RESUMO
Chromodomain-helicase-DNA-binding protein 1 (CHD1) deletion is among the most common mutations in prostate cancer (PCa), but its role remains unclear. In this study, RNA sequencing was conducted in PCa cells after clustered regularly interspaced palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-based CHD1 knockout. Gene set enrichment analysis (GSEA) indicated upregulation of hypoxia-related pathways. A subsequent study confirmed that CHD1 deletion significantly upregulated hypoxia-inducible factor 1α (HIF1α) expression. Mechanistic investigation revealed that CHD1 deletion upregulated HIF1α by transcriptionally downregulating prolyl hydroxylase domain protein 2 (PHD2), a prolyl hydroxylase catalyzing the hydroxylation of HIF1α and thus promoting its degradation by the E3 ligase von Hippel-Lindau tumor suppressor (VHL). Functional analysis showed that CHD1 deletion promoted angiogenesis and glycolysis, possibly through HIF1α target genes. Taken together, these findings indicate that CHD1 deletion enhances HIF1α expression through PHD2 downregulation and therefore promotes angiogenesis and metabolic reprogramming in PCa.
Assuntos
Masculino , Humanos , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Proteínas de Ligação a DNA/metabolismo , Prolil Hidroxilases/metabolismo , Hipóxia , Neoplasias da Próstata/patologia , Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linhagem Celular Tumoral , DNA Helicases/metabolismoRESUMO
Objective: To explore the potential pathogenesis of clear cell renal cell carcinoma (ccRCC) based on the HIF-1α/ACLY signaling pathway, as well as to provide new ideas for the treatment of ccRCC. Methods: Seventy-eight ccRCC cases diagnosed at the First Affiliated Hospital of Soochow University, Suzhou, China were collected. The VHL mutation was examined using exon sequencing. The expression of HIF-1α/ACLY in VHL-mutated ccRCC was evaluated using immunohistochemical staining and further validated in VHL-mutated ccRCC cell lines (786-O, A498, UM-RC-2, SNU-333, and Caki-2) using Western blot. The mRNA and protein levels of ACLY were detected using real-time quantitative PCR and Western blot after overexpression or interference with HIF-1α in ccRCC cell lines. HeLa cells were treated with CoCl2 and hypoxia (1%O2) to activate HIF-1α and then subject to the detection of the ACLY mRNA and protein levels. The potential molecular mechanism of HIF-1α-induced ACLY activation was explored through JASPAR database combined with chromatin immunoprecipitation assay (ChIP) and luciferase reporter gene assay. The effect of HIF-1α/ACLY regulation axis on lipid accumulation was detected using BODIPY staining and other cell biological techniques. The expression of ACLY was compared between patients with ccRCC and those with benign lesions, and the feasibility of ACLY as a prognostic indicator for ccRCC was explored through survival analysis. Results: Exon sequencing revealed that 55 (70.5%) of the 78 ccRCC patients harbored a VHL inactivation mutation, and HIF-1α expression was associated with ACLY protein levels. The protein levels of ACLY and HIF-1α in ccRCC cell lines carrying VHL mutation were also correlated to various degrees. Overexpression of HIF-1α in A498 cells increased the mRNA and protein levels of ACLY, and knockdown of HIF-1α in Caki-2 cells inhibited the mRNA and protein levels of ACLY (P<0.001 for all). CoCl2 and hypoxia treatment significantly increased the mRNA and protein levels of ACLY by activating HIF-1α (P<0.001 for all). The quantification of transcriptional activity of luciferase reporter gene and ChIP-qPCR results suggested that HIF-1α could directly bind to ACLY promoter region to transcriptionally activate ACLY expression and increase ACLY protein level (P<0.001 for all). The results of BODIPY staining suggested that the content of free fatty acids in cell lines was associated with the levels of HIF-1α and ACLY. The depletion of HIF-1α could effectively reduce the accumulation of lipid in cells, while the overexpression of ACLY could reverse this process. At the same time, cell function experiments showed that the proliferation rate of ccRCC cells with HIF-1α knockdown was significantly decreased, and overexpression of ACLY could restore proliferation of these tumor cells (P<0.001). Survival analysis further showed that compared with the ccRCC patients with low ACLY expression, the ccRCC patients with high ACLY expression had a poorer prognosis and a shorter median survival (P<0.001). Conclusions: VHL mutation-mediated HIF-1α overexpression in ccRCC promotes lipid synthesis and tumor progression by activating ACLY. Targeting the HIF-1α/ACLY signaling axis may provide a theoretical basis for the clinical diagnosis and treatment of ccRCC.
