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1.
Mol Phylogenet Evol ; 191: 107987, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38081401

RESUMEN

Ancient lakes are a hotspot of biodiversity. Freshwater species often experience spectacular species radiation after colonizing lakes from riverine habitats. Therefore, the relationship between the fauna of the ancient lakes and the surrounding riverine system has a special significance in understanding their origin and evolutionary history. The study of ancient lake species often focused on the lake colonization of riverine species. In contrast, far less attention has been placed on the reverse direction: the riverine colonization of the lake species, despite its importance in disentangling their complex evolutionary history. The freshwater snails in the genus Semisulcospira involve endemic groups that radiated in the ancient Lake Biwa. Using genetics and fossil records, we inferred that the ancestors of these lake-endemic Semisulcospira snails historically colonized the riverine habitats at least three times during the Middle Pleistocene. Each colonization resulted in the formation of a new lineage that was genetically and morphologically distinct from other lineages. Further, one of these colonizations was followed by hybridization with a cosmopolitan riverine species, which potentially facilitated the population persistence of the colonizers in the new environment. Despite their complex histories, all these colonizers were currently grouped within a single species, Semisulcospira kurodai, suggesting cryptic diversity in this species. This study highlights the significance of the riverine colonizations of the lake species to fully understand the diversification history of freshwater fauna in and around the ancient lakes.


Asunto(s)
Evolución Biológica , Lagos , Animales , Filogenia , Caracoles/genética , Caracoles/anatomía & histología , Ecosistema
2.
J Evol Biol ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39037492

RESUMEN

Determining species boundaries within rapidly evolving species flocks is essential to understanding their evolutionary history but is often difficult to achieve due to the lack of clear diagnostic features. Ancient Lake Biwa harbors endemic snails in the genus Semisulcospira, a species flock with 19 described species. However, their morphological and genetic similarity cast doubt on the validity of their species status and their histories of explosive speciation. To evaluate their species boundaries, we examine patterns of gene flow among the sympatric or parapatric nominal Semisulcospira species in Lake Biwa. The principal component analysis and Bayesian structure analysis based on the genome-wide genotyping dataset demonstrated no gene flow between five pairs of the Semisulcospira species. However, we found the hybrids between the closely related species pair, Semisulcospira decipiens and S. rugosa. Despite the presence of hybrids, these nominal species still formed their own genetic clusters. There are variations in the chromosome numbers among these species, potentially providing an intrinsic barrier to panmictic gene flow. Our study showed complete or partial reproductive isolation among the sympatric or parapatric Semisulcospira species, demonstrating that the Semisulcospira snails are real species assemblages radiated in Lake Biwa. Our study provides significant implications for establishing species boundaries among rapidly evolving freshwater species in ancient lakes.

3.
Gastric Cancer ; 26(1): 116-122, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36040575

RESUMEN

BACKGROUND AND STUDY AIMS: The diagnostic ability of endoscopists to determine invasion depth of early gastric cancer is not favorable. We designed an artificial intelligence (AI) classifier for differentiating intramucosal and submucosal gastric cancers and examined it to establish a diagnostic method based on cooperation between AI and endoscopists. PATIENTS AND METHODS: We prepared 500 training images using cases of mainly depressed-type early gastric cancer from 250 intramucosal cancers and 250 submucosal cancers. We also prepared 200 test images each of 100 cancers from another institution. We designed an AI classifier to differentiate between intramucosal and submucosal cancers by deep learning. We examined the performance of the AI classifier and the majority vote of the endoscopists as high confidence and low confidence diagnostic probability, respectively, and cooperatively combined them to establish a diagnostic method providing high accuracy. RESULTS: Internal evaluation of the training images showed that accuracy, sensitivity, specificity, and F1 measure by the AI classifier were 77%, 76%, 78%, and 0.768, and those of the majority vote of the endoscopists were 72.6%, 53.6%, 91.6%, and 0.662, respectively. A diagnostic method based on cooperation between AI and the endoscopists showed that the respective values were 78.0%, 76.0%, 80.0%, and 0.776 for the test images. The value of F1 measure was especially higher than those by AI or the endoscopists alone. CONCLUSIONS: Cooperation between AI and endoscopists improved the diagnostic ability to determine invasion depth of early gastric cancer.


