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1.
Int J Mol Sci ; 22(23)2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34884678

RESUMO

Ovarian cancer (OC) is the deadliest among all gynecological cancers. Epidemiological studies showed that obesity might influence many cancers including OC. One of the key factors that may link obesity and OC is leptin (LEP), known as an adipokine with pleiotropic effects on body homeostasis. This study aims to investigate the expression pattern of LEP, assess the methylation profiles of LEP and their associations with clinicopathological features including survival outcomes of OC patients. The protein expression of LEP was evaluated in 208 samples using both tissue microarray and immunohistochemistry techniques. The methylation profiles of LEP were measured in 63 formalin-fixed, paraffin-embedded tumor tissues by quantitative polymerase chain reaction using a MethyLight assay. Our results showed a significant association of LEP protein overexpression with several clinicopathological variables, mainly tumor subtype, LVI, age of menarche, tumor size and stage (p < 0.04). Kaplan-Meier analysis (using low expression versus high expression as a discriminator) indicated that LEP protein overexpression is a powerful positive prognosticator of both OC recurrence (DFS) and disease-specific survival (DSS) in our OC cohort (log-rank p = 0.01 and p = 0.002, respectively). This implies that patients with high LEP expression profiles live longer with less recurrence rates. Methylation analysis results demonstrated a clear association between no/low LEP protein expression pattern (38%) and LEP promoter CpG island hypermethylation (43%). Results of this study suggest that LEP is a powerful prognosticator of OC recurrence and DSS. LEP expression in OC seems to be regulated by its promoter hypermethylation through gene partial/total silencing. Further multi-institutional studies using larger cohorts are required to demystify the intricate molecular functions of this leptin-driven effects in OC pathophysiology and to accurately assess its theranostic potential and validate its prognostic/predictive power in OC onset, progression towards more effective and personalized management of OC patients.


Assuntos
Leptina/metabolismo , Neoplasias Ovarianas/metabolismo , Metilação de DNA , Feminino , Humanos , Leptina/genética , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ovário/patologia , Medicina de Precisão , Prognóstico , Regiões Promotoras Genéticas , Arábia Saudita/epidemiologia
2.
Cytogenet Genome Res ; 154(1): 20-29, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29455205

RESUMO

DiGeorge syndrome (DGS) is a genetic disorder known as a clinically variable syndrome with over 180 associated phenotypic features. It is caused by a common human deletion in the 22q11.2 chromosomal region and currently is affecting approximately 1 in 4,000 individuals. Despite the prevalence of inherited diseases mainly due to consanguineous marriages, the current diagnosis of DGS in Saudi Arabia is mainly based on conventional high-resolution chromosome banding (karyotyping) and FISH techniques. However, advanced genome-wide studies for detecting microdeletions or duplications across the whole genome are needed. The aim of this study is to implement and use aCGH technology in clinical diagnosis of the 22q11.2 deletion in Saudi Arabian DGS patients and to confirm its effectiveness compared to conventional FISH and chromosome banding techniques. Thirty suspected DGS patients were assessed for chromosome 22q11.2 deletion using high-resolution G-banding, FISH, and aCGH. The aCGH results were compared with those obtained by the other 2 cytogenetic techniques. G-banding detected the 22q11.2 deletion in only 1 patient in the cohort. Moreover, it detected additional chromosomal aberrations in 3 other patients. Using FISH, allowed for detection of the 22q11.2 deletion in 2 out of 30 patients. Interestingly, the use of aCGH technique showed deletions in the chromosome 22q11.2 region in 8 patients, indicating a 4-fold increase in diagnostic detection capacity compared to FISH. Our results show the effectiveness of aCGH to overcome the limitations of FISH and G-banding in terms of diagnostic yield and allow whole genome screening and detection of a larger number of deletions and/or duplications in Saudi Arabian DGS patients. Except for balanced translocations and inversions, our data demonstrate the suitability of aCGH in the diagnostics of submicroscopic deletion syndromes such as DGS and most chromosomal aberrations or complex abnormalities scattered throughout the human genome. Our results recommend the implementation of aCGH in clinical genomic testing in Saudi Arabia to improve the diagnostic capabilities of health services while maintaining the use of conventional cytogenetic techniques for subsequent validation or for specific and known aberrations whenever required.


