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1.
Helicobacter ; 29(1): e13031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37997013

RESUMO

BACKGROUND: Outer membrane vesicles (OMVs) are spontaneously released by Gram-negative bacteria and influence bacteria-host interactions by acting as a delivery system for bacterial components and by interacting directly with host cells. Helicobacter pylori, a pathogenic bacterium that chronically colonizes the human stomach, also sheds OMVs, and their impact on bacterial-mediated diseases is still being elucidated. MATERIALS AND METHODS: Transcriptomic profiling of the human gastric cell line MKN74 upon challenge with H. pylori OMVs compared to control and infected cells was performed using the Ion AmpliSeq™ Transcriptome Human Gene Expression Panel to understand the gene expression changes that human gastric epithelial cells might undergo when exposed to H. pylori OMVs. RESULTS: H. pylori OMVs per se modify the gene expression profile of gastric epithelial cells, adding another layer of (gene) regulation to the already complex host-bacteria interaction. The most enriched pathways include those related to amino acid metabolism, mitogen-activated protein kinase signaling, autophagy, and ferroptosis, whereas the cell cycle, DNA replication, and DNA repair were the most downregulated. The transcriptomic changes induced by OMVs were mostly similar to those induced by the parental bacteria, likely amplifying the effects of the bacterium itself. CONCLUSIONS: Our data provide a valuable portrayal of the transcriptomic remodeling of gastric cells induced by H. pylori OMVs. It demonstrates the breadth of cellular pathways and genes affected by OMVs, most previously unreported, which can be further dissected for the underlying molecular mediators and explored to understand the pathobiology of the full spectrum of H. pylori-mediated diseases.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Helicobacter pylori/fisiologia , Transcriptoma , Infecções por Helicobacter/microbiologia , Estômago , Perfilação da Expressão Gênica
2.
Molecules ; 28(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36770876

RESUMO

Heat shock protein 90 (HSP90) facilitates folding and stability and prevents the degradation of multiple client proteins. One of these HSP90 clients is BCR-ABL, the oncoprotein characteristic of chronic myeloid leukemia (CML) and the target of tyrosine kinase inhibitors, such as imatinib. Alvespimycin is an HSP90 inhibitor with better pharmacokinetic properties and fewer side effects than other similar drugs, but its role in overcoming imatinib resistance is not yet clarified. This work studied the therapeutic potential of alvespimycin in imatinib-sensitive (K562) and imatinib-resistant (K562-RC and K562-RD) CML cell lines. Metabolic activity was determined by the resazurin assay. Cell death, caspase activity, mitochondrial membrane potential, and cell cycle were evaluated by means of flow cytometry. Cell death was also analyzed by optical microscopy. HSPs expression levels were assessed by western blotting. Alvespimycin reduced metabolic activity in a time-, dose-, and cell line-dependent manner. Resistant cells were more sensitive to alvespimycin with an IC50 of 31 nM for K562-RC and 44 nM for K562-RD, compared to 50 nM for K562. This drug induced apoptosis via the mitochondrial pathway. In K562 cells, alvespimycin induced cell cycle arrest in G0/G1. As a marker of HSP90 inhibition, a significant increase in HSP70 expression was observed. Our results suggest that alvespimycin might be a new therapeutic approach to CML treatment, even in cases of resistance to imatinib.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Choque Térmico , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo
3.
Drug Metab Rev ; 54(4): 386-400, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36031813

RESUMO

Anti-angiogenic therapy is a practical approach to managing diseases with increased angiogenesis, such as cancer, maculopathies, and retinopathies. Considering the fundamental gaps in the knowledge of the vital pathways involved in angiogenesis and its inhibition and the insufficient efficiency of existing angiogenesis inhibitors, there is an increasing focus on the emergence of new therapeutic strategies aimed at inhibiting pathological angiogenesis. Angiogenesis is forming a new vascular network from existing vessels; endothelial cells (ECs), vascular lining cells, are the main actors of angiogenesis in physiological or pathological conditions. Switching from a quiescent state to a highly migratory and proliferative state during new vessel formation called "angiogenic switch" is driven by a "metabolic switch" in ECs, angiogenic growth factors, and other signals. As the characteristics of ECs change by altering the surrounding environment, they appear to have a different metabolism in a tumor microenvironment (TME). Therefore, pathological angiogenesis can be inhibited by targeting metabolic pathways. In the current review, we aim to discuss the EC metabolic pathways under normal and TME conditions to verify the suitability of targeting them with novel therapies.


