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1.
Front Endocrinol (Lausanne) ; 15: 1381093, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721148

RESUMEN

Vagal paraganglioma (VPGL) is a rare neuroendocrine tumor that originates from the paraganglion associated with the vagus nerve. VPGLs present challenges in terms of diagnostics and treatment. VPGL can occur as a hereditary tumor and, like other head and neck paragangliomas, is most frequently associated with mutations in the SDHx genes. However, data regarding the genetics of VPGL are limited. Herein, we report a rare case of a 41-year-old woman with VPGL carrying a germline variant in the FH gene. Using whole-exome sequencing, a variant, FH p.S249R, was identified; no variants were found in other PPGL susceptibility and candidate genes. Loss of heterozygosity analysis revealed the loss of the wild-type allele of the FH gene in the tumor. The pathogenic effect of the p.S249R variant on FH activity was confirmed by immunohistochemistry for S-(2-succino)cysteine (2SC). Potentially deleterious somatic variants were found in three genes, SLC7A7, ZNF225, and MED23. The latter two encode transcriptional regulators that can impact gene expression deregulation and are involved in tumor development and progression. Moreover, FH-mutated VPGL was characterized by a molecular phenotype different from SDHx-mutated PPGLs. In conclusion, the association of genetic changes in the FH gene with the development of VPGL was demonstrated. The germline variant FH: p.S249R and somatic deletion of the second allele can lead to biallelic gene damage that promotes tumor initiation. These results expand the clinical and mutation spectra of FH-related disorders and improve our understanding of the molecular genetic mechanisms underlying the pathogenesis of VPGL.


Asunto(s)
Paraganglioma , Humanos , Femenino , Adulto , Paraganglioma/genética , Paraganglioma/patología , Mutación de Línea Germinal , Neoplasias de los Nervios Craneales/genética , Neoplasias de los Nervios Craneales/patología , Secuenciación del Exoma , Enfermedades del Nervio Vago/genética , Enfermedades del Nervio Vago/patología , Ácido Anhídrido Hidrolasas/genética
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(2): 232-241, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38686720

RESUMEN

DNA is susceptible to various factors in vitro and in vivo and experience different forms of damage,among which double-strand break(DSB)is a deleterious form.To maintain the stability of genetic information,organisms have developed multiple mechanisms to repair DNA damage.Among these mechanisms,homologous recombination(HR)is praised for the high accuracy.The MRE11-RAD50-NBS1(MRN)complex plays an important role in HR and is conserved across different species.The knowledge on the MRN complex mainly came from the previous studies in Saccharomyces cerevisiae and Caenorhabditis elegans,while studies in the last decades have revealed the role of mammalian MRN complex in DNA repair of higher animals.In this review,we first introduces the MRN complex regarding the composition,structure,and roles in HR.In addition,we discuss the human diseases such as ataxia-telangiectasia-like disorder,Nijmegen breakage syndrome,and Nijmegen breakage syndrome-like disorder that are caused by dysfunctions in the MRN complex.Furthermore,we summarize the mouse models established to study the clinical phenotypes of the above diseases.


Asunto(s)
Ácido Anhídrido Hidrolasas , Proteínas de Ciclo Celular , Enzimas Reparadoras del ADN , Proteínas de Unión al ADN , Proteína Homóloga de MRE11 , Proteínas Nucleares , Humanos , Ácido Anhídrido Hidrolasas/metabolismo , Ácido Anhídrido Hidrolasas/genética , Proteína Homóloga de MRE11/metabolismo , Proteína Homóloga de MRE11/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Animales , Reparación del ADN , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/metabolismo , Síndrome de Nijmegen/metabolismo , Síndrome de Nijmegen/genética
3.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 219-224, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38650130