Assuntos
Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Células HeLa , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Mutação , Transdução de Sinais , Luciferases/uso terapêutico , Hipóxia/genética , RNA Mensageiro , Lipídeos/uso terapêutico , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão GênicaRESUMO
O carcinoma renal de células claras (CRCC) é o tipo de neoplasia renal com maior incidência, cerca de 80%. A maioria dos casos são curados após cirurgia, porém, cerca de um terço dos pacientes apresentam recidiva da doença com metástase à distância. O tratamento para este tumor evoluiu muito nas últimas duas décadas, entretanto, pacientes metastáticos ainda apresentam baixas taxas de resposta aos tratamentos devido a resistência adquirida pelo tumor para escapar da terapia alvo. Identificar os mecanismos moleculares associados à carcinogênese do CRCC é essencial para entender as características tumorais que estão associadas a progressão da doença e resistência aos tratamentos. Entre as alterações mais frequentes no CRCC está a perda do gene VHL, um supressor tumoral e principal regulador da resposta à hipóxia. VHL tem dois principais alvos, o fator induzido por hipóxia 1α (HIF-1α) e o fator induzido por hipóxia α (HIF-2α). Em normóxia, VHL é responsável pela degradação das subunidades de HIF. Em hipóxia, VHL deixa de reconhecer e marcar HIF-1α e HIF-2α para degradação e, uma vez estabilizadas, ativam vias de sinalização associadas a sobrevivência celular. As informações sobre alterações encontradas em tumores normalmente são estudadas a partir do sequenciamento da população total de mRNAs, oferecendo uma visão do transcriptoma. Nossa abordagem metodológica coleta e analisa apenas a população de mRNAs ativamente traduzidos, oferecendo uma visão mais próxima da expressão proteica final. A via de mTOR regula o início da tradução de mRNAs e está frequentemente mutada em CRCC. A hipóxia afeta a expressão de genes tanto via transcrição quanto via tradução. Alterações no controle traducional em CRCC afetam a expressão gênica contribuindo para a formação do tumor e progressão da doença. Assim, nosso objetivo principal foi identificar o perfil de genes diferencialmente traduzidos dependendo do status de VHL e da via de mTOR. Para isso utilizamos um modelo celular de CRCC deficiente em VHL e sua contraparte onde VHL foi restituído. Realizamos o perfil polissomal em modelos celulares de CRCC para separar e coletar a população de mRNAs ativamente traduzidos que foram posteriormente sequenciados. Nossos dados mostraram perfis distintos de tradução entre as células VHL- deficientes e VHL-proficientes. Além disso, após a inibição de mTOR, ambas as células também apresentaram respostas diferentes ao tratamento. Além disso, observamos alterações na resposta imune e aumento do ciclo celular na ausência de VHL, que podem contribuir para a progressão tumoral. Em modelo com tecido tumoral congelado, nossos resultados parciais indicam que alterações na tradução global podem interferir principalmente no estadiamento clínico de pacientes com CRCC. Por fim, também analisamos a expressão de HIF-2α, um dos alvos de VHL, em tecidos de pacientes com CRCC. Nossos resultados mostram que HIF-2α pode ser utilizado na estratificação de pacientes com maior risco de recidiva, dependendo do estadiamento clínico.
Clear cell renal cell carcinoma (ccRCC) is the most common type of renal neoplasia with 80% of incidence. Most cases are cured after surgery, however, one third of all patients will have disease recurrence with distant metastasis. ccRCC treatment had evolved in the past two decades, however, metastatic patients still have low response rates due to tumor resistance. The identification of molecular mechanisms associated with ccRCC carcinogenesis is essential to understand the characteristics associated with disease progression and treatment resistance. The most frequent alteration in ccRCC is the loss of VHL gene, a tumor suppressor and the main regulator in response to hypoxia. VHL has two main target, hypoxia-induced factor 1 α (HIF-1 α) and hypoxia-induced factor α (HIF-2 α). In normoxic conditions, VHL can lead HIF subunits to degradation. In hypoxia, HIF-1α and HIF-2α stabilize and activate cell survival associated signaling pathways. Studies about tumor alterations usually provides a view of the transcriptome. Our approach is based on the actively translated mRNAs collection and analysis, which provides a closer view from protein expression. mTOR pathway regulates translation initiation and is frequently mutated in ccRCC. Hypoxia affects gene expression in both transcriptional and translational regulation. Alteration in translational control in ccRCC affect gene expression which contributes to tumor progression. Our main objective was to identify the differentially translated gene profile depending on VHL status and mTOR pathway activation. To assess this, we used a VHL-deficient and a VHL-proficient ccRCC cell line. We used the polysome profiling technique to separate and collect the population of mRNAs actively translated that were subsequently sequenced. Our data showed distinct translation profiles between VHL-deficient and VHL-proficient cells. In addition, after mTOR inhibition, both cells showed different responses to treatment. We observed changes in immune response and increased cell cycle pathways in VHL deficient cells, which may contribute to tumor progression. In tumor tissue, our polysome profiling analysis indicate that changes in global translation may interfere in clinical staging of ccRCC patients. Finally, we analyzed the expression of HIF-2α, a VHL target, in ccRCC patient's tissues. Our results showed that HIF-2α can distinct patients at higher recurrence risk depending on clinical staging.
