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1.
Sao Paulo Med J ; 142(4): e20230142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38477775

RESUMO

CONTEXT: Scrub typhus, caused by Orientia tsutsugamushi, has a wide range of clinical manifestations, including meningoencephalitis, acute renal failure, pneumonitis, myocarditis, and septic shock. However, there are no documented cases of scrub typhus with hypokalemia. In this report, we present a case of scrub typhus with hypokalemia and multiple organ failure syndrome, highlighting the importance of electrolyte imbalance in patients with scrub typhus. CASE REPORT: A 59-year-old woman presented to the emergency department with abdominal pain that had been present for 1 day. On admission, the physical examination and laboratory test results indicated that the patient had renal, liver, and circulatory failure, and hypokalemia. She developed meningitis and disseminated intravascular coagulation during hospitalization. She recovered with appropriate management, and was discharged on day 17. CONCLUSION: This report highlights the potential for atypical presentations of scrub typhus, including a previously undocumented association with hypokalemia. Although the contribution of hypokalemia to the patient's clinical course remains uncertain, this case underscores the importance of considering electrolyte imbalance in the management of patients with scrub typhus. Further research is warranted to better understand the relationship between scrub typhus and electrolyte imbalance.


Assuntos
Hipopotassemia , Tifo por Ácaros , Choque Séptico , Feminino , Humanos , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos , Eletrólitos
2.
São Paulo med. j ; 142(4): e20230142, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1551077

RESUMO

ABSTRACT CONTEXT: Scrub typhus, caused by Orientia tsutsugamushi, has a wide range of clinical manifestations, including meningoencephalitis, acute renal failure, pneumonitis, myocarditis, and septic shock. However, there are no documented cases of scrub typhus with hypokalemia. In this report, we present a case of scrub typhus with hypokalemia and multiple organ failure syndrome, highlighting the importance of electrolyte imbalance in patients with scrub typhus. CASE REPORT: A 59-year-old woman presented to the emergency department with abdominal pain that had been present for 1 day. On admission, the physical examination and laboratory test results indicated that the patient had renal, liver, and circulatory failure, and hypokalemia. She developed meningitis and disseminated intravascular coagulation during hospitalization. She recovered with appropriate management, and was discharged on day 17. CONCLUSION: This report highlights the potential for atypical presentations of scrub typhus, including a previously undocumented association with hypokalemia. Although the contribution of hypokalemia to the patient's clinical course remains uncertain, this case underscores the importance of considering electrolyte imbalance in the management of patients with scrub typhus. Further research is warranted to better understand the relationship between scrub typhus and electrolyte imbalance.

4.
J Cancer Res Clin Oncol ; 149(5): 1941-1950, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35896898

RESUMO

BACKGROUND: Circulating tumour cells (CTCs) are attractive "liquid biopsy" candidates that could provide insights into the different phenotypes of tumours present within a patient. The epithelial-to-mesenchymal transition (EMT) of CTCs is considered a critical step in tumour metastasis; however, it may confound traditional epithelial feature-based CTC isolation and detection. We applied single-cell copy number alteration (CNA) analysis for the identification of genomic alterations to confirm the neoplastic nature of circulating cells with only mesenchymal phenotypes. METHODS: We isolated CTCs from blood samples collected from 46 NSCLC patients using the Parsortix system. Enriched cells were subjected to immunofluorescent staining for CTC identification using a multi-marker panel comprising both epithelial and mesenchymal markers. A subset of isolated CTCs was subjected to whole genome amplification (WGA) and low-pass whole-genome sequencing (LP-WGS) for the analysis of copy number alterations (CNAs). RESULTS: CTCs were detected in 16/46 (34.8%) patients, inclusive of CK+/EpCAM+ CTCs (3/46, 6.5%) and Vim+ CTCs (13/46, 28.3%). Clusters of Vim+ cells were detected in 8 samples, which constitutes 50% of the total number of NSCLC patients with CTCs. No patients had detectable hybrid CK+/EpCAM+/Vim+ cells. All of the tested CK+/EpCAM+ CTCs and 7/8 Vim+ CTCs or CTC clusters carried CNAs confirming their neoplastic nature. Notably, the Vim+ cluster with no CNAs was characterised by spindle morphology and, therefore, defined as normal mesenchymal circulating cells. CONCLUSION: Our results revealed that CK-negative, vimentin-expressing cells represent a large proportion of CTCs detected in NSCLC patients, which are likely missed by standard epithelial-marker-dependent CTC categorisation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Molécula de Adesão da Célula Epitelial , Neoplasias Pulmonares/patologia , Transição Epitelial-Mesenquimal/genética , Genômica , Biomarcadores Tumorais/análise
5.
Transl Lung Cancer Res ; 11(3): 440-451, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35399573

