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1.
Int J Mol Sci ; 22(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34948016

RESUMO

Glioblastoma (GBM) remains the leading cause of cancer-related deaths with the lowest five-year survival rates among all of the human cancers. Multiple factors contribute to its poor outcome, including intratumor heterogeneity, along with migratory and invasive capacities of tumour cells. Over the last several years Doublecortin (DCX) has been one of the debatable factors influencing GBM cells' migration. To resolve DCX's ambiguous role in GBM cells' migration, we set to analyse the expression patterns of DCX along with Nestin (NES) and Oligodendrocyte lineage transcription factor 2 (OLIG2) in 17 cases of GBM, using immunohistochemistry, followed by an analysis of single-cell RNA-seq data. Our results showed that only a small subset of DCX positive (DCX+) cells was present in the tumour. Moreover, no particular pattern emerged when analysing DCX+ cells relative position to the tumour margin. By looking into single-cell RNA-seq data, the majority of DCX+ cells were classified as non-cancerous, with a small subset of cells that could be regarded as glioma stem cells. In conclusion, our findings support the notion that glioma cells express DCX; however, there is no clear evidence to prove that DCX participates in GBM cell migration.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteína Duplacortina/metabolismo , Perfilação da Expressão Gênica/métodos , Glioblastoma/metabolismo , Nestina/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Neoplasias Encefálicas/genética , Movimento Celular , Proteína Duplacortina/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Heurística , Humanos , Processamento de Imagem Assistida por Computador , Microscopia Confocal , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Nestina/genética , Fator de Transcrição 2 de Oligodendrócitos/genética , Análise de Sequência de RNA , Análise de Célula Única , Análise de Sobrevida
2.
Molecules ; 25(9)2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32353989

RESUMO

Naturally occurring coumarins are bioactive compounds widely used in Asian traditional medicine. They have been shown to inhibit proliferation, induce apoptosis, and/or enhance the cytotoxicity of currently used drugs against a variety of cancer cell types. The aim of our study was to examine the antiproliferative activity of different linear furanocoumarins on human rhabdomyosarcoma, lung, and larynx cancer cell lines, and dissolve their cellular mechanism of action. The coumarins were isolated from fruits of Angelica archangelica L. or Pastinaca sativa L., and separated using high-performance counter-current chromatography (HPCCC). The identity and purity of isolated compounds were confirmed by HPLC-DAD and NMR analyses. Cell viability and toxicity assessments were performed by means of methylthiazolyldiphenyl-tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays, respectively. Induction of apoptosis and cell cycle progression were measured using flow cytometry analysis. qPCR method was applied to detect changes in gene expression. Linear furanocoumarins in a dose-dependent manner inhibited proliferation of cancer cells with diverse activity regarding compounds and cancer cell type specificity. Imperatorin (IMP) exhibited the most potent growth inhibitory effects against human rhabdomyosarcoma and larynx cancer cell lines owing to inhibition of the cell cycle progression connected with specific changes in gene expression, including CDKN1A. As there are no specific chemotherapy treatments dedicated to laryngeal squamous cell carcinoma and rhabdomyosarcoma, and IMP seems to be non-toxic for normal cells, our results could open a new direction in the search for effective anti-cancer agents.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Furocumarinas/farmacologia , Neoplasias Laríngeas/patologia , Rabdomiossarcoma/patologia , Angelica archangelica/química , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Cromatografia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Citometria de Fluxo , Frutas/química , Humanos , L-Lactato Desidrogenase/metabolismo , Neoplasias Laríngeas/tratamento farmacológico , Pastinaca/química , Rabdomiossarcoma/tratamento farmacológico
3.
Immunol Invest ; 47(3): 251-263, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29336620