Assuntos
Humanos , RNA Mensageiro/genética , Carcinoma de Células Renais/genética , Perfilação da Expressão Gênica , Proteína Supressora de Tumor Von Hippel-Lindau , Neoplasias Renais/genética , Transdução de Sinais , Regulação Neoplásica da Expressão GênicaRESUMO
OBJECTIVE@#To explore the mechanism by which ginsenoside 20(S)-Rg3 upregulates the expression of tumor suppressor von Hippel-Lindau (VHL) gene in ovarian cancer cells.@*METHODS@#Ovarian cancer cell line SKOV3 treated with 20(S)-Rg3 were examined for mRNA and protein levels of VHL, DNMT1, DNMT3A and DNMT3B by real-time PCR and Western blotting, respectively. The changes in VHL mRNA expression in SKOV3 cells in response to treatment with 5-Aza-CdR, a DNA methyltransferase inhibitor, were detected using real-time PCR. VHL gene promoter methylation was examined with methylation-specific PCR and VHL expression levels were determined with real-time PCR and Western blotting in non-treated or 20(S)-Rg3-treated SKOV3 cells and in 20(S)-Rg3-treated DNMT3A-overexpressing SKOV3 cells. VHL and DNMT3A protein levels were detected by immunohistochemistry in subcutaneous SKOV3 cell xenografts in nude mice.@*RESULTS@#Treatment of SKOV3 cells with 20(S)-Rg3 significantly upregulated VHL and downregulated DNMT3A expressions at both the mRNA and protein levels (@*CONCLUSIONS@#Ginsenoside 20(S)-Rg3 upregulates VHL expression in ovarian cancer cells by suppressing DNMT3A-mediated DNA methylation.
Assuntos
Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Metilação de DNA , Expressão Gênica , Ginsenosídeos/farmacologia , Camundongos Nus , Neoplasias Ovarianas/genética , Regiões Promotoras Genéticas , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
OBJECTIVE@#To detect VHL gene mutation in a pedigree affected with von Hippel-Lindau syndrome (VHL).@*METHODS@#Clinical data of the pedigree was reviewed. Patients were subjected to Sanger sequencing to detect mutation of the VHL gene. Structure of pVHL was predicted by 3D modeling using the swiss-model.@*RESULTS@#A novel c.426delT(p.V142fs) [NM_000551] mutation was found in exon 2 of the VHL gene. 3D modeling suggested that the alpha-structure of pVHL is completely absent.@*CONCLUSION@#The novel c.426delT(p.V142fs) mutation probably underlies the VHL in this pedigree.
Assuntos
Humanos , Análise Mutacional de DNA , Éxons , Mutação , Linhagem , Proteína Supressora de Tumor Von Hippel-Lindau , Genética , Doença de von Hippel-Lindau , GenéticaRESUMO
OBJECTIVE@#To analyze the germline variations of genes RET, VHL, SDHD and SDHB in patients with pheochromocytoma and/or paraganglioma and to evaluate variations of these genes in Chinese patients.@*METHODS@#Patients who were treated in Peking University First Hospital from September 2012 to March 2014 and diagnosed with pheochromocytoma and/or paraganglioma by pathologists were included in this study. Twelve patients were included in total, of whom 11 had pheochromocytoma, and 1 had paraganglioma. Deoxyribonucleic acid (DNA) was extracted from the leukocytes of peripheral blood of the patients. The exons 10, 11, 13-16 of the RET gene, and all exons of VHL, SDHB and SDHD genes and their nearby introns (±20 bp) were amplified with polymerase chain reactions, and the products were sent to a biotechnology company for sequencing. The sequencing results were compared with wildtype sequences of these genes to identify variations. One of the patients was diagnosed with multiple endocrine neoplasia type 2A. A family analysis was performed in his kindred, and his family members received genetic tests for the related variations.@*RESULTS@#Three patients were found to have germline gene variations. A c.136C>T (p.R46X) variation of the SDHB gene was found in a patient with malignant pheochromocytoma. A c.1901G>A (C634Y) variation, as well as c.2071G>A (p.G691S) and c.2712C>G (p.S904S) variations of the RET gene were found in a patient with multiple endocrine neoplasia type 2A. After a family analysis, five family members of this patient were found to have the same variations. c.2071G>A (p.G691S) and c.2712C>G (p.S904S) variations of the RET gene were also found in a clinical sporadic patient without evidence of malignancy. A patient with congenital single ventricle malformation and pheochromocytoma was included in this study, and no variation with clinical significance was found in the four genes of this patient.@*CONCLUSION@#25% (3/12) patients with pheochromocytoma or paraganglioma were found to have missense or nonsense germline gene variations in this study, including the c.136C>T (p.R46X) variation of the SDHB gene, the c.1901G>A (C634Y) variation of the RET gene, and c.2071G>A (p.G691S) and c.2712C>G (p.S904S) variations of the RET gene. The former two variations have already been confirmed to be pathogenic. The existence of these variations in Chinese patients with pheochromocytoma and/or paraganglioma was validated in this study, which supports the conclusion that genetic testing is necessary to be generally performed in patients with pheochromocytoma and/or paraganglioma.
