Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Type of study
Publication year range
1.
Clin Exp Immunol ; 193(3): 327-340, 2018 09.
Article in English | MEDLINE | ID: mdl-29745428

ABSTRACT

Ovarian cancers are known to evade immunosurveillance and to orchestrate a suppressive immune microenvironment. Here we examine the role of human epididymis protein 4 (HE4), an ovarian cancer biomarker, in immune evasion. Through modified subtractive hybridization analyses we have characterized the gene targets of HE4 in human peripheral blood mononuclear cells (PBMCs), and established a preliminary mechanism for HE4-mediated immune failure in ovarian tumours. Upon exposure of purified PMBCs to HE4, osteopontin (OPN) and dual-specificity phosphatase 6 (DUSP6) emerged as the most suppressed and up-regulated genes, respectively. SKOV3 and OVCAR8, human ovarian carcinoma cell lines, exhibited enhanced proliferation in conditioned media from HE4-exposed PBMCs, an effect that was attenuated by the addition of recombinant OPN or OPN-inducible cytokines [interleukin (IL)-12 and interferon (IFN)-Ɣ]. Additionally, upon co-culture with PBMCs, HE4-silenced SKOV3 cells were found to be more susceptible to cytotoxic cell death. The relationship between HE4 and OPN was reinforced further through the analysis of serous ovarian cancer patient samples. In these biopsy specimens, the number of OPN+ T cells correlated positively with progression free survival (PFS) and inversely with serum HE4 level. Taken together, these findings show that HE4 enhances ovarian cancer tumorigenesis by compromising OPN-mediated T cell activation.


Subject(s)
Dual Specificity Phosphatase 6/metabolism , Leukocytes, Mononuclear/physiology , Osteopontin/metabolism , Ovarian Neoplasms/immunology , Proteins/metabolism , T-Lymphocytes/immunology , Cell Line, Tumor , Cell Proliferation , Cytotoxicity, Immunologic , Dual Specificity Phosphatase 6/genetics , Female , Gene Expression Regulation , Humans , Immune Tolerance , Interferon-gamma/metabolism , Interleukin-12/metabolism , Osteopontin/genetics , Ovarian Neoplasms/mortality , Proteins/genetics , RNA, Small Interfering/genetics , Survival Analysis , Tumor Escape , Tumor Microenvironment , WAP Four-Disulfide Core Domain Protein 2
2.
Arq. bras. med. vet. zootec. (Online) ; 69(6): 1607-1614, nov.-dez. 2017. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-910792

ABSTRACT

Objetivou-se avaliar a teofilina como agente capacitante substituto ou associado à heparina sobre a reação acrossômica dos espermatozoides e o desenvolvimento de embriões produzidos in vitro. O experimento foi realizado com quatro touros e três tratamentos, totalizando 12 grupos experimentais. O sêmen dos touros foi avaliado nos tratamentos descritos a seguir: tratamento 1 (HEP): heparina - 10µg/mL; tratamento 2 (TEO): teofilina - 5mM; tratamento 3 (HEP + TEO): heparina (10µg/mL) + teofilina (5mM), por zero, seis, 12 e 18 horas, corados com trypan blue/Giemsa para avaliação da reação acrossômica. Para a produção dos embriões, os agentes capacitantes foram adicionados aos meios de fertilização. Na análise espermática, a taxa de reação acrossômica verdadeira foi maior (P<0,05) no tempo zero hora, enquanto para espermatozoides mortos, as maiores taxas (P<0,05) foram nos tempos de 12h (84,46±5,82) e 18h (86,75±4,19). A taxa de embriões produzidos (37,97±13) e a taxa de eclosão (33,50±14) foram maiores (P<0,05) para o tratamento HEP. Não foi observada diferença (P>0,05) entre touros na análise de reação acrossômica nem na PIVE. A utilização da teofilina foi tão eficiente quanto a da heparina na indução da reação acrossômica, no entanto resultou em menores taxas de produção embrionária.(AU)


