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1.
J Coll Physicians Surg Pak ; 34(6): 654-658, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840346

RESUMO

OBJECTIVE: To compare the efficacies of common therapeutic regimens and their combinations, used in polycystic ovarian syndrome (PCOS) to improve fertility in reproductive-age women. STUDY DESIGN: A descriptive study. Place and Duration of the Study: Department of Obstetric Gynaecologist, Medicare Cardiac and General Hospital, Karachi, Pakistan, from November 2022 to July 2023. METHODOLOGY: Out of 300 patients with the symptoms of menstrual irregularities and infertility, 152 were diagnosed as PCOS patients based on the ultrasound and hormonal assays and selected for study purpose. They were divided according to their therapeutic regimen into four treatment groups, treated by different therapeutic agents. Group A received metformin 500 mg/day (n = 38); Group B received metformin + myo-inositol 1g (n = 49); Group C received metformin + letrozole 2.5 mg (n = 36), and Group D received metformin + letrozole + myo-inositol (n = 29), orally for three months. All continuous variables, such as body mass index (BMI), FSH, LH, FT4, and FSI were analysed by applying t-test to all therapeutic groups, keeping p ≤0.05 as the level of significance. RESULTS: HCG-positive was found as 86% (n = 33) in Group A, 63% (n = 31) in Group B, 52% (n = 19) in Group C, and 27% (n = 08) in Group D. There were statistically significant (p <0.001) changes in BMI, FSH, LH, FT4, and FSI as well. Metformin alone and metformin plus myo-inositol came out to be more effective than other regimens. CONCLUSION: Metformin alone and myo-inositol plus metformin are effective therapeutic options in PCOS-induced infertility problems. KEY WORDS: Polycystic ovarian syndrome, Infertility, Metformin, Myo-inositol, Letrozole, Menstrual irregularities.


Assuntos
Quimioterapia Combinada , Infertilidade Feminina , Inositol , Letrozol , Metformina , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Feminino , Metformina/uso terapêutico , Inositol/uso terapêutico , Letrozol/uso terapêutico , Letrozol/administração & dosagem , Adulto , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/etiologia , Paquistão , Hipoglicemiantes/uso terapêutico , Adulto Jovem , Resultado do Tratamento , Índice de Massa Corporal
2.
Nat Biotechnol ; 42(3): 458-469, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37127662

RESUMO

Inefficient knock-in of transgene cargos limits the potential of cell-based medicines. In this study, we used a CRISPR nuclease that targets a site within an exon of an essential gene and designed a cargo template so that correct knock-in would retain essential gene function while also integrating the transgene(s) of interest. Cells with non-productive insertions and deletions would undergo negative selection. This technology, called SLEEK (SeLection by Essential-gene Exon Knock-in), achieved knock-in efficiencies of more than 90% in clinically relevant cell types without impacting long-term viability or expansion. SLEEK knock-in rates in T cells are more efficient than state-of-the-art TRAC knock-in with AAV6 and surpass more than 90% efficiency even with non-viral DNA cargos. As a clinical application, natural killer cells generated from induced pluripotent stem cells containing SLEEK knock-in of CD16 and mbIL-15 show substantially improved tumor killing and persistence in vivo.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Técnicas de Introdução de Genes , Transgenes/genética
3.
Semin Cell Dev Biol ; 124: 34-47, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34446356

RESUMO

T lymphocytes are an integral component of adaptive immunity with pleotropic effector functions. Impairment of T cell activity is implicated in various immune pathologies including autoimmune diseases, AIDS, carcinogenesis, and periodontitis. Evidently, T cell differentiation and function are under robust regulation by various endogenous factors that orchestrate underlying molecular pathways. MicroRNAs (miRNA) are a class of noncoding, regulatory RNAs that post-transcriptionally control multiple mRNA targets by sequence-specific interaction. In this article, we will review the recent progress in our understanding of miRNA-gene networks that are uniquely required by specific T cell effector functions and provide miRNA-mediated mechanisms that govern the fate of T cells. A subset of miRNAs may act in a synergistic or antagonistic manner to exert functional suppression of genes and regulate pathways that control T cell activation and differentiation. Significance of T cell-specific miRNAs and their dysregulation in immune-mediated diseases is discussed. Exosome-mediated horizontal transfer of miRNAs from antigen presenting cells (APCs) to T cells and from one T cell to another T cell subset and their impact on recipient cell functions is summarized.