RESUMO

The objective of this study was to analyze how Staphylococcus epidermidis SCV and WT strains manipulate the PI3K/Akt/mTOR signaling pathway. Six S. epidermidis strains with normal phenotype (WT) and six S. epidermidis strains with SCV phenotype were isolated in parallel from six patients with the prosthetic hip joint infections. THP-1 activated cells were incubated with or without PI3K inhibitor-wortmannin or with mTOR inhibitor-rapamycin. Next, macrophages were exposed to S. epidermidis WT and SCV strains. After 4 h incubation, bacterial survival inside macrophages as well as PI3K-mTOR activation was analyzed. SCV strains of S. epidermidis increased the level of Akt phosphorylation, compared to uninfected macrophages and to their parental WT forms. Wild type variants of S. epidermidis phosphorylated Akt at similar or lower levels as control uninfected cells. Next, the induction of mTOR target, phosphorylated ribosomal protein S6, was measured in bacteria-infected macrophages. The level of phosphorylation was significantly reduced when the cells were exposed to WT strains of S. epidermidis. In contrast, the SCV strains activated S6 protein mostly at a level comparable to the control cells. Rapamycin inhibited mTOR activation as the number of p-S6 positive cells decreased in the tested cases. To conclude, the SCV strains activate the PI3K-Akt signaling pathway in opposite to WT strains. This fact however did not influence the increase in the number of live SCV bacteria as compared to the WT strains. Knowing that the PI3K-Akt pathway is involved in proinflammatory cytokines suppression, SCVs seem to use this pathway to reduce the inflammatory response during the infection.


Assuntos
Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Androstadienos/farmacologia , Linhagem Celular , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Viabilidade Microbiana/imunologia , Fosforilação , Infecções Relacionadas à Prótese , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Infecções Estafilocócicas/imunologia , Wortmanina
4.
J Enzyme Inhib Med Chem ; 31(4): 608-18, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26114307

RESUMO

A series of urea derivatives bearing nitroaryl moiety has been synthesized and assayed for their potential antiproliferative activities. Some of the tested compounds displayed activity in RK33 laryngeal cancer cells and TE671 rhabdomyosarcoma cells while being generally less toxic to healthy HSF human fibroblasts cells. One compound was demonstrated to be a moderate CDK2 inhibitor with IC50 = 14.3 µM. Its structure was solved by an X-ray crystallography and molecular modelling was performed to determine structure-activity relationship. Obtained compounds constitute novel structures and generally demonstrated greater cytotoxicity in comparison to cisplatin. This study offers new structural motifs with potential for further development.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Ureia/química
5.
Neurol Neurochir Pol ; 48(5): 309-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25440008

RESUMO

BACKGROUND AND PURPOSE: To find the relationship between rtPA treatment vs. MMP-9 activity, MMP-3, and TIMP-1 serum levels related to patients' neurological status during acute ischaemic stroke (IS). MATERIAL AND METHODS: 35 IS patients were enrolled. 14 of them underwent thrombolytic therapy with Actylise (rtPA group). The serum samples were obtained at 3 time-points for rtPA group (time-point 0: 1st-4th hour of stroke; time-point 1 - immediately after rtPA administration; time-point 2 - on day 5-7 from stroke onset). Remaining patients had venous blood collection at two time-points: time-point 1 - 5th-10th hour of stroke and time-point 2 - on day 5-7 of stroke. MMP-9 was analyzed with gelatin zymography, MMP-3 and TIMP-1 serum levels were analyzed with ELISA method. NIHSS improvement ratio (IR) was calculated as a difference between NIHSS score at the admission and discharge of patient. RESULTS: The active form of MMP-9 (86kDa) was not observed in any analyzed samples. Total MMP-9 activity was significantly elevated at time-point 1 in rtPA group in comparison with non-rtPA group. MMP-3 serum level significantly decreased during rtPA administration in comparison with non-rtPA group and it was restored at time-point 2. MMP-3 negatively correlated with IR values (p=0.06). CONCLUSIONS: Thrombolysis applied for IS treatment increases MMP-9 activity in serum, however, rtPA does not facilitate the conversion of pro-MMP-9 into the active form. Our results also suggest the involvement of MMP-3 to the biochemical processes occurring during acute phase of IS.