RESUMO

Background: Antibodies against the programmed death-1 (PD-1) receptor and its ligand (PD-L1) have been recently approved for small-cell lung cancer (SCLC) treatment. Circulating tumour cells (CTCs) have emerged as an appealing liquid biopsy candidate that could enhance treatment decision-making in systemic therapy for SCLC patients. Several current technologies enrich CTCs using specific surface epitopes, size, rigidity, or dielectric properties. However, they are hampered by the heterogeneity of the enriched cells from blood samples. Methods: We evaluated two CTC enrichment systems: EpCAM conjugated to magnetic beads and a microfluidic device (Parsortix, Angle plc). PD-L1 expression was evaluated on the isolated CTCs. Twenty-three blood samples were collected from 21 patients with SCLC. PD-L1 expression was determined on CTCs through immunofluorescent staining. Results: CTCs were found in 14/23 (60.9%) of the samples, with 11/23 (47.8%) through EpCAM-coated magnetic beads (range, 4-1,611 CTCs/8 mL; median =5) and 11/20 (55.0%) using the Parsortix system (range, 1-165 CTCs/8 mL; median =4). Notably, a total of 17 EpCAM-negative CTCs were isolated using the Parsortix system. PD-L1 expression was detected on 268 of the 3,501 (7.7%) CTCs isolated with EpCAM-coated beads and in 33/366 (9.0%) of the CTCs isolated with the Parsortix system. No vimentin expression was observed in any of the detected CTCs. Conclusions: Overall, we identified a population of EpCAM-negative SCLC CTCs and showed that PD-L1 expression can be assessed on CTCs from SCLC patients. Comparison to tumour and treatment outcomes is needed to validate the potential of CTCs as an alternative sample for the assessment of PD-L1 expression in SCLC.

6.
Cancers (Basel) ; 13(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34944844

RESUMO

Detection of ovarian cancer (OC) circulating tumour cells (CTCs) is primarily based on targeting epithelial markers, thus failing to detect mesenchymal tumour cells. More importantly, the immune checkpoint inhibitor marker PD-L1 has not been demonstrated on CTCs from OC patients. An antibody staining protocol was developed and tested using SKOV-3 and OVCA432 OC cell lines. We targeted epithelial (cytokeratin (CK) and EpCAM), mesenchymal (vimentin), and OC-specific (PAX8) markers for detection of CTCs, and CD45/16 and CD31 were used for the exclusion of white blood and vascular endothelial cells, respectively. PD-L1 was used for CTC characterisation. CTCs were enriched using the Parsortix™ system from 16 OC patients. Results revealed the presence of CTCs in 10 (63%) cases. CTCs were heterogeneous, with 113/157 (72%) cells positive for CK/EpCAM (epithelial marker), 58/157 (37%) positive for vimentin (mesenchymal marker), and 17/157 (11%) for both (hybrid). PAX8 was only found in 11/157 (7%) CTCs. In addition, 62/157 (39%) CTCs were positive for PD-L1. Positivity for PD-L1 was significantly associated with the hybrid phenotype when compared with the epithelial (p = 0.007) and mesenchymal (p = 0.0009) expressing CTCs. Characterisation of CTC phenotypes in relation to clinical outcomes is needed to provide insight into the role that epithelial to mesenchymal plasticity plays in OC and its relationship with PD-L1.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34470851