Assuntos
MicroRNAs , Diferenciação Celular , Redes Reguladoras de Genes , Ativação Linfocitária , MicroRNAs/genética , MicroRNAs/metabolismo , Linfócitos T
4.
Cell Rep ; 36(3): 109410, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34289358

RESUMO

The dynamic evolution of chromatin state patterns during metastasis, their relationship with bona fide genetic drivers, and their therapeutic vulnerabilities are not completely understood. Combinatorial chromatin state profiling of 46 melanoma samples reveals an association of NRAS mutants with bivalent histone H3 lysine 27 trimethylation (H3K27me3) and Polycomb repressive complex 2. Reprogramming of bivalent domains during metastasis occurs on master transcription factors of a mesenchymal phenotype, including ZEB1, TWIST1, and CDH1. Resolution of bivalency using pharmacological inhibition of EZH2 decreases invasive capacity of melanoma cells and markedly reduces tumor burden in vivo, specifically in NRAS mutants. Coincident with bivalent reprogramming, the increased expression of pro-metastatic and melanocyte-specific cell-identity genes is associated with exceptionally wide H3K4me3 domains, suggesting a role for this epigenetic element. Overall, we demonstrate that reprogramming of bivalent and broad domains represents key epigenetic alterations in metastatic melanoma and that EZH2 plus MEK inhibition may provide a promising therapeutic strategy for NRAS mutant melanoma patients.


Assuntos
Cromatina/metabolismo , GTP Fosfo-Hidrolases/genética , Melanoma/genética , Proteínas de Membrana/genética , Mutação/genética , Complexo Repressor Polycomb 2/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Feminino , GTP Fosfo-Hidrolases/metabolismo , Histonas/metabolismo , Humanos , Melanócitos/metabolismo , Proteínas de Membrana/metabolismo , Mesoderma/metabolismo , Camundongos Nus , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Metástase Neoplásica , Complexo Repressor Polycomb 2/metabolismo , Transcrição Gênica , Carga Tumoral
5.
Histopathology ; 78(2): 321-326, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32735735

RESUMO

BACKGROUND AND AIMS: Complete loss of histone H3 lysine 27 trimethylation (H3K27me3) has recently emerged as a biomarker for malignant peripheral nerve sheath tumours (MPNST). Loss of H3K27me3 staining has also been reported in post-radiation MPNST; however, it has not been evaluated in a large series of radiation-associated sarcomas of different histological subtypes. The aim of this study was to assess H3K27me3 labelling by immunohistochemistry in radiation-associated sarcomas and to determine the prevalence of H3K27me3 loss in these tumours. METHODS AND RESULTS: Radiation-associated sarcomas (n = 119) from two tertiary care referral centres were evaluated for loss of H3K27me3, defined as complete loss of staining within tumour cells in the presence of a positive internal control. Twenty-three cases (19%) showed H3K27me3 loss, including nine of 10 (90%) MPNST, seven of 77 (9%) undifferentiated spindle cell/pleomorphic sarcomas, five of 25 (20%) angiosarcomas, one of five (20%) leiomyosarcomas and one of two (50%) osteosarcomas. CONCLUSIONS: Complete H3K27me3 loss was present in 19% of radiation-associated sarcomas in our series. Our findings demonstrate that loss of H3K27me3 is not specific for radiation-associated MPNST and may also occur in other histological subtypes of RAS, including radiation-associated undifferentiated spindle cell/pleomorphic sarcoma, angiosarcoma, leiomyosarcoma and osteosarcoma.


Assuntos
Histonas , Metilação , Neoplasias Induzidas por Radiação , Sarcoma , Biomarcadores Tumorais , Diagnóstico Diferencial , Feminino , Histonas/química , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/metabolismo , Neurilemoma/diagnóstico , Neurilemoma/metabolismo , Neurofibrossarcoma/diagnóstico , Neurofibrossarcoma/metabolismo , Radiação , Sarcoma/diagnóstico , Sarcoma/metabolismo , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/metabolismo
6.
Mol Cancer Res ; 18(1): 166-178, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31619507