Assuntos
Fibrinolíticos/uso terapêutico , Metaloproteinase 9 da Matriz/sangue , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Isquemia Encefálica/etiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Metaloproteinase 3 da Matriz/sangue , Exame Neurológico , Acidente Vascular Cerebral/complicações , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/sangue
6.
Cells ; 13(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38667336

RESUMO

Treatment-free remission (TFR) is achieved in approximately half of chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitors. The mechanisms responsible for TFR maintenance remain elusive. This study aimed to identify immune markers responsible for the control of residual CML cells early in the TFR (at 3 months), which may be the key to achieving long-term TFR and relapse-free survival (RFS) after discontinuation of imatinib. Our study included 63 CML patients after imatinib discontinuation, in whom comprehensive analysis of changes in the immune system was performed by flow cytometry, and changes in the BCR::ABL1 transcript levels were assessed by RQ-PCR and ddPCR. We demonstrated a significant increase in the percentage of CD8+PD-1+ cells in patients losing TFR. The level of CD8+PD-1+ cells is inversely related to the duration of treatment and incidence of deep molecular response (DMR) before discontinuation. Analysis of the ROC curve showed that the percentage of CD8+PD-1+ cells may be a significant factor in early molecular recurrence. Interestingly, at 3 months of TFR, patients with the e13a2 transcript had a significantly higher proportion of the PD-1-expressing immune cells compared to patients with the e14a2. Our results suggest the important involvement of CD8+PD-1+ cells in the success of TFR and may help in identifying a group of patients who could successfully discontinue imatinib.


Assuntos
Linfócitos T CD8-Positivos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva , Receptor de Morte Celular Programada 1 , Humanos , Mesilato de Imatinib/uso terapêutico , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Idoso , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Adulto Jovem
7.
J Clin Med ; 12(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615173

RESUMO

Triple-negative breast cancers (TNBCs) are histologically heterogenic invasive carcinomas of no specific type that lack distinctive histological characteristics. The prognosis for women with TNBC is poor. Regardless of the applied treatments, recurrences and deaths are observed 3-5 years after the diagnosis. Thus, new diagnostic markers and targets for personalized treatment are needed. The subject of our study-the Kaiso transcription factor has been found to correlate with the invasion and progression of breast cancer. The publicly available TCGA breast cancer cohort containing Illumina HiSeq RNAseq and clinical data was explored in the study. Additionally, Kaiso protein expression was assessed in formalin-fixed and paraffin-embedded tissue archive specimens using the tissue microarray technique. In this retrospective study, Kaiso protein expression (nuclear localization) was compared with several clinical factors in the cohort of 103 patients with TNBC with long follow-up time. In univariate and multivariate analysis, high Kaiso protein but not mRNA expression was correlated with better overall survival and disease-free survival, as well as with premenopausal age. The use of radiotherapy was correlated with better disease-free survival (DFS) and overall survival (OS). However, given the heterogeneity of TNBC and context-dependent molecular diversity of Kaiso signaling in cancer progression, these results must be taken with caution and require further studies.

8.
Cancers (Basel) ; 15(19)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37835383

RESUMO

Estrogen receptor (ER) signaling is a critical regulator of cell proliferation, differentiation, and survival in breast cancer (BC) and other hormone-sensitive cancers. In this review, we explore the mechanism of ER-dependent downstream signaling in BC and the role of estrogens as growth factors necessary for cancer invasion and dissemination. The significance of the clinical implications of ER signaling in BC, including the potential of endocrine therapies that target estrogens' synthesis and ER-dependent signal transmission, such as aromatase inhibitors or selective estrogen receptor modulators, is discussed. As a consequence, the challenges associated with the resistance to these therapies resulting from acquired ER mutations and potential strategies to overcome them are the critical point for the new treatment strategies' development.

9.
Foods ; 11(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36140933

RESUMO

Artisanal cheeses can be sources of Listeria monocytogenes and cause disease in humans. This bacterial pathogen is a species of diverse genotypic and phenotypic characteristics. The aim of the study was to characterize 32 isolates of L. monocytogenes isolated in 2014-2018 from artisanal cheeses. The isolates were characterized using whole genome sequencing and bioinformatics analysis. The artisanal cheese isolates resolved to four molecular groups: 46.9% of them to IIa (1/2a-3a), 31.2% to IVb (4ab-4b-4d-4e), 12.5% to IIc (1/2c-3c), and 9.4% to IIb (1/2b-3b-7). Two evolutionary lineages emerged: lineage II having 59.4% of the isolates and lineage I having 40.6%. The sequence types (ST) totaled 18: ST6 (15.6% of the isolates), ST2, ST20, ST26, and ST199 (each 9.4%), ST7 and ST9 (each 6.3%), and ST1, ST3, ST8, ST16, ST87, ST91, ST121, ST122, ST195, ST217, and ST580 (each 3.1%). There were 15 detected clonal complexes (CC): CC6 (15.6% of isolates), CC9 (12.5%), CC2, CC20, CC26, and CC199 (each 9.4%), CC7 and CC8 (each 6.3%), and CC1, CC3, CC14, CC87, CC121, CC195, and CC217 (each 3.1%). The isolates were varied in their virulence genes and the differences concerned: inl, actA, LIPI-3, ami, gtcA, aut, vip, and lntA.