RESUMO

Tumor heterogeneity is a major obstacle to the success of cancer treatment. An accurate understanding and recognition of tumor heterogeneity is critical in the clinical management of cancer patients. Here, we utilized single-cell RNA sequencing (scRNA-seq) to uncover the intra- and intertumoral heterogeneity of liver metastases from a patient with metastatic uveal melanoma. The two metastases analyzed were largely infiltrated by noncancerous cells with significant variability in the proportion of different cell types. Analysis of copy-number variations (CNVs) showed gain of 8q and loss of 6q in both tumors, but loss of Chromosome 3 was only detected in one of the tumors. Single-nucleotide polymorphism (SNP) array revealed a uniparental isodisomy 3 in the tumor with two copies of Chromosome 3, indicating a regain of Chromosome 3 during the development of the metastatic disease. In addition, both tumors harbored subclones with additional CNVs. Pathway enrichment analysis of differentially expressed genes revealed that cancer cells in the metastasis with isodisomy 3 showed up-regulation in epithelial-mesenchymal transition and myogenesis related genes. In contrast, up-regulation in interferon signaling was observed in the metastasis with monosomy 3 and increased T-cell infiltrate. This study highlights the complexity and heterogeneity of different metastases within an individual case of uveal melanoma.


Assuntos
Neoplasias Hepáticas , Melanoma , Neoplasias Uveais , Humanos , Neoplasias Hepáticas/genética , Melanoma/genética , Análise de Sequência de RNA , Neoplasias Uveais/genética
8.
Appl Opt ; 60(5): 1470-1475, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33690593

RESUMO

Speckle reduction is a crucial technique since the presence of speckle disturbs the quality of the reconstruction in digital holography. In this paper, we present an easy, fast, and efficient single-shot method to reduce speckle noise in digital holography. The method reconstructs subholograms from a single hologram. Then, sub-reconstruction images are randomly shuffled and divided into several groups and low-dimensional noise-reduced images can be achieved by averaging sub-reconstruction image groups by groups. Next, these low-dimensional noise-reduced images are combined to obtain a noise-reduced image. Finally, the noise-reduced image is processed by a mean filter to obtain a final image, which has substantially less speckle noise while preserving the dimensions of the original image. The experimental results demonstrate the effectiveness of the proposed method and indicate its potential in real-time digital holography.

9.
Methods Mol Biol ; 2265: 213-222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704717

RESUMO

Within the last decade, circulating tumor cells (CTCs) have emerged as a promising biomarker for prognostication, treatment monitoring, and detection of markers of treatment resistance, and their isolation can be used as a minimally invasive means of profiling tumors across multiple body sites. However, CTCs represent a minuscule fraction of the total circulating cells in a patient. Therefore, sensitive isolation methods are needed for the detection and downstream analysis of these cells. Herein we describe a sensitive method for melanoma CTC isolation using a multi-marker immunomagnetic bead method. This method has been purposely optimized to detect CTCs in melanoma patients.


Assuntos
Antígenos de Neoplasias/imunologia , Separação Imunomagnética/métodos , Leucócitos Mononucleares/metabolismo , Melanoma/sangue , Antineoplásicos Imunológicos/imunologia , Biomarcadores Tumorais/metabolismo , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Melanoma/metabolismo , Melanoma/patologia , Células Neoplásicas Circulantes
10.
Methods Mol Biol ; 2265: 235-245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704719

RESUMO

Circulating tumor cells (CTCs) are cancer cells shed by the primary tumor or its metastases that circulate in the peripheral blood. CTCs are potential seeds for metastases, and their detection may allow early uncovering of metastatic dissemination and disease prognostication. To fully ascertain the biomarker potential of melanoma CTCs, sensitive and reliable methods are required. Melanoma-specific transcript analysis has been widely utilized as a standard approach for measuring the presence of CTCs. Here we describe a method for the analysis of CTCs through the detection of specific transcripts in CTC-enriched fractions.