Asunto(s)
Inteligencia Artificial , Neoplasias Gástricas , Humanos , Detección Precoz del Cáncer , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía , Endoscopía , Aprendizaje Profundo
4.
Mol Phylogenet Evol ; 175: 107563, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35809852

RESUMEN

Accurate species identification is of primary importance in ecology and evolutionary biology. For a long time, the unionid mussels Beringiana and Sinanodonta have puzzled researchers trying to unravel their diversity because of their poorly discernible morphologies. A recent study conducted species delineation of unionid mussels based on mitochondrial DNA variation, opening up a new avenue to grasp species diversity of the mussels. However, mtDNA-based classification may not align with species boundaries because mtDNA is prone to introgression and incomplete lineage sorting that cause discordance between species affiliation and gene phylogeny. In this study, we evaluated the validity of the mtDNA-based classification of unionid mussels Beringiana and Sinanodonta in Japan using mitochondrial sequence data, double digest restriction site-associated DNA library (ddRAD) sequencing, and morphological data. We found significant inconsistencies in the mitochondrial and nuclear DNA phylogenies, casting doubt on the reliability of the mtDNA-based classification in this group. In addition, nuclear DNA phylogeny revealed that there are at least two unionid lineages hidden in the mtDNA phylogeny. Although molecular dating technique indicates that Beringiana and Sinanodonta diverged >35 million years ago, their shell morphologies are often indistinguishable. Specifically, morphological analyses exhibited the parallel appearance of nearly identical ball-like shell forms in the two genera in Lake Biwa, which further complicates species identification and the morphological evolution of unionid mussels. Our study adds to a growing body of literature that accurate species identification of unionid mussels is difficult when using morphological characters alone. Although mtDNA-based classification is a simple and convenient way to classify unionid mussels, considerable caution is warranted for its application in ecological and evolutionary studies.


Asunto(s)
Bivalvos , Unionidae , Animales , Bivalvos/genética , ADN Mitocondrial/genética , Japón , Filogenia , Reproducibilidad de los Resultados , Unionidae/genética
5.
Int J Mol Sci ; 22(7)2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33810223

RESUMEN

DNA can adopt various structures besides the B-form. Among them, cruciform structures are formed on inverted repeat (IR) sequences. While cruciform formable IRs (CFIRs) are sometimes found in regulatory regions of transcription, their function in transcription remains elusive, especially in eukaryotes. We found a cluster of CFIRs within the mouse Pou5f1 enhancer. Here, we demonstrate that this cluster or some member(s) plays an active role in the transcriptional regulation of not only Pou5f1, but also Sox2, Nanog, Klf4 and Esrrb. To clarify in vivo function of the cluster, we performed genome editing using mouse ES cells, in which each of the CFIRs was altered to the corresponding mirror repeat sequence. The alterations reduced the level of the Pou5f1 transcript in the genome-edited cell lines, and elevated those of Sox2, Nanog, Klf4 and Esrrb. Furthermore, transcription of non-coding RNAs (ncRNAs) within the enhancer was also upregulated in the genome-edited cell lines, in a similar manner to Sox2, Nanog, Klf4 and Esrrb. These ncRNAs are hypothesized to control the expression of these four pluripotency genes. The CFIRs present in the Pou5f1 enhancer seem to be important to maintain the integrity of ES cells.


Asunto(s)
Elementos de Facilitación Genéticos , Células Madre Embrionarias de Ratones/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Animales , Línea Celular , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Ratones , Proteína Homeótica Nanog/genética , Proteína Homeótica Nanog/metabolismo , Conformación de Ácido Nucleico , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Activación Transcripcional , Regulación hacia Arriba
6.
Lab Invest ; 100(3): 353-362, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31527828