RESUMO

Increased expression of protein arginine methyl transferase 6 (PRMT6) correlates with worse prognosis in lung cancer cases. To interrogate the in vivo functions of PRMT6 in lung cancer, we developed a tamoxifen-inducible lung-targeted PRMT6 gain-of-function mouse model, which mimics PRMT6 amplification events in human lung tumors. Lung-targeted overexpression of PRMT6 accelerated cell proliferation de novo and potentiated chemical carcinogen (urethane)-induced lung tumor growth. To explore the molecular mechanism/s by which PRMT6 promotes lung tumor growth, we used proteomics-based approaches and identified interleukin-enhancer binding protein 2 (ILF2) as a novel PRMT6-associated protein. Furthermore, by using a series of in vitro gain-of-function and loss-of-function experiments, we defined a new role for the PRMT6-ILF2 signaling axis in alternate activation of tumor-associated macrophages (TAM). Interestingly, we have also identified macrophage migration inhibitory factor, which has recently been shown to regulate alternate activation of TAMs, as an important downstream target of PRMT6-ILF2 signaling. Collectively, our findings reveal a previously unidentified noncatalytic role for PRMT6 in potentiating lung tumor progression via the alternate activation of TAMs. IMPLICATIONS: This is the first study to demonstrate an in vivo role for PRMT6 in lung tumor progression via the alternate activation of TAMs.


Assuntos
Neoplasias Pulmonares/genética , Macrófagos/metabolismo , Proteínas Nucleares/genética , Proteína-Arginina N-Metiltransferases/genética , Animais , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Camundongos , Análise de Sobrevida
7.
Sci Transl Med ; 11(499)2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270275

RESUMO

Although checkpoint immunotherapies have revolutionized the treatment of cancer, not all tumor types have seen substantial benefit. Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy in which very limited responses to immunotherapy have been observed. Extensive immunosuppressive myeloid cell infiltration in PDAC tissues has been postulated as a major mechanism of resistance to immunotherapy. Strategies concomitantly targeting monocyte or granulocyte trafficking or macrophage survival, in combination with checkpoint immunotherapies, have shown promise in preclinical studies, and these studies have transitioned into ongoing clinical trials for the treatment of pancreatic and other cancer types. However, compensatory actions by untargeted monocytes, granulocytes, and/or tissue resident macrophages may limit the therapeutic efficacy of such strategies. CD11b/CD18 is an integrin molecule that is highly expressed on the cell surface of these myeloid cell subsets and plays an important role in their trafficking and cellular functions in inflamed tissues. Here, we demonstrate that the partial activation of CD11b by a small-molecule agonist (ADH-503) leads to the repolarization of tumor-associated macrophages, reduction in the number of tumor-infiltrating immunosuppressive myeloid cells, and enhanced dendritic cell responses. These actions, in turn, improve antitumor T cell immunity and render checkpoint inhibitors effective in previously unresponsive PDAC models. These data demonstrate that molecular agonism of CD11b reprograms immunosuppressive myeloid cell responses and potentially bypasses the limitations of current clinical strategies to overcome resistance to immunotherapy.


Assuntos
Antígeno CD11b/agonistas , Imunidade Inata , Imunoterapia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Animais , Antígenos CD/metabolismo , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Granulócitos/metabolismo , Humanos , Cadeias alfa de Integrinas/metabolismo , Ativação de Macrófagos , Camundongos Endogâmicos C57BL , Células Mieloides/imunologia , Metástase Neoplásica , Análise de Sobrevida , Linfócitos T/imunologia , Resultado do Tratamento
8.
J Surg Oncol ; 120(3): 382-388, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31206726

RESUMO

BACKGROUND AND OBJECTIVES: Well-differentiated liposarcomas (WDL) are often partly composed of sclerotic tissue, however, the amount varies widely between tumors, and its prognostic significance is unknown. We hypothesized that tumors with more sclerosis would behave more aggressively. METHODS: Primary retroperitoneal WDL from 29 patients resected at our institution with follow-up were histologically evaluated by soft tissue pathologists blinded to outcome. Tumors with ≥ 10% sclerosis were designated "sclerotic" while tumors with < 10% sclerosis were designated as "minimally sclerotic". Cellular and dedifferentiated tumors were excluded. Clinical parameters and radiologic assessments on computed tomography (CT) were recorded. RESULTS: Histological evaluation identified 13 minimally sclerotic WDL and 16 sclerotic WDL. Median follow-up was 9 years (range, 3-20). Median recurrence-free survival (RFS) and median overall survival (OS) were 6.16 and 13.9 years, respectively. Compared with patients with sclerotic WDL, those with minimally sclerotic WDL had superior RFS (HR = 0.17 [95% CI, 0.06-0.53], P = .002) and OS (log-rank test, P = .002). Sclerotic WDL exhibited higher Houndsfield Units than minimally sclerotic WDL (26 vs 1, P = .040). CONCLUSIONS: Minimally sclerotic WDL were associated with more favorable outcome compared with sclerotic tumors. Assessment of sclerosis in WDL is likely a useful prognostic marker.