Assuntos
Bandeamento Cromossômico/métodos , Hibridização Genômica Comparativa/métodos , Síndrome de DiGeorge/diagnóstico , Hibridização in Situ Fluorescente/métodos , Criança , Pré-Escolar , Síndrome de DiGeorge/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Arábia Saudita , Sensibilidade e Especificidade
3.
Dev Biol ; 402(1): 61-71, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25796573

RESUMO

Klhl31 is a member of the Kelch-like family in vertebrates, which are characterized by an amino-terminal broad complex tram-track, bric-a-brac/poxvirus and zinc finger (BTB/POZ) domain, carboxy-terminal Kelch repeats and a central linker region (Back domain). In developing somites Klhl31 is highly expressed in the myotome downstream of myogenic regulators (MRF), and it remains expressed in differentiated skeletal muscle. In vivo gain- and loss-of-function approaches in chick embryos reveal a role of Klhl31 in skeletal myogenesis. Targeted mis-expression of Klhl31 led to a reduced size of dermomyotome and myotome as indicated by detection of relevant myogenic markers, Pax3, Myf5, myogenin and myosin heavy chain (MF20). The knock-down of Klhl31 in developing somites, using antisense morpholinos (MO), led to an expansion of Pax3, Myf5, MyoD and myogenin expression domains and an increase in the number of mitotic cells in the dermomyotome and myotome. The mechanism underlying this phenotype was examined using complementary approaches, which show that Klhl31 interferes with ß-catenin dependent Wnt signaling. Klhl31 reduced the Wnt-mediated activation of a luciferase reporter in cultured cells. Furthermore, Klhl31 attenuated secondary axis formation in Xenopus embryos in response to Wnt1 or ß-catenin. Klhl31 mis-expression in the developing neural tube affected its dorso-ventral patterning and led to reduced dermomyotome and myotome size. Co-transfection of a Wnt3a expression vector with Klhl31 in somites or in the neural tube rescued the phenotype and restored the size of dermomyotome and myotome. Thus, Klhl31 is a novel modulator of canonical Wnt signaling, important for vertebrate myogenesis. We propose that Klhl31 acts in the myotome to support cell cycle withdrawal and differentiation.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Proliferação de Células , Embrião de Galinha , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Hibridização In Situ , Mitose , Músculos/embriologia , Miogenina/biossíntese , Tubo Neural/metabolismo , Fenótipo , Transdução de Sinais , Somitos/metabolismo , Xenopus laevis , beta Catenina/genética
4.
BMC Genomics ; 17(Suppl 9): 750, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27766958

RESUMO

BACKGROUND: Although the primary objective of forensic DNA analyses of unidentified human remains is positive identification, cases involving historical or archaeological skeletal remains often lack reference samples for comparison. Massively parallel sequencing (MPS) offers an opportunity to provide biometric data in such cases, and these cases provide valuable data on the feasibility of applying MPS for characterization of modern forensic casework samples. In this study, MPS was used to characterize 140-year-old human skeletal remains discovered at a historical site in Deadwood, South Dakota, United States. The remains were in an unmarked grave and there were no records or other metadata available regarding the identity of the individual. Due to the high throughput of MPS, a variety of biometric markers could be typed using a single sample. RESULTS: Using MPS and suitable forensic genetic markers, more relevant information could be obtained from a limited quantity and quality sample. Results were obtained for 25/26 Y-STRs, 34/34 Y SNPs, 166/166 ancestry-informative SNPs, 24/24 phenotype-informative SNPs, 102/102 human identity SNPs, 27/29 autosomal STRs (plus amelogenin), and 4/8 X-STRs (as well as ten regions of mtDNA). The Y-chromosome (Y-STR, Y-SNP) and mtDNA profiles of the unidentified skeletal remains are consistent with the R1b and H1 haplogroups, respectively. Both of these haplogroups are the most common haplogroups in Western Europe. Ancestry-informative SNP analysis also supported European ancestry. The genetic results are consistent with anthropological findings that the remains belong to a male of European ancestry (Caucasian). Phenotype-informative SNP data provided strong support that the individual had light red hair and brown eyes. CONCLUSIONS: This study is among the first to genetically characterize historical human remains with forensic genetic marker kits specifically designed for MPS. The outcome demonstrates that substantially more genetic information can be obtained from the same initial quantities of DNA as that of current CE-based analyses.


Assuntos
Restos Mortais/metabolismo , Genética Forense/métodos , Marcadores Genéticos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Humanos , Fenótipo
5.
BMC Genomics ; 17(Suppl 9): 748, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27766947

