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1.
BMC Cancer ; 22(1): 1298, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503417

RESUMO

BACKGROUND: Metaplastic breast cancer (MpBC) is an aggressive subtype of breast carcinoma that is often resistant to conventional chemotherapy. Therefore, novel treatment strategies are urgently needed. Immune check point inhibitors have shown activity in programmed death-ligand 1 (PD-L1) - positive metastatic triple negative breast carcinoma (TNBC), which raises the possibility that immunotherapy may also be effective in MpBC as most of the MpBCs are triple negative. The aim of the present study was to assess genomic instability and immunogenicity in tumor specimens of patients with MpBC. METHODS: A total of 76 patients diagnosed with MpBC over a 15-year period were included in the study. We performed immunohistochemical analyses for tumor cell PD-L1, immune cell PD-L1 and p53 on tissue microarrays (TMAs), analyzed stromal and intratumoral tumor infiltrating lymphocytes (TILs) from hematoxylin and eosin-stained (H&E) slides and scored gamma-H2AX (γH2AX) and phosphorylated-RPA2 (pRPA2) from whole tissue sections. We correlated marker expression with clinicopathologic features and clinical outcome. RESULTS: All tumors expressed γH2AX and pRPA2 with median expressions of 43% and 44%. P53- (68%), tumor cell PD-L1- (59%) and immune cell PD-L1-positivity (62%) were common in MpBCs. Median stromal TIL and intratumoral TIL counts were 5% and 0. The spindle and squamous cell carcinomas expressed the highest levels of PD-L1 and TILs, and carcinoma with mesenchymal differentiation the lowest. CONCLUSIONS: MpBC appears to be an immunogenic cancer with high genomic instability and frequent PD-L1-positivity, implying that check point inhibitors might be effective in MpBC. Expression levels of PD-L1 and TILs varied across different histologic subtypes, suggesting that immunotherapy might be less effective in carcinoma with mesenchymal differentiation.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Mama Triplo Negativas , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linfócitos do Interstício Tumoral , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Prognóstico , Biomarcadores Tumorais/metabolismo , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia
2.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34884838

RESUMO

Alterations to amino acid residues G4946 and I4790, associated with resistance to diamide insecticides, suggests a location of diamide interaction within the pVSD voltage sensor-like domain of the insect ryanodine receptor (RyR). To further delineate the interaction site(s), targeted alterations were made within the same pVSD region on the diamondback moth (Plutella xylostella) RyR channel. The editing of five amino acid positions to match those found in the diamide insensitive skeletal RyR1 of humans (hRyR1) in order to generate a human-Plutella chimeric construct showed that these alterations strongly reduce diamide efficacy when introduced in combination but cause only minor reductions when introduced individually. It is concluded that the sites of diamide interaction on insect RyRs lie proximal to the voltage sensor-like domain of the RyR and that the main site of interaction is at residues K4700, Y4701, I4790 and S4919 in the S1 to S4 transmembrane domains.


Assuntos
Diamida/química , Proteínas de Insetos/química , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Animais , Sítios de Ligação , Cafeína/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Diamida/metabolismo , Diamida/farmacologia , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/química , Inseticidas/metabolismo , Inseticidas/farmacologia , Mariposas/metabolismo , Mutagênese Sítio-Dirigida , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ortoaminobenzoatos/química , ortoaminobenzoatos/metabolismo , ortoaminobenzoatos/farmacologia
3.
Acta Neurochir (Wien) ; 162(4): 763-776, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32025806

RESUMO

BACKGROUND: Chronic subdural haematoma (CSDH) is a pathology that is frequently encountered by neurosurgeons. Nevertheless, there is a lack of guidelines based on solid evidence. There has been a recent and considerable increase in the interest on management and outcomes for CSDH. Therefore, we systematically reviewed all currently running randomised controlled trials (RCTs) in chronic subdural haematoma to understand the areas under investigation and plan future collaborative trials. METHODS: Clinical trials databases (Cochrane Controlled Register of Trials, WHO ICTRP and clinical trials.gov) were searched for trials relevant to chronic subdural haematoma. It was then established which trials were currently running and fulfilled robust research methodology for a RCT. RESULTS: There are 26 currently running RCTs in CSDH, with the most common topics covering application of steroids (7), surgical techniques (5) and tranexamic acid (5). Further to this, there are trials running on other pharmacological agents (4), middle meningeal artery (MMA) embolisation (2) and peri-operative management (3). CONCLUSIONS: Pharmacological agents are a particular focus of CSDH management currently, and a wealth of studies on steroids will hopefully lead to more harmonised, evidence-based practice regarding this in the near future. Surgical techniques and new procedures such as MMA embolisation are also important focuses for improving patient outcomes. There is an on-going need for future RCTs and evidence-based guidelines in CSDH, particularly including low- and middle-income countries, and it is hoped that the establishment of the iCORIC (International COllaborative Research Initiative on Chronic Subdural Haematoma) will help address this.