Assuntos
Biomarcadores Tumorais/sangue , Melanoma/sangue , Células Neoplásicas Circulantes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Biomarcadores Tumorais/genética , DNA/sangue , DNA/isolamento & purificação , Humanos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patologia , Células Neoplásicas Circulantes/patologia , RNA/sangue , RNA/isolamento & purificação
11.
Cells ; 9(11)2020 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142852

RESUMO

: Antibodies against programmed death-1 (PD-1), and its ligand, (PD-L1) have been approved recently for the treatment of small-cell lung cancer (SCLC). Although there are previous reports that addressed PD-L1 detection on tumour cells in SCLC, there is no comprehensive meta-analysis on the prevalence of PD-L1 expression in SCLC. We performed a systematic search of the PubMed, Cochrane Library and EMBASE databases to assess reports on the prevalence of PD-L1 expression and the association between PD-L1 expression and overall survival (OS). This meta-analysis included 27 studies enrolling a total of 2792 patients. The pooled estimate of PD-L1 expression was 26.0% (95% CI 17.0-37.0), (22.0% after removing outlying studies). The effect size was significantly heterogeneous (I2 = 97.4, 95% CI: 95.5-98.5, p < 0.0001).Positive PD-L1 expression was a favourable prognostic factor for SCLC but not statistically significant (HR = 0.86 (95% CI (0.49-1.50), p = 0.5880; I2 = 88.7%, p < 0.0001). Begg's funnel plots and Egger's tests indicated no publication bias across included studies (p > 0.05). Overall, there is heterogeneity in the prevalence of PD-L1 expression in SCLC tumour cells across studies. This is significantly moderated by factors such as immunohistochemistry (IHC) evaluation cut-off values, and assessment of PD-L1 staining patterns as membranous and/or cytoplasmic. There is the need for large size, prospective and multicentre studies with well-defined protocols and endpoints to advance the clinical value of PD-L1 expression in SCLC.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/metabolismo , Carcinoma de Pequenas Células do Pulmão/metabolismo , Antígeno B7-H1/genética , Ensaios Clínicos como Assunto , Humanos , Neoplasias Pulmonares/genética , Estudos Prospectivos , Carcinoma de Pequenas Células do Pulmão/genética , Análise de Sobrevida
12.
Appl Opt ; 59(16): 5066-5072, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32543505

RESUMO

Speckle reduction is a crucial technique, since the presence of speckle disturbs the quality of the reconstruction in digital holography. In this paper, we present a redundant speckle elimination method to suppress the speckle noise. For the same position in each of the reconstructed sub-images, we consider pixels with the same gray value as information with the same speckle distribution. Therefore, a speckle-suppressed gray value can be obtained by extracting pixels with different gray values and then averaging. Through theoretical analysis and experiments, we demonstrate that speckle contrast can be decreased significantly by using the proposed method. Moreover, we show that the despeckle strength of the proposed method highly depends on the number of binary masks. These results indicate the potential of the proposed method for various applications.

13.
Appl Opt ; 59(5): 1484-1490, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32225407

RESUMO

Herein, multiple Fano resonances with excellent ability to be tuned independently are produced in a sub-wavelength metal-insulator-metal system. The input and output waveguides are separated by a metal gap, and a stub and an end-coupled cavity are placed below and to the right side of the input waveguide, respectively, as discrete states. Owing to the mode interferences, double ultra-sharp and asymmetric Fano resonant peaks are observed in the transmission spectrum. Successfully, the basic structure is extended by two extra rectangular cavities, giving rise to four Fano resonances with high refractive index sensitivity and figure of merit. Due to the discrete modes of Fano resonances from different coupling cavities, their resonant wavelengths can be controlled independently, which can provide greater flexibility for tuning Fano resonances. The performances of the proposed structure are investigated by both the finite-difference time-domain method and the multimode interference coupled-mode theory. It is believed that the research can provide important guidance in designing Fano resonance structures, and the proposed structure has a wide application in sensors, switches, and nano-photonic integrated circuit devices.