10.
Anticancer Res ; 41(2): 983-991, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33517305

RESUMO

BACKGROUND/AIM: Tumorigenesis and cancer progression might be driven by abnormal activation of growth factor receptors. Importantly, molecular changes in EGFR-dependent signaling is one of the most common characteristics of brain tumors. PATIENTS AND METHODS: HER1 and EGFRvIII variants in meningiomas and glioblastomas were evaluated at the RNA level. RESULTS: EGFRvIII was found in 18.6% of glioblastomas (GBM), whereas 25% of EGFRvIII positive tumors express wild-type EGFR as well. HER1 was over-expressed in benign meningiomas compared to glioblastomas, whereas HER1 expression in meningiomas differed significantly between sub-types of meningiomas. EGFRvIII and HER1 where positively correlated in glioblastomas. Yet, the patient overall survival did not differ between high- and low-HER1 expressing glioblastomas or between EGFRvIII positive and negative GBMs. CONCLUSION: HER1 may be considered as an independent factor for classification of benign meningiomas. The mRNA levels of HER1 or EGFRvIII should not be used as independent prognostic factors for patients with gliomas.


Assuntos
Neoplasias Encefálicas/cirurgia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Receptores ErbB/genética , Feminino , Marcadores Genéticos , Humanos , Masculino , Neoplasias Meníngeas/genética , Meningioma/genética , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , Regulação para Cima
11.
Cells ; 8(12)2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31847480

RESUMO

Cell plasticity, defined as the ability to undergo phenotypical transformation in a reversible manner, is a physiological process that also exerts important roles in disease progression. Two forms of cellular plasticity are epithelial-mesenchymal transition (EMT) and its inverse process, mesenchymal-epithelial transition (MET). These processes have been correlated to the poor outcome of different types of neoplasias as well as drug resistance development. Since EMT/MET are transitional processes, we generated and validated a reporter cell line. Specifically, a far-red fluorescent protein was knocked-in in-frame with the mesenchymal gene marker VIMENTIN (VIM) in H2170 lung cancer cells. The vimentin reporter cells (VRCs) are a reliable model for studying EMT and MET showing cellular plasticity upon a series of stimulations. These cells are a robust platform to dissect the molecular mechanisms of these processes, and for drug discovery in vitro and in vivo in the future.


Assuntos
Transição Epitelial-Mesenquimal/genética , Engenharia Genética/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Plasticidade Celular/genética , Técnicas de Introdução de Genes/métodos , Células HEK293 , Humanos , Proteínas Luminescentes/genética , Vimentina/genética , Vimentina/metabolismo , Proteína Vermelha Fluorescente
12.
Pharmacol Rep ; 71(3): 528-534, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31015093