Assuntos
Humanos , Neoplasias das Glândulas Suprarrenais/genética , Testes Genéticos , Mutação em Linhagem Germinativa , Paraganglioma/genética , Feocromocitoma/genética , Proteínas Proto-Oncogênicas c-ret/genética , Succinato Desidrogenase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
LncRNA H19 encoded by the H19 imprinting gene plays an important regulatory role in the cell. Recently study has found that in hypoxic cells, the expression of H19 gene changes, and the transcription factors and protein involved in the expression change accordingly. Through the involvement of specific protein 1 (SP1), hypoxia-inducible factor-1α (HIF-1α) binds directly to the H19 promoter and induces the up-regulation of H19 expression under hypoxic conditions. The tumor suppressor protein p53 may also mediate the expression of the H19 gene, in part by interfering with HIF-la activity under hypoxia stress. The miR675-5p encoded by exon 1 of H19 promotes hypoxia response by driving the nuclear accumulation of HIF-1α and reducing the expression of VHL gene, which is a physiological HIF-1α inhibitor. In addition, under the condition of hypoxia, the expression of transporter on cell membrane changes, and the transition of the intracellular glucose metabolism pathway from aerobic oxidation to anaerobic glycolysis is also involved in the involvement of H19. Therefore, H19 may be a key gene that maintains intracellular balance under hypoxic conditions and drives adaptive cell survival under conditions of hypoxia stress.
Assuntos
Humanos , Hipóxia Celular , Genética , Genes Supressores de Tumor , Fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Genética , RNA Longo não Codificante , Regulação para Cima , Fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau , GenéticaRESUMO
The incidence of renal cell carcinoma (RCC) is increasing. Radical cure by surgery can only be achieved in patients with early stage tumors. How to precisely use antineoplastic agents after surgery is an important problem to be solved. Most metastatic RCCs are pathologically identified as clear cell RCC (ccRCC), thus to develop agents targeting ccRCC is critical. Most clinically available targeted therapies are based on targeting some spots in specific pathways; or based on targeting new anti-tumor mechanisms, such as programmed death-1(PD-1), antibody-drug conjugates (ADC) and stem cells. There is still no targeted therapy having definite effect to most RCC patients. Only von Hippel-Lindau (VHL) pathway so far has been confirmed to be related to ccRCC development and progression; the inactivation of VHL gene causes many significant downstream gene changes. The key proteins involved in VHL pathway may be potential therapeutic targets for ccRCC. In this article, we review the current progress of targeted therapy for RCC, focus on the molecular characteristics of ccRCC, its relation to VHL pathway, the potential therapeutic targets and future clinical application for metastatic ccRCC.
Assuntos
Humanos , Antineoplásicos , Usos Terapêuticos , Carcinoma de Células Renais , Tratamento Farmacológico , Neoplasias Renais , Tratamento Farmacológico , Terapia de Alvo Molecular , Metástase Neoplásica , Proteína Supressora de Tumor Von Hippel-Lindau , MetabolismoRESUMO
<p><b>BACKGROUND</b>Von Hippel-Lindau (VHL) disease is a hereditary tumor disorder caused by mutations or deletions of the VHL gene. Few studies have documented the clinical phenotype and genetic basis of the occurrence of VHL disease in China. This study armed to present clinical and genetic analyses of VHL within a five-generation VHL family from Northwestern China, and summarize the VHL mutations and clinical characteristics of Chinese families with VHL according to previous studies.</p><p><b>METHODS</b>An epidemiological investigation of family members was done to collect the general information. A retrospective study of clinical VHL cases was launched to collect the relative clinical data. Genetic linkage and haplotype analysis were used to make sure the linkage of VHL to disease in this family. The VHL gene screening was performed by directly analyzing DNA sequence output. At last, we summarized the VHL gene mutation in China by the literature review.</p><p><b>RESULTS</b>A five-generation North-western Chinese family afflicted with VHL disease was traced in this research. The family consisted of 38 living family members, of whom nine were affected. The individuals afflicted with VHL exhibited multi-organ tumors that included pheochromocytomas (8), central nervous system hemangioblastomas (3), pancreatic endocrine tumors (2), pancreatic cysts (3), renal cysts (4), and paragangliomas (2). A linkage analysis resulted in a high maximal LOD score of 8.26 (theta = 0.0) for the marker D3S1263, which is in the same chromosome region as VHL. Sequence analysis resulted in the identification of a functional C>T transition mutation (c. 499 C>T, p.R167W) located in exon 3 of the 167 th codon of VHL. All affected individuals shared this mutation, whereas the unaffected family members and an additional 100 unrelated healthy individuals did not. To date, 49 mutations have been associated with this disease in Chinese populations. The most frequent VHL mutations in China are p.S65 W, p.N78 S, p.R161Q and p.R167 W.</p><p><b>CONCLUSIONS</b>The results supported the notion that the genomic sequence that corresponds to the 167 th residue of VHL is a mutational hotspot. Further research is needed to clarify the molecular role of VHL in the development of organ-specific tumors.</p>
Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Povo Asiático , China , Haplótipos , Genética , Mutação , Linhagem , Estudos Retrospectivos , Proteína Supressora de Tumor Von Hippel-Lindau , Genética , Doença de von Hippel-Lindau , Diagnóstico , GenéticaRESUMO