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is characterized by the growth of a number of small cysts on the ovaries which leads to sex hormonal imbalance. Women who are affected by this syndrome suffer from irregular menstrual cycles, decline in their fertility, excessive hair growth, obesity, acne and most importantly cardiac function problems. The vascular endothelial growth factor (VEGF) plays a pivotal role in tissue vascularization in general and in the pathogenesis of many diseases. The PCOS was found to be associated with high expression levels of VEGF. In women who undergo assisted reproductive procedures (ART), VEGF was found to be a key mediator of other factors to control ovary angiogenesis. Here, we set out to examine the association of VEGFA gene polymorphism with PCOS and its components in a population of Tunisia women to enhance our understanding of the genetic background leading angiogenesis and vascularization abnormalities in PCOS. METHODS: The association of VEGFA gene with PCOS and its components was examined in a cohort of 268 women from Tunisia involving 118 PCOS patients and 150 controls. VEGFA gene variations were assessed through the analysis of the following SNPs rs699947 (A/C), rs833061 (C/T), rs1570360 (G/A), rs833068 (G/A), rs3025020 (C/T), and rs3025039 (C/T). The linkage disequilibrium between SNPs was assessed using HAPLOVIEW software while combination of SNPs into haplotypes in the population and the reconstruction of the cladogram were carried-out by PHASE and ARLEQUIN programs, respectively. Genetic association and genotype-phenotype correlations were calculated by logistic regression and non-parametric tests (Kruskall-Wallis and Mann-Whitney tests), respectively, using StatView program. RESULTS: We observed 10 haplotypes in our studied cohort whereH1 (ACGG), H2 (ACAG), H7 (CTGG) and H8 (CTGA) were the most frequent. We observed the association of the genotype CT of the SNP rs30225039 with PCOS phenotype (P = 0.03; OR 95 % CI = 2.05 [1.07-3.90]) and a trend for correlation of the pair of haplotypes H2/H2 with prolactin levels in plasma (P = 0.077; 193.5 ± 94.3 vs 45.7 ± 7.2). These data are consistent with literature and highlight one more time the role of vascularization in the pathogeny of PCOS. CONCLUSIONS: LD pattern in VEGF locus showed a similar LD pattern between the Tunisian population and the CEU. More haplotypes in the Tunisian population than in CEU was observed (22 haplotypes vs 16 haplotypes) suggesting higher recombination rate in Tunisians. The study showed that there was any advantage of using haplotypes compared with SNPs taken alone.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Síndrome do Ovário Policístico/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Alelos , Biomarcadores , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Fenótipo , Síndrome do Ovário Policístico/diagnóstico , Polimorfismo de Nucleotídeo Único , Prevalência , Fatores de Risco , Tunísia
6.
BMC Genomics ; 17(Suppl 9): 747, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27766952

RESUMO

The Third International Genomic Medicine Conference (3rd IGMC) was organised by the Centre of Excellence in Genomic Medicine Research (CEGMR) at the King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia (KSA). This conference is a continuation of a series of meetings, which began with the first International Genomic Medicine Conference (1st IGMC, 2011) followed by the second International Genomic Medicine Conference (2nd IGMC, 2013). The 3rd IGMC meeting presented as a timely opportunity to bring scientists from across the world to gather, discuss, and exchange recent advances in the field of genomics and genetics in general as well as practical information on using these new technologies in different basic and clinical applications. The meeting undoubtedly inspired young male and female Saudi researchers, who attended the conference in large numbers, as evidenced by the oversubscribed oral and poster presentations. The conference also witnessed the launch of the first content for npj Genomic Medicine, a high quality new journal was established in partnership by CEGMR with Springer Nature and published as part of the Nature Partner Journal series. Here, we present a brief summary report of the 2-day meeting including highlights from the oral presentations, poster presentations, workshops, poster prize-winners and comments from the distinguished scientists.


Assuntos
Genômica , Medicina , Biologia Computacional/métodos , Predisposição Genética para Doença , Genômica/métodos , Humanos , Medicina/métodos
7.
BMC Struct Biol ; 16(Suppl 1): 16, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27719669

RESUMO

BACKGROUND: Di-(2-ethylhexyl)phthalate (DEHP) is a common endocrine disrupting compound (EDC) present in the environment as a result of industrial activity and leaching from polyvinyl products. DEHP is used as a plasticizer in medical devices and many commercial and household items. Exposure occurs through inhalation, ingestion, and skin contact. DEHP is metabolized to a primary metabolite mono-(2-ethylhexyl)phthalate (MEHP) in the body, which is further metabolized to four major secondary metabolites, mono(2-ethyl-5-hydroxyhexyl)phthalate (5-OH-MEHP), mono(2-ethyl-5-oxyhexyl)phthalate (5-oxo-MEHP), mono(2-ethyl-5-carboxypentyl)phthalate (5-cx-MEPP) and mono[2-(carboxymethyl)hexyl]phthalate (2-cx-MMHP). DEHP and its metabolites are associated with developmental abnormalities and reproductive dysfunction within the human population. Progesterone receptor (PR) signaling is involved in important reproductive functions and is a potential target for endocrine disrupting activities of DEHP and its metabolites. This study used in silico approaches for structural binding analyses of DEHP and its five indicated major metabolites with PR. METHODS: Protein Data bank was searched to retrieve the crystal structure of human PR (Id: 1SQN). PubChem database was used to obtain the structures of DEHP and its five metabolites. Docking was performed using Glide (Schrodinger) Induced Fit Docking module. RESULTS: DEHP and its metabolites interacted with 19-25 residues of PR with the majority of the interacting residues overlapping (82-95 % commonality) with the native bound ligand norethindrone (NET). DEHP and each of its five metabolites formed a hydrogen bonding interaction with residue Gln-725 of PR. The binding affinity was highest for NET followed by DEHP, 5-OH-MEHP, 5-oxo-MEHP, MEHP, 5-cx-MEPP, and 2-cx-MMHP. CONCLUSION: The high binding affinity of DEHP and its five major metabolites with PR as well as a high rate of overlap between PR interacting residues among DEHP and its metabolites and the native ligand, NET, suggested their disrupting potential in normal PR signaling, resulting in adverse reproductive effects.