RESUMEN

Mitochondrial DNA damage in retinal ganglion cells (RGCs) may be closely related to lesions of glaucoma. RGCs were cultured with different concentrations of glucose and grouped into 3 groups, namely normal control (NC) group, Low-Glu group, and High-Glu group. Cell viability was measured with cell counting kit-8, and cell apoptosis was measured using flow cytometry. The DNA damage was measured with comet assay, and the morphological changes of damaged mitochondria in RGCs were observed using TEM. Western blot analyzed the expression of MRE11, RAD50, and NBS1 protein. Cell viability of RGCs in Low-Glu and High-Glu groups were lower than that of NC group in 48 and 96 h. The cell apoptosis in NC group was 4.9%, the Low-Glu group was 12.2% and High-Glu group was 24.4%. The comet imaging showed that NC cells did not have tailings, but the low-Glu and high-Glu group cells had tailings, indicating that the DNA of RGCs had been damaged. TEM, mitochondrial membrane potential, ROS, mitochondrial oxygen consumption, and ATP content detection results showed that RGCs cultured with high glucose occurred mitochondrial morphology changes and dysfunction. MRE11, RAD50, and NBS1 protein expression associated with DNA damage repair pathway in High-Glu group declined compared with Low-Glu group. Mitochondrial DNA damage caused by high glucose will result in apoptosis of retinal ganglion cells in glaucoma.


Asunto(s)
Apoptosis , Supervivencia Celular , Daño del ADN , ADN Mitocondrial , Glucosa , Potencial de la Membrana Mitocondrial , Especies Reactivas de Oxígeno , Células Ganglionares de la Retina , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Glucosa/toxicidad , Glucosa/farmacología , ADN Mitocondrial/metabolismo , ADN Mitocondrial/genética , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Adenosina Trifosfato/metabolismo , Proteína Homóloga de MRE11/metabolismo , Proteína Homóloga de MRE11/genética , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Ácido Anhídrido Hidrolasas/genética , Enzimas Reparadoras del ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Humanos , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Ensayo Cometa , Animales
4.
Development ; 151(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38512324

RESUMEN

The conserved MRE11-RAD50-NBS1/Xrs2 complex is crucial for DNA break metabolism and genome maintenance. Although hypomorphic Rad50 mutation mice showed normal meiosis, both null and hypomorphic rad50 mutation yeast displayed impaired meiosis recombination. However, the in vivo function of Rad50 in mammalian germ cells, particularly its in vivo role in the resection of meiotic double strand break (DSB) ends at the molecular level remains elusive. Here, we have established germ cell-specific Rad50 knockout mouse models to determine the role of Rad50 in mitosis and meiosis of mammalian germ cells. We find that Rad50-deficient spermatocytes exhibit defective meiotic recombination and abnormal synapsis. Mechanistically, using END-seq, we demonstrate reduced DSB formation and abnormal DSB end resection occurs in mutant spermatocytes. We further identify that deletion of Rad50 in gonocytes leads to complete loss of spermatogonial stem cells due to genotoxic stress. Taken together, our results reveal the essential role of Rad50 in mammalian germ cell meiosis and mitosis, and provide in vivo views of RAD50 function in meiotic DSB formation and end resection at the molecular level.


Asunto(s)
Roturas del ADN de Doble Cadena , Animales , Masculino , Ratones , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/metabolismo , Mutación con Pérdida de Función , Mamíferos/metabolismo , Meiosis/genética , Mutación , Espermatocitos/metabolismo , Células Germinativas/metabolismo , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo
5.
Cell Cycle ; 23(1): 92-113, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38234243

RESUMEN

The Fragile Histidine Triad Diadenosine Triphosphatase (FHIT) gene is located in the Common Fragile Site FRA3B and encodes an enzyme that hydrolyzes the dinucleotide Ap3A. Although FHIT loss is one of the most frequent copy number alterations in cancer, its relevance for cancer initiation and progression remains unclear. FHIT is frequently lost in cancers from the digestive tract, which is compatible with being a cancer driver event in these tissues. However, FHIT loss could also be a passenger event due to the inherent fragility of the FRA3B locus. Moreover, the physiological relevance of FHIT enzymatic activity and the levels of Ap3A is largely unclear. We have conducted here a systematic pan-cancer analysis of FHIT status in connection with other mutations and phenotypic alterations, and we have critically discussed our findings in connection with the literature to provide an overall view of FHIT implications in cancer.