RESUMEN

Cancer cells, including malignant lymphoma cells, alter their metabolism, termed "metabolic reprograming," on initiation of malignant transformation as well as upon accumulation of genetic abnormalities. Here, to identify a novel therapeutic target involved in the metabolic changes during malignant lymphoma, we performed global analyses combined with shotgun proteomics, in silico database analysis, and clinic-pathologic analysis of nonneoplastic lymphoid tissue and malignant lymphoma tissue and verified the molecular functions in vitro. In total, 2002 proteins were detected from both samples and proteins related to fatty acid beta-oxidation (FAO) were detected more frequently in malignant lymphoma tissue. Consequently, the most frequently detected protein, the mitochondrial trifunctional enzyme subunit-alpha (HADHA), was identified as a potential target. Immunohistochemical analyses revealed that HADHA tended to be overexpressed in a high-grade subtype of malignant lymphoma tissue. Clinicopathologic study revealed that HADHA overexpression was correlated with significantly worse overall survival (P = 0.013) and was an independent prognostic predictor in diffuse large B-cell lymphoma (P = 0.027). In vitro, downregulation of HADHA negatively regulated cell growth by causing G0/G1 arrest (P = 0.0008) similar to treatment with etomoxir, an inhibitor of FAO (P = 0.032). Moreover, downregulation of HADHA increased the susceptibility to doxorubicin (P = 0.002) and etoposide (P = 0.004). Moreover, these phenotypes were confirmed in an HADHA knockout system. Thus, we provide a basis for a novel therapeutic strategy through the regulation of HADHA and FAO in patients with refractory malignant lymphoma.


Asunto(s)
Linfoma , Subunidad alfa de la Proteína Trifuncional Mitocondrial , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Descubrimiento de Drogas , Ácidos Grasos/metabolismo , Femenino , Humanos , Tejido Linfoide/química , Tejido Linfoide/metabolismo , Linfoma/metabolismo , Linfoma/mortalidad , Linfoma/patología , Masculino , Persona de Mediana Edad , Subunidad alfa de la Proteína Trifuncional Mitocondrial/antagonistas & inhibidores , Subunidad alfa de la Proteína Trifuncional Mitocondrial/genética , Subunidad alfa de la Proteína Trifuncional Mitocondrial/metabolismo , Oxidación-Reducción , Proteoma/análisis , Proteoma/metabolismo
7.
Cancer Sci ; 111(4): 1417-1421, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32056332

RESUMEN

The characteristics of tumor cells of primary vitreoretinal lymphoma (PVRL) have not been defined, although researches have shown that most cases are of diffuse large B-cell lymphoma (DLBCL). To determine the subtype and biological characteristics of tumor cells of PVRL, we performed a gene expression profiling analysis. RNA was extracted from the vitreous fluid of 7 PVRL patients and from nodal samples of 10 DLBCL patients: 6 of germinal center B-cell (GCB) type and 4 of activated B-cell (ABC) type determined by Hans' criteria. Six PVRL samples showed gene expression profiles that were similar to each other. The patterns were different from those of the ABC-type nodular DLBCL but relatively close to those of the GCB-type nodular DLBCL. Interestingly, all of the 6 examined PVRL samples had either MYD88L265P or mutation in the immunoreceptor tyrosine-based activation motif (ITAM) region of CD79B. Five PVRL patients with similar gene expression profiles were treated with a standardized regimen: intravitreal administration of methotrexate (MTX) followed by six courses of systemic high doses of MTX. As a result, 2 patients had CD79B mutations and showed early central nervous system (CNS) progression. Patients without CNS progression did not have this mutation. In conclusion, PVRL had unique genetic features: an expression pattern different from ABC-type and relatively close to GCB-type DLBCL. CD79B mutations showed potential to serve as prognostic markers for CNS progression.


Asunto(s)
Antígenos CD79/genética , Linfoma de Células B Grandes Difuso/genética , Neoplasias de la Retina/genética , Cuerpo Vítreo/metabolismo , Anciano , Linfocitos B/patología , Biomarcadores de Tumor/genética , Sistema Nervioso Central/patología , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Linfoma de Células B Grandes Difuso/patología , Masculino , Análisis por Micromatrices , Mutación , Neoplasias de la Retina/patología , Cuerpo Vítreo/patología
8.
Rinsho Ketsueki ; 61(10): 1469-1475, 2020.
Artículo en Japonés | MEDLINE | ID: mdl-33162442