Assuntos
Células Endoteliais , Neoplasias , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neoplasias/metabolismo , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Microambiente Tumoral
4.
Cytogenet Genome Res ; 162(1-2): 28-33, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35477180

RESUMO

A palette of copy number changes in long-term epilepsy-associated tumors (LEATs) have been reported, but the data are heterogeneous. To better understand the molecular basis underlying the development of LEATs, we performed array-comparative genomic hybridization analysis to investigate chromosomal imbalances across the entire genome in 8 cases of LEATs. A high number of aberrations were found in 4 patients, among which deletions predominated. Both whole-chromosome and regional abnormalities were observed, including monosomy 19, deletion of 1p, deletions of 4p, 12p, and 22q, and gain of 20p. The common altered regions are located mainly on chromosomes 19 and 4p, identifying genes potentially involved in biological processes and cellular mechanisms related to tumorigenesis. Our study highlights new genomic alterations and reinforces others previously reported, offering new molecular insights that may help in diagnosis and therapeutic decision-making.


Assuntos
Epilepsia , Neoplasias , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Epilepsia/genética , Genômica , Humanos , Monossomia , Hibridização de Ácido Nucleico
5.
Neuropathology ; 42(6): 467-482, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35844095

RESUMO

Low-grade neuroepithelial tumors (LNETs) represent an important group of central nervous system neoplasms, some of which may be associated to epilepsy. The concept of long-term epilepsy-associated tumors (LEATs) includes a heterogenous group of low-grade, cortically based tumors, associated to drug-resistant epilepsy, often requiring surgical treatment. LEATs entities can sometimes be poorly discriminated by histological features, precluding a confident classification in the absence of additional diagnostic tools. This study aimed to provide an updated review on the genomic findings and DNA methylation profiling advances in LNETs, including histological entities of LEATs. A comprehensive search strategy was conducted on PubMed, Embase, and Web of Science Core Collection. High-quality peer-reviewed original manuscripts and review articles with full-text in English, published between 2003 and 2022, were included. Results were screened based on titles and abstracts to determine suitability for inclusion, and when addressed the topic of the review was screened by full-text reading. Data extraction was performed through a qualitative content analysis approach. Most LNETs appear to be driven mainly by a single genomic abnormality and respective affected signaling pathway, including BRAF p.V600E mutations in ganglioglioma, FGFR1 abnormalities in dysembryoplastic neuroepithelial tumor, MYB alterations in angiocentric glioma, BRAF fusions in pilocytic astrocytoma, PRKCA fusions in papillary glioneuronal tumor, between others. However, these molecular alterations are not exclusive, with some overlap amongst different tumor histologies. Also, clustering analysis of DNA methylation profiles allowed the identification of biologically similar molecular groups that sometimes transcend conventional histopathological classification. The exciting developments on the molecular basis of these tumors reinforce the importance of an integrative histopathological and (epi)genetic classification, which can be translated into precision medicine approaches.


Assuntos
Neoplasias Encefálicas , Epilepsia , Ganglioglioma , Glioma , Neoplasias Neuroepiteliomatosas , Criança , Humanos , Metilação de DNA , Neoplasias Neuroepiteliomatosas/patologia , Ganglioglioma/patologia , Glioma/genética , Neoplasias Encefálicas/patologia , Epilepsia/genética , Epilepsia/patologia
6.
Ophthalmology ; 128(11): 1604-1617, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32717343