The sperm capacitating process should take special attention during in vitro embryo production (IVEP) once that affects the success of embryo production. The study aimed to evaluate theophylline as substitute capacitating agent or in combination with heparin on the sperm acrosome reaction and development of embryos produced in vitro. The experiment was carried out using 4 bulls and 3 treatments, establishing 12 experimental groups. Each bull was evaluated in the following treatments: Treatment 1 (HEP): Heparin - 10mg/mL; Treatment 2 (THEO): Theophylline - 5mM; Treatment 3 (HEP + THEO), Heparin (10mg/mL) + Theophylline (5mM). The semen of bulls was incubated in each treatment for 0, 6, 12 and 18h, stained with Trypan blue / Giemsa and analyzed by electron microscopy for assessment of acrosome reaction. Using sperm of same bulls, capacitating agents were added to the fertilization media, for IVEP. In sperm analysis, the true acrosome reaction rate was higher (P<0.05) in time 0h, while sperm dead rates were highest (P<0.05) at 12h (84.46±5, 82), and 18h (86.75±4.19). The produced embryos rate (37.97±13) and hatching rate (33.50±14) were larger (P<0.05) for HEP treatment. There was no difference (P>0.05) between bulls in acrosome reaction analysis neither for IVEP. The use of theophylline was as effective as heparin in the induction of the acrosome reaction, although it resulted in lower embryo production rates.(AU)


Subject(s)
Animals , Male , Cattle , Acrosome Reaction , Heparin , Semen , Spermatozoa , Theophylline/therapeutic use
3.
Nat Commun ; 7: 13029, 2016 10 04.
Article in English | MEDLINE | ID: mdl-27701378

ABSTRACT

Photoreceptor replacement by transplantation is proposed as a treatment for blindness. Transplantation of healthy photoreceptor precursor cells into diseased murine eyes leads to the presence of functional photoreceptors within host retinae that express an array of donor-specific proteins. The resulting improvement in visual function was understood to be due to donor cells integrating within host retinae. Here, however, we show that while integration occurs the majority of donor-reporter-labelled cells in the host arises as a result of material transfer between donor and host photoreceptors. Material transfer does not involve permanent donor-host nuclear or cell-cell fusion, or the uptake of free protein or nucleic acid from the extracellular environment. Instead, RNA and/or protein are exchanged between donor and host cells in vivo. These data require a re-evaluation of the mechanisms underlying rescue by photoreceptor transplantation and raise the possibility of material transfer as a strategy for the treatment of retinal disorders.


Subject(s)
Photoreceptor Cells, Vertebrate/transplantation , Retina/transplantation , Retinal Diseases/therapy , Animals , Female , Green Fluorescent Proteins/metabolism , Male , Mice , Mice, Inbred C57BL , Microscopy, Confocal , NIH 3T3 Cells , RNA/metabolism , Retinal Degeneration/metabolism , Retinal Rod Photoreceptor Cells/metabolism , Stem Cell Transplantation , Tissue Donors
4.
J Ovarian Res ; 9(1): 28, 2016 May 17.
Article in English | MEDLINE | ID: mdl-27184254

ABSTRACT

BACKGROUND: Chemotherapy resistance presents a difficult challenge in treating epithelial ovarian cancer patients, particularly when tumors exhibit resistance to multiple chemotherapeutic agents. A few studies have shown that elevated serum levels of the ovarian cancer biomarker HE4 correlate with tumor chemoresistance, response to treatment, and survival. Here, we sought to confirm our previous results that HE4 contributes to collateral resistance to cisplatin and paclitaxel in vitro and uncover factors that may contribute to HE4-mediated chemoresistance. METHODS: MTS assays and western blots for cleaved PARP were used to assess resistance of HE4-overexpressing SKOV3 and OVCAR8 clones to cisplatin and paclitaxel. CRISPR/Cas technology was used to knockdown HE4 in HE4-overexpressing SKOV3 cells. A microarray was conducted to determine differential gene expression between SKOV3 null vector-transfected and HE4-overexpressing clones upon cisplatin exposure, and results were validated by quantitative RT-PCR. Regulation of mitogen activated protein kinases (MAPKs) and tubulins were assessed by western blot. RESULTS: HE4-overexpressing SKOV3 and OVCAR8 clones displayed increased resistance to cisplatin and paclitaxel. Knockdown of HE4 in HE4-overexpressing SKOV3 cells partially reversed chemoresistance. Microarray analysis revealed that HE4 overexpression resulted in suppression of cisplatin-mediated upregulation of EGR1, a MAPK-regulated gene involved in promoting apoptosis. Upregulation of p38, a MAPK activated in response to cisplatin, was suppressed in HE4-overexpressing clones. No differences in extracellular signal-regulated kinase (ERK) activation were noted in HE4-overexpressing clones treated with 25 µM cisplatin, but ERK activation was partially suppressed in HE4-overexpressing clones treated with 80 µM cisplatin. Furthermore, treatment of cells with recombinant HE4 dramatically affected ERK activation in SKOV3 and OVCAR8 wild type cells. Recombinant HE4 also upregulated α-tubulin and ß-tubulin levels in SKOV3 and OVCAR8 cells, and microtubule associated protein tau (MAPT) gene expression was increased in SKOV3 HE4-overexpressing clones. CONCLUSIONS: Overexpression of HE4 promotes collateral resistance to cisplatin and paclitaxel, and downregulation of HE4 partially reverses this chemoresistance. Multiple factors could be involved in HE4-mediated chemoresistance, including deregulation of MAPK signaling, as well as alterations in tubulin levels or stability.