Assuntos
Dietilexilftalato/metabolismo , Disruptores Endócrinos/metabolismo , Plastificantes/metabolismo , Receptores de Progesterona/metabolismo , Dietilexilftalato/análogos & derivados , Dietilexilftalato/química , Disruptores Endócrinos/química , Humanos , Simulação de Acoplamento Molecular , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Plastificantes/química , Ligação Proteica , Receptores de Progesterona/química
8.
BMC Struct Biol ; 16(Suppl 1): 15, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27719672

RESUMO

BACKGROUND: Currently, alternate plasticizers are used to replace phthalate plasticizers in children's toys, medical equipments and food packaging, due to the adverse effects of phthalate compounds on human health and laws prohibiting their use. Current information regarding the safety and potential adverse effects of alternate plasticizers is limited and recent studies have found alternate plasticizers to display similar characteristics to those observed in phthalate plasticizers. This study was undertaken to evaluate and predict the potential endocrine disrupting activity of the three most commonly used alternate plasticizers: di(2-ethylhexyl)terephthalate (DEHT), tris(2-ethylhexyl)trimellitate (TOTM), and diisononyl hexahydrophthalate (DINCH) against human sex hormone-binding globulin (SHBG) using in silico approaches. MATERIALS AND METHODS: The crystal structure of human SHBG (Id: 1D2S) was retrieved from Protein Data Bank. PubChem database was searched for the structures of alternate plasticizers, DEHT, TOTM, and DINCH. Docking was performed using Glide (Schrodinger) Induced Fit Docking module. RESULTS: Induced Fit Docking of three alternate plasticizer compounds indicated that each of the three compounds fitted well into the steroid binding pocket of SHBG. Docking displays showed interactions of alternate plasticizers with 25-30 amino-acid residues of SHBG; 18-20 amino residues overlapped between the natural ligand, DHT, and the three compounds (commonality of 82-91 %). The hydrogen-bonding interaction of the amino-acid residue, Asn-82, of SHBG was also present in displays of DHT and all the three alternate phthalates. The binding affinity of all the three alternate phthalates was higher than DHT; maximum in DINCH followed by TOTM and DEHT. CONCLUSION: Our results suggested that the three alternate plasticizers have potential to engage the important interacting residues of SHBG and thus interfere in its steroid homeostatic function.


Assuntos
Benzoatos/metabolismo , Ácidos Ftálicos/metabolismo , Plastificantes/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo , Benzoatos/química , Humanos , Simulação de Acoplamento Molecular , Ácidos Ftálicos/química , Plastificantes/química , Ligação Proteica , Globulina de Ligação a Hormônio Sexual/química
9.
BMC Med Genet ; 17(Suppl 1): 68, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27766954

RESUMO

BACKGROUND: Osteoarthritis (OA) is a progressive joint disease characterized by gradual degradation of extracellular matrix (ECM) components in the cartilage and bone. The ECM of cartilage is a highly specified structure that is mainly composed of type II collagen and provides tensile strength to the tissue via aggrecan and proteoglycans. However, changes in the ECM composition and structure can lead to loss of collagen type II and network integrity. Several risk factors have been correlated with OA including age, genetic predisposition, hereditary factors, obesity, mechanical injuries, and joint trauma. Certain genetic association studies have identified several genes associated with OA using genome-wide association studies (GWASs). RESULTS: We identified several novel genetic variants affecting genes that function in several candidate causative pathways including immune responses, inflammatory and cartilage degradation such as SELP, SPN, and COL6A6. CONCLUSIONS: The approach of whole-exome sequencing can be a promising method to identify genetic mutations that can influence the OA disease.


Assuntos
Exoma/genética , Variação Genética , Osteoartrite/genética , Idoso , Cartilagem/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo VI/genética , Estudo de Associação Genômica Ampla , Humanos , Leucossialina/genética , Pessoa de Meia-Idade , Osteoartrite/patologia , Selectina-P/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco
10.
BMC Med Genet ; 17(Suppl 1): 69, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27766963