RESUMO

PURPOSE: To develop a genotype assay to assess associations with common and rare age-related macular degeneration (AMD) risk variants, to calculate an overall genetic risk score (GRS), and to identify potential misdiagnoses with inherited macular dystrophies that mimic AMD. DESIGN: Case-control study. PARTICIPANTS: Individuals (n = 4740) from 5 European cohorts. METHODS: We designed single-molecule molecular inversion probes for target selection and used next generation sequencing to sequence 87 single nucleotide polymorphisms (SNPs), coding and splice-site regions of 10 AMD-(related) genes (ARMS2, C3, C9, CD46, CFB, CFH, CFI, HTRA1, TIMP3, and SLC16A8), and 3 genes that cause inherited macular dystrophies (ABCA4, CTNNA1, and PRPH2). Genetic risk scores for common AMD risk variants were calculated based on effect size and genotype of 52 AMD-associated variants. Frequency of rare variants was compared between late AMD patients and control individuals with logistic regression analysis. MAIN OUTCOME MEASURES: Genetic risk score, association of genetic variants with AMD, and genotype-phenotype correlations. RESULTS: We observed high concordance rates between our platform and other genotyping platforms for the 69 successfully genotyped SNPs (>96%) and for the rare variants (>99%). We observed a higher GRS for patients with late AMD compared with patients with early/intermediate AMD (P < 0.001) and individuals without AMD (P < 0.001). A higher proportion of pathogenic variants in the CFH (odds ratio [OR] = 2.88; P = 0.006), CFI (OR = 4.45; P = 0.005), and C3 (OR = 6.56; P = 0.0003) genes was observed in late AMD patients compared with control individuals. In 9 patients, we identified pathogenic variants in the PRPH2, ABCA4, and CTNNA1 genes, which allowed reclassification of these patients as having inherited macular dystrophy. CONCLUSIONS: This study reports a genotype assay for common and rare AMD genetic variants, which can identify individuals at intermediate to high genetic risk of late AMD and enables differential diagnosis of AMD-mimicking dystrophies. Our study supports sequencing of CFH, CFI, and C3 genes because they harbor rare high-risk variants. Carriers of these variants could be amendable for new treatments for AMD that currently are under development.


Assuntos
DNA/genética , Proteínas do Olho/genética , Predisposição Genética para Doença , Degeneração Macular/genética , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Proteínas do Olho/metabolismo , Genótipo , Humanos , Degeneração Macular/diagnóstico , Degeneração Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de Risco
7.
Exp Dermatol ; 30(8): 1126-1134, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33205471

RESUMO

BACKGROUND: Basal cell carcinoma (BCC) has been mostly associated with sun exposure, but ionizing radiation is also a known risk factor. It is not clear if the pathogenesis of BCC, namely at a genomic and epigenetic level, differs according to the underlying triggering factors. OBJECTIVE: The present study aims to compare genetic and epigenetic changes in BCCs related to ionizing radiation and chronic sun exposure. METHODS: Tumor samples from BCCs of the scalp in patients submitted to radiotherapy to treat tinea capitis in childhood and BCCs from sun-exposed areas were analysed through array comparative genomic hybridization (array-CGH) and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) to detect copy number alterations and methylation status of specific genes. RESULTS: Genomic characterization of tumor samples revealed several copy number gains and losses in all chromosomes, with the most frequent gains observed at 2p, 6p, 12p, 14q, 15q, 18q, Xp and Yp, and the most frequent losses observed at 3q, 14q, 16p, 17q, 22q, Xp, Yp and Yq. We developed a statistical model, encompassing gains in 3p and 16p and losses in 14q and 20p, with potential to discriminate BCC samples with sporadic aetiology from BCC samples that evolve after radiotherapy in childhood for the treatment of tinea capitis, which presented statistical significance (P = 0.003). Few methylated genes were detected through MS-MLPA, most frequently RARB and CD44. CONCLUSIONS: Our study represents a step forward in the understanding of the genetic mechanisms underlying the pathogenesis of BCC and suggests potential differences according to the underlying ris k factors.


