Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
2.
Neuron ; 111(12): 1933-1951.e3, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37086722

RESUMO

Cholinergic interneurons are central hubs of the striatal neuronal network, controlling information processing in a behavioral-state-dependent manner. It remains unknown, however, how such state transitions influence the integrative properties of these neurons. To address this, we made simultaneous somato-dendritic recordings from identified rodent cholinergic interneurons, revealing that action potentials are initiated at dendritic sites because of a dendritic axonal origin. Functionally, this anatomical arrangement ensured that the action potential initiation threshold was lowest at axon-bearing dendritic sites, a privilege efficacy powerfully accentuated at the hyperpolarized membrane potentials achieved in cholinergic interneurons following salient behavioral stimuli. Experimental analysis revealed the voltage-dependent attenuation of the efficacy of non-axon-bearing dendritic excitatory input was mediated by the recruitment of dendritic potassium channels, a regulatory mechanism that, in turn, was controlled by the pharmacological activation of neurokinin receptors. Together, these results indicate that the neuropeptide microenvironment dynamically controls state- and compartment-dependent dendritic information processing in striatal cholinergic interneurons.


Assuntos
Colinérgicos , Corpo Estriado , Colinérgicos/farmacologia , Potenciais da Membrana/fisiologia , Potenciais de Ação/fisiologia , Peptídeos , Interneurônios/fisiologia , Neurônios Colinérgicos/fisiologia
3.
Sci Rep ; 13(1): 2864, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36806315

RESUMO

Platelets play a crucial role in cancer and thrombosis. However, the receptor-ligand repertoire mediating prostate cancer (PCa) cell-platelet interactions and ensuing consequences have not been fully elucidated. Microvilli emanating from the plasma membrane of PCa cell lines (RC77 T/E, MDA PCa 2b) directly contacted individual platelets and platelet aggregates. PCa cell-platelet interactions were associated with calcium mobilization in platelets, and translocation of P-selectin and integrin αIIbß3 onto the platelet surface. PCa cell-platelet interactions reciprocally promoted PCa cell invasion and apoptotic resistance, and these events were insensitive to androgen receptor blockade by bicalutamide. PCa cells were exceedingly sensitive to activation by platelets in vitro, occurring at a PCa cell:platelet coculture ratio as low as 1:10 (whereas PCa patient blood contains 1:2,000,000 per ml). Conditioned medium from cocultures stimulated PCa cell invasion but not apoptotic resistance nor platelet aggregation. Candidate transmembrane signaling proteins responsible for PCa cell-platelet oncogenic events were identified by RNA-Seq and broadly divided into 4 major categories: (1) integrin-ligand, (2) EPH receptor-ephrin, (3) immune checkpoint receptor-ligand, and (4) miscellaneous receptor-ligand interactions. Based on antibody neutralization and small molecule inhibitor assays, PCa cell-stimulated calcium mobilization in platelets was found to be mediated by a fibronectin1 (FN1)-αIIbß3 signaling axis. Platelet-stimulated PCa cell invasion was facilitated by a CD55-adhesion G protein coupled receptor E5 (ADGRE5) axis, with contribution from platelet cytokines CCL3L1 and IL32. Platelet-stimulated PCa cell apoptotic resistance relied on ephrin-EPH receptor and lysophosphatidic acid (LPA)-LPA receptor (LPAR) signaling. Of participating signaling partners, FN1 and LPAR3 overexpression was observed in PCa specimens compared to normal prostate, while high expression of CCR1 (CCL3L1 receptor), EPHA1 and LPAR5 in PCa was associated with poor patient survival. These findings emphasize that non-overlapping receptor-ligand pairs participate in oncogenesis and thrombosis, highlighting the complexity of any contemplated clinical intervention strategy.