RESUMEN

A 45-year-old man initially diagnosed with aplastic anemia had been receiving treatment for >4 years when he visited our hospital for a detailed examination. On admission, bone marrow (BM) aspiration showed erythroid dysplasia and chromosomal abnormalities, including trisomy 3 in 1/20 cells. After 3 months of observation, BM aspiration showed the involvement of 5% abnormal lymphocytes, and flow cytometry revealed a monoclonal B-cell phenotype. After a further 5 months of observation, his blood test showed a sudden elevation in white blood cell (WBC) count and the presence of villous lymphocytes. Fluorodeoxyglucose-positron emission tomography (FDG-PET) only revealed strong uptake by systemic BM, and BM aspiration showed the involvement of 76.4% abnormal lymphocytes, which were positive for CD19 and dim CD11c; negative for CD25, CD103, cyclin D1, and BRAF-V600E; and exhibited light chain restriction. The patient was diagnosed with marginal zone lymphoma-like primary bone marrow (BM) lymphoma. Treatment with R-CHOP and R-cladribine failed. He then underwent an allogeneic peripheral blood stem cell transplantation from a human leucocyte antigen (HLA)-identical sibling, and he has since remained in good health and without relapse for 9 years. Further clinical and biological analyses are necessary to establish an optimal treatment strategy for this disease.


Asunto(s)
Neoplasias Óseas , Linfoma de Células B de la Zona Marginal , Pancitopenia , Médula Ósea , Humanos , Linfoma de Células B de la Zona Marginal/complicaciones , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Pancitopenia/complicaciones
9.
Rinsho Ketsueki ; 61(10): 1487-1491, 2020.
Artículo en Japonés | MEDLINE | ID: mdl-33162445

RESUMEN

This is a case of a 75-year-old man who was on maintenance hemodialysis for 10 years due to diabetic nephropathy and was prescribed polaprezinc due to a low serum zinc level (55 µg/dl) and dysgeusia. Three months after the polaprezinc treatment was initiated, the patient developed pancytopenia, which persisted even after the serum zinc level was normalized and medication was discontinued. He was referred to our institute so that the progression of pancytopenia could be assessed. A blood biochemical examination revealed a WBC count of 1,700/µl, Hb level of 8.9 g/dl, and Plt count of 9.5×104/µl. A bone marrow aspirate smear showed slight megaloblastic changes and ringed sideroblasts in addition to an elevated WT1 mRNA level (76 copies/µg RNA) in the peripheral blood. Although these findings mimicked those of myelodysplasia, low serum copper (<2 µg/dl) and ceruloplasmin levels (3 mg/dl) were suggestive of hematopoietic abnormalities due to zinc-induced copper deficiency. Treatment with cocoa, a compound generally known to be rich in copper, gradually improved the pancytopenia and dysplastic bone marrow histology. This case indicates that clinicians should consider the risk of zinc-induced copper deficiency and its complications when zinc supplementation is administered to patients with chronic kidney disease, particularly those undergoing hemodialysis.


Asunto(s)
Hematopoyesis , Anciano , Cobre , Suplementos Dietéticos , Humanos , Masculino , Diálisis Renal , Zinc
10.
Cancer Sci ; 110(1): 194-208, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30343511

RESUMEN

Multiple myeloma (MM) is an incurable hematological malignancy caused by accumulation of abnormal clonal plasma cells. Despite the recent development of novel therapies, relapse of MM eventually occurs as a result of a remaining population of drug-resistant myeloma stem cells. Side population (SP) cells show cancer stem cell-like characteristics in MM; thus, targeting these cells is a promising strategy to completely cure this malignancy. Herein, we showed that SP cells expressed higher levels of enhancer of zeste homolog (EZH) 1 and EZH2, which encode the catalytic subunits of Polycomb repressive complex 2 (PRC2), than non-SP cells, suggesting that EZH1 as well as EZH2 contributes to the stemness maintenance of the MM cells and that targeting both EZH1/2 is potentially a significant therapeutic approach for eradicating myeloma stem cells. A novel orally bioavailable EZH1/2 dual inhibitor, OR-S1, effectively eradicated SP cells and had a greater antitumor effect than a selective EZH2 inhibitor in vitro and in vivo, including a unique patient-derived xenograft model. Moreover, long-term continuous dosing of OR-S1 completely cured mice bearing orthotopic xenografts. Additionally, PRC2 directly regulated WNT signaling in MM, and overactivation of this signaling induced by dual inhibition of EZH1/2 eradicated myeloma stem cells and negatively affected tumorigenesis, suggesting that repression of WNT signaling by PRC2 plays an important role in stemness maintenance of MM cells. Our results show the role of EZH1/2 in the maintenance of myeloma stem cells and provide a preclinical rationale for therapeutic application of OR-S1, leading to significant advances in the treatment of MM.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Mieloma Múltiple/prevención & control , Células Madre Neoplásicas/efectos de los fármacos , Complejo Represivo Polycomb 2/antagonistas & inhibidores , Vía de Señalización Wnt/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Células Madre Neoplásicas/metabolismo , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Células de Población Lateral/efectos de los fármacos , Células de Población Lateral/metabolismo , Vía de Señalización Wnt/genética
11.
Curr Genet ; 65(2): 575-590, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30498953

