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1.
Nature ; 615(7954): 866-873, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36991187

RESUMO

The urban peoples of the Swahili coast traded across eastern Africa and the Indian Ocean and were among the first practitioners of Islam among sub-Saharan people1,2. The extent to which these early interactions between Africans and non-Africans were accompanied by genetic exchange remains unknown. Here we report ancient DNA data for 80 individuals from 6 medieval and early modern (AD 1250-1800) coastal towns and an inland town after AD 1650. More than half of the DNA of many of the individuals from coastal towns originates from primarily female ancestors from Africa, with a large proportion-and occasionally more than half-of the DNA coming from Asian ancestors. The Asian ancestry includes components associated with Persia and India, with 80-90% of the Asian DNA originating from Persian men. Peoples of African and Asian origins began to mix by about AD 1000, coinciding with the large-scale adoption of Islam. Before about AD 1500, the Southwest Asian ancestry was mainly Persian-related, consistent with the narrative of the Kilwa Chronicle, the oldest history told by people of the Swahili coast3. After this time, the sources of DNA became increasingly Arabian, consistent with evidence of growing interactions with southern Arabia4. Subsequent interactions with Asian and African people further changed the ancestry of present-day people of the Swahili coast in relation to the medieval individuals whose DNA we sequenced.


Assuntos
População Africana , Asiático , Genética Populacional , Feminino , Humanos , Masculino , População Africana/genética , Asiático/genética , História Medieval , Oceano Índico , Tanzânia , Quênia , Moçambique , Comores , História do Século XV , História do Século XVI , História do Século XVII , Índia/etnologia , Pérsia/etnologia , Arábia/etnologia , DNA Antigo/análise
2.
J Immunol ; 211(11): 1736-1746, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37861348

RESUMO

Cancer chemotherapy-induced neuropathic pain is a devastating pain syndrome without effective therapies. We previously reported that rats deficient in complement C3, the central component of complement activation cascade, showed a reduced degree of paclitaxel-induced mechanical allodynia (PIMA), suggesting that complement is integrally involved in the pathogenesis of this model. However, the underlying mechanism was unclear. Complement activation leads to the production of C3a, which mediates inflammation through its receptor C3aR1. In this article, we report that the administration of paclitaxel induced a significantly higher expression level of C3aR1 on dorsal root ganglion (DRG) macrophages and expansion of these macrophages in DRGs in wild-type (WT) compared with in C3aR1 knockout (KO) mice. We also found that paclitaxel induced less severe PIMA, along with a reduced DRG expression of transient receptor potential channels of the vanilloid subtype 4 (TRPV4), an essential mediator for PIMA, in C3aR1 KO than in WT mice. Treating WT mice or rats with a C3aR1 antagonist markedly attenuated PIMA in association with downregulated DRG TRPV4 expression, reduced DRG macrophages expansion, suppressed DRG neuron hyperexcitability, and alleviated peripheral intraepidermal nerve fiber loss. Administration of C3aR1 antagonist to TRPV4 KO mice further protected them from PIMA. These results suggest that complement regulates PIMA development through C3aR1 to upregulate TRPV4 on DRG neurons and promote DRG macrophage expansion. Targeting C3aR1 could be a novel therapeutic approach to alleviate this debilitating pain syndrome.


Assuntos
Neuralgia , Paclitaxel , Ratos , Camundongos , Animais , Paclitaxel/efeitos adversos , Canais de Cátion TRPV/genética , Iodeto de Potássio/efeitos adversos , Iodeto de Potássio/metabolismo , Ratos Sprague-Dawley , Neuralgia/induzido quimicamente , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Proteínas do Sistema Complemento/metabolismo , Receptores de Complemento/genética , Receptores de Complemento/metabolismo
3.
J Med Genet ; 55(2): 122-130, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29122926

RESUMO

BACKGROUND: Bone dysplasias are a large group of disorders affecting the growth and structure of the skeletal system. METHODS: In the present study, we report the clinical and molecular delineation of a new form of syndromic autosomal recessive spondylometaphyseal dysplasia (SMD) in two Emirati first cousins. They displayed postnatal growth deficiency causing profound limb shortening with proximal and distal segments involvement, narrow chest, radiological abnormalities involving the spine, pelvis and metaphyses, corneal clouding and intellectual disability. Whole genome homozygosity mapping localised the genetic cause to 11q12.1-q13.1, a region spanning 19.32 Mb with ~490 genes. Using whole exome sequencing, we identified four novel homozygous variants within the shared block of homozygosity. Pathogenic variants in genes involved in phospholipid metabolism, such as PLCB4 and PCYT1A, are known to cause bone dysplasia with or without eye anomalies, which led us to select PLCB3 as a strong candidate. This gene encodes phospholipase C ß 3, an enzyme that converts phosphatidylinositol 4,5 bisphosphate (PIP2) to inositol 1,4,5 triphosphate (IP3) and diacylglycerol. RESULTS: The identified variant (c.2632G>T) substitutes a serine for a highly conserved alanine within the Ha2' element of the proximal C-terminal domain. This disrupts binding of the Ha2' element to the catalytic core and destabilises PLCB3. Here we show that this hypomorphic variant leads to elevated levels of PIP2 in patient fibroblasts, causing disorganisation of the F-actin cytoskeleton. CONCLUSIONS: Our results connect a homozygous loss of function variant in PLCB3 with a new SMD associated with corneal dystrophy and developmental delay (SMDCD).