Assuntos
Cálcio , Neoplasias da Próstata , Masculino , Humanos , Ligantes , Receptor EphA1 , Integrinas
4.
Anal Chem ; 94(37): 12788-12797, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36074029

RESUMO

Parathyroid hormone-related peptide (PTHrP) is related to bone metastasis and hypercalcemia in prostate and breast cancers and should be an excellent biomarker for aggressive forms of these cancers. Current clinical detection protocols for PTHrP are immunoradiometric assay and radioimmunoassay but are not sensitive enough to detect PTHrPs at early stages. We recently evaluated a prostate cancer biomarker panel, including serum monocyte differentiation antigen (CD-14), ETS-related gene protein, pigment epithelial-derived factor, and insulin-like growth factor-1, with promise for identifying aggressive prostate cancers. This panel predicted the need for patient biopsy better than PSA alone. In the present paper, we report an ultrasensitive microfluidic assay for PTHrPs and evaluate their diagnostic value and the value of including them with our prior biomarker panel to diagnose aggressive forms of prostate cancer. The immunoarray features screen-printed carbon sensor electrodes coated with 5 nm glutathione gold nanoparticles with capture antibodies attached. PTHrPs are bound to a secondary antibody attached to a polyhorseradish peroxidase label and delivered to the sensors to provide high sensitivity when activated by H2O2 and a mediator. We obtained an unprecedented 0.3 fg mL-1 limit of detection for PTHrP bioactive moieties PTHrP 1-173 and PTHrP 1-86. We also report the first study of PTHrPs in a large serum pool to identify aggressive malignancies. In assays of 130 human patient serum samples, PTHrP levels distinguished between aggressive and indolent prostate cancers with 83-91% clinical sensitivity and 78-96% specificity. Logistic regression identified the best predictive model as a combination of PTHrP 1-86 and vascular endothelial growth factor-D. PTHrP 1-173 alone also showed a high ability to differentiate aggressive and indolent cancers.


Assuntos
Nanopartículas Metálicas , Neoplasias da Próstata , Biomarcadores Tumorais , Carbono , Glutationa , Ouro , Humanos , Peróxido de Hidrogênio , Fator de Crescimento Insulin-Like I , Masculino , Hormônio Paratireóideo , Proteína Relacionada ao Hormônio Paratireóideo , Peroxidases , Próstata/metabolismo , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , Fator D de Crescimento do Endotélio Vascular
5.
Cell Mol Gastroenterol Hepatol ; 13(5): 1510-1529, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35093590

RESUMO

BACKGROUND & AIMS: The liver has a unique capacity to regenerate after injury in a highly orchestrated and regulated manner. Here, we report that O-GlcNAcylation, an intracellular post-translational modification regulated by 2 enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), is a critical termination signal for liver regeneration following partial hepatectomy (PHX). METHODS: We studied liver regeneration after PHX on hepatocyte specific OGT and OGA knockout mice (OGT-KO and OGA-KO), which caused a significant decrease (OGT-KO) and increase (OGA-KO) in hepatic O-GlcNAcylation, respectively. RESULTS: OGA-KO mice had normal regeneration, but the OGT-KO mice exhibited substantial defects in termination of liver regeneration with increased liver injury, sustained cell proliferation resulting in significant hepatomegaly, hepatic dysplasia, and appearance of small nodules at 28 days after PHX. This was accompanied by a sustained increase in expression of cyclins along with significant induction in pro-inflammatory and pro-fibrotic gene expression in the OGT-KO livers. RNA-sequencing studies revealed inactivation of hepatocyte nuclear 4 alpha (HNF4α), the master regulator of hepatic differentiation and a known termination signal, in OGT-KO mice at 28 days after PHX, which was confirmed by both Western blot and immunohistochemistry analysis. Furthermore, a significant decrease in HNFα target genes was observed in OGT-KO mice, indicating a lack of hepatocyte differentiation following decreased hepatic O-GlcNAcylation. Immunoprecipitation experiments revealed HNF4α is O-GlcNAcylated in normal differentiated hepatocytes. CONCLUSIONS: These studies show that O-GlcNAcylation plays a critical role in the termination of liver regeneration via regulation of HNF4α in hepatocytes.