14.
Cancers (Basel) ; 11(7)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31262041

RESUMO

Anti-programmed cell death (PD)-1/PD-ligand 1 (L1) therapies have significantly improved the outcomes for non-small cell lung cancer (NSCLC) patients in recent years. These therapies work by reactivating the immune system and enabling it to target cancer cells once more. There is a general agreement that expression of PD-L1 on tumour cells predicts the therapeutic response to PD-1/PD-L1 inhibitors in NSCLC. Hence, immunohistochemical staining of tumour tissue biopsies from NSCLC patients with PD-L1 antibodies is the current standard used to aid selection of patients for treatment with anti-PD-1 as first line therapy. However, issues of small tissue samples, tissue heterogeneity, the emergence of new metastatic sites, and dynamic changes in the expression of PD-L1 may influence PD-L1 status during disease evolution. Re-biopsy would expose patients to the risk of complications and tardy results. Analysis of PD-L1 expression on circulating tumour cells (CTCs) may provide an accessible and non-invasive means to select patients for anti-PD-1 therapies. Additionally, CTCs could potentially provide a useful biomarker in their own right. Several published studies have assessed PD-L1 expression on CTCs from NSCLC patients. Overall, analysis of PD-L1 on CTCs is feasible and could be detected prior to and after frontline therapy. However, there is no evidence on whether PD-L1 expression on CTCs could predict the response to anti-PD-1/PD-L1 treatment. This review examines the challenges that need to be addressed to demonstrate the clinical validity of PD-L1 analysis in CTCs as a biomarker capable of predicting the response to immune checkpoint blockade.

15.
J Gen Virol ; 100(6): 999-1012, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30816843

RESUMO

Epstein-Barr virus (EBV) infection is strongly associated with nasopharyngeal carcinoma, a common cancer in Southeast Asia and certain regions of Africa. However, the dynamics of EBV episome maintenance in infected nasopharyngeal epithelial (NPE) cells remain largely undefined. Here, we report the establishment of a highly efficient cell-free EBV infection method for NPE cells. By using this method, we have defined some of the dynamic events involved in the early stage of EBV infection in NPE cells. We report, for the first time, a rapid loss of EBV copies from infected NPE cells during the first 12-72 h post-infection. The rate of EBV loss slowed at later stages of infection. Live cell imaging revealed that the freshly infected NPE cells were delayed in entry into mitosis compared with uninfected cells. Freshly infected NPE cells transcribed significantly higher levels of lytic EBV genes BZLF1 and BMRF1 yet significantly lower levels of EBER1/2 than stably infected NPE cells. Notably, there were very low or undetectable levels of protein expressions of EBNA1, LMP1, Zta and Rta in freshly infected NPE cells, whereas EBNA1 and LMP1 proteins were readily detected in stable EBV-infected NPE cells. The kinetics of EBV loss and the differential EBV gene expression profiles between freshly and stably infected NPE cells are in line with the suggestion of epigenetic changes in the EBV genome that affect viral gene expression and the adaptation of host cells to EBV infection to maintain persistent EBV infection in NPE cells.


Assuntos
Células Epiteliais/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Nasofaringe/virologia , Linhagem Celular , Epigênese Genética/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Humanos , Transativadores/genética , Transcriptoma/genética
16.
Oncogene ; 38(24): 4669-4684, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30745576

RESUMO

EBV infection of preinvasive nasopharyngeal epithelium is believed to be an initiation step during pathogenesis of nasopharyngeal carcinoma (NPC), but the mechanisms remain poorly understood. Here we report a novel mechanism driving NPC metastasis through the EBV-encoded LMP1-mediated metabolic reprogramming, via activation of IGF1-mTORC2 signaling and nuclear acetylation of the Snail promoter by the PDHE1α, an enzyme involved in glucose metabolism. Mechanistically, EBV-LMP1 increases the cellular secretion of IGF1 which promotes phosphorylation of IGF1R to activate mTORC2/AKT signaling linking glucose metabolism to cell motility. LMP1 expression facilitates translocation of mitochondrial PDHE1α into the nucleus in a phosphorylation-dependent manner at Ser293 residue. Functionally, nuclear PDHE1α promotes H3K9 acetylation on the Snail promoter to enhance cell motility, thereby driving cancer metastasis. Importantly, the IGF1/mTORC2/PDHE1α/Snail axis correlates significantly with disease progression and poor prognosis in NPC patients. This study highlights the functional importance of IGF1-mTORC2-PDHE1α signaling mediated by EBV-LMP1 in NPC pathogenesis.