Assuntos
Carcinoma Basocelular/genética , Neoplasias Induzidas por Radiação/genética , Neoplasias Cutâneas/genética , Tinha do Couro Cabeludo/radioterapia , Adolescente , Adulto , Idoso , Carcinoma Basocelular/patologia , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Progressão da Doença , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Couro Cabeludo/patologia , Neoplasias Cutâneas/patologia , Adulto Jovem
8.
Am J Dermatopathol ; 43(6): 438-442, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33481376

RESUMO

ABSTRACT: Basal cell carcinoma (BCC) has been linked mostly to ultraviolet radiation exposure, but ionizing radiation has also been implicated in the genesis of a subset of BCCs occurring after radiotherapy. We present a 93-year-old woman with 4 BCCs of the scalp after radiotherapy for tinea capitis, diagnosed after a latency period of over 80 years. The largest lesion was located on the right temporal region and corresponded to a BCC of mixed type, with nodular, infiltrative, and micronodular components. We performed genomic study with array comparative genomic hybridization in samples from each BCC, which revealed more imbalances in the largest lesion than in the remaining ones, correlating with its higher histological complexity. Furthermore, this was the only lesion presenting loss at 2p22.3, where is mapped the BIRC6 gene associated with regulation of apoptosis, and loss at 16q24.3, where is mapped FANCA gene, responsible for DNA repair and maintenance of chromosome stability. Despite these differences, there were aberrations shared by all tumor samples, suggesting a common genetic signature. Our report describes, to the best of our knowledge, the longest latency period between exposure to radiotherapy and the diagnosis of BCC. The genomic study showed imbalances common to all tumor samples but also differences that could explain their heterogeneity in terms of histological subtype and biological potential. In addition, these differences could also be a consequence of different times in the evolution of the lesions at the moment of presentation, thus having a diverse combination of accumulated genomic imbalances.


Assuntos
Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias Induzidas por Radiação/patologia , Couro Cabeludo/patologia , Neoplasias Cutâneas/etiologia , Tinha do Couro Cabeludo/radioterapia , Idoso de 80 Anos ou mais , Feminino , Humanos
9.
Am J Med Genet A ; 182(11): 2694-2698, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32896075

RESUMO

Proximal interstitial deletions of chromosome 9p13 have been described only in a few patients with developmental delay, moderate intellectual disability, craniofacial dysmorphism, short stature, genital anomalies, and precocious puberty. To corroborate and expand these findings, we report on two novel syndromic male patients with 9p13 deletions suffering from a similar form of tremor and compare them with literature data. Despite genomic variability in deletion sizes, all patients displayed homogeneous dysmorphism and clinical manifestations, including very invalidating tremor. Furthermore, we outlined a region of around 2 Mb shared in common by all patients with nearly 70 genes, among which NPR2 might have a role in the phenotype. These data delineate interstitial 9p13 deletion syndrome with tremor as a major feature.


Assuntos
Anormalidades Múltiplas/patologia , Deleção Cromossômica , Cromossomos Humanos Par 9/genética , Fenótipo , Tremor/patologia , Anormalidades Múltiplas/genética , Adolescente , Humanos , Recém-Nascido , Masculino , Síndrome , Tremor/genética
10.
Cytogenet Genome Res ; 157(4): 213-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30974445

RESUMO

Patients with childhood acute myeloid leukemia (AML) with complex karyotypes (CKs) have a dismal outcome. However, for patients with a KMT2A rearrangement (KMT2A-r), the prognosis appears to depend on the fusion partner gene rather than the karyotype structure. Thus, a precise characterization of KMT2A-r and the fusion partner genes, especially in CKs, is of interest for managing AML. We describe the clinical and molecular features of a child who presented with a large abdominal mass, AML, and a new CK, involving chromosomes 11, 16, and 19 leading to a KMT2A-MLLT1 fusion and 2 extra copies of the ELL gene, thus resulting in the concurrent overexpression of MLLT1 and ELL. Molecular cytogenetic studies defined the karyotype as 47,XY,der(11)t(11;16)(q23.3;p11.2),der(16)t(16;19)(p11.2;p13.3),der(19)t(11;19)(q23.3;p13.3),+der(19)t(16;19)(16pter→p11.2::19p13.3→19q11::19p11→19p13.3::16p11.2→16pter). Array CGH revealed a gain of 30.5 Mb in the 16p13.3p11.2 region and a gain of 18.1 Mb in the 19p13.3p12 region. LDI-PCR demonstrated the KMT2A-MLLT1 fusion. Reverse sequence analysis showed that the MLLT1 gene was fused to the 16p11.2 region. RT-qPCR quantification revealed that ELL and MLLT1 were overexpressed (4- and 10-fold, respectively). In summary, this is a pediatric case of AML presenting a novel complex t(11;16;19) variant with overexpression of ELL and MLLT1.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Fatores de Elongação da Transcrição/genética , Translocação Genética , Criança , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 19/genética , Humanos , Cariótipo , Masculino , Proteínas de Fusão Oncogênica/genética , Regulação para Cima
11.
Int J Mol Sci ; 20(19)2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547595