Assuntos
Lipossarcoma/patologia , Neoplasias Retroperitoneais/patologia , Esclerose/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/fisiologia , Procedimentos Cirúrgicos de Citorredução , Intervalo Livre de Doença , Feminino , Humanos , Lipossarcoma/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Retroperitoneais/cirurgia , Esclerose/cirurgia , Adulto Jovem
9.
Nat Commun ; 9(1): 5379, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30568188

RESUMO

Myeloid cells are recruited to damaged tissues where they can resolve infections and tumor growth or stimulate wound healing and tumor progression. Recruitment of these cells is regulated by integrins, a family of adhesion receptors that includes integrin CD11b. Here we report that, unexpectedly, integrin CD11b does not regulate myeloid cell recruitment to tumors but instead controls myeloid cell polarization and tumor growth. CD11b activation promotes pro-inflammatory macrophage polarization by stimulating expression of microRNA Let7a. In contrast, inhibition of CD11b prevents Let7a expression and induces cMyc expression, leading to immune suppressive macrophage polarization, vascular maturation, and accelerated tumor growth. Pharmacological activation of CD11b with a small molecule agonist, Leukadherin 1 (LA1), promotes pro-inflammatory macrophage polarization and suppresses tumor growth in animal models of murine and human cancer. These studies identify CD11b as negative regulator of immune suppression and a target for cancer immune therapy.


Assuntos
Benzoatos/uso terapêutico , Antígeno CD11b/metabolismo , Macrófagos/metabolismo , Melanoma Experimental/imunologia , MicroRNAs/metabolismo , Tioidantoínas/uso terapêutico , Animais , Benzoatos/farmacologia , Antígeno CD11b/agonistas , Macrófagos/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Camundongos Transgênicos , Neovascularização Patológica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Tioidantoínas/farmacologia
10.
Braz. j. microbiol ; 49(4): 942-948, Oct.-Dec. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974309

RESUMO

ABSTRACT The "Adopt a Bacterium" project is based on the use of social network as a tool in Microbiology undergraduate education, improving student learning and encouraging students to participate in collaborative learning. The approach involves active participation of both students and teachers, emphasizing knowledge exchange, based on widely used social media. Students were organized in groups and asked to adopt a specific bacterial genus and, subsequently, submit posts about "adopted genus". The formative assessment is based on posting information on Facebook®, and the summative assessment involves presentation of seminars about the adopted theme. To evaluate the project, students filled out three anonymous and voluntary surveys. Most of the students enjoyed the activities and positively evaluated the experience. A large amount of students declared a change in their attitude towards the way they processed information, especially regarding the use of scientific sources. Finally, we evaluated knowledge retention six months after the end of the course and students were able to recall relevant Microbiology concepts. Our results suggest that the "Adopt a Bacterium" project represents a useful strategy in Microbiology learning and may be applied to other academic fields.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Estudantes/psicologia , Conhecimento , Microbiologia/educação , Estudantes/estatística & dados numéricos , Universidades/estatística & dados numéricos , Inquéritos e Questionários , Mídias Sociais/instrumentação , Mídias Sociais/estatística & dados numéricos , Aprendizagem
11.
Histopathology ; 72(2): 239-247, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28796347