<p><b>BACKGROUND</b>Vascular endothelial growth factor-targeted agents are standard treatments in advanced clear-cell renal cell carcinoma (ccRCC), but biomarkers of activity are lacking. The aim of this study was to investigate the association of Von Hippel-Lindau (VHL) gene status, vascular endothelial growth factor receptor (VEGFR) or stem cell factor receptor (KIT) expression, and their relationships with characteristics and clinical outcome of advanced ccRCC.</p><p><b>METHODS</b>A total of 59 patients who received targeted treatment with sunitinib or pazopanib were evaluated for determination at Cancer Hospital and Institute, Chinese Academy of Medical Sciences between January 2010 and November 2012. Paraffin-embedded tumor samples were collected and status of the VHL gene and expression of VEGFR and KIT were determined by VHL sequence analysis and immunohistochemistry. Clinical-pathological features were collected and efficacy such as response rate and Median progression-free survival (PFS) and overall survival (OS) were calculated and then compared based on expression status. The Chi-square test, the Kaplan-Meier method, and the Lon-rank test were used for statistical analyses.</p><p><b>RESULTS</b>Of 59 patients, objective responses were observed in 28 patients (47.5%). The median PFS was 13.8 months and median OS was 39.9 months. There was an improved PFS in patients with the following clinical features: Male gender, number of metastatic sites 2 or less, VEGFR-2 positive or KIT positive. Eleven patients (18.6%) had evidence of VHL mutation, with an objective response rate of 45.5%, which showed no difference with patients with no VHL mutation (47.9%). VHL mutation status did not correlate with either overall response rate (P = 0.938) or PFS (P = 0.277). The PFS was 17.6 months and 22.2 months in VEGFR-2 positive patients and KIT positive patients, respectively, which was significantly longer than that of VEGFR-2 or KIT negative patients (P = 0.026 and P = 0.043).</p><p><b>CONCLUSION</b>VHL mutation status could not predict the efficacy of sunitinib or pazopanib. Further investigation of VHL/VEGFR pathway components is needed.</p>
Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antineoplásicos , Usos Terapêuticos , Carcinoma de Células Renais , Genética , Mortalidade , Patologia , Intervalo Livre de Doença , Imuno-Histoquímica , Indóis , Usos Terapêuticos , Neoplasias Renais , Genética , Mortalidade , Patologia , Prognóstico , Pirimidinas , Usos Terapêuticos , Pirróis , Usos Terapêuticos , Sulfonamidas , Usos Terapêuticos , Fator A de Crescimento do Endotélio Vascular , Genética , Proteína Supressora de Tumor Von Hippel-Lindau , GenéticaRESUMO
Hypoxia-inducible factor-1alpha (HIF-1alpha) is a key transcriptional mediator that coordinates the expression of various genes involved in tumorigenesis in response to changes in oxygen tension. The stability of HIF-1alpha protein is determined by oxygen-dependent prolyl hydroxylation, which is required for binding of the von Hippel-Lindau protein (VHL), the recognition component of an E3 ubiquitin ligase that targets HIF-1alpha for ubiquitination and degradation. Here, we demonstrate that PLD2 protein itself interacts with HIF-1alpha, prolyl hydroxylase (PHD) and VHL to promote degradation of HIF-1alpha via the proteasomal pathway independent of lipase activity. PLD2 increases PHD2-mediated hydroxylation of HIF-1alpha by increasing the interaction of HIF-1alpha with PHD2. Moreover, PLD2 promotes VHL-dependent HIF-1alpha degradation by accelerating the association between VHL and HIF-1alpha. The interaction of the pleckstrin homology domain of PLD2 with HIF-1alpha also promoted degradation of HIF-1alpha and decreased expression of its target genes. These results indicate that PLD2 negatively regulates the stability of HIF-1alpha through the dynamic assembly of HIF-1alpha, PHD2 and VHL.
Assuntos
Humanos , Linhagem Celular , Células HEK293 , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fosfolipase D/metabolismo , Prolil Hidroxilases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Mapas de Interação de Proteínas , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismoRESUMO
<p><b>OBJECTIVE</b>To construct a lentiviral expression vector for human VHL and its shRNA vector, and study the effect of VHL on proliferation and apoptosis of renal cell carcinoma cell lines.</p><p><b>METHODS</b>Lentiviral vectors pZsGreen1-VHL and pLL3.7-shVHL were constructed and transfected into 293T cells with 3 packaging plasmids by Lipofectamine(TM) 2000 reagent. The supernatant was collected to infect A498 and Caki-1 cells, respectively. VHL mRNA and protein levels were detected by RT-PCR and Western blotting, respectively. The effect of VHL on the proliferation, cell cycle and cell apoptosis were analyzed by MTS and flow cytometry.</p><p><b>RESULTS</b>The recombinant lentiviral vectors were successfully constructed. The proliferation of A498 cells with reconstituted wild-type VHL was significantly inhibited, while the proliferation of Caki-1 cells with VHL knockdown was significantly enhanced as compared with the control cells (P<0.05). VHL induced G0/G1-S cell cycle arrest. The apoptosis rate of A498 cells with reconstituted wild-type VHL was significantly increased while that of Caki-1 cells with VHL knockdown was significantly lowered compared with the control cells (P<0.05).</p><p><b>CONCLUSION</b>VHL can inhibit the proliferation and induce apoptosis of renal cell carcinoma cells.</p>
Assuntos
Humanos , Apoptose , Carcinoma de Células Renais , Patologia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Vetores Genéticos , Lentivirus , Plasmídeos , RNA Mensageiro , RNA Interferente Pequeno , Transfecção , Proteína Supressora de Tumor Von Hippel-Lindau , GenéticaRESUMO
Different parasites that commonly occur concomitantly can influence one another, sometimes with unpredictable effects. We evaluated pathological aspects of dogs naturally co-infected with Leishmania infantum and Ehrlichia canis. The health status of the dogs was investigated based on histopathological, hematological and biochemical analyses of 21 animals infected solely with L. infantum and 22 dogs co- infected with L. infantum and E. canis. The skin of both groups showed chronic, predominantly lymphohistioplasmacytic inflammatory reaction. The plasmacytosis in the lymphoid tissues was likely related with the hypergammaglobulinemia detected in all the dogs. The disorganization of extracellular matrix found in the reticular dermis of the inguinal region and ear, characterized by the substitution of thick collagen fibers for thin fibers, was attributed to the degree of inflammatory reaction, irrespective of the presence of parasites. In addition, the histopathological analysis revealed that twice as many dogs in the co-infected group presented Leishmania amastigotes in the ear skin than those infected solely with Leishmania, increasing the possibility of becoming infected through sand fly vectors. Our findings highlight the fact that the health of dogs infected concomitantly with L. infantum and E. canis is severely compromised due to their high levels of total plasma protein, globulins, alkaline phosphatase and creatine kinase, and severe anemia.