RESUMO

BACKGROUND: There is debate regarding whether inhaled sevoflurane or intravenous propofol used during anesthesia achieves the best outcome. Propofol has been shown to affect expression of matrix metalloproteinases (MMPs). MMPs are enzymes that play a role in extracellular matrix remodeling, with activity balance disturbances during surgery. The goal of this study was to compare MMP-2/9 concentrations, activity, and tissue inhibitors of metalloproteinases (TIMPs) 1/2 concentrations in blood of who had undergone 2 types of anesthesia: based on volatile sevoflurane and intravenous propofol during non-oncological, non-vascular surgery. METHODS: 39 patients were enrolled into analysis, 20 anesthetized with total intravenous anesthesia with propofol (P), 19 with volatile induction/maintenance of anesthesia with sevoflurane (S). Plasma samples collected before and 24 h after surgery were analyzed for MMP-2/9, and TIMP-1/2 concentrations using ELISAs. Additionally, MMP-2/9 activities were assessed by gelatin zymography. RESULTS: Study revealed increased MMP-9 concentration (ELISA) (P:p = 0.011; S:p = 0.001) and activity (zymography) (P:p = 0.004; S:p = 0.008) in both groups 24 h after surgery. We noticed decreased (both groups) MMP-2 concentration (P:p = 0.044; S:p = 0.027) with MMP-2 activity increase (P:p = 0.002; S:p = 0.006) 24 h after surgery. We observed decreased TIMP-1 plasma concentrations (P:p = 0.002; S:p = 0.000) 24 h after procedures, while TIMP-2 plasma levels remain unchanged (P:p = 0.097; S:p = 0.172). There were no differences between concentration and activity of MMPs and TIMPs in regard to anesthetic used. Meperidine administration correlated with lower MMP-9 activity (R=-0.430; p = 0.006). CONCLUSIONS: Concluding, neither sevoflurane nor propofol used as anesthetics modulate MMP-2 and MMP-9 concentrations and activities during non-oncological, non-vascular elective surgery. Meperidine seems to decrease MMP-9 activity.


Assuntos
Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Propofol/uso terapêutico , Sevoflurano/uso terapêutico , Anestesia Geral/métodos , Anestésicos Intravenosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-30619090

RESUMO

Follicle stimulating hormone (FSH) plays a key role in human reproduction through, among others, induction of spermatogenesis in men and production of estrogen in women. The function FSH is performed upon binding to its cognate receptor-follicle-stimulating hormone receptor (FSHR) expressed on the surface of target cells (granulosa and Sertoli cells). FSHR belongs to the family of G protein-coupled receptors (GPCRs), a family of receptors distinguished by the presence of various signaling pathway activation as well as formation of cross-talking aggregates. Until recently, it was claimed that the FSHR occurred naturally as a monomer, however, the crystal structure as well as experimental evidence have shown that FSHR both self-associates and forms heterodimers with the luteinizing hormone/chorionic gonadotropin receptor-LHCGR. The tremendous gain of knowledge is also visible on the subject of receptor activation. It was once thought that activation occurs only as a result of ligand binding to a particular receptor, however there is mounting evidence of trans-activation as well as biased signaling between GPCRs. Herein, we describe the mechanisms of aforementioned phenomena as well as briefly describe important experiments that contributed to their better understanding.

14.
Expert Opin Drug Discov ; 13(5): 459-472, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29447015

RESUMO

INTRODUCTION: The discovery and domestication of biomolecules that respond to light has taken a light of its own, providing new molecular tools with incredible spatio-temporal resolution to manipulate cellular behavior. Areas covered: The authors herein analyze the current optogenetic tools in light of their current, and potential, uses in cancer drug discovery, biosafety and cancer biology. Expert opinion: The pipeline from drug discovery to the clinic is plagued with drawbacks, where most drugs fail in either efficacy or safety. These issues require the redesign of the pipeline and the development of more controllable/personalized therapies. Light is, aside from inexpensive, almost harmless if used appropriately, can be directed to single cells or organs with controllable penetration, and comes in a variety of wavelengths. Light-responsive systems can activate, inhibit or compensate cell signaling pathways or specific cellular events, allowing the specific control of the genome and epigenome, and modulate cell fate and transformation. These synthetic molecular tools have the potential to revolutionize drug discovery and cancer research.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Optogenética/métodos , Animais , Antineoplásicos/administração & dosagem , Descoberta de Drogas/métodos , Humanos , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão/métodos , Transdução de Sinais
15.
Front Chem ; 5: 12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28344971

RESUMO

In biological systems, the formation of molecular complexes is the currency for all cellular processes. Traditionally, functional experimentation was targeted to single molecular players in order to understand its effects in a cell or animal phenotype. In the last few years, we have been experiencing rapid progress in the development of ground-breaking molecular biology tools that affect the metabolic, structural, morphological, and (epi)genetic instructions of cells by chemical, optical (optogenetic) and mechanical inputs. Such precise dissection of cellular processes is not only essential for a better understanding of biological systems, but will also allow us to better diagnose and fix common dysfunctions. Here, we present several of these emerging and innovative techniques by providing the reader with elegant examples on how these tools have been implemented in cells, and, in some cases, organisms, to unravel molecular processes in minute detail. We also discuss their advantages and disadvantages with particular focus on their translation to multicellular organisms for in vivo spatiotemporal regulation. We envision that further developments of these tools will not only help solve the processes of life, but will give rise to novel clinical and industrial applications.