Assuntos
Hepatócitos , Regeneração Hepática , Animais , Hepatectomia , Hepatócitos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Knockout
6.
Cancer Res Commun ; 2(11): 1355-1371, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36643868

RESUMO

Prostate cell lines from diverse backgrounds are important to addressing disparities in prostate cancer (PCa) incidence and mortality rates among Black men. ACRJ-PC28 was developed from a transrectal needle biopsy and established via inactivation of the CDKN2A locus and simultaneous expression of human telomerase. Characterization assays included growth curve analysis, immunoblots, IHC, 3D cultures, immunofluorescence imaging, confocal microscopy, flow cytometry, WGS, and RNA-Seq. ACRJ-PC28 has been passaged more than 40 times in vitro over 10 months with a doubling time of 45 hours. STR profiling confirmed the novelty and human origin of the cell line. RNA-Seq confirmed the expression of prostate specific genes alpha-methylacyl-CoA racemase (AMACR) and NKX3.1 and Neuroendocrine specific markers synaptophysin (SYP) and enolase 2 (ENO2) and IHC confirmed the presence of AMACR. Immunoblots indicated the cell line is of basal-luminal type; expresses p53 and pRB and is AR negative. WGS confirmed the absence of exonic mutations and the presence of intronic variants that appear to not affect function of AR, p53, and pRB. RNA-Seq data revealed numerous TP53 and RB1 mRNA splice variants and the lack of AR mRNA expression. This is consistent with retention of p53 function in response to DNA damage and pRB function in response to contact inhibition. Soft agar anchorage-independent analysis indicated that the cells are transformed, confirmed by principal component analysis (PCA) where ACRJ-PC28 cells cluster alongside other PCa tumor tissues, yet was distinct. The novel methodology described should advance prostate cell line development, addressing the disparity in PCa among Black men.


Assuntos
Células Neuroendócrinas , Neoplasias da Próstata , Masculino , Humanos , Proteína Supressora de Tumor p53/genética , Células Neuroendócrinas/metabolismo , Neoplasias da Próstata/genética , Linhagem Celular , RNA Mensageiro , Região do Caribe
7.
J Am Soc Nephrol ; 32(11): 2834-2850, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34716244

RESUMO

BACKGROUND: CKD, characterized by retained uremic solutes, is a strong and independent risk factor for thrombosis after vascular procedures . Urem ic solutes such as indoxyl sulfate (IS) and kynurenine (Kyn) mediate prothrombotic effect through tissue factor (TF). IS and Kyn biogenesis depends on multiple enzymes, with therapeutic implications unexplored. We examined the role of indoleamine 2,3-dioxygenase-1 (IDO-1), a rate-limiting enzyme of kynurenine biogenesis, in CKD-associated thrombosis after vascular injury. METHODS: IDO-1 expression in mice and human vessels was examined. IDO-1-/- mice, IDO-1 inhibitors, an adenine-induced CKD, and carotid artery injury models were used. RESULTS: Both global IDO-1-/- CKD mice and IDO-1 inhibitor in wild-type CKD mice showed reduced blood Kyn levels, TF expression in their arteries, and thrombogenicity compared with respective controls. Several advanced IDO-1 inhibitors downregulated TF expression in primary human aortic vascular smooth muscle cells specifically in response to uremic serum. Further mechanistic probing of arteries from an IS-specific mouse model, and CKD mice, showed upregulation of IDO-1 protein, which was due to inhibition of its polyubiquitination and degradation by IS in vascular smooth muscle cells. In two cohorts of patients with advanced CKD, blood IDO-1 activity was significantly higher in sera of study participants who subsequently developed thrombosis after endovascular interventions or vascular surgery. CONCLUSION: Leveraging genetic and pharmacologic manipulation in experimental models and data from human studies implicate IS as an inducer of IDO-1 and a perpetuator of the thrombotic milieu and supports IDO-1 as an antithrombotic target in CKD.