RESUMO

BACKGROUND: Recurrent pregnancy loss (RPL) or recurrent spontaneous abortion is an obstetric complication that affects couples at reproductive age. Previous reports documented a clear relationship between parents with chromosomal abnormalities and both recurrent miscarriages and infertility. However, limited data is available from the Arabian Peninsula which is known by higher rates of consanguineous marriages. The main goal of this study was to determine the prevalence of chromosomal abnormalities and thrombophilic polymorphisms, and to correlate them with RPL and consanguinity in Saudi Arabia. METHODS: Cytogenetic analysis of 171 consent patients with RPL was performed by the standard method of 72-h lymphocyte culture and GTG banding. Allelic polymorphisms of three thrombophilic genes (Factor V Leiden, Prothrombin A20210G, MTHFR C677T) were performed using PCR-RFLP (restriction fragment length polymorphism) and gel electrophoresis. RESULTS: Data analysis revealed that 7.6 % of patients were carrier of numerical or structural chromosomal abnormalities. A high rate of translocations (46 %) was associated to increased incidence of RPL. A significant correlation between consanguineous RPL patients and chromosomal abnormalities (P < 0.05) was found. Both Factor V Leiden and Prothrombin A20210G allelic polymorphisms were significantly associated with a higher prevalence of RPL. CONCLUSIONS: This study demonstrated a strong association between RPL and the prevalence of chromosomal abnormalities and inherited thrombophilia. Given the high rate of consanguineous marriages in the Saudi population, these results underline the importance of systematic cytogenetic investigation and genetic counseling preferably at the premarital stage or at least during early pregnancy phase through preimplantation genetic diagnosis (PGD).


Assuntos
Aborto Habitual/etiologia , Aborto Habitual/genética , Aberrações Cromossômicas , Consanguinidade , Trombofilia/complicações , Trombofilia/genética , Adolescente , Adulto , Alelos , Fator V/genética , Feminino , Humanos , Linfócitos/citologia , Linfócitos/metabolismo , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Polimorfismo Genético , Gravidez , Protrombina/genética , Fatores de Risco , Arábia Saudita , Trombofilia/diagnóstico , Translocação Genética , Adulto Jovem
11.
BMC Genomics ; 16 Suppl 1: S12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25923536

RESUMO

BACKGROUND: We report a consanguineous couple that has experienced three consecutive pregnancy losses following the foetal ultrasound finding of short limbs. Post-termination examination revealed no skeletal dysplasia, but some subtle proximal limb shortening in two foetuses, and a spectrum of mildly dysmorphic features. Karyotype was normal in all three foetuses (46, XX) and comparative genomic hybridization microarray analysis detected no pathogenic copy number variants. RESULTS: Whole-exome sequencing and genome-wide homozygosity mapping revealed a previously reported frameshift mutation in the OBSL1 gene (c.1273insA p.T425nfsX40), consistent with a diagnosis of 3-M Syndrome 2 (OMIM #612921), which had not been anticipated from the clinical findings. CONCLUSIONS: Our study provides novel insight into the early clinical manifestations of this form of 3-M syndrome, and demonstrates the utility of whole exome sequencing as a tool for prenatal diagnosis in particular when there is a family history suggestive of a recurrent set of clinical symptoms.


Assuntos
Autopsia , Proteínas do Citoesqueleto/genética , Nanismo/diagnóstico , Nanismo/genética , Feto/metabolismo , Mutação da Fase de Leitura/genética , Hipotonia Muscular/diagnóstico , Hipotonia Muscular/genética , Coluna Vertebral/anormalidades , Análise Mutacional de DNA , Exoma , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Gravidez
12.
Tumour Biol ; 36(12): 9677-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26152288

RESUMO

Invasive ductal carcinoma of the breast is the most common cancer affecting women worldwide. The marked heterogeneity of breast cancer is matched only with the heterogeneity in its associated or causative factors. Breast cancer in Saudi Arabia is apparently an early onset with many of the affected females diagnosed before they reach the age of 50 years. One possible rationale underlying this observation is that consanguinity, which is widely spread in the Saudi community, is causing the accumulation of yet undetermined cancer susceptibility mutations. Another factor could be the accumulation of epigenetic aberrations caused by the shift toward a Western-like lifestyle in the past two decades. In order to shed some light into the molecular mechanisms underlying breast cancer in the Saudi community, we identified KLOTHO (KL) as a tumor-specific methylated gene using genome-wide methylation analysis of primary breast tumors utilizing the MBD-seq approach. KL methylation was frequent as it was detected in 55.3 % of breast cancer cases from Saudi Arabia (n = 179) using MethyLight assay. Furthermore, KL is downregulated in breast tumors with its expression induced following treatment with 5-azacytidine. The involvement of KL in breast cancer led us to investigate its relationship in the context of breast cancer, with one of the protagonists of its function, fibroblast growth factor receptor 4 (FGFR4). Overexpression of FGFR4 in breast cancer is frequent in our cohort and this overexpression is associated with poor overall survival. Interestingly, FGFR4 expression is higher in the absence of KL methylation and lower when KL is methylated and presumably silenced, which is suggestive of an intricate relationship between the two factors. In conclusion, our findings further implicate "metabolic" genes or pathways in breast cancer that are disrupted by epigenetic mechanisms and could provide new avenues for understanding this disease in a new context.