A infecção simultânea por parasitas de diferentes espécies pode resultar em alterações imprevisíveis. O presente estudo avaliou a patologia de cães naturalmente coinfectados por Leishmania infantum e Ehrlichia canis. A saúde dos cães foi investigada pelas análises histopatológicas, hematológicas e bioquímicas de 21 cães infectados somente por L. infantum e 22 cães coinfectados por L. infantum e E. canis. Observou-se uma reação inflamatória crônica, predominantemente linfohistioplasmocítica, na pele dos dois grupos. A plasmocitose, encontrada nos tecidos linfóides, provavelmente estava relacionada com a hipergamaglobulinemia observada em todos os cães amostrados. A desorganização da matriz extracelular da derme da região inguinal e da orelha, demonstrada pela substituição das fibras de colágeno espessas por fibras finas, foi relacionada com o grau de reação inflamatória, independente da presença de parasitas. Ainda, observamos duas vezes mais animais do grupo coinfectado apresentando formas amastigotas na pele de orelha pela histopatologia comparado ao número de cães infectados apenas por Leishmania, tornando-os desta forma mais infectivos aos vetores. Nossos resultados ressaltam que a saúde de cães coinfectados estava severamente comprometida devido aos altos níveis de proteína plasmática total, globulinas, fosfatase alcalina, creatina quinase e anemia acentuada.
Assuntos
Humanos , Ciclina D1/genética , Genes Supressores de Tumor , Ligases/genética , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Doença de von Hippel-Lindau/genética , Northern Blotting , Carcinoma de Células Renais/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Oxigênio/farmacologia , Transfecção , Células Tumorais Cultivadas , Proteína Supressora de Tumor Von Hippel-LindauRESUMO
Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder and its clinical manifestation including haemangioblastomas of the central nervous system, renal cell carcinoma, haeochromocytomas, and pancreatic cyst. The deletion, mutation and promoter methylation of VHL gene can cause VHL disease. Swine is considered as an ideal model for human disease because of its physiological and anatomical similarity to human. We cloned pig VHL gene that is 2 725 bp in length. VHL highly expressed in adrenal gland, liver, pancreas, heart and testis. We designed 5 shRNAs and screened the most effective interference RNA fragment with a knockdown efficiency of 72%. Porcine embryonic fibroblasts stably transfected with pGenesil-shRNA vector were used as donor cells for nuclear transfer and there was no significant difference of embryo development compared with the control group. Moreover, VHL was efficiently knocked-down with efficiency of 71% in porcine cloned blastocyst, these results lay a solid foundation for constructing the VHL knock-down model of pig.
Assuntos
Animais , Clonagem Molecular , Modelos Animais de Doenças , Embrião de Mamíferos , Técnicas de Silenciamento de Genes , Suínos , Proteína Supressora de Tumor Von Hippel-Lindau , Genética , Doença de von Hippel-Lindau , GenéticaRESUMO
<p><b>BACKGROUND</b>Von Hippel-Lindau disease (VHL), a heritable autosomal dominant disease characterized by neoplasia in multiple organ systems, has rarely been reported in Asia. We genetically investigated a unique Chinese family with VHL disease and performed an analysis of the VHL protein stability.</p><p><b>METHODS</b>Genomic deoxyribonucleic acid (DNA) extracted from peripheral blood was amplified by polymerase chain reaction (PCR) to three exons of the VHL gene in 9 members of the Chinese family with VHL disease. PCR products were directly sequenced. We estimated the effects of VHL gene mutation on the stability of pVHL, which is indicated by the free energy difference between the wild-type and the mutant protein (ΔΔG).</p><p><b>RESULTS</b>The Chinese family was classified as VHL type 1. Three family members, including two patients and a carrier, had a T to G heterozygotic missense mutation at nucleotide 515 of the VHL gene exon 1. This missense mutation resulted in the transition from leucine to arginine in amino acid 101 of the VHL protein. There was low stability of the VHL protein (the ΔΔG was 12.71 kcal/mol) caused by this missense mutation.</p><p><b>CONCLUSIONS</b>We first reported a family with this VHL gene mutation in Asia. This missense mutation is predicted to significantly reduce the stability of the VHL protein and contribute to the development of the renal cell carcinoma (RCC) phenotype displayed by this family. The genetic characterization and protein stability analysis of families with VHL disease are important for early diagnosis and prevention of the disease being passed on to their offspring.</p>
Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China , Mutação de Sentido Incorreto , Estabilidade Proteica , Proteína Supressora de Tumor Von Hippel-Lindau , Química , Genética , Doença de von Hippel-Lindau , GenéticaRESUMO
