Browsing by Subject "Mutation"
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- PublicationOpen AccessAmelioration of the severity of heparin-binding antithrombin mutations by posttranslational mosaicism(American Society of Hematology, 2012-04-12) Martínez-Martínez, Irene; Navarro-Fernández, José; Ostergaad, Alice; Gutierrez-Gallego, Ricardo; Padilla, José; Miñano, Antonia; Pascual, Cristina; Martínez, Constantino; Morena-Barrio, María Eugenia de la; Pedersen, Shona; Kristensen, Soren Risom; Corral, Javier; Bohdan, Nataliya; Morena Barrio, María Eugenia de la; Águila Martínez, Sonia; Vicente García, Vicente; Corral de la Calle, Javier; MedicinaThe balance between actions of procoagulant and anticoagulant factors protects organisms from bleeding and thrombosis. Thus, antithrombin deficiency increases the risk of thrombosis, and complete quantitative deficiency results in intrauterine lethality. However, patients homozygous for L99F or R47C antithrombin mutations are viable. These mutations do not modify the folding or secretion of the protein, but abolish the glycosaminoglycan-induced activation of antithrombin by affecting the heparin-binding domain. We speculated that the natural β-glycoform of antithrombin might compensate for the effect of heparin-binding mutations. We purified α- and β-antithrombin glycoforms from plasma of 2 homozygous L99F patients. Heparin affinity chromatography and intrinsic fluorescence kinetic analyses demonstrated that the reduced heparin affinity of the α-L99F glycoform (K(D), 107.9 ± 3nM) was restored in the β-L99F glycoform (K(D), 53.9 ± 5nM) to values close to the activity of α-wild type (K(D), 43.9 ± 0.4nM). Accordingly, the β-L99F glycoform was fully activated by heparin. Similar results were observed for recombinant R47C and P41L, other heparin-binding antithrombin mutants. In conclusion, we identified a new type of mosaicism associated with mutations causing heparin-binding defects in antithrombin. The presence of a fully functional β-glycoform together with the activity retained by these variants helps to explain the viability of homozygous and the milder thrombotic risk of heterozygous patients with these specific antithrombin
- PublicationOpen AccessCRISPR-mediated WNK4 point mutation aggravates tumor progression and weakens chemotherapy sensitivity in gastric cancer(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2025) Ying, Xiaojun; Ying, Zhen; Gao, Xiaobing; Wang, Yong; Lv, XintingObjective. Gastric cancer (GC) is the fifth most common malignancy, the molecular targets of which have been increasingly explored in recent years. As a serine/threonine protein kinase, the role of WNK lysine deficient protein kinase 4 (WNK4) in GC was clarified in this study. Methods. Human GC lines AGS and MKN45 were stably transfected with a WNK4 mutant constructed by the CRISPR/Cas9 method and treated with cis-dichlorodiammine platinum (CDDP, 2 μg/mL) and 5-fluorouracil (5-FU, 5 μg/mL) for 48h. Tumor-bearing mice were established with 5×106 mutant-type AGS cells, and injected with 40 mg/kg WP1066, the inhibitor of signal transducer and activator of transcription 3 (STAT3), for 21 days. Cell malignant potential and tumor growth were assessed. STAT3 activation was identified by western blot and immunohistochemistry. The interaction between WNK4 and STAT3 was determined using co-immunoprecipitation and immunofluorescence co-localization. Results. WNK4 mutation promoted proliferation and invasion, and upregulated the p-STAT3/STAT3 value in GC cells with/without 5-FU and CDDP treatments, while inhibiting apoptosis of GC cells without drug treatment. In tumor-bearing mice, WNK4 mutation accelerated tumor growth, increased levels of p-STAT3, STAT3, and p-STAT3/STAT3, and strengthened the co-immunoprecipitation and co-localizing with STAT3; however, these effects were reversed by WP1066 treatment. Conclusion. Through activating STAT3, WNK4 mutation impacts both the natural and drug-treated growth of GC cells or tumors, suggesting a new avenue for preclinical research.