Assuntos
Núcleo Celular/metabolismo , Glucose/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Piruvato Desidrogenase (Lipoamida)/metabolismo , Proteínas da Matriz Viral/fisiologia , Transporte Ativo do Núcleo Celular/genética , Animais , Proliferação de Células/genética , Transformação Celular Viral/fisiologia , Células Cultivadas , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Glicólise/genética , Herpesvirus Humano 4/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/virologia , Metástase Neoplásica , Transporte Proteico , Piruvato Desidrogenase (Lipoamida)/genética , Transdução de Sinais/genética
17.
Nat Commun ; 9(1): 4663, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405107

RESUMO

The lack of representative nasopharyngeal carcinoma (NPC) models has seriously hampered research on EBV carcinogenesis and preclinical studies in NPC. Here we report the successful growth of five NPC patient-derived xenografts (PDXs) from fifty-eight attempts of transplantation of NPC specimens into NOD/SCID mice. The take rates for primary and recurrent NPC are 4.9% and 17.6%, respectively. Successful establishment of a new EBV-positive NPC cell line, NPC43, is achieved directly from patient NPC tissues by including Rho-associated coiled-coil containing kinases inhibitor (Y-27632) in culture medium. Spontaneous lytic reactivation of EBV can be observed in NPC43 upon withdrawal of Y-27632. Whole-exome sequencing (WES) reveals a close similarity in mutational profiles of these NPC PDXs with their corresponding patient NPC. Whole-genome sequencing (WGS) further delineates the genomic landscape and sequences of EBV genomes in these newly established NPC models, which supports their potential use in future studies of NPC.


Assuntos
Herpesvirus Humano 4/fisiologia , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/virologia , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Genes Virais , Herpesvirus Humano 4/genética , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Mutação/genética , Carcinoma Nasofaríngeo/genética , Filogenia , Inibidores de Proteínas Quinases/farmacologia , Vírion/metabolismo , Ativação Viral/efeitos dos fármacos , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo
18.
Lab Invest ; 98(8): 1093-1104, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29769697

RESUMO

Epstein-Barr virus (EBV) infects more than 90% of the adult human population. Undifferentiated nasopharyngeal carcinoma (NPC) is common in Southeast Asia, with a particularly high incidence among southern Chinese. The EBV genome can be detected in practically all cancer cells in undifferentiated NPC. The role of EBV in pathogenesis of undifferentiated NPC remains elusive. NPC cell lines are known to be difficult to establish in culture. The EBV+ve NPC cell lines, even if established in culture, rapidly lost their EBV episomes upon prolonged propagation. At present, the C666-1 NPC cell line, which is defective in lytic EBV reactivation, is the only EBV+ve NPC cell line available for NPC and EBV research. The need to establish new and representative NPC cell lines is eminent for NPC and EBV research. In this study, we report the use of the Rho-associated kinase inhibitor (Y-27632) has facilitated the establishment of a new EBV+ve NPC cell line from an earlier established NPC xenograft, C17. The C17 cell line was tumorigenic in immune-deficient mice (NOD/SCID). It retained the EBV episomes and could be induced to undergo productive lytic reactivation of EBV to generate infectious virus particles. The C17 cell line represents a new investigative tool for NPC and EBV studies. The ability of C17 to undergo lytic reactivation is unique and opens up the opportunity to examine regulation of latent and lytic infection of EBV and their contributions to NPC pathogenesis.


Assuntos
Infecções por Vírus Epstein-Barr/patologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Ativação Viral , Animais , Linhagem Celular Tumoral , Infecções por Vírus Epstein-Barr/virologia , Genoma Viral/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Cariotipagem , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/virologia , Transplante Heterólogo , Carga Tumoral
19.
J Virol ; 91(6)2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28053105