Assuntos
Carcinoma Ductal de Mama/genética , Fatores de Crescimento de Fibroblastos/biossíntese , Glucuronidase/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal de Mama/patologia , Linhagem Celular Tumoral , Ilhas de CpG , Metilação de DNA/genética , Epigênese Genética , Feminino , Fatores de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Klotho , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética
13.
Reprod Biol Endocrinol ; 13: 35, 2015 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-25928123

RESUMO

Over the last decade, there has been a significant increase in average paternal age when the first child is conceived, either due to increased life expectancy, widespread use of contraception, late marriages and other factors. While the effect of maternal ageing on fertilization and reproduction is well known and several studies have shown that women over 35 years have a higher risk of infertility, pregnancy complications, spontaneous abortion, congenital anomalies, and perinatal complications. The effect of paternal age on semen quality and reproductive function is controversial for several reasons. First, there is no universal definition for advanced paternal ageing. Secondly, the literature is full of studies with conflicting results, especially for the most common parameters tested. Advancing paternal age also has been associated with increased risk of genetic disease. Our exhaustive literature review has demonstrated negative effects on sperm quality and testicular functions with increasing paternal age. Epigenetics changes, DNA mutations along with chromosomal aneuploidies have been associated with increasing paternal age. In addition to increased risk of male infertility, paternal age has also been demonstrated to impact reproductive and fertility outcomes including a decrease in IVF/ICSI success rate and increasing rate of preterm birth. Increasing paternal age has shown to increase the incidence of different types of disorders like autism, schizophrenia, bipolar disorders, and childhood leukemia in the progeny. It is thereby essential to educate the infertile couples on the disturbing links between increased paternal age and rising disorders in their offspring, to better counsel them during their reproductive years.


Assuntos
Envelhecimento/genética , Idade Paterna , Reprodução/genética , Análise do Sêmen , Fatores Etários , Epigênese Genética , Feminino , Estudo de Associação Genômica Ampla , Instabilidade Genômica , Humanos , Masculino , Transtornos Mentais/genética , Gravidez , Resultado da Gravidez , Medição de Risco , Encurtamento do Telômero
14.
BMC Cancer ; 15 Suppl 1: S2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25708621

RESUMO

BACKGROUND: Adult T-cell Leukemia (ATL) is a disease with no known cure. The disease manifests itself as an aggressive proliferation of CD4+ cells with the human T-cell Lymphotropic virus type 1 (HTLV-1). The leukemogenesis of the virus is mainly attributed to the viral oncoprotein. Tax activates the Nuclear Factor kappa B (NF-κB) which stimulates the activity and expression of the matrix metalloproteinase-9 (MMP-9). The objective of this study was to investigate the efficacy of a specific nutrient synergy (SNS) on proliferation, Tax expression, NF-κB levels as well as on MMP-9 activity and expression both at the transcriptional and translational levels in two HTLV-1 positive cell lines, HuT-102 and C91-PL at 48h and 96h of incubation. Cytotoxicity of Epigallocatechin-3-gallate (EGCG) was assayed using CytoTox 96 Non-radioactive and proliferation was measured using Cell Titer96TM Nonradioactive Cell Proliferation kit (MTT- based assay). Enzyme linked immunosorbant assay (ELISA) and electrophoretic mobility shift assay (EMSA) were used to assess the effect of SNS on NF-κB mobility. Zymography was used to determine the effects of SNS on the activity and secretion of MMP-9. The expression of MMP-9 was done using RT-PCR at the translational level and Immunoblotting at the transcriptional level. RESULTS: A significant inhibition of proliferation was seen in both cell lines starting at a concentration of 200µg/ml and in a dose dependent manner. SNS induced a dose dependent decrease in Tax expression, which was paralleled by a down-regulation of the nuclearization of NF-κB. This culminated in the inhibition of the activity of MMP-9 and their expression both at the transcriptional and translational levels. CONCLUSIONS: The results of this study indicate that a specific nutrient synergy targeted multiple levels pertinent to the progression of ATL. Its activity was mediated through the NF-κB pathway, and hence has the potential to be integrated in the treatment of this disease as a natural potent anticancer agent.


Assuntos
Anticarcinógenos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Catequina/análogos & derivados , Núcleo Celular/metabolismo , Produtos do Gene tax/metabolismo , Infecções por HTLV-I/tratamento farmacológico , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Leucemia-Linfoma de Células T do Adulto/prevenção & controle , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Carcinogênese/efeitos dos fármacos , Catequina/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Produtos do Gene tax/genética , Infecções por HTLV-I/complicações , Infecções por HTLV-I/imunologia , Humanos , Leucemia-Linfoma de Células T do Adulto/etiologia , Leucemia-Linfoma de Células T do Adulto/imunologia , Metaloproteinase 9 da Matriz/genética , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
15.
Tumour Biol ; 35(3): 2817-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24248542