Asunto(s)
Ácido Anhídrido Hidrolasas , Proteínas de Neoplasias , Neoplasias , Humanos , Ácido Anhídrido Hidrolasas/genética , Sitios Frágiles del Cromosoma , Proteínas de Neoplasias/genética , Neoplasias/genética
6.
Int J Mol Sci ; 24(15)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37569756

RESUMEN

DNA double-strand breaks (DSBs) are a significant threat to cell viability due to the induction of genome instability and the potential loss of genetic information. One of the key players for early DNA damage response is the conserved Mre11/Rad50 Nbs1/Xrs2 (MRN/X) complex, which is quickly recruited to the DNA's ruptured ends and is required for their tethering and their subsequent repair via different pathways. The MRN/X complex associates with several other proteins to exert its functions, but it also exploits sophisticated internal dynamic properties to orchestrate the several steps required to address the damage. In this review, we summarize the intrinsic molecular features of the MRN/X complex through biophysical, structural, and computational analyses in order to describe the conformational transitions that allow for this complex to accomplish its multiple functions.


Asunto(s)
Núcleo Celular , Roturas del ADN de Doble Cadena , Conformación Molecular , Núcleo Celular/metabolismo , Ácido Anhídrido Hidrolasas/genética , ADN/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Reparación del ADN , Enzimas Reparadoras del ADN/genética , Daño del ADN
7.
Int J Mol Sci ; 24(10)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37240339

RESUMEN

Seed germination is a complex process that is regulated by various exogenous and endogenous factors, in which abscisic acid (ABA) plays a crucial role. The triphosphate tunnel metalloenzyme (TTM) superfamily exists in all living organisms, but research on its biological role is limited. Here, we reveal that TTM2 functions in ABA-mediated seed germination. Our study indicates that TTM2 expression is enhanced but repressed by ABA during seed germination. Promoted TTM2 expression in 35S::TTM2-FLAG rescues ABA-mediated inhibition of seed germination and early seedling development and ttm2 mutants exhibit lower seed germination rate and reduced cotyledon greening compared with the wild type, revealing that the repression of TTM2 expression is required for ABA-mediated inhibition of seed germination and early seedling development. Further, ABA inhibits TTM2 expression by ABA insensitive 4 (ABI4) binding of TTM2 promoter and the ABA-insensitive phenotype of abi4-1 with higher TTM2 expression can be rescued by mutation of TTM2 in abi4-1 ttm2-1 mutant, indicating that TTM2 acts downstream of ABI4. In addition, TTM1, a homolog of TTM2, is not involved in ABA-mediated regulation of seed germination. In summary, our findings reveal that TTM2 acts as a downstream factor of ABI4 in ABA-mediated seed germination and early seedling growth.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Metaloproteínas , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Factores de Transcripción/metabolismo , Germinación/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Semillas/metabolismo , Plantones/metabolismo , Metaloproteínas/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácido Anhídrido Hidrolasas/genética
8.
Zool Res ; 44(3): 636-649, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37070589

RESUMEN

Telomeres are nucleoprotein structures located at the end of each chromosome, which function in terminal protection and genomic stability. Telomeric damage is closely related to replicative senescence in vitro and physical aging in vivo. As relatively long-lived mammals based on body size, bats display unique telomeric patterns, including the up-regulation of genes involved in alternative lengthening of telomeres (ALT), DNA repair, and DNA replication. At present, however, the relevant molecular mechanisms remain unclear. In this study, we performed cross-species comparison and identified EPAS1, a well-defined oxygen response gene, as a key telomeric protector in bat fibroblasts. Bat fibroblasts showed high expression of EPAS1, which enhanced the transcription of shelterin components TRF1 and TRF2, as well as DNA repair factor RAD50, conferring bat fibroblasts with resistance to senescence during long-term consecutive expansion. Based on a human single-cell transcriptome atlas, we found that EPAS1 was predominantly expressed in the human pulmonary endothelial cell subpopulation. Using in vitro-cultured human pulmonary endothelial cells, we confirmed the functional and mechanistic conservation of EPAS1 in telomeric protection between bats and humans. In addition, the EPAS1 agonist M1001 was shown to be a protective compound against bleomycin-induced pulmonary telomeric damage and senescence. In conclusion, we identified a potential mechanism for regulating telomere stability in human pulmonary diseases associated with aging, drawing insights from the longevity of bats.