RESUMO

AIMS: Multiple genetic alterations, including alternative lengthening of telomeres (ALT) and NOTCH mutations, have been described in angiosarcoma. Loss of α-thalassaemia/mental retardation syndrome X-linked (ATRX) and death domain-associated protein 6 (DAXX) expression is frequently associated with the ALT phenotype. Additionally, inhibition of NOTCH signalling induces the development of malignant vascular tumours in mice, indicating a tumour suppressive role of the NOTCH pathway in the pathogenesis of angiosarcoma. The aim of this study was to evaluate the immunohistochemical expression of ATRX, DAXX and NOTCH receptors (NOTCH1 and NOTCH2) in a large cohort of angiosarcomas, and study their clinicopathological and prognostic significance. METHODS AND RESULTS: One hundred and forty cases of angiosarcoma were stained for ATRX, DAXX, NOTCH1 and NOTCH2. ATRX loss (<10% labelling) was seen in seven of 118 (6%) cases, and was more frequent in deep soft tissue tumours than in other body sites (P = 0.004). Angiosarcomas with ATRX loss were associated with worse event-free survival than angiosarcomas with retained ATRX expression (P = 0.003). DAXX was retained in all specimens examined. Decreased NOTCH1 expression (≤1+ intensity) was seen in 29 of 123 (24%) cases, and was associated with a cutaneous site of origin (P = 0.013) and advanced disease (P = 0.026). NOTCH2 expression was decreased in 16 of 103 (16%) cases, was associated with visceral tumours (P = 0.001), and correlated with worse disease-specific survival (P = 0.033). CONCLUSIONS: ATRX, NOTCH1 and NOTCH2 expression varies in angiosarcomas and shows significant correlations with site of origin and poor clinical outcome, thus highlighting the biological heterogeneity within this tumour type.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Biomarcadores Tumorais/análise , Hemangiossarcoma/patologia , Proteínas Nucleares/biossíntese , Receptores Notch/biossíntese , Proteína Nuclear Ligada ao X/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Correpressoras , Intervalo Livre de Doença , Feminino , Hemangiossarcoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Chaperonas Moleculares , Proteínas Nucleares/análise , Prognóstico , Receptores Notch/análise , Proteína Nuclear Ligada ao X/análise , Adulto Jovem
12.
J Clin Invest ; 127(4): 1271-1283, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28263189

RESUMO

Genetic variations in the ITGAM gene (encoding CD11b) strongly associate with risk for systemic lupus erythematosus (SLE). Here we have shown that 3 nonsynonymous ITGAM variants that produce defective CD11b associate with elevated levels of type I interferon (IFN-I) in lupus, suggesting a direct link between reduced CD11b activity and the chronically increased inflammatory status in patients. Treatment with the small-molecule CD11b agonist LA1 led to partial integrin activation, reduced IFN-I responses in WT but not CD11b-deficient mice, and protected lupus-prone MRL/Lpr mice from end-organ injury. CD11b activation reduced TLR-dependent proinflammatory signaling in leukocytes and suppressed IFN-I signaling via an AKT/FOXO3/IFN regulatory factor 3/7 pathway. TLR-stimulated macrophages from CD11B SNP carriers showed increased basal expression of IFN regulatory factor 7 (IRF7) and IFN-ß, as well as increased nuclear exclusion of FOXO3, which was suppressed by LA1-dependent activation of CD11b. This suggests that pharmacologic activation of CD11b could be a potential mechanism for developing SLE therapeutics.


Assuntos
Antígeno CD11b/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Macrófagos/imunologia , Receptores Toll-Like/imunologia , Animais , Antígeno CD11b/genética , Feminino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/imunologia , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/imunologia , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/imunologia , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos MRL lpr , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores Toll-Like/genética
13.
J Biol Chem ; 292(2): 732-747, 2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-27913625

RESUMO

Podocyte injury is an early event in diabetic kidney disease and is a hallmark of glomerulopathy. MicroRNA-146a (miR-146a) is highly expressed in many cell types under homeostatic conditions, and plays an important anti-inflammatory role in myeloid cells. However, its role in podocytes is unclear. Here, we show that miR-146a expression levels decrease in the glomeruli of patients with type 2 diabetes (T2D), which correlates with increased albuminuria and glomerular damage. miR-146a levels are also significantly reduced in the glomeruli of albuminuric BTBR ob/ob mice, indicating its significant role in maintaining podocyte health. miR-146a-deficient mice (miR-146a-/-) showed accelerated development of glomerulopathy and albuminuria upon streptozotocin (STZ)-induced hyperglycemia. The miR-146a targets, Notch-1 and ErbB4, were also significantly up-regulated in the glomeruli of diabetic patients and mice, suggesting induction of the downstream TGFß signaling. Treatment with a pan-ErbB kinase inhibitor erlotinib with nanomolar activity against ErbB4 significantly suppressed diabetic glomerular injury and albuminuria in both WT and miR-146a-/- animals. Treatment of podocytes in vitro with TGF-ß1 resulted in increased expression of Notch-1, ErbB4, pErbB4, and pEGFR, the heterodimerization partner of ErbB4, suggesting increased ErbB4/EGFR signaling. TGF-ß1 also increased levels of inflammatory cytokine monocyte chemoattractant protein-1 (MCP-1) and MCP-1 induced protein-1 (MCPIP1), a suppressor of miR-146a, suggesting an autocrine loop. Inhibition of ErbB4/EGFR with erlotinib co-treatment of podocytes suppressed this signaling. Our findings suggest a novel role for miR-146a in protecting against diabetic glomerulopathy and podocyte injury. They also point to ErbB4/EGFR as a novel, druggable target for therapeutic intervention, especially because several pan-ErbB inhibitors are clinically available.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , MicroRNAs/metabolismo , Podócitos/metabolismo , Receptor ErbB-4/biossíntese , Receptor Notch1/biossíntese , Regulação para Cima , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Cloridrato de Erlotinib/farmacologia , Camundongos , Camundongos Knockout , MicroRNAs/genética , Podócitos/patologia , Receptor ErbB-4/genética , Receptor Notch1/genética , Ribonucleases/genética , Ribonucleases/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
14.
J Am Soc Nephrol ; 26(11): 2741-52, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25858967