RESUMO

The availability of cytogenetics and cytogenomics technologies improved the detection and identification of tumor molecular signatures as well as the understanding of cancer initiation and progression. The use of large-scale and high-throughput cytogenomics technologies has led to a fast identification of several cancer candidate biomarkers associated with diagnosis, prognosis, and therapeutics. The advent of array comparative genomic hybridization and next-generation sequencing technologies has significantly improved the knowledge about cancer biology, underlining driver genes to guide targeted therapy development, drug-resistance prediction, and pharmacogenetics. However, few of these candidate biomarkers have made the transition to the clinic with a clear benefit for the patients. Technological progress helped to demonstrate that cellular heterogeneity plays a significant role in tumor progression and resistance/sensitivity to cancer therapies, representing the major challenge of precision cancer therapy. A paradigm shift has been introduced in cancer genomics with the recent advent of single-cell sequencing, since it presents a lot of applications with a clear benefit to oncological patients, namely, detection of intra-tumoral heterogeneity, mapping clonal evolution, monitoring the development of therapy resistance, and detection of rare tumor cell populations. It seems now evident that no single biomarker could provide the whole information necessary to early detect and predict the behavior and prognosis of tumors. The promise of precision medicine is based on the molecular profiling of tumors being vital the continuous progress of high-throughput technologies and the multidisciplinary efforts to catalogue chromosomal rearrangements and genomic alterations of human cancers and to do a good interpretation of the relation genotype-phenotype.


Assuntos
Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias , Medicina de Precisão , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Prognóstico
12.
Immunology ; 145(2): 242-57, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25581844

RESUMO

The adipose tissue can make important contributions to immune function. Nevertheless, only a limited number of reports have investigated in lean hosts the immune response elicited in this tissue upon infection. Previous studies suggested that the intracellular protozoan Neospora caninum might affect adipose tissue physiology. Therefore, we investigated in mice challenged with this protozoan if immune cell populations within adipose tissue of different anatomical locations could be differently affected. Early in infection, parasites were detected in the adipose tissue and by 7 days of infection increased numbers of macrophages, regulatory T (Treg) cells and T-bet(+) cells were observed in gonadal, mesenteric, omental and subcutaneous adipose tissue. Increased expression of interferon-γ was also detected in gonadal adipose tissue of infected mice. Two months after infection, parasite DNA was no longer detected in these tissues, but T helper type 1 (Th1) cell numbers remained above control levels in the infected mice. Moreover, the Th1/Treg cell ratio was higher than that of controls in the mesenteric and subcutaneous adipose tissue. Interestingly, chronically infected mice presented a marked increase of serum leptin, a molecule that plays a role in energy balance regulation as well as in promoting Th1-type immune responses. Altogether, we show that an apicomplexa parasitic infection influences immune cellular composition of adipose tissue throughout the body as well as adipokine production, still noticed at a chronic phase of infection when parasites were already cleared from that particular tissue. This strengthens the emerging view that infections can have long-term consequences for the physiology of adipose tissue.


Assuntos
Tecido Adiposo/imunologia , Coccidiose/imunologia , Macrófagos/imunologia , Neospora/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Adipocinas/genética , Adipocinas/imunologia , Tecido Adiposo/parasitologia , Tecido Adiposo/patologia , Animais , Coccidiose/genética , Coccidiose/patologia , Imunidade Celular/genética , Interferon gama/genética , Interferon gama/imunologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/patologia , Células Th1/patologia
13.
Am J Med Genet A ; 167A(8): 1877-83, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25845712