Asunto(s)
Quirópteros , Humanos , Animales , Quirópteros/genética , Proteína 2 de Unión a Repeticiones Teloméricas/genética , Células Endoteliales/metabolismo , Proteína 1 de Unión a Repeticiones Teloméricas/química , Proteína 1 de Unión a Repeticiones Teloméricas/genética , Proteína 1 de Unión a Repeticiones Teloméricas/metabolismo , Telómero/genética , Telómero/metabolismo , Proteínas de Unión al ADN/genética , Ácido Anhídrido Hidrolasas/genética
9.
Int J Mol Sci ; 24(6)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36982687

RESUMEN

The MRE11, RAD50, and NBN genes encode for the nuclear MRN protein complex, which senses the DNA double strand breaks and initiates the DNA repair. The MRN complex also participates in the activation of ATM kinase, which coordinates DNA repair with the p53-dependent cell cycle checkpoint arrest. Carriers of homozygous germline pathogenic variants in the MRN complex genes or compound heterozygotes develop phenotypically distinct rare autosomal recessive syndromes characterized by chromosomal instability and neurological symptoms. Heterozygous germline alterations in the MRN complex genes have been associated with a poorly-specified predisposition to various cancer types. Somatic alterations in the MRN complex genes may represent valuable predictive and prognostic biomarkers in cancer patients. MRN complex genes have been targeted in several next-generation sequencing panels for cancer and neurological disorders, but interpretation of the identified alterations is challenging due to the complexity of MRN complex function in the DNA damage response. In this review, we outline the structural characteristics of the MRE11, RAD50 and NBN proteins, the assembly and functions of the MRN complex from the perspective of clinical interpretation of germline and somatic alterations in the MRE11, RAD50 and NBN genes.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Supresoras de Tumor , Humanos , Proteínas de Ciclo Celular/metabolismo , Proteínas Supresoras de Tumor/genética , Proteína Homóloga de MRE11/genética , Proteína Homóloga de MRE11/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Reparación del ADN/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo
10.
Otolaryngol Head Neck Surg ; 168(6): 1324-1337, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36802061

RESUMEN

OBJECTIVE: The objective of this meta-analysis is to evaluate the impact of genetic polymorphisms on platinum-based chemotherapy (PBC)-induced ototoxicity. DATA SOURCES: Systematic searches of PubMed, Embase, Cochrane, and Web of Science were conducted from the inception of the databases to May 31, 2022. Abstracts and presentations from conferences were also reviewed. REVIEW METHODS: Four investigators independently extracted data in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Differences in the prevalence of PBC-induced ototoxicity between reference and variant (i) genotypes and (ii) alleles were analyzed. The overall effect size was presented using the random-effects model as an odds ratio (OR) with a 95% confidence interval (CI). RESULTS: From 32 included articles, 59 single nucleotide polymorphisms on 28 genes were identified, with 4406 total unique participants. For allele frequency analysis, the A allele in ACYP2 rs1872328 was positively associated with ototoxicity (OR: 2.61; 95% CI: 1.06-6.43; n = 2518). Upon limiting to cisplatin use only, the T allele of COMT rs4646316 and COMT rs9332377 revealed significant results. For genotype frequency analysis, the CT/TT genotype in ERCC2 rs1799793 demonstrated an otoprotective effect (OR: 0.50; 95% CI: 0.27-0.94; n = 176). Excluding studies using carboplatin or concomitant radiotherapy revealed significant effects with COMT rs4646316, GSTP1 rs1965, and XPC rs2228001. Major sources of variations between studies include differences in patient demographics, ototoxicity grading systems, and treatment protocols. CONCLUSION: Our meta-analysis presents polymorphisms that exert ototoxic or otoprotective effects in patients undergoing PBC. Importantly, several of these alleles are observed at high frequencies globally, highlighting the potential for polygenic screening and cumulative risk evaluation for personalized care.