16.
Oncotarget ; 8(56): 95163-95175, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29221119

RESUMO

Mutations of the nucleophosmin-1 (NPM1) gene in cytogenetically normal (CN) acute myeloid leukemia (AML) identify a group of patients with more favorable prognosis. NPM1 encodes three main alternatively spliced isoforms R1(B23.1), R2(B23.2), and R3(B23.3). The expression of splice variants R1, R2 and R3 were higher in AML patients compared to normal cells of healthy volunteers (HVs), although RNA-seq analysis revealed enhanced R2 expression also in less differentiated cells of HVs as well as in AML cells. The variant R2, which lacks exons 11 and 12 coding for the nucleolar localization domain, might behave similar to the mutant form of NPM1 (NPM1mut). In accordance, in CN-AML high R2 expression was associated with favorable impact on outcome. Moreover, functional studies showed nucleolar localization of the eGFP-NPM1 wildtype and cytoplasmic localization of the eGFP-NPM1 mut protein. While the eGFP-NPM1 R2 splice variant localized predominantly in the nucleoplasm, we also could detect cytoplasmic expression for the R2 variant. These results support a unique biological consequence of R2 overexpression and in part explain our clinical observation, where that high R2 variant expression was associated with a better prognosis in CN-AML patients.

17.
Sci Rep ; 6: 19121, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26750263

RESUMO

Mutagenesis is an important tool to study gene regulation, model disease-causing mutations and for functional characterisation of proteins. Most of the current methods for mutagenesis involve multiple step procedures. One of the most accurate methods for genetically altering DNA is recombineering, which uses bacteria expressing viral recombination proteins. Recently, the use of in vitro seamless assembly systems using purified enzymes for multiple-fragment cloning as well as mutagenesis is gaining ground. Although these in vitro isothermal reactions are useful when cloning multiple fragments, for site-directed mutagenesis it is unnecessary. Moreover, the use of purified enzymes in vitro is not only expensive but also more inaccurate than the high-fidelity recombination inside bacteria. Here we present a single-step method, named REPLACR-mutagenesis (Recombineering of Ends of linearised PLAsmids after PCR), for creating mutations (deletions, substitutions and additions) in plasmids by in vivo recombineering. REPLACR-mutagenesis only involves transformation of PCR products in bacteria expressing Red/ET recombineering proteins. Modifications in a variety of plasmids up to bacterial artificial chromosomes (BACs; 144 kb deletion) have been achieved by this method. The presented method is more robust, involves fewer steps and is cost-efficient.


Assuntos
Engenharia Genética , Mutagênese Sítio-Dirigida , Plasmídeos , Reação em Cadeia da Polimerase , Recombinação Genética , Cromossomos Artificiais Bacterianos , Clonagem Molecular , Mutação
18.
J Endocrinol ; 231(3): 197-207, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27656125

RESUMO

Glycoprotein hormones are complex hormonally active macromolecules. Luteinizing hormone (LH) is essential for the postnatal development and maturation of the male gonad. Inactivating Luteinizing hormone beta (LHB) gene mutations are exceptionally rare and lead to hypogonadism that is particularly severe in males. We describe a family with selective LH deficiency and hypogonadism in two brothers. DNA sequencing of LHB was performed and the effects of genetic variants on hormone function and secretion were characterized by mutagenesis studies, confocal microscopy and functional assays. A 20-year-old male from a consanguineous family had pubertal delay, hypogonadism and undetectable LH. A homozygous c.118_120del (p.Lys40del) mutation was identified in the patient and his brother, who subsequently had the same phenotype. Treatment with hCG led to pubertal development, increased circulating testosterone and spermatogenesis. Experiments in HeLa cells revealed that the mutant LH is retained intracellularly and showed diffuse cytoplasmic distribution. The mutated LHB heterodimerizes with the common alpha-subunit and can activate its receptor. Deletion of flanking glutamic acid residues at positions 39 and 41 impair LH to a similar extent as deletion of Lys40. This region is functionally important across all heterodimeric glycoprotein hormones, because deletion of the corresponding residues in hCG, follicle-stimulating hormone and thyroid-stimulating hormone beta-subunits also led to intracellular hormone retention. This novel LHB mutation results in hypogonadism due to intracellular sequestration of the hormone and reveals a discrete region in the protein that is crucial for normal secretion of all human glycoprotein hormones.