RESUMO

Interstitial deletions of long arm of chromosome 12 are rare, and the interstitial deletion 12q21.1q22 has been reported to the best of our knowledge in only four patients. Comparing the patients reported, a characteristic phenotypic pattern (facial features like prominent forehead, short and upturned nose, low set ears, and ectodermal abnormalities) can be identified. It has been suggested to be considered a deletion syndrome [Klein et al., (2005); Am J Med Genet 138:349-354]. We report on a 34-month-old girl, who was referred to our clinic at 6 months of age, presenting at birth with axial hypotonia, enlarged anterior fontanel, ventriculomegaly, dysmorphic facies (prominent forehead, sparse hair and eyebrows, short palpebral fissures), failure to thrive and development delay. Her cytogenetic study showed an interstitial deletion of the long arm of chromosome 12: 46,XX,del(12)(q21.1q22) redefined by array comparative genomic hybridization. We compare and review our patient with the four previously reported cases, plus one with a deletion with an overlap of the chromosomal region and phenotypic similarities. As far as we know our patient is the fourth reported with this cytogenetic abnormality. This additional report allows us to support a genotype-phenotype correlation for this chromosomal abnormality.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 12 , Pré-Escolar , Feminino , Humanos , Masculino
14.
J Med Genet ; 51(9): 605-13, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25062845

RESUMO

BACKGROUND: Recently, a number of patients have been described with structural rearrangements at 3q13.31, delineating a novel microdeletion syndrome with common clinical features including developmental delay and other neurodevelopmental disorders (NDD). A smallest region of overlapping deletions (SRO) involved five RefSeq genes, including the transcription factor gene ZBTB20 and the dopamine receptor gene DRD3, considered as candidate genes for the syndrome. METHODS AND RESULTS: We used array comparative genomic hybridization and next-generation mate-pair sequencing to identify key structural rearrangements involving ZBTB20 in two patients with NDD. In a patient with developmental delay, attention-deficit hyperactivity disorder, psychosis, Tourette's syndrome and autistic traits, a de novo balanced t(3;18) translocation truncated ZBTB20. The other breakpoint did not disrupt any gene. In a second patient with developmental delay and autism, we detected the first microdeletion at 3q13.31, which truncated ZBTB20 but did not involve DRD3 or the other genes within the previously defined SRO. Zbtb20 directly represses 346 genes in the developing murine brain. Of the 342 human orthologous ZBTB20 candidate target genes, we found 68 associated with NDD. Using chromatin immunoprecipitation and quantitative PCR, we validated the in vivo binding of Zbtb20 in evolutionary conserved regions in six of these genes (Cntn4, Gad1, Nrxn1, Nrxn3, Scn2a, Snap25). CONCLUSIONS: Our study links dosage imbalance of ZBTB20 to a range of neurodevelopmental, cognitive and psychiatric disorders, likely mediated by dysregulation of multiple ZBTB20 target genes, and provides new knowledge on the genetic background of the NDD seen in the 3q13.31 microdeletion syndrome.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Dosagem de Genes/genética , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição/genética , Imunoprecipitação da Cromatina , Hibridização Genômica Comparativa , Humanos , Proteínas do Tecido Nervoso/metabolismo , Análise de Sequência de DNA/métodos , Estatísticas não Paramétricas , Fatores de Transcrição/metabolismo
15.
Tumour Biol ; 35(5): 4599-617, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24459064

RESUMO

Several genomic regions are frequently altered and associated with the type, stage and progression of urinary bladder cancer (UBC). We present the characterization of 5637, T24 and HT1376 UBC cell lines by karyotyping, fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and multiplex ligation-dependent probe amplification (MLPA) analysis. Some cytogenetic anomalies present in UBC were found in the three cell lines, such as chromosome 20 aneuploidy and the loss of 9p21. Some gene loci losses (e.g. CDKN2A) and gains (e.g. HRAS, BCL2L1 and PTPN1) were coincident across all cell lines. Although some significant heterogeneity and complexity were detected between them, their genomic profiles exhibited a similar pattern to UBC. We suggest that 5637 and HT1376 represent the E2F3/RB1 pathway due to amplification of 6p22.3, concomitant with loss of one copy of RB1 and mutation of the remaining copy. The HT1376 presented a 10q deletion involving PTEN region and no alteration of PIK3CA region which, in combination with the inactivation of TP53, bears more invasive and metastatic properties than 5637. The T24 belongs to the alternative pathway of FGFR3/CCND1 by presenting mutated HRAS and over-represented CCND1. These cell lines cover the more frequent subtypes of UBC and are reliable models that can be used, as a group, in preclinical studies.


