exon 12 of the ATP6V1B1 gene was detected. CONCLUSION: These results confirm the value of whole-exome sequencing for the study of rare and complex genetic nephropathies, allowing the identification of novel and recurrent mutations. Furthermore, for the first time the application of this molecular method in renal tubular diseases has been clearly demonstrated.


Assuntos
Acidose Tubular Renal/diagnóstico , Éxons/genética , Perda Auditiva Neurossensorial/diagnóstico , ATPases Vacuolares Próton-Translocadoras/genética , Acidose Tubular Renal/genética , Adolescente , Criança , Análise Mutacional de DNA , Feminino , Perda Auditiva Neurossensorial/genética , Humanos , Lactente , Masculino , Índice de Gravidade de Doença
19.
J Biomol Struct Dyn ; 33(10): 2094-103, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25517796

RESUMO

Distal renal tubular acidosis (dRTA) is an autosomal recessive syndrome results defect in either proximal tubule bicarbonate reabsorption or in distal tubule H(+) secretion and is characterized by severe hyperchloraemic metabolic acidosis in childhood. dRTA is associated with functional variations in the ATP6V1B1 gene encoding ß1 subunit of H(+)-ATPase, key membrane transporters for net acid excretion of α-intercalated cells of medullary collecting ducts. In the present study, a 13-year-old male patient suffering with nephropathy and sensorineural deafness was reported in the Department of Nephrology. We predicted improper functioning of ATP6V1B1 gene could be the reason for diseased condition. Therefore, exons 3, 4, and 7 contributing active site of ATP6V1B1 gene was amplified and sequenced (Accession numbers: KF571726, KM222653). The obtained sequences were BLAST searched against the wild type ATP6V1B1 gene which showed novel mutations c.307 A > G, c.308 C > A, c.310 C > G, c.704 T > C, c.705 G > T, c.709 A > G, c.710 A > G, c.714 G > A, c.716 C > A, c.717delC, c.722 C > G, c.728insG, c.741insT, c.753G > C. These mutations resulted in the expression of truncated protein terminating at Lys 209. The mutated ATP6V1B1structure superimposed with wild type showed extensive variations with RMSD 1.336 Å and could not bind to substrate ADP leading to non-functional ATPase. These results conclusively explain these mutations in ATP6V1B1 gene resulted in structural changes causing accumulation of H(+) ions contributing to dRTA with sensorineural deafness.


Assuntos
Acidose Tubular Renal/genética , Difosfato de Adenosina/química , Perda Auditiva Neurossensorial/genética , Mutação , ATPases Vacuolares Próton-Translocadoras/química , Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/metabolismo , Acidose Tubular Renal/patologia , Adolescente , Sequência de Aminoácidos , Sequência de Bases , Códon sem Sentido , Éxons , Expressão Gênica , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/metabolismo , Perda Auditiva Neurossensorial/patologia , Humanos , Masculino , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Termodinâmica , ATPases Vacuolares Próton-Translocadoras/genética
20.
Ren Fail ; 36(8): 1226-32, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24975934

RESUMO

The objective of this study is to identify ATP6V1B1, ATP6V0A4 and SLC4A1 genes mutations and assess audiologic characteristics in six Chinese children with primary distal renal tubular acidosis from four unrelated families between the ages of 2 and 13 years. Both ATP6V0A4 and ATP6V1B1 genes were preferentially screened in all index cases by direct sequence analysis. If inconclusive then SLC4A1 gene should be analyzed for mutation. Their clinical features, hearing status and inner ear imaging structure were also investigated. Six loss-of-function mutations were identified in six patients. Two novel mutations were identified in either of ATP6V0A4 and ATP6V1B1 genes, respectively. Two probands from different kindreds with mutations in ATP6V1B1 presented early onset profound sensorineural hearing loss (SNHL) and enlarged vestibular aqueduct (EVA). Two from different families carrying ATP6V0A4 mutations manifested early onset moderate mixed HL and moderate SNHL, respectively, the former comorbid with EVA, while the latter not; however, both their elder sisters showed normal hearing and inner ear. These findings expand the spectrum of mutations in the ATP6V0A4 and ATP6V1B1 genes associated with primary dRTA. Our study confirms the association of EVA and mutations in either of these two genes. More studies are necessary to clarify the relationship between dRTA, SNHL, EVA, and gene mutations.


Assuntos
Acidose Tubular Renal/complicações , Acidose Tubular Renal/genética , Proteína 1 de Troca de Ânion do Eritrócito/genética , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/genética , Mutação , ATPases Vacuolares Próton-Translocadoras/genética , Adolescente , Povo Asiático , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Testes Auditivos , Humanos , Masculino
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