RESUMO

Metabolic diseases like diabetes and obesity are major risk factors for breast cancer. Aberrant expression of metabolic effectors such as fibroblast growth factor 19 (FGF19) could be therefore associated with the disease. The expression of FGF19 was examined in 193 archival breast tumor samples by immunohistochemistry and evaluated semi-quantitatively by determining the staining index and correlating it with clinicopathological parameters using Fisher's exact test. The correlation between FGF19 expression and 5-year disease-specific survival rate was determined using the univariate Kaplan-Meier analysis. The prognostic value of FGF19 expression was evaluated using the multivariate Cox regression analysis. Of the 193 tumors analyzed, 40% were classified with low FGF19 expression, whereas 60% were categorized as tumors with high FGF19 expression. There was a highly significant correlation between high FGF19 expression and patients' age (p = 0.008) as well as 5-year disease-specific survival (p = 0.001). However, FGF19 expression did not show any significant correlations with other clinicopathological parameters, including hormonal status, tumor grade, tumor size, or lymph node status. Univariate Kaplan-Meier log rank analysis showed that patients with high FGF19 expression exhibited a significantly shorter disease-specific 5-year survival (p = 0.007). This effect was exacerbated by lymph node metastasis (p = 0.001), negative estrogen receptor (ER) status (p = 0.002), or old age (p = 0.013). Multivariate analysis showed that high FGF19 expression could be an independent prognostic marker of disease-specific survival in breast cancer patients (p = 0.030). Quantification of FGF19 expression appears to provide valuable prognostic information in breast cancer, particularly in older patients with lymph node metastasis and negative ER status.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/mortalidade , Fatores de Crescimento de Fibroblastos/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Fatores de Crescimento de Fibroblastos/análise , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Receptores de Estrogênio/análise , Receptores de Estrogênio/metabolismo
16.
Reprod Biol Endocrinol ; 12: 121, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25466430

RESUMO

BACKGROUND: Density gradient is the preferred technique for sperm processing for ART. However, no study has examined sperm quality using different processing media simultaneously and under identical conditions. Therefore, we evaluated semen quality following sperm preparation by three commonly used commercially available density gradient media in a well-designed controlled trial. METHODS: We obtained semen samples from 20 healthy volunteers. Percent motility, total motile sperm (TMS), % recovery and DNA damage were assessed before and after separation in three different sperm density gradient media-PureCeption, ISolate and SpermGrad-125. RESULTS: Percent motility was higher in the ISolate (81.4% ± 6.6%) and SpermGrad-125 samples (85.7% ± 8.0%) (P < 0.0001) than in the PureCeption samples (62.5% ± 13.2%) (P = 0.07). TMS was higher in the PureCeption(TM) and ISolate samples (14.2% ± 15.9% and 15.8% ± 18.2%) than in those prepared with SpermGrad-125 (10.6% ± 19.7%) (P < 0.0001). Percent recovery was significantly higher in the PureCeption(TM) and ISolate samples (45.3% and 48.9%) than in the SpermGrad-125(TM) samples (30.8%) (P < 0.01). DNA fragmentation was comparable across the three gradients (PureCeption = 8.8% ± 4.7%; ISolate = 7.2 ± 5.2% and SpermGrad-125 = 11.2% ± 7.4%). CONCLUSIONS: Three different density gradient processing media PureCeption, ISolate, and SpermGrad-125 were examined for their effects on sperm quality. Sperm processed by ISolate and Sperm Grad 125 had better motility and TMS after processing. The extent of DNA damage was comparable in all three gradients.


Assuntos
Centrifugação com Gradiente de Concentração/métodos , Análise do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Adulto , Separação Celular/métodos , Dano ao DNA , Citometria de Fluxo , Humanos , Masculino , Contagem de Espermatozoides , Espermatozoides/citologia , Espermatozoides/metabolismo , Adulto Jovem
17.
Proc Natl Acad Sci U S A ; 108(29): 11936-41, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-21730146

RESUMO

Commitment of progenitors in the dermomyotome to myoblast fate is the first step in establishing the body musculature. Pax3 is a crucial transcription factor, important for skeletal muscle development and expressed in myogenic progenitors in the dermomyotome of developing somites and in migratory muscle progenitors that populate the limb buds. Down-regulation of Pax3 is essential to ignite the myogenic program, including up-regulation of myogenic regulators, Myf-5 and MyoD. MicroRNAs (miRNAs) confer robustness to developmental timing by posttranscriptional repression of genetic programs that are related to previous developmental stages or to alternative cell fates. Here we demonstrate that the muscle-specific miRNAs miR-1 and miR-206 directly target Pax3. Antagomir-mediated inhibition of miR-1/miR-206 led to delayed myogenic differentiation in developing somites, as shown by transient loss of myogenin expression. This correlated with increased Pax3 and was phenocopied using Pax3-specific target protectors. Loss of myogenin after antagomir injection was rescued by Pax3 knockdown using a splice morpholino, suggesting that miR-1/miR-206 control somite myogenesis primarily through interactions with Pax3. Our studies reveal an important role for miR-1/miR-206 in providing precision to the timing of somite myogenesis. We propose that posttranscriptional control of Pax3 downstream of miR-1/miR-206 is required to stabilize myoblast commitment and subsequent differentiation. Given that mutually exclusive expression of miRNAs and their targets is a prevailing theme in development, our findings suggest that miRNA may provide a general mechanism for the unequivocal commitment underlying stem cell differentiation.