Assuntos
Neoplasias da Bexiga Urinária/genética , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Hibridização Genômica Comparativa , Progressão da Doença , Resistência a Múltiplos Medicamentos , Feminino , Genes do Retinoblastoma , Genes p53 , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Neoplasias da Bexiga Urinária/patologia
16.
Tumour Biol ; 35(5): 4687-95, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24477574

RESUMO

Oral tumors are a growing health problem worldwide; thus, it is mandatory to establish genetic markers in order to improve diagnosis and early detection of tumors, control relapses and, ultimately, delineate individualized therapies. This study was the first to evaluate and discuss the clinical applicability of a multiplex ligation-dependent probe amplification (MLPA) probe panel directed to head and neck cancer. Thirty primary oral squamous cell tumors were analyzed using the P428 MLPA probe panel. We detected genetic imbalances in 26 patients and observed a consistent pattern of distribution of genetic alterations in terms of losses and gains for some chromosomes, particularly for chromosomes 3, 8, and 11. Regarding the latter, some specific genes were highlighted due to frequent losses of genetic material--RARB, FHIT, CSMD1, GATA4, and MTUS1--and others due to gains--MCCC1, MYC, WISP1, PTK2, CCND1, FGF4, FADD, and CTTN. We also verified that the gains of MYC and WISP1 genes seem to suggest higher propensity of tumors localized in the floor of the mouth. This study proved the value of this MLPA probe panel for a first-tier analysis of oral tumors. The probemix was developed to include target regions that have been already shown to be of diagnostic/prognostic relevance for oral tumors. Furthermore, this study emphasized several of those specific genetic targets, suggesting its importance to oral tumor development, to predict patients' outcomes, and also to guide the development of novel molecular therapies.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Medicina de Precisão , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/virologia , Papillomaviridae/classificação , Papillomaviridae/genética
17.
Genes (Basel) ; 15(4)2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674436

RESUMO

Glioblastoma, the most aggressive and common malignant primary brain tumour, is characterized by infiltrative growth, abundant vascularization, and aggressive clinical evolution. Patients with glioblastoma often face poor prognoses, with a median survival of approximately 15 months. Technological progress and the subsequent improvement in understanding the pathophysiology of these tumours have not translated into significant achievements in therapies or survival outcomes for patients. Progress in molecular profiling has yielded new omics data for a more refined classification of glioblastoma. Several typical genetic and epigenetic alterations in glioblastoma include mutations in genes regulating receptor tyrosine kinase (RTK)/rat sarcoma (RAS)/phosphoinositide 3-kinase (PI3K), p53, and retinoblastoma protein (RB) signalling, as well as mutation of isocitrate dehydrogenase (IDH), methylation of O6-methylguanine-DNA methyltransferase (MGMT), amplification of epidermal growth factor receptor vIII, and codeletion of 1p/19q. Certain microRNAs, such as miR-10b and miR-21, have also been identified as prognostic biomarkers. Effective treatment options for glioblastoma are limited. Surgery, radiotherapy, and alkylating agent chemotherapy remain the primary pillars of treatment. Only promoter methylation of the gene MGMT predicts the benefit from alkylating chemotherapy with temozolomide and it guides the choice of first-line treatment in elderly patients. Several targeted strategies based on tumour-intrinsic dominant signalling pathways and antigenic tumour profiles are under investigation in clinical trials. This review explores the potential genetic and epigenetic biomarkers that could be deployed as analytical tools in the diagnosis and prognostication of glioblastoma. Recent clinical advancements in treating glioblastoma are also discussed, along with the potential of liquid biopsies to advance personalized medicine in the field of glioblastoma, highlighting the challenges and promises for the future.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioblastoma/genética , Glioblastoma/terapia , Glioblastoma/patologia , Glioblastoma/tratamento farmacológico , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Biomarcadores Tumorais/genética
18.
Biomed Res Int ; 2024: 5582424, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606198