Asunto(s)
Antineoplásicos , Ototoxicidad , Humanos , Antineoplásicos/uso terapéutico , Ototoxicidad/tratamiento farmacológico , Platino (Metal) , Cisplatino , Polimorfismo de Nucleótido Simple , Proteína de la Xerodermia Pigmentosa del Grupo D/genética , Ácido Anhídrido Hidrolasas/genética
11.
Mol Cell ; 83(2): 160-162, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36669476

RESUMEN

In this issue of Molecular Cell, Rotheneder et al.1 elucidate the eukaroytic Mre11-Rad50-Nbs1 (MRN) complex quaternary architecture, which together with cryo-EM structures of bacterial Mre11-Rad50-DNA complexes,2 resolves the basis for MRN assembly and its broad nuclease specificity regulating DNA double-strand break repair.


Asunto(s)
Proteínas de Ciclo Celular , Enzimas Reparadoras del ADN , Proteína Homóloga de MRE11/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Reparación del ADN , ADN/genética , Ácido Anhídrido Hidrolasas/genética
12.
Mol Cell ; 83(2): 167-185.e9, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36577401

RESUMEN

The DNA double-strand break repair complex Mre11-Rad50-Nbs1 (MRN) detects and nucleolytically processes DNA ends, activates the ATM kinase, and tethers DNA at break sites. How MRN can act both as nuclease and scaffold protein is not well understood. The cryo-EM structure of MRN from Chaetomium thermophilum reveals a 2:2:1 complex with a single Nbs1 wrapping around the autoinhibited Mre11 nuclease dimer. MRN has two DNA-binding modes, one ATP-dependent mode for loading onto DNA ends and one ATP-independent mode through Mre11's C terminus, suggesting how it may interact with DSBs and intact DNA. MRNs two 60-nm-long coiled-coil domains form a linear rod structure, the apex of which is assembled by the two joined zinc-hook motifs. Apices from two MRN complexes can further dimerize, forming 120-nm spanning MRN-MRN structures. Our results illustrate the architecture of MRN and suggest how it mechanistically integrates catalytic and tethering functions.


Asunto(s)
Reparación del ADN , ADN , Microscopía por Crioelectrón , ADN/genética , Ácido Anhídrido Hidrolasas/genética , Roturas del ADN de Doble Cadena , Enzimas Reparadoras del ADN/metabolismo , Adenosina Trifosfato/metabolismo , Proteína Homóloga de MRE11/genética , Proteína Homóloga de MRE11/metabolismo , Proteínas de Ciclo Celular/metabolismo
13.
J Pept Sci ; 29(3): e3458, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36264037

RESUMEN

Intracellular dinucleoside polyphosphates (Npn Ns) have been known for decades but the functional role remains enigmatic. Diadenosine triphosphate (Ap3 A) is one of the most prominent examples, and its intercellular concentration was shown to increase upon cellular stress. By employment of previously reported Ap3 A-based photoaffinity-labeling probes (PALPs) in chemical proteomics, we investigated the Ap3 A interactome in the human lung carcinoma cell line H1299. The cell line is deficient of the fragile histidine triade (Fhit) protein, a hydrolase of Ap3 A and tumor suppressor. Overall, the number of identified potential interaction partners was significantly lower than in the previously investigated HEK293T cell line. Gene ontology term analysis revealed that the identified proteins participate in similar pathways as for HEK293T, but the percentage of proteins involved in RNA-related processes is higher for H1299. The obtained results highlight similarities and differences of the Ap3 A interaction network in different cell lines and give further indications regarding the importance of the presence of Fhit.