RESUMEN

DNA sequences that read the same from 5' to 3' in either strand are called inverted repeat sequences or simply IRs. They are found throughout a wide variety of genomes, from prokaryotes to eukaryotes. Despite extensive research, their in vivo functions, if any, remain unclear. Using Saccharomyces cerevisiae, we performed genome-wide analyses for the distribution, occurrence frequency, sequence characteristics and relevance to chromatin structure, for the IRs that reportedly have a cruciform-forming potential. Here, we provide the first comprehensive map of these IRs in the S. cerevisiae genome. The statistically significant enrichment of the IRs was found in the close vicinity of the DNA positions corresponding to polyadenylation [poly(A)] sites and ~ 30 to ~ 60 bp downstream of start codon-coding sites (referred to as 'start codons'). In the former, ApT- or TpA-rich IRs and A-tract- or T-tract-rich IRs are enriched, while in the latter, different IRs are enriched. Furthermore, we found a strong structural correlation between the former IRs and the poly(A) signal. In the chromatin formed on the gene end regions, the majority of the IRs causes low nucleosome occupancy. The IRs in the region ~ 30 to ~ 60 bp downstream of start codons are located in the + 1 nucleosomes. In contrast, fewer IRs are present in the adjacent region downstream of start codons. The current study suggests that the IRs play similar roles in Escherichia coli and S. cerevisiae to regulate or complete transcription at the RNA level.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Secuencias Invertidas Repetidas , Nucleosomas/metabolismo , Poliadenilación , Levaduras/genética , Levaduras/metabolismo , Regiones no Traducidas 3' , Cromatina/genética , Cromatina/metabolismo , Biología Computacional/métodos , Genoma Fúngico , Genómica/métodos , Anotación de Secuencia Molecular , Unión Proteica
12.
Eur J Haematol ; 102(2): 191-196, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30390359

RESUMEN

OBJECTIVE: Primary vitreoretinal lymphoma (PVRL) is a rare type of lymphoma wherein the lesions are limited to the eyes. PVRL is difficult to diagnose because of the challenges related to obtaining sufficient samples for biopsy. Moreover, PVRL has poor outcomes and often leads to the development of central nervous system (CNS) lesions during its course. Two studies recently reported that approximately 70%-80% of patients with vitreoretinal lymphoma have MYD88L265P , which is frequently mutated in primary CNS lymphoma (PCNSL). PCNSL is closely associated with PVRL. The mutation of CD79BY196 has been also frequently detected in PCNSL. Thus, we examined the mutation in PVRL to clarify its diagnostic and prognostic potential. METHOD: By using direct sequencing and allele-specific polymerase chain reaction, we examined the mutation of CD79BY196 and MYD88L265P in the DNA extracted from the vitreous fluid of 17 patients with PVRL upon diagnosis. We also retrospectively analyzed their prognostic potential for PVRL. RESULTS: Among the included patients, six patients (35%) were found with CD79BY196 mutations. Twelve (71%) patients were positive for MYD88L265P , and six samples from patients with benign uveitis were negative for both mutations. Interestingly, six patients with CD79BY196 mutations developed CNS diseases significantly earlier (16.5 months) than 11 patients with CD79BWT (67 months; P = 0.0135). CONCLUSION: Detecting CD79BY196 in vitreous DNA may contribute to the confirmation of the diagnosis and may have a prognostic potential for patients with PVRL.