Assuntos
Diferenciação Celular/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , MicroRNAs/metabolismo , Desenvolvimento Muscular/fisiologia , Fatores de Transcrição Box Pareados/metabolismo , Animais , Western Blotting , Diferenciação Celular/genética , Células Cultivadas , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Técnicas de Introdução de Genes , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Desenvolvimento Muscular/genética , Miogenina/metabolismo , Oligonucleotídeos/administração & dosagem , Oligonucleotídeos/genética , Fator de Transcrição PAX3 , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease III/genética , Ribonuclease III/metabolismo
18.
Arthritis Rheum ; 64(6): 1909-19, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22143896

RESUMO

OBJECTIVE: To use an in vitro model of chondrogenesis to identify microRNAs (miRNAs) with a functional role in cartilage homeostasis. METHODS: The expression of miRNAs was measured in the ATDC5 cell model of chondrogenesis using microarray and was verified using quantitative reverse transcription-polymerase chain reaction. MicroRNA expression was localized by in situ hybridization. Predicted miRNA target genes were validated using 3'-untranslated region-Luc reporter plasmids containing either wild-type sequences or mutants of the miRNA target sequence. Signaling through the Smad pathway was measured using a (CAGA)(12) -Luc reporter. RESULTS: The expression of several miRNAs was regulated during chondrogenesis. These included 39 miRNAs that are coexpressed with miRNA-140 (miR-140), which is known to be involved in cartilage homeostasis and osteoarthritis (OA). Of these miRNAs, miR-455 resides within an intron of COL27A1 that encodes a cartilage collagen. When human OA cartilage was compared with cartilage obtained from patients with femoral neck fractures, the expression of both miR-140-5p and miR-455-3p was increased in OA cartilage. In situ hybridization showed miR-455-3p expression in the developing limbs of chicks and mice and in human OA cartilage. The expression of miR-455-3p was regulated by transforming growth factor ß (TGFß) ligands, and miRNA regulated TGFß signaling. ACVR2B, SMAD2, and CHRDL1 were direct targets of miR-455-3p and may mediate its functional impact on TGFß signaling. CONCLUSION: MicroRNA-455 is expressed during chondrogenesis and in adult articular cartilage, where it can regulate TGFß signaling, suppressing the Smad2/3 pathway. Diminished signaling through this pathway during the aging process and in OA chondrocytes is known to contribute to cartilage destruction. We propose that the increased expression of miR-455 in OA exacerbates this process and contributes to disease pathology.


Assuntos
Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Condrogênese/fisiologia , Articulação do Quadril/metabolismo , MicroRNAs/metabolismo , Osteoartrite do Quadril/metabolismo , Células 3T3 , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Cartilagem Articular/patologia , Células Cultivadas , Condrócitos/patologia , Feminino , Articulação do Quadril/patologia , Humanos , Masculino , Camundongos , MicroRNAs/genética , Pessoa de Meia-Idade , Osteoartrite do Quadril/genética , Osteoartrite do Quadril/patologia
19.
Oncol Lett ; 26(5): 477, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37809047

RESUMO

Breast cancer (BC) is one of the most widespread types of cancer affecting females, and therefore, early diagnosis is critical. BC is a complex heterogeneous disease affected by several key pathways. Among these, WNT proteins and their frizzled receptors (FZD) have been demonstrated to be crucial in regulating a number of cellular and molecular events in BC tumorigenesis. The role of the WNT receptor, FZD8, in BC has received minimal attention; for that reason, the present study examined the prognostic value of its protein expression pattern in a BC cohort. FZD8 cytoplasmic expression pattern analysis revealed that ~38% of the primary samples presented with a high expression profile, whereas ~63% of the samples had a low expression profile. Overall, ~46% of the malignant tissues in the lymph node-positive samples exhibited an increased FZD8 cytoplasmic expression, whereas 54% exhibited low expression levels. An increased expression of FZD8 was associated with several clinicopathological characteristics of the patients, including a low survival rate, tumor vascular invasion, tumor size and grade, and molecular subtypes. Affymetrix microarray triple-negative BC datasets were analyzed and compared with healthy breast tissues in order to predict the potential interfering microRNAs (miRNAs) in the WNT/FZD8 signaling pathway. A total of 29 miRNAs with the potential to interact with the WNT/FZD8 signaling pathway were identified, eight of which exhibited a significant prediction score. The target genes for each predicted miRNA were identified. On the whole, the findings of the present study suggest that FZD8 is a potential prognostic marker for BC, shedding some light onto the silencing mechanisms involved in the complex BC signaling.

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