Asunto(s)
Fosfatos de Dinucleósidos , Neoplasias , Humanos , Fosfatos de Dinucleósidos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Guanosina Pentafosfato , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo , Células HEK293 , Proteómica
14.
Molecules ; 27(23)2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36500714

RESUMEN

To test whether homologous recombination repair (HRR) depends on FOXO3a, a cellular aging model of human dermal fibroblast (HDF) and tet-on flag-h-FOXO3a transgenic mice were studied. HDF cells transfected with over-expression of wt-h-FOXO3a increased the protein levels of MRE11, BRCA1, BRIP1, and RAD50, while knock-down with siFOXO3a decreased them. The protein levels of MRE11, BRCA1, BRIP1, RAD50, and RAD51 decreased during cellular aging. Chromatin immunoprecipitation (ChIP) assay was performed on FOXO3a binding accessibility to FOXO consensus sites in human MRE11, BRCA1, BRIP1, and RAD50 promoters; the results showed FOXO3a binding decreased during cellular aging. When the tet-on flag-h-FOXO3a mice were administered doxycycline orally, the protein and mRNA levels of flag-h-FOXO3a, MRE11, BRCA1, BRIP1, and RAD50 increased in a doxycycline-dose-dependent manner. In vitro HRR assays were performed by transfection with an HR vector and I-SceI vector. The mRNA levels of the recombined GFP increased after doxycycline treatment in MEF but not in wt-MEF, and increased in young HDF comparing to old HDF, indicating that FOXO3a activates HRR. Overall, these results demonstrate that MRE11, BRCA1, BRIP1, and RAD50 are transcriptional target genes for FOXO3a, and HRR activity is increased via transcriptional activation of MRE11, BRCA1, BRIP1, and RAD50 by FOXO3a.


Asunto(s)
Reparación del ADN , Reparación del ADN por Recombinación , Humanos , Ratones , Animales , Activación Transcripcional , ADN Helicasas/genética , ARN Mensajero , Proteínas de Unión al ADN/genética , Ácido Anhídrido Hidrolasas/genética , Proteína BRCA1/genética
15.
Turk J Med Sci ; 52(1): 124-130, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36161592

RESUMEN

BACKGROUND: The main aim of the study is to assess expression levels of CDH1, FHIT, PTEN, and TTPAL genes in tumors and peripheral bloods of colorectal cancer patients in staged I-IV. METHODS: Gene expression analysis of related genes were performed for tumor tissues and peripheral blood samples of 51 colorectal cancer patients and colon tissues and blood samples of 5 healthy individuals. The real-time-PCR reaction method was used for the analysis. RESULTS: Alteration of mRNA levels of related genes in tumor tissues of colorectal cancer cases was determined compared to control tissues. GAPDH and TBP were used for the normalization. While the mRNA levels of CDH1 decreased, the mRNA level of the FHIT and TTPAL genes increased in the tumor tissues. There was no PTEN gene expression difference in tumor tissues (total). The mRNA levels of the CDH1 and PTEN genes were increased while the mRNA levels of FHIT and TTPAL genes decreased in the blood (total). T he mRNA levels of the CDH1 gene decreased at each stage (I-IV) in the tumor tissues and increased at each stage (I-IV) in the blood. T he PTEN gene mRNA levels at each stage were controversial. The mRNA levels of the FHIT gene increased at stage I-II-III, decreased at stage IV in the tissues and decreased at each stage (I-IV) in the blood. The mRNA levels of TTPAL gene increased at each stage (I-IV) in the tissues and decreased at each stage (I-IV) in the blood.


Asunto(s)
Ácido Anhídrido Hidrolasas , Neoplasias Colorrectales , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo , Antígenos CD/genética , Cadherinas/genética , Neoplasias Colorrectales/patología , Humanos , Proteínas de Neoplasias , Fosfohidrolasa PTEN/genética , ARN Mensajero/genética
16.
Mol Cell ; 82(18): 3513-3522.e6, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-35987200

RESUMEN

DNA double-strand breaks (DSBs) threaten genome stability and are linked to tumorigenesis in humans. Repair of DSBs requires the removal of attached proteins and hairpins through a poorly understood but physiologically critical endonuclease activity by the Mre11-Rad50 complex. Here, we report cryoelectron microscopy (cryo-EM) structures of the bacterial Mre11-Rad50 homolog SbcCD bound to a protein-blocked DNA end and a DNA hairpin. The structures reveal that Mre11-Rad50 bends internal DNA for endonucleolytic cleavage and show how internal DNA, DNA ends, and hairpins are processed through a similar ATP-regulated conformational state. Furthermore, Mre11-Rad50 is loaded onto blocked DNA ends with Mre11 pointing away from the block, explaining the distinct biochemistries of 3' → 5' exonucleolytic and endonucleolytic incision through the way Mre11-Rad50 interacts with diverse DNA ends. In summary, our results unify Mre11-Rad50's enigmatic nuclease diversity within a single structural framework and reveal how blocked DNA ends and hairpins are processed.