RESUMO

Accumulating evidence indicates that oncogenic viral protein plays a crucial role in activating aerobic glycolysis during tumorigenesis, but the underlying mechanisms are largely undefined. Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is a transmembrane protein with potent cell signaling properties and has tumorigenic transformation property. Activation of NF-κB is a major signaling pathway mediating many downstream transformation properties of LMP1. Here we report that activation of mTORC1 by LMP1 is a key modulator for activation of NF-κB signaling to mediate aerobic glycolysis. NF-κB activation is involved in the LMP1-induced upregulation of glucose transporter 1 (Glut-1) transcription and growth of nasopharyngeal carcinoma (NPC) cells. Blocking the activity of mTORC1 signaling effectively suppressed LMP1-induced NF-κB activation and Glut-1 transcription. Interfering NF-κB signaling had no effect on mTORC1 activity but effectively altered Glut-1 transcription. Luciferase promoter assay of Glut-1 also confirmed that the Glut-1 gene is a direct target gene of NF-κB signaling. Furthermore, we demonstrated that C-terminal activating region 2 (CTAR2) of LMP1 is the key domain involved in mTORC1 activation, mainly through IKKß-mediated phosphorylation of TSC2 at Ser939 Depletion of Glut-1 effectively led to suppression of aerobic glycolysis, inhibition of cell proliferation, colony formation, and attenuation of tumorigenic growth property of LMP1-expressing nasopharyngeal epithelial (NPE) cells. These findings suggest that targeting the signaling axis of mTORC1/NF-κB/Glut-1 represents a novel therapeutic target against NPC.IMPORTANCE Aerobic glycolysis is one of the hallmarks of cancer, including NPC. Recent studies suggest a role for LMP1 in mediating aerobic glycolysis. LMP1 expression is common in NPC. The delineation of essential signaling pathways induced by LMP1 in aerobic glycolysis contributes to the understanding of NPC pathogenesis. This study provides evidence that LMP1 upregulates Glut-1 transcription to control aerobic glycolysis and tumorigenic growth of NPC cells through mTORC1/NF-κB signaling. Our results reveal novel therapeutic targets against the mTORC1/NF-κB/Glut-1 signaling axis in the treatment of EBV-infected NPC.


Assuntos
Transportador de Glucose Tipo 1/biossíntese , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Complexos Multiproteicos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteínas da Matriz Viral/metabolismo , Linhagem Celular , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Transcrição Gênica
20.
Mol Vis ; 18: 989-95, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22550392

RESUMO

PURPOSE: To identify a disease-causing paired box 6 (PAX6) gene mutation in a Chinese family affected by autosomal dominant congenital aniridia. METHODS: All participants in the study, including the aniridia family and 100 unrelated senile cataract controls, received a comprehensive ophthalmic examination. Genomic DNA was extracted from their whole blood. Mutation screen in all exons and their adjacent splicing junctions of PAX6 was performed by direct sequencing of polymerase chain reaction (PCR) products. PCR products of heterozygous mutation were further cloned into T-vectors and confirmed by sequencing. Multiple alignments were performed using ClustalX to compare PAX6 protein sequences among vertebrates. MicroRNA binding sites were predicted by TargetScan. RESULTS: A novel heterozygous PAX6 deletion c.1251_1353del103 (p.Pro418Serfs*87) affecting exon 14 and the 3'-untranslated-region (3'-UTR) was identified in the congenital aniridia family. The mutation was exclusively observed in all affected family members but not in any unaffected family member or unrelated control. Bioinformatics analysis showed that the deletion led to remarkable changes of the PAX6 protein, including a frameshift, changes of protein sequence, and a COOH-terminal extension. Multiple alignments showed that the affected region of PAX6 shared high sequence identity (100%) among its vertebrate orthologs. The COOH-terminal extension might also affect microRNA binding sites in the 3'-UTR as predicted by TargetScan. CONCLUSIONS: In the current study we reported a novel PAX6 deletion resulting in an abnormal PAX6 COOH-terminal extension in the Chinese family affected by aniridia. Our findings thus add to the mutation spectrum of PAX6.


Assuntos
Aniridia/genética , Povo Asiático/genética , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Proteínas de Ligação a RNA/genética , Proteínas Repressoras/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Estudos de Casos e Controles , Criança , Pré-Escolar , Éxons , Mutação da Fase de Leitura , Genes Dominantes , Heterozigoto , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Dados de Sequência Molecular , Fator de Transcrição PAX6 , Linhagem , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência
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