Assuntos
Distrofias Hereditárias da Córnea/genética , Osteocondrodisplasias/genética , Fosfatidilinositóis/metabolismo , Fosfolipase C beta/genética , Substituição de Aminoácidos , Criança , Pré-Escolar , Cromossomos Humanos Par 11 , Distrofias Hereditárias da Córnea/etiologia , Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/genética , Feminino , Homozigoto , Humanos , Recém-Nascido , Deficiência Intelectual/genética , Masculino , Osteocondrodisplasias/etiologia , Linhagem , Fosfatidilinositóis/genética , Fosfolipase C beta/metabolismo , Transdução de Sinais/genética
4.
BMC Med Genet ; 19(1): 34, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499638

RESUMO

BACKGROUND: Congenital hydrocephalus (CH) results from the accumulation of excessive amounts of cerebrospinal fluid (CSF) in the brain, often leading to severe neurological impairments. However, the adverse effects of CH can be reduced if the condition is detected and treated early. Earlier reports demonstrated that some CH cases are caused by mutations in L1CAM gene encoding the neural cell adhesion molecule L1. On the other hand, recent studies have implicated the multiple PDZ domain (MPDZ) gene in some severe forms of CH, inherited in an autosomal recessive pattern. METHODS: In this study, whole-exome and Sanger sequencing were performed on a 9 months old Emirati child clinically diagnosed by CH. In addition, in silico, cellular, and molecular assays have been conducted to confirm pathogenicity of the identified variants and to establish disease mechanism. RESULTS: Whole exome sequencing revealed two compound heterozygous novel variants (c.394G > A and c.1744C > G) in the affected child within the MPDZ gene. Segregation analysis revealed that each of the parents is heterozygous for one of the two variants and therefore passed that variant to their child. The outcome of the in silico and bioinformatics analyses came in line with the experimental data, suggesting that the two variants are most likely disease causing. CONCLUSIONS: The compound heterozygous variants identified in this study are the most likely cause of CH in the affected child. The study further confirms MPDZ as a gene underlying some CH cases.


Assuntos
Heterozigoto , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/genética , Molécula L1 de Adesão de Célula Nervosa/genética , Domínios PDZ/genética , Sequência de Aminoácidos , Encéfalo/metabolismo , Adesão Celular , Genes Recessivos , Variação Genética , Células HEK293 , Células HeLa , Humanos , Lactente , Masculino , Mutação , Neurônios/citologia , Neurônios/efeitos dos fármacos , Linhagem , Conformação Proteica , Análise de Sequência de DNA , Sequenciamento do Exoma
5.
Hum Mol Genet ; 23(13): 3456-66, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24501276

RESUMO

Whereas many genes associated with intellectual disability (ID) encode synaptic proteins, transcriptional defects leading to ID are less well understood. We studied a large, consanguineous pedigree of Arab origin with seven members affected with ID and mild dysmorphic features. Homozygosity mapping and linkage analysis identified a candidate region on chromosome 17 with a maximum multipoint logarithm of odds score of 6.01. Targeted high-throughput sequencing of the exons in the candidate region identified a homozygous 4-bp deletion (c.169_172delCACT) in the METTL23 (methyltransferase like 23) gene, which is predicted to result in a frameshift and premature truncation (p.His57Valfs*11). Overexpressed METTL23 protein localized to both nucleus and cytoplasm, and physically interacted with GABPA (GA-binding protein transcription factor, alpha subunit). GABP, of which GABPA is a component, is known to regulate the expression of genes such as THPO (thrombopoietin) and ATP5B (ATP synthase, H+ transporting, mitochondrial F1 complex, beta polypeptide) and is implicated in a wide variety of important cellular functions. Overexpression of METTL23 resulted in increased transcriptional activity at the THPO promoter, whereas knockdown of METTL23 with siRNA resulted in decreased expression of ATP5B, thus revealing the importance of METTL23 as a regulator of GABPA function. The METTL23 mutation highlights a new transcriptional pathway underlying human intellectual function.


Assuntos
Metilases de Modificação do DNA/metabolismo , Fator de Transcrição de Proteínas de Ligação GA/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Metilases de Modificação do DNA/genética , Feminino , Fator de Transcrição de Proteínas de Ligação GA/genética , Genótipo , Humanos , Imunoprecipitação , Masculino , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica , RNA Interferente Pequeno , Trombopoetina/genética , Trombopoetina/metabolismo , Técnicas do Sistema de Duplo-Híbrido
6.
Am J Med Genet A ; 170(8): 2111-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27183861

RESUMO

Clinical classification of overgrowth syndromes represents a challenge since a wide spectrum of disorders result in marked overgrowth. Therefore, there is a continuous effort to identify the genetic basis of these disorders that will eventually facilitate their molecular classification. Here, we have identified the genetic etiology and the pathogenetic mechanism underlying a rare autosomal recessive overgrowth syndrome in three affected siblings. The overgrowth phenotype in the patients was accompanied by developmental delay, learning disabilities, and variable congenital abnormalities. To elucidate the genetic etiology of the disorder, whole-genome genotyping and whole-exome sequencing were used. The disease was mapped to 3p21.1-p14.2 and 11q13.1-q13.4, where an in-frame insertion (c.175_176insTAA) in FIBP gene was revealed. The resulting indel (p.H59LN) was predicted to change the protein conformation with likely deleterious effect on its function as one of the fibroblast growth factor signaling mediators. In vitro cellular proliferation assay and in situ hypridization in vivo were then performed to understand the pathophysiology of the disease. The patients' skin fibroblasts showed an increased proliferation capacity compared to the controls' explaining the observed overgrowth phenotype. In addition, we detected Fibp expression most notably in the brains of mice embryos suggesting a possible effect on cognitive functions early in development. To date, only one patient has been reported with a homozygous nonsense mutation in FIBP exhibiting an overgrowth syndrome with multiple congenital abnormalities. Taken all together, these findings provide convincing evidence implicating FIBP aberrations in the newly recognized overgrowth syndrome and expand the associated phenotypes to include possible Wilms tumor predisposition. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteínas de Transporte/genética , Genes Recessivos , Transtornos do Crescimento/genética , Deficiência Intelectual/genética , Rim/anormalidades , Proteínas de Membrana/genética , Mutação , Tumor de Wilms/etiologia , Adolescente , Animais , Proliferação de Células , Criança , Pré-Escolar , Mapeamento Cromossômico , Análise Mutacional de DNA , Exoma , Feminino , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Estudos de Associação Genética , Genótipo , Transtornos do Crescimento/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Deficiência Intelectual/diagnóstico , Masculino , Camundongos , Camundongos Transgênicos , Linhagem , Fenótipo , Síndrome , Tumor de Wilms/diagnóstico
7.
Am J Med Genet A ; 170A(1): 156-61, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26395437

RESUMO

The gene encoding the AT-rich interaction domain-containing protein 1B (ARID1B) has recently been shown to be one of the most frequently mutated genes in patients with intellectual disability (ID). The phenotypic spectrums associated with variants in this gene vary widely ranging for mild to severe non-specific ID to Coffin-Siris syndrome. In this study, we evaluated three children from a consanguineous Emirati family affected with ID and dysmorphic features. Genomic DNA from all affected siblings was analyzed using CGH array and whole-exome sequencing (WES). Based on a recessive mode of inheritance, homozygous or compound heterozygous variants shared among all three affected children could not be identified. However, further analysis revealed a heterozygous variant (c.4318C>T; p.Q1440*) in the three affected children in an autosomal dominant ID causing gene, ARID1B. This variant was absent in peripheral blood samples obtained from both parents and unaffected siblings. Therefore, we propose that the most likely explanation for this situation is that one of the parents is a gonadal mosaic for the variant. To the best of our knowledge, this is the first report of a gonadal mosaicism inheritance of an ARID1B variant leading to familial ID recurrence.


Assuntos
Anormalidades Múltiplas/genética , Proteínas de Ligação a DNA/genética , Exoma/genética , Face/anormalidades , Deformidades Congênitas da Mão/genética , Deficiência Intelectual/genética , Micrognatismo/genética , Mosaicismo , Mutação/genética , Pescoço/anormalidades , Fatores de Transcrição/genética , Anormalidades Múltiplas/patologia , Adolescente , Criança , Face/patologia , Feminino , Deformidades Congênitas da Mão/patologia , Heterozigoto , Humanos , Deficiência Intelectual/patologia , Masculino , Micrognatismo/patologia , Pescoço/patologia , Linhagem , Irmãos
8.
Am J Hum Genet ; 91(6): 1073-81, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23176823

RESUMO

We report on four families affected by a clinical presentation of complex hereditary spastic paraplegia (HSP) due to recessive mutations in DDHD2, encoding one of the three mammalian intracellular phospholipases A(1) (iPLA(1)). The core phenotype of this HSP syndrome consists of very early-onset (<2 years) spastic paraplegia, intellectual disability, and a specific pattern of brain abnormalities on cerebral imaging. An essential role for DDHD2 in the human CNS, and perhaps more specifically in synaptic functioning, is supported by a reduced number of active zones at synaptic terminals in Ddhd-knockdown Drosophila models. All identified mutations affect the protein's DDHD domain, which is vital for its phospholipase activity. In line with the function of DDHD2 in lipid metabolism and its role in the CNS, an abnormal lipid peak indicating accumulation of lipids was detected with cerebral magnetic resonance spectroscopy, which provides an applicable diagnostic biomarker that can distinguish the DDHD2 phenotype from other complex HSP phenotypes. We show that mutations in DDHD2 cause a specific complex HSP subtype (SPG54), thereby linking a member of the PLA(1) family to human neurologic disease.


Assuntos
Genes Recessivos , Mutação , Fosfolipases/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Adulto , Sequência de Bases , Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Fácies , Feminino , Ordem dos Genes , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Linhagem , Fenótipo , Paraplegia Espástica Hereditária/diagnóstico , Adulto Jovem
9.
Eur J Pediatr ; 174(5): 661-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25388407

RESUMO

UNLABELLED: Transaldolase deficiency is a heterogeneous disorder of carbohydrate metabolism characterized clinically by dysmorphic features, cutis laxa, hepatosplenomegaly, hepatic fibrosis, pancytopenia, renal and cardiac abnormalities, and urinary excretion of polyols. This report describes four Emirati patients with transaldolase deficiency caused by the homozygous p.R192C missense mutation in TALDO1 displaying wide phenotypic variability. The patients had variable clinical presentations including hepatosplenomegaly, pancytopenia, liver failure, proteinuria, hydrops fetalis, cardiomyopathy, and skin manifestations (e.g., dryness, cutis laxa, ichthyosis, telangiectasias, and hemangiomas). Biochemical analyses including urinary concentration of polyols were consistent with transaldolase deficiency. The mutation p.R192C was previously identified in an Arab patient, suggesting a founder effect in Arab populations. CONCLUSION: The above findings support the premise that biallelic mutations in TALDO1 are responsible for transaldolase deficiency and confirm the broad phenotypic variability of this condition, even with the same genotype.


Assuntos
Erros Inatos do Metabolismo dos Carboidratos/genética , Mutação de Sentido Incorreto/genética , Transaldolase/deficiência , Transaldolase/genética , Adulto , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Recém-Nascido , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Emirados Árabes Unidos
10.
Metab Brain Dis ; 30(3): 687-94, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25227173

RESUMO

Deficiency of Asparagine Synthetase (ASNSD, MIM 615574) is a very rare autosomal recessive disorder presenting with some brain abnormalities. Affected individuals have congenital microcephaly and progressive encephalopathy associated with severe intellectual disability and intractable seizures. The loss of function of the asparagine synthetase (ASNS, EC 6.3.5.4), particularly in the brain, is the major cause of this particular congenital microcephaly. In this study, we clinically evaluated an affected child from a consanguineous Emirati family presenting with congenital microcephaly and epileptic encephalopathy. In addition, whole-exome sequencing revealed a novel homozygous substitution mutation (c.1193A > C) in the ASNS gene. This mutation resulted in the substitution of highly conserved tyrosine residue by cysteine (p.Y398C). Molecular modeling analysis predicts hypomorphic and damaging effects of this mutation on the protein structure and altering its enzymatic activity. Therefore, we conclude that the loss of ASNS function is most likely the cause of this condition in the studied family. This report brings the number of reported families with this very rare disorder to five and the number of pathogenic mutations in the ASNS gene to four. This finding extends the ASNS pathogenic mutations spectrum and highlights the utility of whole-exome sequencing in elucidation the causes of rare recessive disorders that are heterogeneous and/or overlap with other conditions.


Assuntos
Aspartato-Amônia Ligase/deficiência , Aspartato-Amônia Ligase/genética , Encefalopatias/genética , Epilepsia/genética , Microcefalia/genética , Transtornos Psicomotores/genética , Adolescente , Sequência de Aminoácidos , Encefalopatias/complicações , Encefalopatias/diagnóstico , Criança , Pré-Escolar , Epilepsia/complicações , Epilepsia/diagnóstico , Exoma/genética , Feminino , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/complicações , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Masculino , Microcefalia/complicações , Microcefalia/diagnóstico , Dados de Sequência Molecular , Linhagem , Estrutura Secundária de Proteína , Transtornos Psicomotores/complicações , Transtornos Psicomotores/diagnóstico
11.
Mol Biol Rep ; 41(1): 193-200, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24194196

RESUMO

Variants in the head and tail domains of the MYO7A gene, encoding myosin VIIA, cause Usher syndrome type 1B (USH1B) and nonsyndromic deafness (DFNB2, DFNA11). In order to identify the genetic defect(s) underling profound deafness in two consanguineous Arab families living in UAE, we have sequenced a panel of 19 genes involved in Usher syndrome and nonsyndromic deafness in the index cases of the two families. This analysis revealed a novel homozygous insertion of AG (c.1952_1953insAG/p.C652fsX11) in exon 17 of the MYO7A gene in an Iraqi family, and a homozygous point mutation (c.5660C>T/p.P1887L) in exon 41 affecting the same gene in a large Palestinian family. Moreover, some individuals from the Palestinian family also harbored a novel heterozygous truncating variant (c.1267C>T/p.R423X) in the DFNB31 gene, which is involved in autosomal recessive nonsyndromic deafness type DFNB31 and Usher syndrome type II. Assuming an autosomal recessive mode of inheritance in the two inbred families, we conclude that the homozygous variants in the MYO7A gene are the disease-causing mutations in these families. Furthermore, given the absence of retinal disease in all affected patients examined, particularly a 28 year old patient, suggests that at least one family may segregate a DFNB2 presentation rather than USH1B. This finding further supports the premise that the MYO7A gene is responsible for two distinct diseases and gives evidence that the p.P1887L mutation in a homozygous state may be responsible for nonsyndromic hearing loss.


Assuntos
Miosinas/genética , Adulto , Sequência de Bases , Criança , Pré-Escolar , Consanguinidade , Análise Mutacional de DNA , Surdez/genética , Feminino , Estudos de Associação Genética , Heterozigoto , Humanos , Lactente , Desequilíbrio de Ligação , Escore Lod , Masculino , Mutagênese Insercional , Miosina VIIa , Linhagem , Fenótipo , Emirados Árabes Unidos
12.
Childs Nerv Syst ; 30(7): 1183-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24413922

RESUMO

INTRODUCTION: Germline heterozygous mutations in the tumor suppresser NF1 gene cause a cancer predisposition syndrome known as neurofibromatosis type 1 (NF1). This disease is one of the most common multisystem disorders with an estimated incidence of 1 in 3,000 to 1 in 4,000 births. Clinically, NF1 patients are prone to develop "café au lait" spots, neurofibromas, Lisch nodules, freckling of the axillary, or inguinal region and optic nerve gliomas. MATERIALS AND METHODS: In the present study, we report clinical and molecular findings of five unrelated patients and seven cases from four families with NF1 from UAE. To reveal the genetic defects underlying NF1 in our cohort of patients, we screened the whole coding and splice site regions of the NF1 gene. In addition, MLPA or CGH array has been used to screen for structural variations including deletions, indels, and complex rearrangements. RESULTS: This resulted in the identification of five distinct novel mutations and two previously reported ones. These variations included three missense and one nonsense mutations, one single base, one dinucleotide, and one large deletion. CONCLUSION: Four mutations were inherited, and the remaining were absent from both parents and therefore are "de novo" mutations. This analysis represents the spectrum of NF1 mutations in UAE and supports the premise of absence of hotspot mutations in the NF1 gene. Moreover, no obvious genotype-phenotype correlations were observed in our patients.


Assuntos
Genes da Neurofibromatose 1 , Mutação , Neurofibromatose 1/genética , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex , Linhagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Emirados Árabes Unidos
13.
Mol Cancer Ther ; 23(1): 56-67, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37703580

RESUMO

Triple-negative breast cancer (TNBC) represents the most lethal and treatment-resistant breast cancer subtype with limited treatment options. We previously identified a protein complex unique to TNBC composed of the gap junction protein connexin 26 (Cx26), the pluripotency transcription factor NANOG, and focal adhesion kinase (FAK). We sought to determine whether a peptide mimetic of the interaction region of Cx26 attenuated tumor growth in preclinical models. We designed peptides based on Cx26 juxtamembrane domains and performed binding experiments with NANOG and FAK using surface plasmon resonance. Binding studies revealed that the Cx26 C-terminal tail and intracellular loop bound to NANOG and FAK with submicromolar-to-micromolar affinity and that a 5-amino acid sequence in the C-terminal tail of Cx26 (RYCSG) was sufficient for binding. Peptides with high affinity were engineered with a cell-penetrating antennapedia sequence and assessed in functional assays including cell proliferation, tumorsphere formation, and in vivo tumor growth, and downstream signaling changes were measured. The cell-penetrating Cx26 peptide (aCx26-pep) disrupted self-renewal while reducing nuclear FAK and NANOG and inhibiting NANOG target gene expression in TNBC cells but not luminal mammary epithelial cells. In vivo, aCx26-pep reduced tumor growth and proliferation and induced cell death. Here, we provide proof-of-concept that a Cx26 peptide-based strategy inhibits growth and alters NANOG activity specifically in TNBC, indicating the therapeutic potential of this targeting approach.


Assuntos
Peptídeos Penetradores de Células , Conexina 26 , Quinase 1 de Adesão Focal , Proteína Homeobox Nanog , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/terapia , Proteína Homeobox Nanog/antagonistas & inibidores , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Conexina 26/química , Conexina 26/uso terapêutico , Quinase 1 de Adesão Focal/antagonistas & inibidores , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/uso terapêutico
14.
Birth Defects Res A Clin Mol Teratol ; 97(12): 764-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24014090

RESUMO

BACKGROUND: Geleophysic dysplasia (GD) is an autosomal recessive disorder characterized by short stature, brachydactyly, stiff joints, thick skin, and cardiac valvular abnormalities that are often responsible for early death. Mutations in ADAMTSL2 and FBN1 genes have been shown to cause GD due to the dysregulation of transforming growth factor-ß signaling pathways. Small numbers of mutations in ADAMTSL2 have been reported so far in patients with GD type 1 (GD1). METHODS: In this study, we clinically evaluated two children from two consanguineous Arab families living in the United Arab Emirates with GD1. In addition we have sequenced all the coding exons of ADAMTSL2 gene using Sanger sequencing. RESULTS: The two patients exhibited most of the typical features of this rare bone dysplasia. Molecular analysis of the ADAMTSL2 gene revealed two novel homozygous missense mutations (c.938T>C, p.M313T and c.499G>A, p.D167N). The mutations segregated well in the studied families with the parents being heterozygous. In addition, bioinformatics analyses showed that these mutations are affecting conserved amino acids residues and thus strongly support their pathogenicity. CONCLUSION: We describe the clinical phenotypes of two patients with GD1 that are caused by two novel homozygous missense mutations in the ADAMTSL2 gene.


Assuntos
Proteínas ADAM/genética , Doenças do Desenvolvimento Ósseo/genética , Deformidades Congênitas dos Membros/genética , Metaloendopeptidases/genética , Mutação de Sentido Incorreto , Proteínas ADAMTS , Adulto , Sequência de Aminoácidos , Sequência de Bases , Doenças do Desenvolvimento Ósseo/patologia , Pré-Escolar , Consanguinidade , Éxons , Feminino , Genes Recessivos , Heterozigoto , Homozigoto , Humanos , Deformidades Congênitas dos Membros/patologia , Masculino , Dados de Sequência Molecular , Linhagem , Análise de Sequência de DNA , Emirados Árabes Unidos
15.
Cancer Res ; 83(24): 4142-4160, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37801613

RESUMO

Prostate cancer remains the second leading cause of cancer death in men in Western cultures. A deeper understanding of the mechanisms by which prostate cancer cells divide to support tumor growth could help devise strategies to overcome treatment resistance and improve survival. Here, we identified that the mitotic AGC family protein kinase citron kinase (CIT) is a pivotal regulator of prostate cancer growth that mediates prostate cancer cell interphase progression. Increased CIT expression correlated with prostate cancer growth induction and aggressive prostate cancer progression, and CIT was overexpressed in prostate cancer compared with benign prostate tissue. CIT overexpression was controlled by an E2F2-Skp2-p27 signaling axis and conferred resistance to androgen-targeted treatment strategies. The effects of CIT relied entirely on its kinase activity. Conversely, CIT silencing inhibited the growth of cell lines and xenografts representing different stages of prostate cancer progression and treatment resistance but did not affect benign epithelial prostate cells or nonprostatic normal cells, indicating a potential therapeutic window for CIT inhibition. CIT kinase activity was identified as druggable and was potently inhibited by the multikinase inhibitor OTS-167, which decreased the proliferation of treatment-resistant prostate cancer cells and patient-derived organoids. Isolation of the in vivo CIT substrates identified proteins involved in diverse cellular functions ranging from proliferation to alternative splicing events that are enriched in treatment-resistant prostate cancer. These findings provide insights into the regulation of aggressive prostate cancer cell behavior by CIT and identify CIT as a functionally diverse and druggable driver of prostate cancer progression. SIGNIFICANCE: The poorly characterized protein kinase citron kinase is a therapeutic target in prostate cancer that drives tumor growth by regulating diverse substrates, which control several hallmarks of aggressive prostate cancer progression. See related commentary by Mishra et al., p. 4008.


Assuntos
Próstata , Neoplasias da Próstata , Proteínas Quinases , Humanos , Masculino , Linhagem Celular Tumoral , Proliferação de Células , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais
16.
Endocr Relat Cancer ; 28(6): R141-R155, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33830069

RESUMO

Prostate cancer (CaP) remains the second leading cause of cancer deaths in Western men. These deaths occur because metastatic CaP acquires resistance to available treatments. The novel and functionally diverse treatment options that have been introduced in the clinic over the past decade each eventually induce resistance for which the molecular basis is diverse. Both initiation and progression of CaP have been associated with enhanced cell proliferation and cell cycle dysregulation. A better understanding of the specific pro-proliferative molecular shifts that control cell division and proliferation during CaP progression may ultimately overcome treatment resistance. Here, we examine literature for support of this possibility. We start by reviewing recently renewed insights in prostate cell types and their proliferative and oncogenic potential. We then provide an overview of the basic knowledge on the molecular machinery in charge of cell cycle progression and its regulation by well-recognized drivers of CaP progression such as androgen receptor and retinoblastoma protein. In this respect, we pay particular attention to interactions and reciprocal interplay between cell cycle regulators and androgen receptor. Somatic alterations that impact the cell cycle-associated and -regulated genes encoding p53, PTEN and MYC during progression from treatment-naïve, to castration-recurrent, and in some cases, neuroendocrine CaP are discussed. We considered also non-genomic events that impact cell cycle determinants, including transcriptional, epigenetic and micro-environmental switches that occur during CaP progression. Finally, we evaluate the therapeutic potential of cell cycle regulators and address challenges and limitations in the approaches modulating their action for CaP treatment.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Ciclo Celular , Divisão Celular , Progressão da Doença , Humanos , Masculino , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo
17.
Endocr Relat Cancer ; 28(6): L5-L10, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33852421

RESUMO

The recent genomic characterization of patient specimens has started to reveal the landscape of somatic alterations in clinical prostate cancer (CaP) and its association with disease progression and treatment resistance. The extent to which such alterations impact hallmarks of cancer is still unclear. Here, we interrogate genomic data from thousands of clinical CaP specimens that reflect progression from treatment-naïve, to castration-recurrent, and in some cases, neuroendocrine CaP for alterations in cell cycle-associated and -regulated genes, which are central to cancer initiation and progression. We evaluate gene signatures previously curated to evaluate G1-S and G2-M phase transitions or to represent the cell cycle-dependent proteome. The resulting CaP (stage)-specific overview confirmed the presence of well-known driver alterations impacting, for instance, the genes encoding p53 and MYC, and uncovered novel previously unrecognized mutations that affect others such as the PKMYT1 and MTBP genes. The cancer dependency and drugability of representative genomically altered cell cycle determinants were verified also. Taken together, these analyses on hundreds of often less-characterized cell cycle regulators expand considerably the scope of genomic alterations associated with CaP cell proliferation and cell cycle and isolate such regulatory proteins as putative drivers of CaP treatment resistance and entirely novel therapeutic targets for CaP therapy.


Assuntos
Neoplasias da Próstata , Ciclo Celular/genética , Humanos , Masculino , Proteínas de Membrana , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases
18.
Endocr Relat Cancer ; 27(6): R193-R210, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32276264

RESUMO

Prostate cancer (CaP) is the second leading cause of cancer-related deaths in Western men. Because androgens drive CaP by activating the androgen receptor (AR), blocking AR's ligand activation, known as androgen deprivation therapy (ADT), is the default treatment for metastatic CaP. Despite an initial remission, CaP eventually develops resistance to ADT and progresses to castration-recurrent CaP (CRPC). CRPC continues to rely on aberrantly activated AR that is no longer inhibited effectively by available therapeutics. Interference with signaling pathways downstream of activated AR that mediate aggressive CRPC behavior may lead to alternative CaP treatments. Developing such therapeutic strategies requires a thorough mechanistic understanding of the most clinically relevant and druggable AR-dependent signaling events. Recent proteomics analyses of CRPC clinical specimens indicate a shift in the phosphoproteome during CaP progression. Kinases and phosphatases represent druggable entities, for which clinically tested inhibitors are available, some of which are incorporated already in treatment plans for other human malignancies. Here, we reviewed the AR-associated transcriptome and translational regulon, and AR interactome involved in CaP phosphorylation events. Novel and for the most part mutually exclusive AR-dependent transcriptional and post-transcriptional control over kinase and phosphatase expression was found, with yet other phospho-regulators interacting with AR. The multiple mechanisms by which AR can shape and fine-tune the CaP phosphoproteome were reflected in diverse aspects of CaP biology such as cell cycle progression and cell migration. Furthermore, we examined the potential, limitations and challenges of interfering with AR-mediated phosphorylation events as alternative strategy to block AR function during CaP progression.


Assuntos
Fosforilação/genética , Proteoma/metabolismo , Receptores Androgênicos/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino
19.
Eur Urol Open Sci ; 22: 34-44, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33299986

RESUMO

BACKGROUND: Metastatic prostate cancer (CaP) treatments are evolving rapidly but without evidence-based biomarkers to predict responses, and to maximize remissions and survival. OBJECTIVE: To determine the activity of androgen receptor (AR), the target for default first-line systemic treatment, in localized treatment-naïve CaP and its association with clinical risk factors, molecular markers, CaP subtypes, and predictors of treatment response. DESIGN SETTING AND PARTICIPANTS: We examined 452 bona fide AR target genes in clinical-grade expression profiles from 6532 such CaPs collected between 2013 and 2017 by US physicians ordering the Decipher RP test. Results were validated in three independent smaller cohorts (n = 73, 90, and 127) and clinical CaP AR ChIP-Seq data. Association with CaP differentiation and progression was analyzed in independent datasets. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Unsupervised clustering of CaPs based on AR target gene expression was aligned with clinical variables, differentiation scores, molecular subtypes, and predictors of response to hormonal therapy, radiotherapy, and chemotherapy. AR target gene sets were analyzed via Gene Set Enrichment Analysis for differentiation and treatment resistance, Ingenuity Pathway Analysis for associated biology, and Cistrome for genomic AR binding site (ARBS) composition. RESULTS AND LIMITATIONS: Expression of eight AR target gene subsignatures gave rise to five CaP clusters, which were preferentially associated with CaP molecular subtypes, differentiation, and predictors of treatment response rather than with clinical variables. Subsignatures differed in contribution to CaP progression, luminal/basal differentiation, CaP biology, and ARBS composition. Validation in prospective trials and optimized quantitation are needed for clinical implementation. CONCLUSIONS: Measurement of AR activity patterns in treatment-naïve CaP may serve as a first branch of an evidence-based decision tree to optimize personalized treatment plans. PATIENT SUMMARY: Treatment options for metastatic prostate cancer are increasing without information needed to choose the right treatment for the right patient. We found variation in the behavior of the target for the default first-line therapy before treatment, which may help optimize treatment plans.

20.
Hum Genet ; 126(4): 575-87, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19526372

RESUMO

Posterior microphthalmia (PM) is a relatively rare autosomal recessive condition with normal anterior segment and small posterior segment resulting in high hyperopia and retinal folding. It is an uncommon subtype of microphthalmia that has been mostly reported to coexist with several other ophthalmic conditions and to occur in sporadic cases. The membrane-type frizzled-related protein (MFRP) is the only gene so far reported implicated in autosomal recessive, non-syndromic and syndromic forms of PM. Here, we performed a clinical and genetic analysis using six consanguineous families ascertained from different regions of Tunisia and affected with non-syndromic PM that segregates as an autosomal recessive trait. To identify the disease-causing defect in these families, we first analysed MFRP gene, then some candidate genes (CHX10, OPA1, MITF, SOX2, CRYBB1-3 and CRYBA4) and loci (MCOP1, NNO1 and NNO2) previously implicated in different forms of microphthalmia. After exclusion of these genes and loci, we performed a genome-wide scan using a high density single nucleotide polymorphism (SNP) array 50 K in a large consanguineous pedigree. SNP genotyping revealed eight homozygous candidate regions on chromosomes 1, 2, 3, 6, 15, 17 and 21. Linkage analysis with additional microsatellite markers only retained the 2q37.1 region with a maximum LOD score of 8.85 obtained for D2S2344 at theta = 0.00. Further investigations are compatible for linkage of four more families to this region with a refined critical interval of 2.35 Mb. The screening of five candidate genes SAG, PDE6D, CHRND, CHRNG and IRK13 did not reveal any disease-causing mutation.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 2/genética , Genes Recessivos , Ligação Genética , Microftalmia/genética , Adolescente , Adulto , Criança , Pré-Escolar , Consanguinidade , Família , Feminino , Genoma Humano , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos/genética , Homozigoto , Humanos , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Tunísia , Adulto Jovem
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