Asunto(s)
Proteínas de Unión al ADN , ADN , Proteína Homóloga de MRE11/química , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo , Adenosina Trifosfato/metabolismo , Microscopía por Crioelectrón , ADN/metabolismo , Reparación del ADN , Proteínas de Unión al ADN/metabolismo , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/metabolismo , Endonucleasas/genética , Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/metabolismo , Humanos , Conformación de Ácido Nucleico
17.
Nucleosides Nucleotides Nucleic Acids ; 41(11): 1205-1223, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35797106

RESUMEN

To provide a comprehensive account of the association of ACYP2 gene polymorphisms with susceptibility to cancer. A literature search for eligible candidate gene studies published before April 20, 2022 was conducted in the PubMed, Medline and Web of Science. The following combinations of main keywords were used: (ACYP2 OR acylphosphatase 2) AND (polymorphism OR mutation OR variation OR SNP OR genotype) AND (cancer OR tumor OR neoplasm OR malignancy OR carcinoma OR adenocarcinoma). Potential sources of heterogeneity were sought out via subgroup and sensitivity analysis. Publication bias were also estimated. Overall, a total of 10 articles with 5,230 cases and 5,086 controls for thirteen polymorphisms of ACYP2 gene were enrolled. We found that ACYP2 rs11125529, rs11896604, rs12615793, rs17045754, rs6713088, rs843645, rs843706, rs843711 and rs843752 were correlated with an increased risk of cancer. However, we found that ACYP2 rs12621038 might have less susceptibility to cancer. While for other polymorphisms, the results showed no significant association with cancer risk. ACYP2 rs11125529, rs11896604, rs12615793, rs17045754, rs6713088, rs843645, rs843706, rs843711 and rs843752 are associated with cancer risk. ACYP2 rs12621038 polymorphism is inversely associated with cancer risk.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias , Humanos , Polimorfismo de Nucleótido Simple , Haplotipos , Pueblo Asiatico , Ácido Anhídrido Hidrolasas/genética , Estudios de Casos y Controles , Neoplasias/genética
18.
J Am Chem Soc ; 144(19): 8613-8623, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35522782

RESUMEN

The tumor suppressor protein fragile histidine triad (Fhit) is known to be associated with genomic instability and apoptosis. The tumor-suppressive function of Fhit depends on the interaction with the alarmone diadenosine triphosphate (Ap3A), a noncanonical nucleotide whose concentration increases upon cellular stress. How the Fhit-Ap3A complex exerts its signaling function is unknown. Here, guided by a chemical proteomics approach employing a synthetic stable Fhit-Ap3A complex, we found that the Fhit-Ap3A complex, but not Fhit or Ap3A alone, impedes translation. Our findings provide a mechanistic model in which Fhit translocates from the nucleolus into the cytosol upon stress to form an Fhit-Ap3A complex. The Fhit-Ap3A complex impedes translation both in vitro and in vivo, resulting in reduced cell viability. Overall, our findings provide a mechanistic model by which the tumor suppressor Fhit collaborates with the alarmone Ap3A to regulate cellular proliferation.