- PublicationOpen AccessH3F3A G34 mutation DNA sequencing and G34W immunohistochemistry analysis in 366 cases of giant cell tumors of bone and other bone tumors(Universidad de Murcia. Departamento de Biología Celular e Histología, 2021) Gong, Lihua; Bui, Marilyn M.; Zhang, Wen; Sun, Xiaoqi; Zhang, Ming; Yi, DingH3F3A mutations and the expression of glycine 34 to tryptophan (G34W) mutants in giant cell tumors of bone (GCTBs) and other bone tumors were detected to compare H3F3A mutation types and the expression of G34W-mutant protein in order to provide a theoretical basis for using H3F3A mutations as a diagnostic and differential-diagnostic tool for GCTBs. A total of 366 bone tumor cases were investigated. The cases involved 215 men and 151 women, whose median age was 29 years (3-84). The cases included GCTB (n=180), recurrent GCTB (n=19), GCTB with lung metastasis (n=5), pediatric GCTB (n=15), primary malignant GCTB (n=5), chondroblastoma (CB, n=61), chondrosarcoma grade II (n=15), dedifferentiated chondrosarcoma (n=17), chondromyxoid fibroma (n=9), aneurysmal bone cyst (n=9), nonossifying fibroma (n=9), osteosarcoma (n=16), and undifferentiated sarcoma (n=6). Sanger DNA sequencing analysis was used to detect H3F3A mutations. Immunohistochemistry was used to assess the expression of the G34W-mutated protein in these bone tumors. DNA sequencing results revealed H3F3A mutations in 95.00% of GCTBs (171/180), including glycine 34 to tryptophan (G34W, 163/180, 90.56%), glycine 34 to leucine (G34L, 3/180, 1.67%), glycine 34 to valine (G34V, 3/180, 1.67%), and glycine 34 to arginine (G34R, 2/180, 1.11%). Recurrent GCTBs mostly had the H3F3A G34W mutation (18/19, 94.74%), and GCTBs with lung metastasis all had the H3F3A G34W mutation (5/5, 100%). Pediatric GCTBs had a mutation rate of 93.33% (14/15), including one case with G34L. Four cases of primary malignant GCTB showed the H3F3A G34W mutation (4/5, 80.00%), and the classical GCTB component and malignant component showed consistent mutation types. Immunohistochemistry showed that GCTBs harboring G34W also expressed the mutant protein in tumor cell nuclei. Furthermore, one case of GCTB and one case of recurrent GCTB showed positive G34W immunostaining results despite being negative for the genetic mutation. Other bone tumors all showed wildtype expression in both DNA sequencing and immunohistochemistry. Our large-sample DNA sequencing analysis detected four different forms of mutations in GCTBs, including three rare mutation forms. The most common mutation of H3F3A was G34W, which was in accordance with the expression of G34W in GCTBs detected by immunohistochemistry. Although DNA sequencing analysis detected rare mutation types of H3F3A, false-negative results were also present due to the small number of cells in the samples. Detection of the most common (G34W) mutant protein by immunohistochemistry was more convenient. Given the high prevalence of these driver mutations, the detection of H3F3A mutant proteins can assist in the diagnosis of GCTB and its differential diagnosis from other bone tumors.
- PublicationOpen AccessItinéraire erratique et mutation identitaire dans "Desirada" de M. Condé.(Universidad de Murcia, Servicio de Publicaciones., 2020) Eyenga Onana, Pierre SuzanneResumen: ¿De qué manera el fenómeno de la inmigración hace que los migrantes cambien su identidad psicológica, socioprofesional y cultural has-ta el punto de convertirse en seres híbridos? Basado en la sociocrítica de Henri Mitterand, este estudio está organizado en tres partes. En primer lugar, mostramos cómo la inmigración resulta ser un escollo en el proceso de construcción de la identidad del migrante, así como un trampolín para reinventarse en el espacio extranjero. A continuación, observamos la dimensión estética que nos permite captar la no-vela principalmente como una obra de arte y no como un libro de texto de historia. Por último, ilustramos que la identidad, en la Desirada de Condé, resulta de la suma de las culturas que el migrante encuentra a lo largo de su errático itinerario
- PublicationOpen AccessThrombocytopenia in leukemia: Pathogenesis and prognosis(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Shahrabi, Saeid; Maleki Behzad, Masumeh; Jaseb, Kaveh; Saki, NajmaldinLeukemias, a heterogeneous group of hematological disorders, are characterized by ineffective hematopoiesis and morphologic abnormalities of hematopoietic cells. Thrombocytopenia is a common problem among leukemia types that can lead to hemorrhagic complications in patients. The purpose of this review article is to identify the conditions associated with the incidence of thrombocytopenia in leukemias. It can be stated that although translocations have been considered responsible for this complication in many studies, other factors such as bone marrow failure, genes polymorphism, a mutation in some transcription factors, and the adverse effects of treatment could be associated with pathogenesis and poor prognosis of thrombocytopenia in leukemias. Considering the importance of thrombocytopenia in leukemias, it is hoped that the recognition of risk factors increasing the incidence of this complication in leukemic patients would be useful for prevention and treatment of this disorder.
- PublicationRestrictedUnclassifiable arrhythmic cardiomyopathy associated with Emery–Dreifuss caused by a mutation in FHL1(Wiley, 2016-02-09) San Román, I.; Martínez, F.; Albert, L.; Polo, L.; Guardiola, J.; García-Molina, E.; Muñoz-Esparza, C.; López-Ayala, J.M.; Sabater Molina, María; Gimeno Blanes, Juan Ramón; Medicina; Facultad de MedicinaEmery–Dreifuss muscular dystrophy (EDMD) is a heterogeneous genetic disorder characterized by peripheral muscular weakness often associated with dilated cardiomyopathy. We characterize clinically a large family with a mutation in FHL1 gene (p.Cys255Ser). Penetrance was 44%, 100% for males and 18% for females. The heart was the main organ involved. Affected adult males had mild hypertrophy, systolic dysfunction and restriction with non-dilated ventricles. Carriers had significant QTc prolongation. The proband presented with resuscitated cardiac arrest. There were two transplants. Pathological study of explanted heart showed fibrofatty replacement and scarring consistent with arrhythmogenic cardiomyopathy and prominent left ventricular trabeculations. Myopathic involvement was evident in all males. Females had no significant neuromuscular disease. Mutations in FHL1 cause unclassifiable cardiomyopathy with coexisting EDMD. Prognosis is poor and systolic impairment and arrhythmias are frequent. Thrombopenia and raised creatine phosphokinase should raise suspicion of an FHL-1 disorder in X-linked cardiomyopathy.