Assuntos
Indicã/fisiologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/sangue , Cinurenina/fisiologia , Terapia de Alvo Molecular , Complicações Pós-Operatórias/enzimologia , Insuficiência Renal Crônica/enzimologia , Trombose/enzimologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Animais , Aorta , Lesões das Artérias Carótidas/complicações , Trombose das Artérias Carótidas/etiologia , Trombose das Artérias Carótidas/prevenção & controle , Meios de Cultura/farmacologia , Indução Enzimática/efeitos dos fármacos , Retroalimentação Fisiológica , Feminino , Células HEK293 , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Cinurenina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/efeitos dos fármacos , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Insuficiência Renal Crônica/tratamento farmacológico , Tromboplastina/metabolismo , Trombose/sangue , Trombose/etiologia , Trombose/prevenção & controle , Triptofano/metabolismo , Uremia/sangue
8.
Surgery ; 170(4): 1160-1167, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34016457

RESUMO

BACKGROUND: Black Americans have a higher incidence and mortality rate from colorectal cancer compared to their non-Hispanic White American counterparts. Even when controlling for sociodemographic differences between these 2 populations, Black Americans remain disproportionately affected by colorectal cancer. The purpose of our study was to determine if differences in gene expression between Black American and non-Hispanic White American colon cancer specimens could help explain differences in the incidence and mortality rate between these 2 populations. METHODS: Black Americans and non-Hispanic White Americans undergoing colon resection for stages I, II, or III colon cancer at a single institution were identified. Black American and non-Hispanic White American patients were matched for age, sex, and colon cancer stage to minimize the risk of confounding variables. Tissue samples were obtained at the time of colon resection and were analyzed using RNA sequencing to determine if there were differences in the expression of genes and biologic processes between the 2 groups. RESULTS: A total of 17 colon cancer specimens were analyzed; 8 (47.1%) patients were Black Americans. A total of 456 genes were identified as being expressed differently (ie, up or downregulated) in Black American compared to non-Hispanic White American colon cancer specimens. Moreover, 500 different genetic pathways were noted to be significantly over-represented with differentially expressed genes in our comparison of Black American and non-Hispanic White American colon cancer specimens, the majority of which plays a role in inflammation and immune cell function. CONCLUSION: Significant differences in gene expression and genetic pathways exist between Black Americans and non-Hispanic White Americans. Additional and multi-institutional and registry-based studies are needed to validate our findings and to further elucidate the contribution that these differences have to the overall incidence and mortality rate from colon cancer in these 2 patient populations.


Assuntos
Negro ou Afro-Americano/genética , Neoplasias do Colo/genética , Genômica/métodos , Disparidades em Assistência à Saúde , RNA Neoplásico/genética , Centros de Atenção Terciária , Idoso , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/etnologia , Colonoscopia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Retrospectivos , Análise de Sequência de RNA , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
9.
Anal Chem ; 93(2): 1059-1067, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33289381

RESUMO

The inability to distinguish aggressive from indolent prostate cancer is a longstanding clinical problem. Prostate specific antigen (PSA) tests and digital rectal exams cannot differentiate these forms. Because only ∼10% of diagnosed prostate cancer cases are aggressive, existing practice often results in overtreatment including unnecessary surgeries that degrade patients' quality of life. Here, we describe a fast microfluidic immunoarray optimized to determine 8-proteins simultaneously in 5 µL of blood serum for prostate cancer diagnostics. Using polymeric horseradish peroxidase (poly-HRP, 400 HRPs) labels to provide large signal amplification and limits of detection in the sub-fg mL-1 range, a protocol was devised for the optimization of the fast, accurate assays of 100-fold diluted serum samples. Analysis of 130 prostate cancer patient serum samples revealed that some members of the protein panel can distinguish aggressive from indolent cancers. Logistic regression was used to identify a subset of the panel, combining biomarker proteins ETS-related gene protein (ERG), insulin-like growth factor-1 (IGF-1), pigment epithelial-derived factor (PEDF), and serum monocyte differentiation antigen (CD-14) to predict whether a given patient should be referred for biopsy, which gave a much better predictive accuracy than PSA alone. This represents the first prostate cancer blood test that can predict which patients will have a high biopsy Gleason score, a standard pathology score used to grade tumors.