Asunto(s)
Ácido Anhídrido Hidrolasas , Proteínas de Neoplasias , Ácido Anhídrido Hidrolasas/genética , Ácido Anhídrido Hidrolasas/metabolismo , Guanosina Pentafosfato , Proteínas de Neoplasias/metabolismo , Proteómica , Transducción de Señal
19.
Horm Mol Biol Clin Investig ; 43(3): 297-306, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35446515

RESUMEN

BACKGROUND: Although obesity and T2DM comorbidity is too frequent, the molecular basis of diabetic obesity is largely unexplained and barely investigated. MATERIALS: Cross-sectional studies were conducted in Kingdom of Saudi Arabia (KSA) in 2013 and Kuwait in 2019. Fasting blood samples were obtained from a total of 216 T2DM patients (104 from KSA) and 193 nondiabetic subjects (93 from KSA) after their consents. Eight SNPs in 5 genes known to be associated with both obesity and T2DM, ghrelin (GHRL) and growth hormone secretagogue receptor -GHSR (KSA) and telomeres maintenance genes (Kuwait) were genotyped by rtPCR. Both patients and controls were grouped into obese and non-obese and sub-grouped into 4-BMI- grades: normal, overweight (OW), obese (OBS) and severely obese (SOBS). RESULTS: Showed that the only SNP which was distinguished between all groups/subgroups in all study subjects was the ACYP2 rs6713088G/C, where the common CC genotype was under-expressed in the obese compared to non-obese diabetics (17.8% vs. 40.4%, p 0.01) and between the 4-BMI-grade (p 0.025). Interestingly the same genotype was over-expressed in obese compared to non-obese non-diabetics (50% vs. 27.6%, p 0.04). Furthermore, the GHRL (rs27647C/T), GHSR (rs509030G/C) and TERC (rs12696304G/C) MAFs were significantly low in normal BMI patients; p=0.034, 0.008 and 0.011, respectively. CONCLUSIONS: This is the first report about the molecular distinction between the obese and non-obese diabetics, it showed the association of rs6713088G/C mutant allele with diabetic obesity, while the GHRL, GHSR and TERC SNPs were differentially expressed based on the BMI-grades.


Asunto(s)
Diabetes Mellitus Tipo 2 , Receptores de Ghrelina , Ácido Anhídrido Hidrolasas/genética , Proteínas Portadoras , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Ghrelina/genética , Humanos , Obesidad/complicaciones , Obesidad/genética , Polimorfismo de Nucleótido Simple , Receptores de Ghrelina/genética , Telómero/genética
20.
Neuroendocrinology ; 112(12): 1168-1176, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35472852

RESUMEN

INTRODUCTION: Telomere length (TL) is a potential indicator of cancer predisposition; however, the multitude of techniques used to measure it causes the results to be heterogeneous and, in some cases, controversial. In the last years, several studies adopted a strategy based on TL-associated genetic variants to generate a polygenic score, often referred as teloscore, used in lieu of direct TL measurement. For pancreatic neuroendocrine neoplasms (PanNEN), this strategy has not been attempted yet. METHODS: A teloscore was generated using 11 SNPs (NAF1-rs7675998, ZNF676-rs409627, TERC-rs10936599, CTC1-rs3027234, PXK-rs6772228, DHX35-rs6028466, OBFC1-rs9420907, ZNF208-rs8105767, ACYP2-rs11125529, TERT-rs2736100, and ZBTB46-rs755017), and 291 PanNEN cases and 1,686 controls collected by the PANcreatic Disease ReseArch (PANDoRA) consortium were genotyped to analyse the association of the teloscore and its individual SNPs with the risk of developing PanNEN. RESULTS: An association between genetically determined long telomeres and the risk of developing PanNEN (OR = 1.99, CI: 1.33-2.98, p = 0.0008) for highest versus median (third) quintile was observed. In addition, two novel SNPs associated with PanNEN risk were identified: ZNF676-rs409627 (ORC/C_vs_G/G = 2.27, CI: 1.58-3.27, p = 8.80 × 10-6) and TERT-rs2736100 (ORC/A_vs_C/C = 2.03, CI: 1.42-2.91, p = 1.06 × 10-4). CONCLUSION: In conclusion, this study provides for the first time a clear indication of the association between long genetically determined telomeres and increased risk of developing PanNEN.


Asunto(s)
Neoplasias , Neoplasias Pancreáticas , Humanos , Estudio de Asociación del Genoma Completo , Estudios de Casos y Controles , Telómero/genética , Polimorfismo de Nucleótido Simple/genética , Neoplasias Pancreáticas/genética , Ácido Anhídrido Hidrolasas/genética
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