<p><b>OBJECTIVE</b>Endolymphatic sac tumors (ELSTs) are rare in the general population with much higher prevalence in von Hippel-Lindau(VHL) disease. The purpose of this study is to present two cases of endolymphatic sac tumor with VHL disease with analysis of VHL gene and to explore their association with VHL disease using molecular analysis.</p><p><b>METHODS</b>Clinical data of these two patients from different VHL families were studied. DNAs extracted from peripheral bloods were amplified by the polymerase chain reaction using oligonucleotide primers corresponding to the VHL gene, then compared the mutations with the Human Gene Mutation Database.</p><p><b>RESULTS</b>In case 1, 6 family members were enrolled in the study. Among them, three had been identified to have a germline missense point mutation at codon 194 of the VHL gene exon 1 (p.S65W). The little sister of the patient (case 1) underwent vitrectomy for retinal hemangioblastoma 5 years ago in another hospital. The mother of the patient (case 1) was further diagnosed to have a cerebellar hemangioblastoma and renal carcinoma in the following physical examination. Case 2 with her parents were also tested. Codon 499 of the VHL gene exon 3 (p.R167W) were detected in case 2 and her mother, but the mother refused further examination.</p><p><b>CONCLUSIONS</b>The genetic diagnosis plays an important role in early detection of symptomatic patients and suspected patients. Clinical screening for members of the VHL families, and close follow-up of carriers allow an early detection of tumors and the metastasis, which is the most common cause of death of these patients.</p>
Assuntos
Adolescente , Adulto , Feminino , Humanos , Análise Mutacional de DNA , Neoplasias da Orelha , Genética , Saco Endolinfático , Proteína Supressora de Tumor Von Hippel-Lindau , Genética , Doença de von Hippel-Lindau , GenéticaRESUMO
CONTEXT: Extra-adrenal paragangliomas are rare tumors that have been reported in many locations, including the kidney, urethra, urinary bladder, prostate, spermatic cord, gallbladder, uterus and vagina. CASE REPORT: This report describes, for the first time to the best of our knowledge, a primary paraganglioma of the seminal vesicle occurring in a 61-year-old male. The patient presented persistent arterial hypertension and a previous diagnosis of chromophobe renal cell carcinoma. It was hypothesized that the seminal vesicle tumor could be a metastasis from the chromophobe renal cell carcinoma. Immunohistochemical characterization revealed expression of synaptophysin and chromogranin in tumor cell nests and peripheral S100 protein expression in sustentacular cells. Succinate dehydrogenase A and B-related (SDHA and SDHB) expression was present in both tumors. CONCLUSIONS: No genetic alterations to the VHL and SDHB genes were detected in either the tumor tissue or tissues adjacent to the tumor, which led us to rule out a hereditary syndrome that could explain the association between paraganglioma and chromophobe renal cell carcinoma in a patient with arterial hypertension.
CONTEXTO: Paragangliomas extra-adrenais são tumores raros que têm sido relatados em muitas localizações, incluindo rim, uretra, bexiga, próstata, cordão espermático, vesícula biliar, útero e vagina. RELATO DE CASO: Este relato descreve, pela primeira vez em nosso conhecimento, um paraganglioma primário da vesícula seminal ocorrendo em um paciente do sexo masculino de 61 anos de idade. O paciente apresentou hipertensão arterial persistente e um diagnóstico prévio de carcinoma de células renais cromófobo (CCRC). Foi pensado que o tumor de vesícula seminal poderia ser uma metástase do CCRC. A caracterização imunoistoquímica revelou expressão de sinaptofisina e cromogranina nos ninhos de células tumorais e expressão de proteína S100 nas células sustentaculares. Expressão de succinato de-hidrogenase A e B relacionada (SDHA e SDHB) estiveram presentes em ambos os tumores CONCLUSÕES: Nenhuma alteração genética dos genes VHL e SDHB foi detectada nos tecidos tumorais e adjacentes ao tumor, o que nos levou a afastar uma síndrome hereditária que poderia explicar a associação entre o paraganglioma e o CCRC em um paciente com hipertensão arterial.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Renais/patologia , Neoplasias dos Genitais Masculinos/patologia , Neoplasias Renais/patologia , Neoplasias Primárias Múltiplas/patologia , Paraganglioma/patologia , Glândulas Seminais/patologia , Diagnóstico Diferencial , Neoplasias dos Genitais Masculinos/genética , Hipertensão/etiologia , Neoplasias Primárias Múltiplas/genética , Paraganglioma/genética , Succinato Desidrogenase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
<p><b>BACKGROUND</b>Von Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.</p><p><b>METHODS</b>Nine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).</p><p><b>RESULTS</b>The nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.</p><p><b>CONCLUSIONS</b>Genetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.</p>
Assuntos