Assuntos
Biomarcadores Tumorais/sangue , Imunoensaio , Técnicas Analíticas Microfluídicas , Proteínas de Neoplasias/sangue , Neoplasias da Próstata/diagnóstico , Humanos , Masculino , Neoplasias da Próstata/sangue
10.
Blood ; 134(26): 2399-2413, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31877217

RESUMO

Patients with malignancy are at 4- to 7-fold higher risk of venous thromboembolism (VTE), a potentially fatal, yet preventable complication. Although general mechanisms of thrombosis are enhanced in these patients, malignancy-specific triggers and their therapeutic implication remain poorly understood. Here we examined a colon cancer-specific VTE model and probed a set of metabolites with prothrombotic propensity in the inferior vena cava (IVC) ligation model. Athymic mice injected with human colon adenocarcinoma cells exhibited significantly higher IVC clot weights, a biological readout of venous thrombogenicity, compared with the control mice. Targeted metabolomics analysis of plasma of mice revealed an increase in the blood levels of kynurenine and indoxyl sulfate (tryptophan metabolites) in xenograft-bearing mice, which correlated positively with the increase in the IVC clot size. These metabolites are ligands of aryl hydrocarbon receptor (AHR) signaling. Accordingly, plasma from the xenograft-bearing mice activated the AHR pathway and augmented tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1) levels in venous endothelial cells in an AHR-dependent manner. Consistent with these findings, the endothelium from the IVC of xenograft-bearing animals revealed nuclear AHR and upregulated TF and PAI-1 expression, telltale signs of an activated AHR-TF/PAI-1 axis. Importantly, pharmacological inhibition of AHR activity suppressed TF and PAI-1 expression in endothelial cells of the IVC and reduced clot weights in both kynurenine-injected and xenograft-bearing mice. Together, these data show dysregulated tryptophan metabolites in a mouse cancer model, and they reveal a novel link between these metabolites and the control of the AHR-TF/PAI-1 axis and VTE in cancer.


Assuntos
Neoplasias do Colo/complicações , Modelos Animais de Doenças , Metaboloma , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Tromboplastina/metabolismo , Tromboembolia Venosa/etiologia , Animais , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Transdução de Sinais , Triptofano/metabolismo , Tromboembolia Venosa/metabolismo , Tromboembolia Venosa/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Adv Exp Med Biol ; 1164: 119-139, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576545

RESUMO

Alternative splicing, the process of removing introns and joining exons of pre-mRNA, is critical for growth, development, tissue homeostasis, and species diversity. Dysregulation of alternative splicing can initiate and drive disease. Aberrant alternative splicing has been shown to promote the "hallmarks of cancer" in both hematological and solid cancers. Of interest, recent work has focused on the role of alternative splicing in prostate cancer and prostate cancer health disparities. We will provide a review of prostate cancer health disparities involving the African American population, alternative RNA splicing, and alternative splicing in prostate cancer. Lastly, we will summarize our work on differential alternative splicing in prostate cancer disparities and its implications for disparate health outcomes and therapeutic targets.


Assuntos
Processamento Alternativo , Resistência a Medicamentos , Disparidades nos Níveis de Saúde , Neoplasias da Próstata , Negro ou Afro-Americano/estatística & dados numéricos , Processamento Alternativo/genética , Resistência a Medicamentos/genética , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/fisiopatologia
13.
Org Lett ; 21(18): 7592-7596, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31490082

RESUMO

Pentalenolactone is a microbial sesquiterpenoid with antibiotic activity. Its biosynthetic pathway was elucidated by a combination of genetic and biochemical characterizations of all genes involved. For the related neopentalenoketolactone biosynthetic gene cluster from Streptomyces avermitilis, an α-ketoglutarate-dependent mononuclear nonheme iron enzyme, PtlD, was proposed to catalyze both desaturation and olefin epoxidation reactions. Yet, these activities remained to be validated by in vitro biochemical evidence. In this report, we demonstrated that PtlD has multiple activities, including hydroxylation, desaturation, and epoxidation, and confirmed the presence of the elusive epoxide intermediate in a neopentalenoketolactone pathway.