RESUMO

Podocyte injury and loss mark an early step in the pathogenesis of various glomerular diseases, making these cells excellent targets for therapeutics. However, cell-based high-throughput screening assays for the rational development of podocyte-directed therapeutics are currently lacking. Here, we describe a novel high-content screening-based phenotypic assay that analyzes thousands of podocytes per assay condition in 96-well plates to quantitatively measure dose-dependent changes in multiple cellular features. Our assay consistently produced a Z' value >0.44, making it suitable for compound screening. On screening with >2100 pharmacologically active agents, we identified 24 small molecules that protected podocytes against injury in vitro (1% hit rate). Among the identified hits, we confirmed an ß1-integrin agonist, pyrintegrin, as a podocyte-protective agent. Treatment with pyrintegrin prevented damage-induced decreases in F-actin stress fibers, focal adhesions, and active ß1-integrin levels in cultured cells. In vivo, administration of pyrintegrin protected mice from LPS-induced podocyte foot process effacement and proteinuria. Analysis of the murine glomeruli showed that LPS administration reduced the levels of active ß1 integrin in the podocytes, which was prevented by cotreatment with pyrintegrin. In rats, pyrintegrin reduced peak proteinuria caused by puromycin aminonucleoside-induced nephropathy. Our findings identify pyrintegrin as a potential therapeutic candidate and show the use of podocyte-based screening assays for identifying novel therapeutics for proteinuric kidney diseases.


Assuntos
Hidroxiquinolinas/química , Integrina beta1/metabolismo , Glomérulos Renais/metabolismo , Podócitos/citologia , Sulfonamidas/química , Actinas/metabolismo , Albuminúria/metabolismo , Animais , Movimento Celular , Células Epiteliais/efeitos dos fármacos , Adesões Focais/metabolismo , Ensaios de Triagem em Larga Escala , Nefropatias/metabolismo , Lipopolissacarídeos/química , Camundongos , Microscopia Confocal , Fenótipo , Proteinúria/patologia , Puromicina Aminonucleosídeo/química , Ratos
15.
Dev Cell ; 32(1): 82-96, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25584796

RESUMO

Blood vessel stability is essential for embryonic development; in the adult, many diseases are associated with loss of vascular integrity. The ETS transcription factor ERG drives expression of VE-cadherin and controls junctional integrity. We show that constitutive endothelial deletion of ERG (Erg(cEC-KO)) in mice causes embryonic lethality with vascular defects. Inducible endothelial deletion of ERG (Erg(iEC-KO)) results in defective physiological and pathological angiogenesis in the postnatal retina and tumors, with decreased vascular stability. ERG controls the Wnt/ß-catenin pathway by promoting ß-catenin stability, through signals mediated by VE-cadherin and the Wnt receptor Frizzled-4. Wnt signaling is decreased in ERG-deficient endothelial cells; activation of Wnt signaling with lithium chloride, which stabilizes ß-catenin levels, corrects vascular defects in Erg(cEC-KO) embryos. Finally, overexpression of ERG in vivo reduces permeability and increases stability of VEGF-induced blood vessels. These data demonstrate that ERG is an essential regulator of angiogenesis and vascular stability through Wnt signaling.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Neovascularização Fisiológica , Proteínas Oncogênicas/fisiologia , Fatores de Transcrição/fisiologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Células Cultivadas , Imunoprecipitação da Cromatina , Feminino , Receptores Frizzled/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Integrases/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Camundongos , Camundongos Transgênicos , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Regulador Transcricional ERG , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Wnt/genética , beta Catenina/genética
16.
J Immunol ; 190(4): 1540-50, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23319737

