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1.
Immunology ; 163(1): 105-111, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33502012

RESUMO

Whether resident and recruited myeloid cells may impair or aid healing of acute skin wounds remains a debated question. To begin to address this, we examined the importance of CD11c+ myeloid cells in the early activation of skin wound repair. We find that an absence of CD11c+ cells delays wound closure and epidermal proliferation, likely due to defects in the activation of the IL-23-IL-22 axis that is required for wound healing.


Assuntos
Antígenos CD11/deficiência , Células Dendríticas/imunologia , Pele/imunologia , Cicatrização , Ferimentos e Lesões/imunologia , Animais , Antígenos CD11/genética , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Cinética , Células de Langerhans/imunologia , Células de Langerhans/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pele/metabolismo , Pele/patologia , Ferimentos e Lesões/genética , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
2.
BMC Urol ; 20(1): 187, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33238953

RESUMO

BACKGROUND: Bladder cancer (BC) is the 10th most common cancer in the UK, with about 10,000 new cases annually. About 75-85% of BC are non-muscle invasive (NMIBC), which is associated with high recurrence and progression rates (50-60% within 7-10 years). There are no routine biomarkers currently available for identifying BC patients at increased risk of developing recurrence. The focus of this research study was to evaluate antibody expression in BC patients and their association with cancer recurrence. METHODS: 35 patients scheduled for TURBT were recruited after written informed consent. Ethical approval for the project was granted via IRAS (REC4: 14/WA/0033). Following surgical procedure, tissues were preserved in 10% buffered formalin and processed within 24 h in FFPE blocks. 7 sections (4 µm each) were cut from each block and stained for CD31, Human epidermal growth factor receptor-2 (HER-2), S100P, Cyclooxygenase-2 (COX-2), VEGFR-3 thrombomodulin and CEACAM-1 using immunohistochemistry. Clinical outcome measures (obtained via cystoscopy) were monitored for up to 6 months following surgical procedure. RESULTS: There was significantly increased expression of CD31 (p < 0.001), HER-2 (p = 0.032), S100P (p < 0.001), COX-2 (p < 0.001), VEGFR-3 (p < 0.001) and decreased expression of thrombomodulin (p = 0.010) and CEACAM-1 (p < 0.001) in bladder tumours compared to normal bladder tissues. HER-2 expression was also significantly associated with cancer grade (p = 0.003), especially between grade 1 and grade 2 (p = 0.002) and between grade 1 and grade 3 (p = 0.004). There was also a significant association between cancer stage and HER-2 expression (p < 0.001). Although recurrence was significantly associated with cancer grade, there was no association with antibody expression. CONCLUSION: Findings from the present study may indicate an alternative approach in the monitoring and management of patients with BC. It is proposed that by allowing urological surgeons access to laboratory markers such as HER-2, Thrombomodulin and CD31 (biomarker profile), potentially, in the future, these biomarkers may be used in addition to, or in combination with, currently used scoring systems to predict cancer recurrence. However, verification and validation of these biomarkers are needed using larger cohorts.


Assuntos
Formação de Anticorpos , Recidiva Local de Neoplasia/imunologia , Neoplasias da Bexiga Urinária/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos
3.
BMC Urol ; 20(1): 122, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32795278

RESUMO

BACKGROUND: The number of patients diagnosed and subsequently treated for kidney stones is increasing, and as such the number of post-operative complications is likely to increase. At present, little is known about the role of specific biomarkers, following flexible ureterorenoscopy (FURS) for the surgical treatment of kidney stones. The main aim of the study was to evaluate the role of kidney and infection biomarkers, in patients undergoing FURS. METHODS: Included were 37 patients (24 males, 13 females), who underwent elective FURS, for the treatment of kidney stones. Venous blood samples were collected from each patient: pre-operatively, and at 30 min, 2 and 4 h post-operatively. Changes to kidney (NGAL, Cystatin-C) and infection (MPO, PCT) biomarkers was quantified by means of ELISA, Biomerieux mini-vidas and Konelab 20 analysers. RESULTS: Four patients developed post-operative complications (3 - UTIs with urinary retention, 1 - urosepsis. NGAL concentration increased significantly following FURS (p = 0.034). Although no significant changes were seen in Cystatin C, MPO and PCT (p ≥ 0.05) some key clinical observation were noted. Limiting factors for this study were the small number of patients recruited and restriction in blood sampling beyond 4 h. CONCLUSIONS: Although not confirmative, changes seen to biomarkers such as Cystatin C, NGAL and MPO in our observational clinical pilot-study may warrant further investigation, involving larger cohorts, to fully understand the role of these biomarkers and their potential association with post-operative complications which can develop following FURS.


Assuntos
Cálculos Renais/cirurgia , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/epidemiologia , Ureteroscopia , Infecções Urinárias/sangue , Infecções Urinárias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Ureteroscópios , Ureteroscopia/métodos
4.
J Mammary Gland Biol Neoplasia ; 24(3): 245-256, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31529195

RESUMO

Triple negative breast cancer (TNBC) is the most lethal breast cancer subtype. Extended periods of lactation protect against breast cancer development, but the mechanisms underlying this protection are unknown. We examined the effects of the milk protein alpha-casein over expression in the triple negative MDA-MB-231 breast cancer cell line. The effects of recombinant alpha-casein added exogenously to MDA-MB-231 breast cancer cells, and immortalised human fibroblasts were also investigated. We used transcriptional reporters to understand the signalling pathways downstream of alpha-casein in breast cancer cells and these fibroblasts that were activated by breast cancer cells. To extend our findings to the clinical setting, we analysed public gene expression datasets to further understand the relevance of these signalling pathways in triple negative breast cancer cells and patient samples. Finally, we used small molecular inhibitors to target relevant pathways and highlight these as potential candidates for the treatment of TN breast cancer. High levels of alpha-casein gene expression were predictive of good prognosis across 263 TNBC patient tumour samples. Alpha-casein over expression or exogenous addition reduces cancer stem cell (CSC) activity. HIF-1alpha was identified to be a key downstream target of alpha-casein, in both breast cancer cells and activated fibroblasts, and STAT transcription factors to be upstream of HIF-1alpha. Interestingly, HIF-1alpha is regulated by STAT3 in breast cancer cells, but STAT1 is the regulator of HIF-1alpha in activated fibroblasts. In analysis of 573 TNBC patient samples, alpha-casein expression, inversely correlated to HIF-1alpha, STAT3 and STAT1. STAT1 and STAT3 inhibitors target HIF-1alpha signalling in activated fibroblasts and MDA-MB-231 breast cancer cells respectively, and also abrogate CSC activities. Our findings provide an explanation for the protective effects of lactation in TNBC. Clinical data correlates high alpha-casein expression with increased recurrence-free survival in TNBC patients. Mechanistically, alpha-casein reduces breast cancer stem cell activity in vitro, and STAT3 and STAT1 were identified as regulators of pro-tumorigenic HIF-1alpha signalling in breast cancer cells and fibroblasts respectively.


Assuntos
Biomarcadores Tumorais/metabolismo , Caseínas/metabolismo , Fibroblastos/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Neoplásicas/patologia , Fator de Transcrição STAT3/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Biomarcadores Tumorais/genética , Caseínas/genética , Proliferação de Células , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/genética , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Células Tumorais Cultivadas
5.
Plant Cell ; 26(1): 465-84, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24415770

RESUMO

The Mediator16 (MED16; formerly termed SENSITIVE TO FREEZING6 [SFR6]) subunit of the plant Mediator transcriptional coactivator complex regulates cold-responsive gene expression in Arabidopsis thaliana, acting downstream of the C-repeat binding factor (CBF) transcription factors to recruit the core Mediator complex to cold-regulated genes. Here, we use loss-of-function mutants to show that RNA polymerase II recruitment to CBF-responsive cold-regulated genes requires MED16, MED2, and MED14 subunits. Transcription of genes known to be regulated via CBFs binding to the C-repeat motif/drought-responsive element promoter motif requires all three Mediator subunits, as does cold acclimation-induced freezing tolerance. In addition, these three subunits are required for low temperature-induced expression of some other, but not all, cold-responsive genes, including genes that are not known targets of CBFs. Genes inducible by darkness also required MED16 but required a different combination of Mediator subunits for their expression than the genes induced by cold. Together, our data illustrate that plants control transcription of specific genes through the action of subsets of Mediator subunits; the specific combination defined by the nature of the stimulus but also by the identity of the gene induced.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Complexo Mediador/fisiologia , RNA Polimerase II/metabolismo , Transativadores/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas e Peptídeos de Choque Frio/genética , Complexo Mediador/genética , Complexo Mediador/metabolismo , Transativadores/genética , Transativadores/metabolismo
6.
Plant Cell ; 23(11): 4079-95, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22086087

RESUMO

Increases in intracellular calcium concentration ([Ca(2+)](c)) mediate plant responses to stress by regulating the expression of genes encoding proteins that confer tolerance. Several plant stress genes have previously been shown to be calcium-regulated, and in one case, a specific promoter motif Abscisic Acid Responsive-Element (ABRE) has been found to be regulated by calcium. A comprehensive survey of the Arabidopsis thaliana transcriptome for calcium-regulated promoter motifs was performed by measuring the expression of genes in Arabidopsis seedlings responding to three calcium elevations of different characteristics, using full genome microarray analysis. This work revealed a total of 269 genes upregulated by [Ca(2+)](c) in Arabidopsis. Bioinformatic analysis strongly indicated that at least four promoter motifs were [Ca(2+)](c)-regulated in planta. We confirmed this finding by expressing in plants chimeric gene constructs controlled exclusively by these cis-elements and by testing the necessity and sufficiency of calcium for their expression. Our data reveal that the C-Repeat/Drought-Responsive Element, Site II, and CAM box (along with the previously identified ABRE) promoter motifs are calcium-regulated. The identification of these promoter elements targeted by the second messenger intracellular calcium has implications for plant signaling in response to a variety of stimuli, including cold, drought, and biotic stress.


Assuntos
Arabidopsis/genética , Cálcio/metabolismo , Regulação da Expressão Gênica de Plantas , Regiões Promotoras Genéticas , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Dendrímeros , Estimulação Elétrica , Perfilação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos/farmacologia , Sequências Reguladoras de Ácido Nucleico , Elementos de Resposta/genética , Venenos de Vespas/farmacologia
7.
Plant J ; 71(5): 736-49, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22507399

RESUMO

The floral meristem identity gene LEAFY (LFY) of Arabidopsis thaliana is essential for the formation of fertile flowers and has roles in the control of several aspects of floral development, which include phyllotaxy and organ number and identity. This gene encodes a land plant-specific transcription factor and regulates expression of a number of genes that include other floral meristem identity genes and floral homeotic genes. Although the LFY DNA-binding domain has a structure that resembles that of helix-turn-helix proteins, LFY and its orthologs represent a novel family of transcription factors that are characterized by a conserved N-terminus domain of unknown function and a C-terminus DNA-binding domain. Many transcription factors act as dimers. These dimers are essential for the biological activity of the proteins. We demonstrate that LFY forms homodimers or oligomers in solution. This association is mediated through the N-terminus conserved region of the LFY protein. Although mutant LFY proteins that cannot dimerize in solution can bind DNA, the binding is weaker than that of wild type LFY protein. LFY-LFY interactions mediated by the N-terminus domain are essential for the biological activity of this protein, as mutations that abolish the ability to self-associate cannot complement an lfy null allele. Our data indicate: (i) that LFY, and probably its orthologs in other plants, must act in complexes that contain at least two LFY molecules; and (ii) that the N-terminus is essential for stabilization of LFY complexes. This situation is integral to the ability of LFY to regulate gene expression.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência Conservada , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Multimerização Proteica , Estrutura Terciária de Proteína , Fatores de Transcrição/genética
8.
BMC Plant Biol ; 13: 1, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23280064

RESUMO

BACKGROUND: The Arabidopsis thaliana gene SPATULA (SPT), encoding a bHLH transcription factor, was originally identified for its role in pistil development. SPT is necessary for the growth and development of all carpel margin tissues including the style, stigma, septum and transmitting tract. Since then, it has been shown to have pleiotropic roles during development, including restricting the meristematic region of the leaf primordia and cotyledon expansion. Although SPT is expressed in roots, its role in this organ has not been investigated. RESULTS: An analysis of embryo and root development showed that loss of SPT function causes an increase in quiescent center size in both the embryonic and postembryonic stem cell niches. In addition, root meristem size is larger due to increased division, which leads to a longer primary root. spt mutants exhibit other pleiotropic developmental phenotypes, including more flowers, shorter internodes and an extended flowering period. Genetic and molecular analysis suggests that SPT regulates cell proliferation in parallel to gibberellic acid as well as affecting auxin accumulation or transport. CONCLUSIONS: Our data suggest that SPT functions in growth control throughout sporophytic growth of Arabidopsis, but is not necessary for cell fate decisions except during carpel development. SPT functions independently of gibberellic acid during root development, but may play a role in regulating auxin transport or accumulation. Our data suggests that SPT plays a role in control of root growth, similar to its roles in above ground tissues.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Meristema/genética , Meristema/metabolismo , Raízes de Plantas/genética
9.
Cell Mol Life Sci ; 69(2): 175-89, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21861184

RESUMO

Poly(ADP-ribosyl)ation is the covalent attachment of ADP-ribose subunits from NAD(+) to target proteins and was first described in plants in the 1970s. This post-translational modification is mediated by poly(ADP-ribose) polymerases (PARPs) and removed by poly(ADP-ribose) glycohydrolases (PARGs). PARPs have important functions in many biological processes including DNA repair, epigenetic regulation and transcription. However, these roles are not always associated with enzymatic activity. The PARP superfamily has been well studied in animals, but remains under-investigated in plants. Although plants lack the variety of PARP superfamily members found in mammals, they do encode three different types of PARP superfamily proteins, including a group of PARP-like proteins, the SRO family, that are plant specific. In plants, members of the PARP family and/or poly(ADP-ribosyl)ation have been linked to DNA repair, mitosis, innate immunity and stress responses. In addition, members of the SRO family have been shown to be necessary for normal sporophytic development. In this review, we summarize the current state of plant research into poly(ADP-ribosyl)ation and the PARP superfamily in plants.


Assuntos
Proteínas de Plantas/metabolismo , Plantas/enzimologia , Poli(ADP-Ribose) Polimerases/metabolismo , Sequência de Aminoácidos , Ciclo Celular , Reparo do DNA , Dados de Sequência Molecular , Desenvolvimento Vegetal , Processamento de Proteína Pós-Traducional , Estresse Fisiológico
10.
Cancer Med ; 12(16): 17184-17192, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37455592

RESUMO

BACKGROUND/AIM: Clotting factors promote cancer development. We investigated if coagulation proteins promote proliferation and migration in colorectal cancer (CRC) cell lines and whether their direct inhibitors can attenuate these effects. MATERIALS AND METHODS: DLD-1 and SW620 cells were treated with tissue factor (0, 50, 100 and 500 pg/mL ± 10 µg/mL 10H10 [anti-tissue factor antibody]), thrombin (0.0, 0.1, 1.0 and 10.0 U/mL ± 0.5 µM dabigatran [thrombin inhibitor]) and Factor Xa, FXa (0.0, 0.1, 1.0 and 10.0 U/mL ± 100 ng/mL rivaroxaban [FXa inhibitor]) and their effects on proliferation and migration were quantified using the PrestoBlue® and transwell migration assays, respectively. RESULTS: Thrombin increased proliferation from 48 h treatment compared to its control (48 h 6.57 ± 1.36 u vs. 2.42 ± 0.13 u, p = 0.001, 72 h 9.50 ± 1.54 u vs. 4.50 ± 0.47 u, p = 0.004 and 96 h 10.77 ± 1.72 u vs. 5.57 ± 0.25 u, p = 0.008). This increase in proliferation was attenuated by dabigatran at 72 h (2.23 ± 0.16 u vs. 3.26 ± 0.43 u, p = 0.04). Tissue factor (0 pg/mL 20.7 ± 1.6 cells/view vs. 50 pg/mL 32.4 ± 1.9 cells/view, p = 0.0002), FXa (0.0 U/mL 8.9 ± 1.1 cells/view vs. 10.0 U/mL 17.7 ± 1.7 cells/view, p < 0.0001) and thrombin (0.0 U/mL 8.9 ± 1.3 cells/view vs. 10.0 U/mL 20.2 ± 2.0 cells/view, p < 0.0001) all increased migration compared to their controls. However, their direct inhibitors did not attenuate these increases. CONCLUSION: Thrombin, FXa and TF all increase migration in CRC in vitro. Thrombin induced increase in proliferation is abrogated by dabigatran. Dabigatran may have potential as an anti-cancer therapy in CRC.


Assuntos
Neoplasias Colorretais , Dabigatrana , Humanos , Dabigatrana/farmacologia , Dabigatrana/uso terapêutico , Trombina/metabolismo , Inibidores do Fator Xa/farmacologia , Fatores de Coagulação Sanguínea/farmacologia , Tromboplastina/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Proliferação de Células
11.
J Exp Bot ; 63(15): 5545-58, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22915737

RESUMO

Gamete formation is an important step in the life cycle of sexually reproducing organisms. In flowering plants, haploid spores are formed after the meiotic division of spore mother cells. These spores develop into male and female gametophytes containing gametes after undergoing mitotic divisions. In the female, the megaspore mother cell undergoes meiosis forming four megaspores, of which one is functional and three degenerate. The megaspore then undergoes three mitotic cycles thus generating an embryo sac with eight nuclei. The embryo sac undergoes cellularization to form the mature seven-celled female gametophyte. Entry into and progression through meiosis is essential for megasporogenesis and subsequent megagametogenesis, but control of this process is not well understood. FOUR LIPS (FLP) and its paralogue MYB88, encoding R2R3 MYB transcription factors, have been extensively studied for their role in limiting the terminal division in stomatal development by direct regulation of the expression of cell cycle genes. Here it is demonstrated that FLP and MYB88 also regulate female reproduction. Both FLP and MYB88 are expressed during ovule development and their loss significantly increases the number of ovules produced by the placenta. Despite the presence of excess ovules, single and double mutants exhibit reduced seed set due to reduced female fertility. The sterility results at least in part from defective meiotic entry and progression. Therefore, FLP and MYB88 are important regulators of entry into megasporogenesis, and probably act via the regulation of cell cycle genes.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Gametogênese Vegetal/genética , Regulação da Expressão Gênica de Plantas/genética , Meiose/genética , Fatores de Transcrição/genética , Arabidopsis/citologia , Arabidopsis/embriologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclo Celular , Flores/citologia , Flores/embriologia , Flores/genética , Flores/fisiologia , Genótipo , Mutação , Óvulo Vegetal/citologia , Óvulo Vegetal/embriologia , Óvulo Vegetal/genética , Óvulo Vegetal/fisiologia , Tubo Polínico/citologia , Tubo Polínico/embriologia , Tubo Polínico/genética , Tubo Polínico/fisiologia , Proteínas Recombinantes de Fusão , Reprodução , Sementes/citologia , Sementes/embriologia , Sementes/genética , Sementes/fisiologia , Fatores de Transcrição/metabolismo
12.
Am J Pathol ; 177(6): 2886-97, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20971731

RESUMO

The oncogene cyclin D1 is highly expressed in many breast cancers and, despite its proliferation-activating properties, it has been linked to a less malignant phenotype. To clarify this observation, we focused on two key components of malignant behavior, migration and proliferation, and observed that quiescent G(0)/G(1) cells display an increased migratory capacity compared to cycling cells. We also found that the down-regulation of cyclin D1 in actively cycling cells significantly increased migration while also decreasing proliferation. When analyzing a large set of premenopausal breast cancers, we observed an inverse proliferation-independent link between cyclin D1 and tumor size and recurrence, suggesting that this protein might abrogate infiltrative malignant behavior in vivo. Finally, gene expression analysis after cyclin D1 down-regulation by siRNA confirmed changes in processes associated with migration and enrichment of our gene set in a metastatic poor prognosis signature. This novel function of cyclin D1 illustrates the interplay between tumor proliferation and migration and may explain the attenuation of malignant behavior in breast cancers with high cyclin D1 levels.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Carcinoma/diagnóstico , Carcinoma/genética , Movimento Celular/genética , Ciclina D1/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/fisiologia , Neoplasias da Mama/patologia , Carcinoma/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células , Ciclina D1/antagonistas & inibidores , Ciclina D1/metabolismo , Ciclina D1/fisiologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Análise em Microsséries , Invasividade Neoplásica , Oncogenes/genética , Oncogenes/fisiologia , Prognóstico , RNA Interferente Pequeno/farmacologia , Células Tumorais Cultivadas , Regulação para Cima
13.
J Exp Bot ; 62(3): 1271-84, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21172813

RESUMO

The radical-induced cell death1 and similar to RCD ONE1 genes of Arabidopsis thaliana encode members of the poly(ADP-ribose) polymerase (PARP) superfamily and have pleiotropic functions in development and abiotic stress response. In order to begin to understand the developmental and molecular bases of the defects seen in rcd1-3; sro1-1 plants, this study used the root as a model. Double mutant roots are short and display abnormally organized root apical meristems. However, acquisition of most cell fates within the root is not significantly disrupted. The identity of the quiescent centre is compromised, the zone of cell division is smaller than in wild-type roots and abnormal divisions are common, suggesting that RCD1 and SRO1 are necessary to maintain cells in a division-competent state and to regulate division plane placement. In addition, differentiation of several cell types is disrupted in rcd1-3; sro1-1 roots and shoots, demonstrating that RCD1 and SRO1 are also necessary for proper cell differentiation. Based on the data shown in this article and previous work, we hypothesize that RCD1 and SRO1 are involved in redox control and, in their absence, an altered redox balance leads to abnormal development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Meristema/metabolismo , Proteínas Nucleares/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Diferenciação Celular , Divisão Celular , Meristema/citologia , Meristema/genética , Proteínas Nucleares/genética , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
14.
BMC Evol Biol ; 10: 308, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20942953

RESUMO

BACKGROUND: The poly(ADP-ribose) polymerase (PARP) superfamily was originally identified as enzymes that catalyze the attachment of ADP-ribose subunits to target proteins using NAD+ as a substrate. The family is characterized by the catalytic site, termed the PARP signature. While these proteins can be found in a range of eukaryotes, they have been best studied in mammals. In these organisms, PARPs have key functions in DNA repair, genome integrity and epigenetic regulation. More recently it has been found that proteins within the PARP superfamily have altered catalytic sites, and have mono(ADP-ribose) transferase (mART) activity or are enzymatically inactive. These findings suggest that the PARP signature has a broader range of functions that initially predicted. In this study, we investigate the evolutionary history of PARP genes across the eukaryotes. RESULTS: We identified in silico 236 PARP proteins from 77 species across five of the six eukaryotic supergroups. We performed extensive phylogenetic analyses of the identified PARPs. They are found in all eukaryotic supergroups for which sequence is available, but some individual lineages within supergroups have independently lost these genes. The PARP superfamily can be subdivided into six clades. Two of these clades were likely found in the last common eukaryotic ancestor. In addition, we have identified PARPs in organisms in which they have not previously been described. CONCLUSIONS: Three main conclusions can be drawn from our study. First, the broad distribution and pattern of representation of PARP genes indicates that the ancestor of all extant eukaryotes encoded proteins of this type. Second, the ancestral PARP proteins had different functions and activities. One of these proteins was similar to human PARP1 and likely functioned in DNA damage response. The second of the ancestral PARPs had already evolved differences in its catalytic domain that suggest that these proteins may not have possessed poly(ADP-ribosyl)ation activity. Third, the diversity of the PARP superfamily is larger than previously documented, suggesting as more eukaryotic genomes become available, this gene family will grow in both number and type.


Assuntos
Eucariotos/enzimologia , Eucariotos/genética , Evolução Molecular , Poli(ADP-Ribose) Polimerases/genética , Animais , Eucariotos/classificação , Humanos , Filogenia , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/classificação , Estrutura Terciária de Proteína
15.
Eur J Med Res ; 25(1): 68, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33308282

RESUMO

BACKGROUND: The number of patients undergoing flexible ureterenoscopy (FURS) for the treatment of kidney stones (renal calculi) is increasing annually, and as such the development of post-operative complications, such as acute kidney injury (AKI), haematuria and infection is likely to increase. Phagocytic leukocytes are white blood cells that help fight foreign material such as bacteria and viruses, and they are intrinsically involved in the inflammatory reaction. Investigating the role of phagocytic leukocytes following FURS has not been widely researched. The main aim of the study was to evaluate the role phagocytic leukocytes (neutrophils and monocytes) function, in patients undergoing FURS for the treatment of kidney stones (renal calculi). METHODS: Fourteen consecutive patients aged between 27 and 70 years (median 49.5 years) undergoing FURS for the treatment of kidney stones were recruited (seven males, seven females). Blood samples were collected from each patient at four time points: baseline (pre-operatively) followed by 30, 120 and 240 min post-operatively. Mononuclear (MN) and polymorphonuclear (PMN) leukocyte sub-populations were isolated by density gradient centrifugation techniques. Neutrophil and monocyte cell function was investigated by measuring the cell surface expression of CD62L (L-selectin), CD11b (Mac-1), CD99 and the intracellular production of hydrogen peroxide (H2O2), via flow cytometry. RESULTS: Significant increases was observed in monocyte CD62L expression post FURS for the treatment of kidney stones (p ≤ 0.05); while significant decreases were observed in neutrophil CD62L. The levels of the other activation markers CD11b, CD99 and H2O2 corresponded to the increases and decreases seen in CD62L for monocytes and neutrophils respectively, though the changes were not statistically significant (p > 0.05). Limiting factors for this study were the relatively small sample size, and restriction on the recruitment time points. CONCLUSIONS: This study demonstrates that following FURS for the treatment of kidney stones, monocytes are rapidly activated and produce potent reactive oxygen intermediates. Interestingly, the pattern of expression in neutrophils suggests that these cells are deactivated in response to the treatment. The leukocyte biomarkers assessed during this investigation may have a role in monitoring the 'normal' post-operative response, as no complications occurred in any of the patients; or may help predict potential infectious complications (e.g. urosepsis) that can occur during the post-operative period. This data, however, will need to be validated and reproduced in larger multi-centre studies.


Assuntos
Cálculos Renais/cirurgia , Leucócitos/fisiologia , Ureteroscopia/métodos , Antígeno 12E7/metabolismo , Adulto , Idoso , Antígeno CD11b/metabolismo , Separação Celular , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Cálculos Renais/patologia , Selectina L/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/fisiologia , Neutrófilos/metabolismo , Neutrófilos/fisiologia , Fagocitose , Projetos Piloto , Ureteroscopia/efeitos adversos
16.
ACS Chem Biol ; 14(3): 369-377, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30707838

RESUMO

Retinoids, such as all- trans-retinoic acid (ATRA), are endogenous signaling molecules derived from vitamin A that influence a variety of cellular processes through mediation of transcription events in the cell nucleus. Because of these wide-ranging and powerful biological activities, retinoids have emerged as therapeutic candidates of enormous potential. However, their use has been limited, to date, due to a lack of understanding of the complex and intricate signaling pathways that they control. We have designed and synthesized a family of synthetic retinoids that exhibit strong, intrinsic, solvatochromatic fluorescence as multifunctional tools to interrogate these important biological activities. We utilized the unique photophysical characteristics of these fluorescent retinoids to develop a novel in vitro fluorometric binding assay to characterize and quantify their binding to their cellular targets, including cellular retinoid binding protein II (CRABPII). The dihydroquinoline retinoid, DC360, exhibited particularly strong binding ( Kd = 34.0 ± 2.5 nM), and we further used X-ray crystallography to determine the structure of the DC360-CRABPII complex to 1.8 Å, which showed that DC360 occupies the known hydrophobic retinoid binding pocket. Finally, we used confocal fluorescence microscopy to image the cellular behavior of the compounds in cultured human epithelial cells, highlighting a fascinating nuclear localization, and used RNA sequencing to confirm that the compounds regulate cellular processes similar to those of ATRA. We anticipate that the unique properties of these fluorescent retinoids can now be used to cast new light on the vital and highly complex retinoid signaling pathway.


Assuntos
Corantes Fluorescentes/química , Retinoides/metabolismo , Proteínas Celulares de Ligação ao Retinol/metabolismo , Tretinoína/química , Tretinoína/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Desenho de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imagem Óptica/métodos , Ligação Proteica , Conformação Proteica , Transdução de Sinais
17.
Chem Sci ; 10(17): 4673-4683, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31123578

RESUMO

Photoactivation of photosensitisers can be utilised to elicit the production of ROS, for potential therapeutic applications, including the destruction of diseased tissues and tumours. A novel class of photosensitiser, exemplified by DC324, has been designed possessing a modular, low molecular weight and 'drug-like' structure which is bioavailable and can be photoactivated by UV-A/405 nm or corresponding two-photon absorption of near-IR (800 nm) light, resulting in powerful cytotoxic activity, ostensibly through the production of ROS in a cellular environment. A variety of in vitro cellular assays confirmed ROS formation and in vivo cytotoxic activity was exemplified via irradiation and subsequent targeted destruction of specific areas of a zebrafish embryo.

18.
Anticancer Res ; 38(5): 2635-2642, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29715083

RESUMO

BACKGROUND/AIM: Tissue factor (TF) expression increases cancer stem cell (CSC) activity in breast and lung cancer. There are ongoing studies focused on targeting CSCs via anti-TF treatment, for breast and lung cancer therapy. Herein, the aim was to determine whether targeting TF could have an anti-CSC therapeutic role in colorectal cancer (CRC). MATERIALS AND METHODS: Evaluation of colonosphere-forming efficiency (CFE) and aldehyde dehydrogenase (ALDH) expression level was used to quantify CSC activity in two CRC cell lines, after TF knockdown (TFKD) or TF over-expression (TFOE). RESULTS: TFKD resulted in increased levels of ALDH in SW620 (1.31±0.04-fold, p<0.001) and DLD-1 (1.63±0.14-fold, p=0.04) cells. CFE was increased in SW620 (1.21±0.23% vs. 2.03±0.29%, p=0.01) and DLD-1 (0.41±0.12% vs. 0.68±0.9%, p=0.01) cells. Conversely, TFOE decreased ALDH expression (0.72±0.04-fold, p=0.001) and CFE (0.33±0.05% vs. 0.66±0.14%, p=0.006) in DLD-1, but had no impact on SW620 cells. CONCLUSION: In the examined CRC cell lines, TF expression was inversely related to CSC activity suggesting that anti-TF therapies may not have a role in CRC treatment.


Assuntos
Neoplasias Colorretais/patologia , Células-Tronco Neoplásicas/patologia , Tromboplastina/fisiologia , Aldeído Desidrogenase/análise , Biomarcadores Tumorais , Divisão Celular , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Vetores Genéticos/farmacologia , Humanos , Lentivirus/genética , Células-Tronco Neoplásicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes/metabolismo , Esferoides Celulares , Tromboplastina/antagonistas & inibidores , Tromboplastina/genética
19.
PLoS One ; 12(7): e0179599, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28683066

RESUMO

BACKGROUND: Currently there is limited research documenting the changes in blood parameters, following Flexible Ureterorenoscopy. This study aims to determine whether there are any changes in haematology and biochemistry parameters, following Flexible Ureterorenoscopy for the treatment of kidney stones. METHODS: 40 consecutive patients aged between 27-87 years (median 49 years) undergoing Flexible Ureterorenoscopy for the treatment of kidney stones were recruited (26 male, 14 female). Blood samples were collected from each patient at four time points: baseline (pre-operatively) followed by 30 minutes, 120 minutes and 240 minutes post-operatively. On these samples, routine haematological and biochemistry tests were carried out. In addition to the assessment of clinical parameters prospectively from the medical notes. RESULTS: There was a significant decrease observed following Flexible Ureterorenoscopy in the following parameters: lymphocytes (p = 0.007), eosinophils (p = 0.001), basophils (p = 0.001), haemoglobin (p = 0.002), red blood cells (p = 0.001), platelet count (p = 0.001), fibrinogen concentration (p = 0.001), von Willebrand factor (p = 0.046), C reactive protein (p = 0.01), total protein (p = 0.001), albumin (p = 0.001), globulin (p = 0.001) and alkaline phosphatase (p = 0.001). In addition, there was a significant increase observed in the following parameters: white blood cells (p = 0.001), neutrophils (p = 0.001), activated partial thromboplastin time (p = 0.001), total bilirubin (p = 0.012), creatinine (p = 0.008), sodium (p = 0.002) and potassium (p = 0.001). Limiting factors for this study were the sample size, and restriction on the recruitment time points. CONCLUSIONS: Significant changes were noted to occur in haematology and biochemistry parameters following Flexible Ureterorenoscopy. Some of the data presented in this study may represent the 'normal' post-operative response following FURS, as no major complications occurred, in the majority of our patients. This data on the 'normal response' will need to be validated but may ultimately aid clinicians in distinguishing patients at risk of complications, if reproduced in larger multi-centre studies.


Assuntos
Cálculos Renais/sangue , Rim/cirurgia , Litotripsia a Laser/métodos , Ureteroscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Contagem de Células Sanguíneas , Proteína C-Reativa/metabolismo , Índices de Eritrócitos , Feminino , Fibrinogênio/metabolismo , Humanos , Rim/patologia , Cálculos Renais/patologia , Cálculos Renais/cirurgia , Litotripsia a Laser/instrumentação , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Albumina Sérica/metabolismo , Ureteroscopia/instrumentação , Fator de von Willebrand/metabolismo
20.
Aging (Albany NY) ; 8(8): 1593-607, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27344270

RESUMO

Bedaquiline (a.k.a., Sirturo) is an anti-microbial agent, which is approved by the FDA for the treatment of multi-drug resistant pulmonary tuberculosis (TB). Bedaquiline is a first-in-class diaryl-quinoline compound, that mechanistically inhibits the bacterial ATP-synthase, and shows potent activity against both drug-sensitive and drug-resistant TB. Interestingly, eukaryotic mitochondria originally evolved from engulfed aerobic bacteria. Thus, we hypothesized that, in mammalian cells, bedaquiline might also target the mitochondrial ATP-synthase, leading to mitochondrial dysfunction and ATP depletion. Here, we show that bedaquiline has anti-cancer activity, directed against Cancer Stem-like Cells (CSCs). More specifically, we demonstrate that bedaquiline treatment of MCF7 breast cancer cells inhibits mitochondrial oxygen-consumption, as well as glycolysis, but induces oxidative stress. Importantly, bedaquiline significantly blocks the propagation and expansion of MCF7-derived CSCs, with an IC-50 of approx. 1-µM, as determined using the mammosphere assay. Similarly, bedaquiline also reduces both the CD44+/CD24low/- CSC and ALDH+ CSC populations, under anchorage-independent growth conditions. In striking contrast, bedaquiline significantly increases oxygen consumption in normal human fibroblasts, consistent with the fact that it is well-tolerated in patients treated for TB infections. As such, future pre-clinical studies and human clinical trials in cancer patients may be warranted. Interestingly, we also highlight that bedaquiline shares certain structural similarities with trans-piceatannol and trans-resveratrol, which are known natural flavonoid inhibitors of the mitochondrial ATP-synthase (complex V) and show anti-aging properties.


Assuntos
Antituberculosos/farmacologia , Proliferação de Células/efeitos dos fármacos , Diarilquinolinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Células MCF-7 , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos
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