Assuntos
Lactonas/metabolismo , Enzimas Multifuncionais/metabolismo , Sesquiterpenos/metabolismo , Lactonas/química , Conformação Molecular , Sesquiterpenos/química , Estereoisomerismo , Streptomyces/enzimologia
14.
Mol Cancer Res ; 17(10): 2115-2125, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31266816

RESUMO

Alternative splicing (AS) has been shown to participate in prostate cancer development and progression; however, a link between AS and prostate cancer health disparities has been largely unexplored. Here we report on the cloning of a novel splice variant of FGFR3 that is preferentially expressed in African American (AA) prostate cancer. This novel variant (FGFR3-S) omits exon 14, comprising 123 nucleotides that encode the activation loop in the intracellular split kinase domain. Ectopic overexpression of FGFR3-S in European American (EA) prostate cancer cell lines (PC-3 and LNCaP) led to enhanced receptor autophosphorylation and increased activation of the downstream signaling effectors AKT, STAT3, and ribosomal S6 compared with FGFR3-L (retains exon 14). The increased oncogenic signaling imparted by FGFR3-S was associated with a substantial gain in proliferative and antiapoptotic activities, as well as a modest but significant gain in cell motility. Moreover, the FGFR3-S-conferred proliferative and motility gains were highly resistant to the pan-FGFR small-molecule inhibitor dovitinib and the antiapoptotic gain was insensitive to the cytotoxic drug docetaxel, which stands in marked contrast with dovitinib- and docetaxel-sensitive FGFR3-L. In an in vivo xenograft model, mice injected with PC-3 cells overexpressing FGFR3-S exhibited significantly increased tumor growth and resistance to dovitinib treatment compared with cells overexpressing FGFR3-L. In agreement with our in vitro and in vivo findings, a high FGFR3-S/FGFR3-L expression ratio in prostate cancer specimens was associated with poor patient prognosis. IMPLICATIONS: This work identifies a novel FGFR3 splice variant and supports the hypothesis that differential AS participates in prostate cancer health disparities.


Assuntos
Negro ou Afro-Americano/genética , Docetaxel/farmacologia , Neoplasias da Próstata/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Processamento Alternativo , Animais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Células PC-3 , Fenótipo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Splicing de RNA , Coelhos , Transdução de Sinais , Análise de Sobrevida , Transfecção
15.
Anal Chem ; 91(11): 7394-7402, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31050399

RESUMO

We report herein a novel pipet-based "ELISA in a tip" as a new versatile diagnostic tool featuring better sensitivity, shorter incubation time, accessibility, and low sample and reagent volumes compared to traditional ELISA. Capture and analysis of data by a cell phone facilitates electronic delivery of results to health care providers. Pipette tips were designed and 3D printed as adapters to fit most commercial 50-200 µL pipettes. Capture antibodies (Ab1) are immobilized on the inner walls of the pipet tip, which serves as the assay compartment where samples and reagents are moved in and out by pipetting. Signals are generated using colorimetric or chemiluminescent (CL) reagents and can be quantified using a cell phone, CCD camera, or plate reader. We utilized pipet-tip ELISA to detect four cancer biomarker proteins with detection limits similar to or lower than microplate ELISAs at 25% assay cost and time. Recoveries of these proteins from spiked human serum were 85-115% or better, depending slightly on detection mode. Using CCD camera quantification of CL with femto-luminol reagent gave limits of detection (LOD) as low as 0.5 pg/mL. Patient samples (13) were assayed for 3 biomarker proteins with results well correlated to conventional ELISA and an established microfluidic electrochemical immunoassay.


Assuntos
Biomarcadores Tumorais/análise , Ensaio de Imunoadsorção Enzimática , Impressão Tridimensional , Neoplasias da Próstata/diagnóstico , Telemedicina , Anticorpos/imunologia , Biomarcadores Tumorais/imunologia , Técnicas Biossensoriais , Telefone Celular , Técnicas Eletroquímicas , Humanos , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/imunologia , Receptores de Lipopolissacarídeos/análise , Receptores de Lipopolissacarídeos/imunologia , Masculino , Técnicas Analíticas Microfluídicas , Antígeno Prostático Específico/análise , Antígeno Prostático Específico/imunologia
16.
Sci Rep ; 9(1): 6136, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992475