Subject(s)
Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , Drug Resistance, Neoplasm/genetics , Ovarian Neoplasms/genetics , Paclitaxel/pharmacology , Proteins/genetics , Apoptosis/drug effects , CRISPR-Cas Systems , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Down-Regulation , Female , Gene Expression , Gene Expression Regulation, Neoplastic/drug effects , Humans , MAP Kinase Signaling System , Ovarian Neoplasms/metabolism , Tubulin/metabolism , WAP Four-Disulfide Core Domain Protein 2 , tau Proteins/genetics , tau Proteins/metabolism
5.
Genet Mol Res ; 11(3): 2476-86, 2012 Aug 16.
Article in English | MEDLINE | ID: mdl-22653651

ABSTRACT

Belostoma, a genus of the family Belostomatidae, includes species of great ecological importance as biocontrol agents. Few species of these species have been the subject of cytogenetic analyses. Karyotypic evolution in this genus involves agmatoploidy and simploidy; there are also different sex chromosome systems. We examined two Belostoma species (B. dilatatum and B. candidulum) collected from the Paranapanema River Basin (Brazil). Mitotic and meiotic analysis revealed 2n(♂) = 26 + X1X2X3Y for B. dilatatum and 2n(♂) = 14 + XY for B. candidulum; both karyotypes have holokinetic chromosomes. Differences in heterochromatin distribution were also observed between the species, besides variation in the localization of CMA3⁺/DAPI⁻ blocks. The existence of different types of sex chromosome systems in these species was confirmed based on arrangements of the chromosomes in different meiotic stages. We identified a new sex system in B. dilatatum, and make the first cytogenetic report on B. candidulum.


Subject(s)
Heteroptera/genetics , Sex Chromosomes/genetics , Animals , Evolution, Molecular , Female , Fluorescent Dyes/metabolism , Karyotyping , Male , Meiosis/genetics , Staining and Labeling
6.
Environ Microbiol ; 1(5): 401-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-11207759

ABSTRACT

Pyrolysis mass spectrometry (PyMS) and DNA fingerprinting (RAPD and RSalpha hybridization) were used to characterize soybean inoculant strains and root nodule isolates of bradyrhizobia from the Brazilian Cerrado soils. Most isolates were shown to be derived from the inoculant strains on the basis of genotype comparisons by DNA fingerprinting. Phenotypic analysis (using PyMS) of the strains and separately of the polysaccharides derived from them showed that the nodule isolates differed from the parental strains, suggesting adaptation to the Cerrado soil environment. The extent of the differences between the derivatives and inoculant strains was similar for comparisons made on the basis of whole-cell preparations or from the isolated polysaccharides, indicating that the adaptation was caused by changes in the composition of the polysaccharides produced.


Subject(s)
Adaptation, Physiological , Bradyrhizobium/growth & development , Bradyrhizobium/genetics , Glycine max/microbiology , Polysaccharides, Bacterial/chemistry , Soil Microbiology , Bradyrhizobium/chemistry , Brazil , Mass Spectrometry/methods , Nucleic Acid Hybridization , Polysaccharides, Bacterial/genetics , Polysaccharides, Bacterial/metabolism , Random Amplified Polymorphic DNA Technique
SELECTION OF CITATIONS
SEARCH DETAIL
...