Asunto(s)
Antígenos CD79/genética , Neoplasias del Ojo/diagnóstico , Neoplasias del Ojo/genética , Linfoma/diagnóstico , Linfoma/genética , Mutación , Anciano , Anciano de 80 o más Años , Alelos , Biomarcadores de Tumor , Análisis Mutacional de ADN , Neoplasias del Ojo/mortalidad , Femenino , Humanos , Estimación de Kaplan-Meier , Linfoma/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Cuerpo Vítreo/metabolismo , Cuerpo Vítreo/patología
13.
Rinsho Ketsueki ; 60(1): 7-11, 2019.
Artículo en Japonés | MEDLINE | ID: mdl-30726827

RESUMEN

A 54-year-old female complained of oral erosion. A flaccid blister appeared on the trunk 2 months after the onset. The high titer of the anti-desmoglein 1 antibody in the absence of Nikolsky's sign led to the diagnosis of pemphigus vulgaris. The lymphadenopathy in the mesenteric and para-aortic regions indicated the possibility of paraneoplastic pemphigus. The steroid pulse therapy and therapeutic plasma exchange were ineffective. As CT-guided intraperitoneal lymph node biopsy revealed follicular lymphoma, R-CHOP therapy was performed. Although partial remission was attained accompanied by an improvement in the skin and mucosal findings after four courses of R-CHOP therapy, an occlusive ventilatory disturbance, possibly attributed to bronchiolitis obliterans, appeared 4 months after the treatment initiation. Although the treatment with tacrolimus was attempted, it was not feasible to be continued because of opportunistic infection, and the patient died 9 months after the onset of the skin lesion. Although specific anti-plakin antibodies were negative, this case was diagnosed as paraneoplastic pemphigus due to follicular lymphoma and complicated by obstructive bronchiolitis based on the clinical findings. The accumulation of similar cases is needed to establish effective treatment strategies.


Asunto(s)
Bronquiolitis Obliterante/diagnóstico , Linfoma Folicular/diagnóstico , Síndromes Paraneoplásicos/diagnóstico , Pénfigo/diagnóstico , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Prednisona/uso terapéutico , Rituximab , Vincristina/uso terapéutico
14.
J Biol Chem ; 292(48): 19639-19655, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28974577

RESUMEN

Platelet endothelial cell adhesion molecule 1 (PECAM-1) is a cell adhesion protein involved in the regulation of cell adhesion and migration. Interestingly, several PECAM-1-deficient hematopoietic cells exhibit impaired chemotactic responses to stromal cell-derived factor 1 (SDF-1), a chemokine essential for B lymphopoiesis and bone marrow myelopoiesis. However, whether PECAM-1 is involved in SDF-1-regulated chemotaxis is unknown. We report here that SDF-1 induces tyrosine phosphorylation of PECAM-1 at its immunoreceptor tyrosine-based inhibition motifs in several hematopoietic cell lines via the Src family kinase Lyn, Bruton's tyrosine kinase, and JAK2 and that inhibition of these kinases reduced chemotaxis. Overexpression and knockdown of PECAM-1 enhanced and down-regulated, respectively, SDF-1-induced Gαi-dependent activation of the PI3K/Akt/mTORC1 pathway and small GTPase Rap1 in hematopoietic 32Dcl3 cells, and these changes in activation correlated with chemotaxis. Furthermore, pharmacological or genetic inhibition of the PI3K/Akt/mTORC1 pathway or Rap1, respectively, revealed that these pathways are independently activated and required for SDF-1-induced chemotaxis. When coexpressed in 293T cells, PECAM-1 physically associated with the SDF-1 receptor CXCR4. Moreover, PECAM-1 overexpression and knockdown reduced and enhanced SDF-1-induced endocytosis of CXCR4, respectively. Furthermore, when expressed in 32Dcl3 cells, an endocytosis-defective CXCR4 mutant, CXCR4-S324A/S325A, could activate the PI3K/Akt/mTORC1 pathway as well as Rap1 and induce chemotaxis in a manner similar to PECAM-1 overexpression. These findings suggest that PECAM-1 enhances SDF-1-induced chemotaxis by augmenting and prolonging activation of the PI3K/Akt/mTORC1 pathway and Rap1 and that PECAM-1, at least partly, exerts its activity by inhibiting SDF-1-induced internalization of CXCR4.


Asunto(s)
Quimiocina CXCL12/fisiología , Leucocitos/fisiología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/fisiología , Animales , Células de la Médula Ósea/metabolismo , Línea Celular , Ratones , Fosforilación , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/química , Proteínas Tirosina Quinasas/metabolismo , Receptores CXCR4/metabolismo , Tirosina/metabolismo
15.
Lab Invest ; 98(5): 609-619, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29463878

RESUMEN

Regulation of oxidative stress and redox systems has important roles in carcinogenesis and cancer progression, and for this reason has attracted much attention as a new area of cancer therapeutic targets. Glutathione peroxidase 4 (GPX4), an antioxidant enzyme, has biological important functions such as signaling cell death by suppressing peroxidation of membrane phospholipids. However, few studies exist on the expression and clinical relevance of GPX4 in malignant lymphomas such as diffuse large B-cell lymphoma. In this study, we assessed the expression of GPX4 immunohistochemically. GPX4 was expressed in 35.5% (33/93) cases of diffuse large B-cell lymphoma. The GPX4-positive group had poor overall survival (P = 0.0032) and progression-free survival (P = 0.0004) compared with those of the GPX4-negative group. In a combined analysis of GPX4 and 8-hydroxydeoxyguanosine (8-OHdG), an oxidative stress marker, there was a negative correlation between GPX4 and 8-hydroxydeoxyguanosine (P = 0.0009). The GPX4-positive and 8-hydroxydeoxyguanosine-negative groups had a significantly worse prognosis than the other groups in both overall survival (P = 0.0170) and progression-free survival (P = 0.0005). These results suggest that the overexpression of GPX4 is an independent prognostic predictor in diffuse large B-cell lymphoma. Furthermore, in vitro analysis demonstrated that GPX4-overexpressing cells were resistant to reactive oxygen species-induced cell death (P = 0.0360). Conversely, GPX4-knockdown cells were sensitive to reactive oxygen species-induced cell death (P = 0.0111). From these data, we conclude that GPX4 regulates reactive oxygen species-induced cell death. Our results suggest a novel therapeutic strategy using the mechanism of ferroptosis, as well as a novel prognostic predictor of diffuse large B-cell lymphoma.


Asunto(s)
Apoptosis , Glutatión Peroxidasa/fisiología , Linfoma de Células B Grandes Difuso/patología , Especies Reactivas de Oxígeno/metabolismo , 8-Hidroxi-2'-Desoxicoguanosina , Células Cultivadas , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análisis , Glutatión Peroxidasa/análisis , Glutatión Peroxidasa/genética , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/enzimología , Linfoma de Células B Grandes Difuso/mortalidad , Fosfolípido Hidroperóxido Glutatión Peroxidasa
16.
Curr Genet ; 64(4): 945-958, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29484452

RESUMEN

Inverted repeat (IR) sequences are DNA sequences that read the same from 5' to 3' in each strand. Some IRs can form cruciforms under the stress of negative supercoiling, and these IRs are widely found in genomes. However, their biological significance remains unclear. The aim of the current study is to explore this issue further. We constructed the first Escherichia coli genome-wide comprehensive map of IRs with cruciform-forming potential. Based on the map, we performed detailed and quantitative analyses. Here, we report that IRs with cruciform-forming potential are statistically enriched in the following five regions: the adjacent regions downstream of the stop codon-coding sites (referred to as the stop codons), on and around the positions corresponding to mRNA ends (referred to as the gene ends), ~ 20 to ~45 bp upstream of the start codon-coding sites (referred to as the start codons) within the 5'-UTR (untranslated region), ~ 25 to ~ 60 bp downstream of the start codons, and promoter regions. For the adjacent regions downstream of the stop codons and on and around the gene ends, most of the IRs with a repeat unit length of ≥ 8 bp and a spacer size of ≤ 8 bp were parts of the intrinsic terminators, regardless of the location, and presumably used for Rho-independent transcription termination. In contrast, fewer IRs were present in the small region preceding the start codons. In E. coli, IRs with cruciform-forming potential are actively placed or excluded in the regulatory regions for the initiation and termination of transcription and translation, indicating their deep involvement or influence in these processes.


Asunto(s)
ADN Cruciforme/genética , Escherichia coli/genética , Genoma Bacteriano/genética , Secuencias Invertidas Repetidas/genética , Regiones no Traducidas 5'/genética , Secuencia de Bases/genética , Codón de Terminación/genética
17.
Curr Genet ; 64(5): 1171, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30136148

RESUMEN

The article 'Requirement or exclusion of inverted repeat sequences with cruciform-forming potential in Escherichia coli revealed by genome-wide analyses' written by Osamu Miura, Toshihiro Ogake, Takashi Ohyama was originally published online on SpringerLink with open access.

18.
Rinsho Ketsueki ; 59(12): 2555-2560, 2018.
Artículo en Japonés | MEDLINE | ID: mdl-30626788

RESUMEN

A 24-year-old male patient with T-cell acute lymphoblastic leukemia was diagnosed with severe hypertriglyceridemia after the sixth administration of L-asparaginase during remission-induction therapy of the Japan Adult Leukemia Study Group (JALSG) -ALL 202-U protocol. Lipoprotein analysis revealed type IV hyperlipidemia, which is associated with a relatively low risk for pancreatitis. Hypertriglyceridemia immediately resolved after discontinuing L-asparaginase and beginning a lipid-restricted diet. The patient did not develop any severe complications of hypertriglyceridemia (e.g., pancreatitis and thrombosis) ; therefore, L-asparaginase could be readministered according to the treatment protocol. Four adult patients with L-asparaginase-induced severe hypertriglyceridemia have been reported to date; however, none of the reports indicated that L-asparaginase had been readministered. Thus, this is the first report of a patient receiving such readministeration. In order to evaluate the safety of continuing L-asparaginase, it is considered necessary to accumulate similar readministration cases.


Asunto(s)
Asparaginasa/efectos adversos , Asparaginasa/uso terapéutico , Hipertrigliceridemia/inducido químicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adulto , Antineoplásicos/efectos adversos , Humanos , Hipertrigliceridemia/complicaciones , Japón , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Adulto Joven
19.
Rinsho Ketsueki ; 59(4): 367-372, 2018.
Artículo en Japonés | MEDLINE | ID: mdl-29743394

RESUMEN

As chronic active Epstein-Barr virus (EBV) infection (CAEBV) progresses, EBV-infected tumor cells invade the central nervous system (CNS). To establish a diagnostic procedure for CNS invasion, we retrospectively analyzed cerebrospinal fluid (CSF) obtained from eight patients. Two patients presented with consciousness disturbance and were diagnosed with CNS invasion based on scan and autopsy results, respectively. The remaining six patients were diagnosed without CNS invasion by clinical findings and scans. In the two patients with CNS invasion, the number of mononuclear cells and the protein concentration were increased, whereas the CSF to serum glucose ratio and the adenosine deaminase concentration were raised. In one of the two patients, however, bacterial meningitis could not be excluded. Cytological examination of CSF demonstrated class 1-3. Notably, the CSF EBV-DNA load was positive in all patients, independent of CNS invasion diagnosis, and the CSF load correlated with that of the peripheral blood. Taken together, this indicates that CSF may lack the specific markers of CNS invasion in CAEBV patients. The CSF EBV-DNA load and the cytological analysis did not reflect CNS invasion; therefore, new biomarkers need to be established.


Asunto(s)
Enfermedades del Sistema Nervioso Central/virología , Infecciones por Virus de Epstein-Barr/líquido cefalorraquídeo , Herpesvirus Humano 4 , ADN Viral/líquido cefalorraquídeo , Humanos , Estudios Retrospectivos , Carga Viral
20.
Ecology ; 98(9): 2241-2247, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28722104

RESUMEN

Nonnative species that escape their native-range parasites may benefit not only from reduced infection pathology, but also from relaxed selection on costly immune defenses, promoting reallocation of resources toward growth or reproduction. However, benefits accruing from a reduction in defense could come at the cost of increased infection susceptibility. We conducted common garden studies of the shore crab Hemigrapsus sanguineus from highly parasitized native (Japan) populations and largely parasite-free invasive (USA) populations to test for differences in susceptibility to infection by native-range rhizocephalan parasites, and to explore differences in host resource allocation. Nonnative individuals showed at least 1.8 times greater susceptibility to infection than their native counterparts, and had reduced standing metabolic rates, suggesting that less of their energy was spent on physiological self-maintenance. Our results support an indirect advantage to parasite escape via the relaxation of costly physiological defenses. However, this advantage comes at the cost of heightened susceptibility, a trade-off of parasite escape that is seldom considered.


Asunto(s)
Braquiuros/fisiología , Interacciones Huésped-Parásitos , Animales , Japón , Parásitos
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