RESUMO

Histone deacetylases (HDACs) are involved in diverse cellular regulatory mechanisms including non-canonical functions outside the chromatin environment. Several publications have demonstrated that selective HDAC inhibitors (HDACi) can influence tumor immunogenicity and the functional activity of specific immune cells. In particular, the selective inhibition of HDAC6 has been reported to decrease tumor growth in several malignancies. However, there is still no clarity about the cellular components mediating this effect. In this study, we evaluated the HDAC6i Nexturastat A as a priming agent to facilitate the transition of the tumor microenvironment from "cold" to "hot", and potentially augment immune check-point blockade therapies. This combination modality demonstrated to significantly reduce tumor growth in syngeneic melanoma tumor models. Additionally, we observed a complete neutralization of the up-regulation of PD-L1 and other immunosuppressive pathways induced by the treatment with anti-PD-1 blockade. This combination also showed profound changes in the tumor microenvironment such as enhanced infiltration of immune cells, increased central and effector T cell memory, and a significant reduction of pro-tumorigenic M2 macrophages. The evaluation of individual components of the tumor microenvironment suggested that the in vivo anti-tumor activity of HDAC6i is mediated by its effect on tumor cells and tumor-associated macrophages, and not directly over T cells. Overall, our results indicate that selective HDAC6i could be used as immunological priming agents to sensitize immunologically "cold" tumors and subsequently improve ongoing immune check-point blockade therapies.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/uso terapêutico , Macrófagos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Anti-Inflamatórios/uso terapêutico , Antígeno B7-H1/imunologia , Desacetilase 6 de Histona/imunologia , Tolerância Imunológica/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Microambiente Tumoral/efeitos dos fármacos
17.
Cancers (Basel) ; 10(11)2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30463359

RESUMO

More than 95% of the 20,000 to 25,000 transcribed human genes undergo alternative RNA splicing, which increases the diversity of the proteome. Isoforms derived from the same gene can have distinct and, in some cases, opposing functions. Accumulating evidence suggests that aberrant RNA splicing is a common and driving event in cancer development and progression. Moreover, aberrant splicing events conferring drug/therapy resistance in cancer is far more common than previously envisioned. In this review, aberrant splicing events in cancer-associated genes, namely BCL2L1, FAS, HRAS, CD44, Cyclin D1, CASP2, TMPRSS2-ERG, FGFR2, VEGF, AR and KLF6, will be discussed. Also highlighted are the functional consequences of aberrant splice variants (BCR-Abl35INS, BIM-γ, IK6, p61 BRAF V600E, CD19-∆2, AR-V7 and PIK3CD-S) in promoting resistance to cancer targeted therapy or immunotherapy. To overcome drug resistance, we discuss opportunities for developing novel strategies to specifically target the aberrant splice variants or splicing machinery that generates the splice variants. Therapeutic approaches include the development of splice variant-specific siRNAs, splice switching antisense oligonucleotides, and small molecule inhibitors targeting splicing factors, splicing factor kinases or the aberrant oncogenic protein isoforms.

18.
PLoS One ; 13(10): e0205464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30308012

RESUMO

BACKGROUND: A characteristic pathology of early onset myasthenia gravis is thymic hyperplasia with ectopic germinal centers (GC). However, the mechanisms that trigger and maintain thymic hyperplasia are poorly characterized. Dysregulation of small, non-coding microRNAs (miRNAs) and their target genes has been identified in the pathology of several autoimmune diseases. We assessed the miRNA and mRNA profiles of the MG thymus and have investigated their role in GC formation and maintenance. METHODS: MG thymus samples were assessed by histology and grouped based upon the appearance of GC; GC positive and GC negative. A systems biology approach was used to study the differences between the groups. Our study included miRNA and mRNA profiling, quantitative real-time PCR validation, miRNA target identification, pathway analysis, miRNA-mRNA reciprocal expression pairing and interaction. RESULTS: Thirty-eight mature miRNAs and forty-six annotated mRNA transcripts were differentially expressed between the two groups (>1.5 fold change, ANOVA p<0.05). The miRNAs were found to be involved in immune response pathways and identified in other autoimmune diseases. The cellular and molecular functions of the mRNAs showed involvement in cell death and cell survival, cellular proliferation, cytokine signaling and extra-cellular matrix reorganization. Eleven miRNA and mRNA pairs were reciprocally regulated. The Regulator of G protein Signalling 13 (RGS13), known to be involved in GC regulation, was identified in specimens with GC and was paired with downregulation of miR-452-5p and miR-139-5p. MiRNA target sites were validated by dual luciferase assay. Transfection of miRNA mimics led to down regulation of RGS13 expression in Raji cells. CONCLUSION: Our study indicates a distinct miRNA and mRNA expression pattern in ectopic GC in MG thymus. These miRNAs and mRNAs are involved in regulatory pathways common to inflammation and immune response, cell cycle regulation and anti-apoptotic pathways suggesting their involvement in support of GC formation in the thymus. We demonstrate for the first time that miR-139-5p and miR-452-5p negatively regulate RGS13 expression.