Humanos , Povo Asiático , Análise Mutacional de DNA , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Proteína Supressora de Tumor Von Hippel-Lindau , Genética , Doença de von Hippel-Lindau , GenéticaRESUMO
Rica em compostos bioativos, a própolis é amplamente utilizada na medicina alternativa como agente preventivo e/ou terapêutico. Neste trabalho, avaliamos o impacto de frações ricas em polifenóis de diferentes própolis no processo de angiogênese na aterosclerose. Foram utilizadas as seguintes amostras de própolis: Red (vermelho, Alagoas-Brasil), Green (verde, Minas Gerais-Brasil) e Brown (marrom, Temuco-Chile), com concentrações semelhantes de polifenóis totais (~32%), porém com diferentes perfis de compostos fenólicos. A suplementação (250 mg/Kg/dia) de camundongos knockout para o receptor de LDL (LDLr-/-) com os polifenóis demonstrou que no protocolo de lesão inicial (LI) os grupos suplementados apresentaram menor (p<0,05) área de lesão (Green, 726µm2; Red, 519µm2; Brown, 698µm2) em relação ao controle (GC, 1184µm2). Em contraste, no protocolo de lesão avançada (LA) apenas o grupo Red (1082µm2) apresentou menor (p<0,05) área de lesão em relação ao GC (1598µm2). Em ambos os protocolos (LI e LA) observou-se redução (p<0,05) na expressão de importantes genes envolvidos no processo de angiogênese (VEGF, MMP9, PDGF e PECAM). No entanto, apenas o grupo tratado com a própolis Red foi capaz de aumentar (p<0,05) a expressão de TIMP-1 no protocolo de LI. Todos os tratamentos inibiram (p<0,05), em cerca de 45%, a migração de células endoteliais (CE), bem como cerca de 55% do brotamento de tubos de anéis de aorta, em relação ao controle e ao redor de 50% da formação de novos vasos na membrana corioalantóica de embrião de galinha (CAM). Ao investigar o mecanismo de ação dos polifenóis, observamos que os polifenóis da própolis Red (PRP) mostraram-se mais eficazes em modular a expressão do Fator induzido por Hipóxia-1 alfa (HIF-1α), de modo dose/tempo dependente em células endoteliais. Adicionalmente, os polifenóis da própolis Red (PRP) reduziram a expressão de genes alvos regulados por HIF-1α como GLUT-1 e ADM, além de inibir a expressão gênica e a secreção de VEGF em...
Propolis is rich in bioactive compounds and widely used in alternative medicine as a preventive agent and/or in therapy. We evaluate the impact of polyphenol-rich fractions of propolis from different origins and types in the angiogenesis process in atherosclerotic lesions. The following samples of propolis were used: Red (red, Alagoas, Brazil), Green (green, Minas Gerais, Brazil) and Brown (brown, Temuco, Chile), with similar concentrations of total polyphenols (~ 32%) but with different profiles of phenolic compounds. Supplementation (250 mg / kg / day) of knockout mice for the LDL receptor (LDLr-/ -) with polyphenols showed that in the initial lesion (LI) protocol supplemented groups had lower (p<0.05) lesion area (Green, 726µm2; Red, 519µm2; Brown 698µm2) compared to control (GC, 1184µm2). In contrast, in the advanced lesions (LA) protocol only the Red group (1082µm2) had smaller lesion area (p<0.05) compared to GC (1598µm2). In both protocols (LI and LA) a reduction (p<0.05 of important genes expression involved in angiogenesis (VEGF, MMP9, PDGF and PECAM) was observed. However, only the group treated with Red propolis was able to increase (p <0.05) the expression of TIMP-1 in the LI protocol. The treatments with all types of propolis inhibited (p<0.05), about 45% the migration of endothelial cells (EC), approximately 55% of tubes formation in aortic rings and almost 50% of formation of new vessels in the chorioallantoic membrane of chick embryo (CAM) compared to the control. While investigating the mechanism of polyphenols action, it was found that polyphenols from Red propolis (PRP) were more effective in modulating the expression of hypoxia-induced factor-1 alpha (HIF-1α) in a dose/time dependent way in EC. Additionally, the polyphenols from red propolis (PRP) reduced the expression of target genes regulated by HIF-11α as GLUT-1, ADM, VEGF besides the VEGF protein secretion in the EC culture medium. In the presence of PRP, the degradation of HIF-11α...
Assuntos
Animais , Masculino , Adulto , Camundongos , Inibidores da Angiogênese , Aterosclerose , Sinergismo Farmacológico , Própole , Doenças Vasculares , Fator 1 Induzível por Hipóxia , Compostos Fenólicos , Fator A de Crescimento do Endotélio Vascular , Proteína Supressora de Tumor Von Hippel-LindauRESUMO
Von Hippel Lindau disease is a hereditary syndrome characterized by the appearance of benign and malignant tumors in different organs. Its incidence is 1 case per 36000 born alive. We report a family with the disease. The index case was a male with a bilateral pheochromocytoma and cerebelar and retinal hemagioblastomas that had a sudden death due to a cerebrovascular accident at the age of 52 years. One sibling had central nervous system and retinal hemangioblastomas and other was operated for an unilateral pheochromocytoma. Both siblings had the R167Q VHL mutation of the syndrome. Other family members did not have the mutation.