Assuntos
Eunuquismo/genética , Hormônio Luteinizante Subunidade beta/genética , Proteínas Mutantes/genética , Adolescente , Sequência de Aminoácidos , Transporte Biológico Ativo , Gonadotropina Coriônica/uso terapêutico , Consanguinidade , Eunuquismo/tratamento farmacológico , Eunuquismo/metabolismo , Feminino , Mutação em Linhagem Germinativa , Células HEK293 , Células HeLa , Homozigoto , Humanos , Hormônio Luteinizante Subunidade beta/química , Hormônio Luteinizante Subunidade beta/deficiência , Masculino , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Linhagem , Estrutura Quaternária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Transdução de Sinais , Adulto Jovem
19.
Neurol Res ; 37(1): 9-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24963695

RESUMO

One of the most significant side effects during recombinant tissue plasminogen activator (rtPA) for acute stroke treatment is intracranial bleeding. Gelatinases [matrix metalloproteinase (MMP)-2 and MMP-9] are one of the agents involved in the blood-brain barrier destruction resulting in secondary bleeding into the ischemic area during stroke. Previous papers revealed that patients with high baseline MMP-9 serum level have higher risk of intracranial bleeding after thrombolytic therapy. Our objective was to evaluate rtPA influence on serum MMP-2 and MMP-9 activities in vitro. Nine sera obtained from healthy donors were applied for experiment. The commercially available rtPA (Actylise) were diluted with included solvent and additionally with phosphate-buffered saline (PBS) to get concentrations: 2, 4, 8, and 16 µg/ml. Next, 100 µl of serum was mixed with equal proportion with different concentrations of rtPA to obtain final rtPA concentrations: 1, 2, 4, and 8 µg/ml. The sera together with rtPA were incubated for 1 or 2 hours at 37 °C. The activity of gelatinases was estimated with zymography. The activities of MMP-9 (92 kDa) and MMP-2 (72 kDa) were increased by incubation with rtPA in a dose-dependent manner. Simultaneously, the activity of band at 200 kDa (MMP-9/MMP-9 homodimer) was decreased. The activity of gelatinases incubated for 2 hours was elevated in comparison with 1-hour incubation; however, the increase was observed even for sample without rtPA. In conclusion, this study showed that rtPA can increase the biological activity of MMP-2 and MMP-9 on posttranslational level.


Assuntos
Fibrinolíticos/farmacologia , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Proteínas Recombinantes/farmacologia , Ativador de Plasminogênio Tecidual/farmacologia , Relação Dose-Resposta a Droga , Humanos
20.
Biomed Res Int ; 2015: 584189, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25866796

RESUMO

Numerous plant-derived substances, and their derivatives, are effective antitumour and chemopreventive agents. Yet, there are also a plethora of tumour types that do not respond, or become resistant, to these natural substances. This requires the discovery of new active compounds. Betulin (BE) is a pentacyclic triterpene and secondary metabolite of plants abundantly found in the outer bark of the birch tree Betulaceae sp. BE displays a broad spectrum of biological and pharmacological properties, among which the anticancer and chemopreventive activity attract most of the attention. In this vein, BE and its natural and synthetic derivatives act specifically on cancer cells with low cytotoxicity towards normal cells. Although the antineoplastic mechanism of action of BE is not well understood yet, several interesting aspects of BE's interactions are coming to light. This review will summarize the anticancer and chemopreventive potential of BE in vitro and in vivo by carefully dissecting and comparing the doses and tumour lines used in previous studies, as well as focusing on mechanisms underlying its activity at cellular and molecular level, and discuss future prospects.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias/tratamento farmacológico , Triterpenos/uso terapêutico , Animais , Linhagem Celular Tumoral , Humanos , Neoplasias/metabolismo
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