Assuntos
Perfilação da Expressão Gênica/métodos , Centro Germinativo/química , MicroRNAs/genética , Miastenia Gravis/genética , Proteínas RGS/genética , Adulto , Linhagem Celular , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/genética , Transdução de Sinais , Biologia de Sistemas/métodos , Timo , Adulto Jovem
19.
Anal Chem ; 90(12): 7569-7577, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29779368

RESUMO

We report here the fabrication and validation of a novel 3D-printed, automated immunoarray to detect multiple proteins with ultralow detection limits. This low cost, miniature immunoarray employs electrochemiluminescent (ECL) detection measured with a CCD camera and employs touch-screen control of a micropump to facilitate automated use. The miniaturized array features prefilled reservoirs to deliver sample and reagents to a paper-thin pyrolytic graphite microwell detection chip to complete sandwich immunoassays. The detection chip achieves high sensitivity by using single-wall carbon nanotube-antibody conjugates in the microwells and employing massively labeled antibody-decorated RuBPY-silica nanoparticles to generate ECL. The total cost of an array is $0.65, and an eight-protein assay can be done in duplicate for $0.14 per protein with limits of detection (LOD) as low as 78-110 fg mL-1 in diluted serum. The electronic control system costs $210 in components. Utility of the automated immunoarray was demonstrated by detecting an eight-protein prostate cancer biomarker panel in human serum samples in 25 min. The system is well suited to future clinical and point-of-care diagnostic testing and could be used in resource-limited environments.


Assuntos
Automação , Biomarcadores Tumorais/sangue , Técnicas Analíticas Microfluídicas , Nanoestruturas/química , Proteínas de Neoplasias/sangue , Impressão Tridimensional , Neoplasias da Próstata/sangue , Linhagem Celular Tumoral , Humanos , Masculino , Técnicas Analíticas Microfluídicas/instrumentação , Impressão Tridimensional/instrumentação , Neoplasias da Próstata/diagnóstico
20.
Carcinogenesis ; 39(7): 879-888, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29726910

RESUMO

Prostate cancer (PCa) is a clinically and molecularly heterogeneous disease, with variation in outcomes only partially predicted by grade and stage. Additional tools to distinguish indolent from aggressive disease are needed. Phenotypic characteristics of stemness correlate with poor cancer prognosis. Given this correlation, we identified single-nucleotide polymorphisms (SNPs) of stemness-related genes and examined their associations with PCa survival. SNPs within stemness-related genes were analyzed for association with overall survival of PCa in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Significant SNPs predicted to be functional were selected for linkage disequilibrium analysis and combined and stratified analyses. Identified SNPs were evaluated for association with gene expression. SNPs of CD44 (rs9666607), ABCC1 (rs35605 and rs212091) and GDF15 (rs1058587) were associated with PCa survival and predicted to be functional. A role for rs9666607 of CD44 and rs35605 of ABCC1 in RNA splicing regulation, rs212091 of ABCC1 in miRNA binding site activity and rs1058587 of GDF15 in causing an amino acid change was predicted. These SNPs represent potential novel prognostic markers for overall survival of PCa and support a contribution of the stemness pathway to PCa patient outcome.


Assuntos
Predisposição Genética para Doença/genética , MicroRNAs/genética , Oncogenes/genética , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , Splicing de RNA/genética , Transdução de Sinais/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinogênese/genética , Fator 15 de Diferenciação de Crescimento/genética , Humanos , Receptores de Hialuronatos/genética , Masculino , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Próstata/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA