Genetic analysis of a Chinese pedigree affected with branchiootic syndrome due to a nonsense variant of EYA1 gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical phenotype and genetic basis for a Chinese pedigree suspected for branchiootic syndrome (BOS).@*METHODS@#The proband was subjected to target-capture high-throughput sequencing to detect potential variant of deafness-associated genes. Candidate variants were verified by Sanger sequencing of the family members.@*RESULTS@#The proband was found to harbor a c.1627C>T (p.Gln543Ter) nonsense variant of the EYA1 gene. Sanger sequencing confirmed that all of the 4 patients with the BOS phenotype from the pedigree have harbored the same heterozygous variant. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic (PVS1+PS+PP3+PP4).@*CONCLUSION@#The c.1627C>T (p.Gln543Ter) variant of the EYA1 gene probably underlay the BOS phenotype in this pedigree. Above finding has provided a basis for its clinical diagnosis.

Identification and genetic analysis of new mutations in EYA1 gene of BOS syndrome / 中华耳鼻咽喉头颈外科杂志

Objective: To analyze the clinical manifestations of a patient with branchiootic syndrome(BOS) and her families and to carry out genetic testing in order to specify the biological pathogenesis. Methods: Clinical data of the patient and her families were collected. Genomic DNA in the peripheral blood of the proband and her family members was extracted. All exons of 406 deafness-related susceptible genes as well as their flanking regions were sequenced by high-throughput sequencing, and the mutation sites of the proband and her parents were validated by Sanger sequencing. Results: There were nine members in three generations, of whom four presented with hearing loss, preauricular fistula and branchial fistula which met the diagnostic criteria of BOS. Proband and her mother presented with auricle malformation and inner ear malformation. And no one had abnormalities in the kidneys of all the patients. Pedigree analysis revealed that the mode of inheritance in the family was consistent with the autosomal dominant pattern. Mutational analysis showed that all the affected patients detected a heterozygous frameshift variation c.1255delT in the EYA1 gene, which had not been reported. Genotype and phenotype were co-isolated in this family. Such a frameshift variation produced a premature termination codon, thereby causing premature termination of translation (p.C419VFS*12). ACMG identified that the mutation was pathogenic. This mutation was novel and not detected in controls. A heterozygous missense variation mutation c.403G>A(p.G135S) in EYA1 gene was also detected in three members of this family. ACMG identified that the mutation clinical significance was uncertain. However, two of whom were normal, which seemed the disease was not caused by this mutation in this family. Conclusions: A novel frameshift mutation in EYA1(c.1255delT) is the main molecular etiology of BOS in the Chinese family. This study expands the mutational spectrum of EYA1 gene. The clinical manifestations are heterogeneous among patients in this family. The diagnosis of BOS should combine gene tests with clinical phenotypes analysis.

Two naturally derived small molecules disrupt the sineoculis homeobox homolog 1-eyes absent homolog 1 (SIX1-EYA1) interaction to inhibit colorectal cancer cell growth / 中华医学杂志(英文版)

BACKGROUND@#Emerging evidence indicates that the sineoculis homeobox homolog 1-eyes absent homolog 1 (SIX1-EYA1) transcriptional complex significantly contributes to the pathogenesis of multiple cancers by mediating the expression of genes involved in different biological processes, such as cell-cycle progression and metastasis. However, the roles of the SIX1-EYA1 transcriptional complex and its targets in colorectal cancer (CRC) are still being investigated. This study aimed to investigate the roles of SIX1-EYA1 in the pathogenesis of CRC, to screen inhibitors disrupting the SIX1-EYA1 interaction and to evaluate the efficiency of small molecules in the inhibition of CRC cell growth.@*METHODS@#Real-time quantitative polymerase chain reaction and western blotting were performed to examine gene and protein levels in CRC cells and clinical tissues (collected from CRC patients who underwent surgery in the Department of Integrated Traditional and Western Medicine, West China Hospital of Sichuan University, between 2016 and 2018, n = 24). In vivo immunoprecipitation and in vitro pulldown assays were carried out to determine SIX1-EYA1 interaction. Cell proliferation, cell survival, and cell invasion were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, clonogenic assay, and Boyden chamber assay, respectively. The Amplified Luminescent Proximity Homogeneous Assay Screen (AlphaScreen) method was used to obtain small molecules that specifically disrupted SIX1-EYA1 interaction. CRC cells harboring different levels of SIX1/EYA1 were injected into nude mice to establish tumor xenografts, and small molecules were also injected into mice to evaluate their efficiency to inhibit tumor growth.@*RESULTS@#Both SIX1 and EYA1 were overexpressed in CRC cancerous tissues (for SIX1, 7.47 ± 3.54 vs.1.88 ± 0.35, t = 4.92, P = 0.008; for EYA1, 7.61 ± 2.03 vs. 2.22 ± 0.45, t = 6.73, P = 0.005). The SIX1/EYA1 complex could mediate the expression of two important genes including cyclin A1 (CCNA1) and transforming growth factor beta 1 (TGFB1) by binding to the myocyte enhancer factor 3 consensus. Knockdown of both SIX1 and EYA1 could decrease cell proliferation, cell invasion, tumor growth, and in vivo tumor growth (all P < 0.01). Two small molecules, NSC0191 and NSC0933, were obtained using AlphaScreen and they could significantly inhibit the SIX1-EYA1 interaction with a half-maximal inhibitory concentration (IC50) of 12.60 ± 1.15 μmol/L and 83.43 ± 7.24 μmol/L, respectively. Administration of these two compounds could significantly repress the expression of CCNA1 and TGFB1 and inhibit the growth of CRC cells in vitro and in vivo.@*CONCLUSIONS@#Overexpression of the SIX1/EYA1 complex transactivated the expression of CCNA1 and TGFB1, causing the pathogenesis of CRC. Pharmacological inhibition of the SIX1-EYA1 interaction with NSC0191 and NSC0933 significantly inhibited CRC cell growth by affecting cell-cycle progression and metastasis.

Distribution of Serotypes and Antibiotic Susceptibility Patterns Among Invasive Pneumococcal Diseases in Saudi Arabia

BACKGROUND: Streptococcus pneumoniae causes life-threatening infections such as meningitis, pneumonia, and febrile bacteremia, particularly in young children. The increasing number of drug-resistant isolates has highlighted the necessity for intervening and controlling disease. To achieve this, information is needed on serotype distribution and patterns of antibiotic resistance in children. METHODS: All cases of invasive pneumococcal disease (IPD) in children aged less than 15 yr recorded at King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia, were reviewed for serotyping and antibiotic susceptibility. Isolates were collected from 78 consecutive patients with IPD between 2009 and 2012. All collected isolates were subjected to serotyping by co-agglutination, sequential multiplex PCR, and single PCR sequetyping as previously described. RESULTS: The most frequently isolated IPD serotypes were 23F, 6B, 19F, 18C, 4, 14, and 19A, which are listed in decreasing order and cover 77% of total isolates. The serotype coverage for the pneumococcal conjugate vaccine (PCV)7, PCV10, and PCV13 was 77%, 81%, and 90%, respectively. Results from sequential multiplex PCR agreed with co-agglutination results. All serotypes could not be correctly identified using single PCR sequetyping. Minimum inhibitory concentration showed that 50 (64%) isolates were susceptible to penicillin, whereas 70 (90%) isolates were susceptible to cefotaxime. CONCLUSIONS: The most common pneumococcal serotypes occur with frequencies similar to those found in countries where the PCV has been introduced. The most common serotypes in this study are included in the PCVs. Addition of 23A and 15 to the vaccine would improve the PCV performance in IPD prevention.

Trypanosoma rangeli protein tyrosine phosphatase is associated with the parasite's flagellum

Protein tyrosine phosphatases (PTPs) play an essential role in the regulation of cell differentiation in pathogenic trypanosomatids. In this study, we describe a PTP expressed by the non-pathogenic protozoan Trypanosoma rangeli (TrPTP2). The gene for this PTP is orthologous to the T. brucei TbPTP1 and Trypanosoma cruzi (TcPTP2) genes. Cloning and expression of the TrPTP2 and TcPTP2 proteins allowed anti-PTP2 monoclonal antibodies to be generated in BALB/c mice. When expressed by T. rangeli epimastigotes and trypomastigotes, native TrPTP2 is detected as a ~65 kDa protein associated with the parasite's flagellum. Given that the flagellum is an important structure for cell differentiation in trypanosomatids, the presence of a protein responsible for tyrosine dephosphorylation in the T. rangeli flagellum could represent an interesting mechanism of regulation in this structure.

Floppy infant caused by MTM1 mutation: a first genetically-confirmed X-linked myotubular myopathy patient in Thailand.