RESUMO

Glioblastoma multiforme (GBM) is the most prevalent type of brain tumour; although advancements in treatment have been made, the median survival time for GBM patients has persisted at 15 months. This study is aimed at investigating the genetic alterations and clinical features of GBM patients to find predictors of survival. GBM patients' methylation and gene expression data along with clinical information from TCGA were retrieved. The most overrepresented pathways were identified independently for each omics dataset. From the genes found in at least 30% of these pathways, one gene that was identified in both sets was further examined using the Kaplan-Meier method for survival analysis. Additionally, three groups of patients who started radio and chemotherapy at different times were identified, and the influence of these variations in treatment modality on patient survival was evaluated. Four pathways that seemed to negatively impact survival and two with the opposite effect were identified. The methylation status of PRKCB was highlighted as a potential novel biomarker for patient survival. The study also found that treatment with chemotherapy prior to radiotherapy can have a significant impact on patient survival, which could lead to improvements in clinical management and therapeutic approaches for GBM patients.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Análise de Sobrevida , Neoplasias Encefálicas/patologia , Mutação , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Prognóstico
19.
Invest Ophthalmol Vis Sci ; 65(6): 38, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38935028

RESUMO

Purpose: To assess the association of age-related macular degeneration (AMD) progression and statins, connected with AMD genetic risk, and if there is an interplay between statins and genetics. Methods: In this analysis, 682 subjects made two visits (6.5-year follow-up) of the Coimbra Eye Study. Subjects who started taking statins at any time point between the two visits were considered. Progressors were defined as not having AMD at baseline and having any AMD at follow-up. Genetic risk scores (GRSs) were calculated individually with 52 independent variants associated with AMD. Time to progression was estimated using unadjusted Kaplan-Meier curves. An extended Cox model was used for the association between statins and GRS with the risk for AMD progression. Multiplicative and additive interactions were assessed. Results: Median survival time was 7.50 years for subjects not taking statins and 7.62 for subjects taking statins (P < 0.001). Statin intake reduced the risk for progression to AMD in 48%, adjusting for age, sex, body mass index, smoking, and diabetes (model 1) and GRS (model 2). The combined effects of not taking statins and having high GRS increased the progression risk fourfold compared to taking statins and having low GRS (hazard ratio [HR] = 4.25; 95% confidence interval [CI], 1.62-11.16; P = 0.003). For subjects not taking statins, an increased risk of progression was found for those subjects with high GRS compared to subjects with low GRS (HR = 1.80; 95% CI, 1.13-2.85; P = 0.013). No statistically significant multiplicative or additive interactions were found. Conclusions: Statins seem to be protective against AMD progression, and genetics may play a role in treatment response.


Assuntos
Progressão da Doença , Inibidores de Hidroximetilglutaril-CoA Redutases , Degeneração Macular , Humanos , Masculino , Feminino , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Idoso , Degeneração Macular/genética , Seguimentos , Fatores de Risco , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença
20.
J Pers Med ; 14(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38541063

RESUMO

(1) Background: High dose gradients and manual steps in brachytherapy treatment procedures can lead to dose errors which make the use of in vivo dosimetry (IVD) highly recommended for verifying brachytherapy treatments. A new procedure was presented to obtain a calibration factor which allows fast and robust calibration of plastic scintillation detector (PSD) probes for the geometry of a compact phantom using Monte Carlo simulations. Additionally, characterization of PSD energy, angular, and temperature dependences was performed. (2) Methods: PENELOPE/PenEasy code was used to obtain the calibration factor. To characterize the energy dependence of the PSD, the signal was measured at different radial and transversal distances. The sensitivity to the angular position was characterized in axial and azimuthal planes. (3) Results: The calibration factor obtained allows for an absorbed dose to water determination in full scatter conditions from ionization measured in a mini polymethylmethacrylate (PMMA) phantom. The energy dependence of the PSD along the radial distances obtained was (2.3 ± 2.1)% (k = 1). The azimuthal angular dependence measured was (2.6 ± 3.4)% (k = 1). The PSD response decreased by (0.19 ± 0.02)%/°C with increasing detector probe temperature. (4) Conclusions: The energy, angular, and temperature dependence of a PSD is compatible with IVD.

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