RESUMO

TNF superfamily member 15 (TL1A) is the ligand for TNFR superfamily (TNFRSF)25. We previously reported that TNFRSF25 stimulation with an agonist Ab, 4C12, expands pre-existing CD4(+)Foxp3(+) regulatory T cells (Tregs) in vivo. To determine how the physiological ligand differs from the Ab, we generated a soluble mouse TL1A-Ig fusion protein that forms a dimer of TL1A trimers in solution with an apparent molecular mass of 516 kDa. In vitro, TL1A-Ig mediated rapid proliferation of Foxp3(+) Tregs and a population of CD4(+)Foxp3(-) conventional T cells. TL1A-Ig also blocked de novo biogenesis of inducible Tregs and it attenuated the suppressive function of Tregs. TNFRSF25 stimulation by TL1A-Ig in vivo induced expansion of Tregs such that they increased to 30-35% of all CD4(+) T cells in the peripheral blood within 5 d of treatment. Treg proliferation in vivo was dependent on TCR engagement with MHC class II. Elevated Treg levels can be maintained for at least 20 d with daily injections of TL1A-Ig. TL1A-Ig-expanded Tregs expressed high levels of activation/memory markers KLRG1 and CD103 and were highly suppressive ex vivo. TL1A-Ig-mediated Treg expansion in vivo was protective against allergic lung inflammation, a mouse model for asthma, by reversing the ratio of conventional T cells to Tregs in the lung and blocking eosinophil exudation into the bronchoalveolar fluid. Thus, TL1A-Ig fusion proteins are highly active and tightly controllable agents to stimulate Treg proliferation in vivo, and they are uniquely able to maintain high levels of expanded Tregs by repeated administration.


Assuntos
Proteínas Recombinantes de Fusão/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/isolamento & purificação , Animais , Células CHO , Linhagem Celular Tumoral , Clonagem Molecular , Cricetinae , Citometria de Fluxo , Genes Reporter , Cadeias Pesadas de Imunoglobulinas/biossíntese , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/genética , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Insercional , Células NIH 3T3 , Plasmídeos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Hipersensibilidade Respiratória/genética , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/metabolismo , Transfecção , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/fisiologia
17.
J Biol Chem ; 287(15): 12331-42, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22337883

RESUMO

The interaction of transcription factors with specific DNA sequences is critical for activation of gene expression programs. In endothelial cells (EC), the transcription factor NF-κB is important in the switch from quiescence to activation, and is tightly controlled to avoid excessive inflammation and organ damage. Here we describe a novel mechanism that controls the activation of NF-κB in EC. The transcription factor Erg, the most highly expressed ETS member in resting EC, controls quiescence by repressing proinflammatory gene expression. Focusing on intercellular adhesion molecule 1(ICAM)-1 as a model, we identify two ETS binding sites (EBS -118 and -181) within the ICAM-1 promoter required for Erg-mediated repression. We show that Erg binds to both EBS -118 and EBS -181, the latter located within the NF-κB binding site. Interestingly, inhibition of Erg expression in quiescent EC results in increased NF-κB-dependent ICAM-1 expression, indicating that Erg represses basal NF-κB activity. Erg prevents NF-κB p65 from binding to the ICAM-1 promoter, suggesting a direct mechanism of interference. Gene set enrichment analysis of transcriptome profiles of Erg and NF-κB-dependent genes, together with chromatin immunoprecipitation (ChIP) studies, reveals that this mechanism is common to other proinflammatory genes, including cIAP-2 and IL-8. These results identify a role for Erg as a gatekeeper controlling vascular inflammation, thus providing an important barrier to protect against inappropriate endothelial activation.


Assuntos
Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/fisiologia , Transativadores/fisiologia , Fator de Transcrição RelA/metabolismo , Sítios de Ligação , Ligação Competitiva , Células Cultivadas , DNA/química , Ensaio de Desvio de Mobilidade Eletroforética , Perfilação da Expressão Gênica , Genes Reporter , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Luciferases de Renilla/biossíntese , Luciferases de Renilla/genética , Regiões Promotoras Genéticas , Ligação Proteica , Fase de Repouso do Ciclo Celular , Transativadores/química , Transativadores/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Gênica , Regulador Transcricional ERG
18.
J Coll Physicians Surg Pak ; 21(7): 403-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21777527

RESUMO

OBJECTIVE: To determine the common mutation of low density lipoprotein receptor in hypercholesterolemia patients requiring screening for heterozygous familial hypercholesterolemia (HeFH) in Karachi. STUDY DESIGN: Case-series. PLACE AND DURATION OF STUDY: Dr. Ziauddin Hospital Laboratory and Dr. Rubina Ghani's Pathological and Molecular Laboratories, Karachi, for the PCR bench work from June 2008 to October 2009. METHODOLOGY: All the patients selected for this study were from Dr. Ziauddin Hospital and National Institute of Cardiovascular Diseases. All the patients having high total cholesterol and LDL-cholesterol were included in this study with premature coronary artery diseases or a family history of hypercholesterolemia. Exclusion criteria included Diabetes mellitus, hypertension, renal disease, hypothyroidism and steroid therapy. After lipid profile with overnight fasting, DNA was extracted from whole blood collected in EDTA (ethylenediamine tetra acetic acid) tube and multiplex PCR (polymerase chain reaction) using forward and reverse primers of exons 3, 4, 9 and 14 of base pairs 162, 431, 550 and 496 respectively. RESULTS: Out of total of 120 hypercholesterolemia cases, 42 patients were classical cases of HeFH (heterozygous familial hypercholesterolemia) with xanthomas, xanthelasmas and LDL-C > 160 mg/dl. The total cholesterol (260± 57 mg/dL) and LDL-C (192 ± 39 mg/dL ) of cases was significantly high as compared to, controls having total cholesterol (184 ± 27 mg/dL) and LDL-C (105 ± 22 mg/dL), p > 0.001. Two novel point mutations were noted in exon 3 and exon 4. The other 78 cases were probable with raised LDL-C (low density lipoprotein cholesterol) and family history of premature coronary heart diseases. CONCLUSION: The frequency of HeFH was 35% classical and 65% probable cases out of total 120 hypercholesterolemia patients from two tertiary care hospitals in Karachi. The point mutation on exon 3 and exon 4 of LDLR gene was the most common. PCR is useful for the detection of large re-arrangements in the LDL-receptor gene and is a rapid and reliable method for diagnosis of familial hypercholesterolemia.


Assuntos
DNA/genética , Hiperlipoproteinemia Tipo II/genética , Mutação Puntual , Receptores de LDL/genética , Idoso , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Receptores de LDL/sangue
19.
J Coll Physicians Surg Pak ; 21(1): 30-3, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21276382

RESUMO

OBJECTIVE: To determine the variations in carotid intima-media thickness (CIMT) in familial hypercholesterolemia (FH) patients and its use as predictive marker for premature cardiovascular diseases. STUDY DESIGN: Comparative study. PLACE AND DURATION OF STUDY: National Institute of Cardiovascular Diseases and Dr. Ziauddin Hospital, Karachi, from June 2008 to October 2009. METHODOLOGY: Familial hypercholesterolemia was clinically diagnosed by premature coronary diseases, xanthomas, arcus cornealis and family history of premature coronary heart diseases. Controls were age matched normal individuals without hypercholesterolemia. Their lipid profile was tested after overnight fasting. CIMT was measured in mm using B-mode ultrasonography using linear probe. Student t-test was applied to compare mean CIMT of cases and the control. The mean CIMT values of the FH cases were correlated with LDL using Pearson's correlation test. RESULTS: Forty cases with hypercholesterolemia gave consent to participate in the study. These patients had total cholesterol ≥200 mg/dL and LDL ≥160 mg/dL as compared to twenty controls of similar age with total cholesterol ≤200 mg/dL and LDL ≤130 mg/dL. Mean CIMT for the cases was 0.77 ± 0.18 mm while mean CIMT for control was 0.59 ± 0.08 mm. The mean CIMT for the cases ranged from 0.7-1.83 mm and 0.48-0.73 mm for controls. Among the FH cases, 25% (n=11) had arterial plaques. Mean CIMT was significantly correlated to LDL-cholesterol (r = 0.725**, p < 0.001). CONCLUSION: In this study, CIMT was found to be significantly increased in familial hypercholesterolemia and it correlated with raised LDL-cholesterol. Both are predictive of premature cardiovascular diseases.


Assuntos
Artérias Carótidas/patologia , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/patologia , Adulto , Idoso , LDL-Colesterol/sangue , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Túnica Íntima/patologia , Túnica Média/patologia
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