Floppy infant syndrome (FIS) refers to a condition wherein an infant manifests generalized hypotonia since birth or in early life. It is heterogeneous and can be caused by various central nervous system disorders, neuromuscular diseases and genetic disorders. X-linked myotubular myopathy (XMTM) is a progressive congenital myopathy morphologically characterized by the presence of centrally placed nuclei in numerous muscle fibers without any other particular pathological abnormalities. Patients are frequently born with floppiness and respiratory distress. The vast majority of patients carry a truncating or missense mutation in MTM1. The authors report here a full term male baby with clinicopathological features of XMTM. The diagnosis is validated by the finding of a c. 141-144delAGAA mutation ofMTM1. To the best of the authors' knowledge, the present case is the first genetically confirmed XMTM in Thailand. A brief review of various neuromuscular disorders causing floppy infant syndrome is also included.

Interaction between chicken protein tyrosine phosphatase 1 (CPTP1)-like rat protein phosphatase 1 (PTP1) and p60v-src in v-src-transformed Rat-1 fibroblasts

CPTP1 is a nontransmembrane chicken protein tyrosine phosphatase having 92% sequence homology to the corresponding 321 amino acids of human protein tyrosine phosphatase 1B (HPTP1B). Using anti-CPTP1 antibody, we identified CPTP1-like rat PTP1 of 51 kappa Da in Rat-1 and v-src-transformed Rat-1 fibroblasts. Here we show that CPTP1-like rat PTP1 binds to p60v-src in vivo and CPTP1 also can associate with p60v-src in cell lysate of v-src- transformed Rat-1 fibroblasts. Interaction between HPTP1B-type PTPs, CPTP1-like rat PTP1 and CPTP1, and p60v-src was reduced by vanadate treatment for 13 h due to down regulation of the protein level of p60v-src in vivo. Interestingly, CPTP1-like rat PTP1 was coimmunoprecipitated with a 70-kappa Da protein which has a possibility to be tyrosine- phosphorylated by p60v-src in v-src-transformed Rat- 1 fibroblasts. These results suggest that HPTP1B- type PTPs may play an important role in p60src dependent signal pathway in eucaryotic cells.

Expresión del gen PRL-1, en células de melanoma murino B-16, inducidas a supresión del crecimiento con el sensibilizador a la radiación ultravioleta: bromodeoxiuridina / Expression of the PRL-1 gene in B-16 murine melanoma cells induce to growth suppression in the ultraviolet radiation sensitizer bromodeoxiuridin

El cáncer es una enfermedad del genoma, en el cual múltiples aberraciones genéticas conducen a la activación de oncogenes y a la inactivación de genes supresores tumorales, promoviendo un desequilibrio en el control de la proliferación, diferenciación y muertecelular. Las células tumorales pueden ser inducidas a un crecimiento controlado y a diferenciación terminal in vitro por tratamiento farmacológico que conduce a la restauración parcial del fenotipo celular normal. Sin embargo, el uso de inductores farmacológicos de diferenciarón, supresión del crecimiento y muerte celular como el ácido retinoíco, vitamina D, L-tirosina y bromodeoxiuridina, es limitado debido a que no se conocen los mecanismos moleculares y sus blancos de acción. La Bromodeoxiuridina, es un análogo de la timina, sensibilizador a la radiación ultravioleta e inductor de la supresión del crecimiento. Sin embargo, las bases moleculares de estas acciones no se conocen muy bien. La identificación de genes blancos moleculares (como cinasas y fosfatasas) de la Bromodeoxiuridina (BrdU) y su papel en el control de la proliferación celular y la radiosensibilización, conduciría al entendimiento y desarrollo de potenciales agentes terapéuticos para el control de la proliferación en células tumorales, como tratamiento alternativo a la quimioterapia y radioterapia convencionales, las cuales son altamente agresivas no sólo para las células tumorales, sino también para las células normales en proliferación. Los genes que codifican para proteínas fosfatasas se han implicado en la tumorigénesis. Recientemente en el laboratorio de fisiología molecular del INS se clonó y se secuenció el cADN que codifica para la tirosina fosfatasa PRL-1. Sin embargo, no se sabe si sus niveles de expresión cambian en células de melanoma proliferantes e inducidas a supresión del crecimiento y diferenciación celular. Por lo tanto, el objetivo de este trabajo fue determinar el nivel de expresión de ARN del gen que codifica para la tirosina-fosfatasa PRL-1, en células de melanoma murino B-16 inducidas a supresión del crecimiento y diferenciación celular. Por lo tanto, el objetivo de este trabajo fue determinar el nivel de expresión del ARN del gen que codifica para la tirosina-fosfatasa PRL-1, en células de melanoma murino B-16 inducidas a supresión del crecimiento por el tratamiento con Bromodeoxiuridina, radiación ultravioleta tipo C y sensibilización...