Assuntos
Hematoma Subdural Crônico/cirurgia , Procedimentos Neurocirúrgicos , Humanos , Cooperação Internacional , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Ann Oncol ; 29(3): 563-572, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29324969

RESUMO

The apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) mutational signature has only recently been detected in a multitude of cancers through next-generation sequencing. In contrast, APOBEC has been a focus of virology research for over a decade. Many lessons learnt regarding APOBEC within virology are likely to be applicable to cancer. In this review, we explore the parallels between the role of APOBEC enzymes in HIV and cancer evolution. We discuss data supporting the role of APOBEC mutagenesis in creating HIV genome heterogeneity, drug resistance, and immune escape variants. We hypothesize similar functions of APOBEC will also hold true in cancer.


Assuntos
Desaminases APOBEC/fisiologia , Resistência a Medicamentos/fisiologia , Mutagênese/fisiologia , Neoplasias/enzimologia , Neoplasias/genética , Animais , HIV/genética , Infecções por HIV/enzimologia , Humanos , Tolerância Imunológica/fisiologia
5.
Acta Neurol Scand ; 136(5): 516-520, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28382656

RESUMO

OBJECTIVE: Chronic subdural hematoma (cSDH) is a prevalent condition often seen in the elderly, with surgery being the treatment of choice when symptomatic. So far, few have explored the surgical outcomes in patients 90 years or older. The aim of this study was to investigate outcome after cSDH surgery in nonagenarians (≥90 y/o group) compared to younger adult patients (<90 y/o group). MATERIALS: In a Scandinavian population-based cohort we conducted a retrospective review of 1,254 patients undergoing primary burr-hole procedures for cSDH between January 1, 2005 and December 31, 2010 at three neurosurgical centers. In a comparative analysis, the primary end-point was difference in hematoma recurrence rates between the ≥90 y/o and <90 y/o groups. The secondary end-points were differences in perioperative morbidity and mortality between groups. RESULTS: 75 patients were 90 years or older. There was no significant difference in recurrences resulting in reoperation between the age groups (10.7% vs 13.6%, P=.47). There was also no significant difference in overall complication rate (4.1% vs 8.1%, P=.21) or severe complications (1.4% vs 2.0%, P=.68). There were three (4.0%) perioperative deaths within 30 days in the ≥90 y/o group and 40 (3.4%) in the <90 y/o group (P=.78). CONCLUSION: Patients 90 years or older had similar rates of recurrence, perioperative morbidity and perioperative mortality as compared to younger patients. Age alone should not be a contraindication for surgery in patients with cSDH.


Assuntos
Hematoma Subdural Crônico/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Idoso Fragilizado , Humanos , Masculino , Prevalência , Recidiva
6.
Angew Chem Int Ed Engl ; 55(33): 9748-52, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27377237

RESUMO

In this work, the selective electrocatalytic reduction of carbon dioxide to carbon monoxide on oxide-derived silver electrocatalysts is presented. By a simple synthesis technique, the overall high faradaic efficiency for CO production on the oxide-derived Ag was shifted by more than 400 mV towards a lower overpotential compared to that of untreated Ag. Notably, the Ag resulting from Ag oxide is capable of electrochemically reducing CO2 to CO with approximately 80 % catalytic selectivity at a moderate overpotential of 0.49 V, which is much higher than that (ca. 4 %) of untreated Ag under identical conditions. Electrokinetic studies show that the improved catalytic activity is ascribed to the enhanced stabilization of COOH(.) intermediate. Furthermore, highly nanostructured Ag is likely able to create a high local pH near the catalyst surface, which may also facilitate the catalytic activity for the reduction of CO2 with suppressed H2 evolution.

7.
J Am Chem Soc ; 137(48): 15112-21, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26544169

RESUMO

Ni-based oxygen evolution catalysts (OECs) are cost-effective and very active materials that can be potentially used for efficient solar-to-fuel conversion process toward sustainable energy generation. We present a systematic spectroelectrochemical characterization of two Fe-containing Ni-based OECs, namely nickel borate (Ni(Fe)-B(i)) and nickel oxyhydroxide (Ni(Fe)OOH). Our Raman and X-ray absorption spectroscopy results show that both OECs are chemically similar, and that the borate anions do not play an apparent role in the catalytic process at pH 13. Furthermore, we show spectroscopic evidence for the generation of negatively charged sites in both OECs (NiOO(-)), which can be described as adsorbed "active oxygen". Our data conclusively links the OER activity of the Ni-based OECs with the generation of those sites on the surface of the OECs. The OER activity of both OECs is strongly pH dependent, which can be attributed to a deprotonation process of the Ni-based OECs, leading to the formation of the negatively charged surface sites that act as OER precursors. This work emphasizes the relevance of the electrolyte effect to obtain catalytically active phases in Ni-based OECs, in addition to the key role of the Fe impurities. This effect should be carefully considered in the development of Ni-based compounds meant to catalyze the OER at moderate pHs. Complementarily, UV-vis spectroscopy measurements show strong darkening of those catalysts in the catalytically active state. This coloration effect is directly related to the oxidation of nickel and can be an important factor limiting the efficiency of solar-driven devices utilizing Ni-based OECs.

8.
Brain Spine ; 4: 102822, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38831935

RESUMO

Introduction: Technical advances and the increasing role of interdisciplinary decision-making may warrant formal definitions of expertise in surgical neuro-oncology. Research question: The EANS Neuro-oncology Section felt that a survey detailing the European neurosurgical perspective on the concept of expertise in surgical neuro-oncology might be helpful. Material and methods: The EANS Neuro-oncology Section panel developed an online survey asking questions regarding criteria for expertise in neuro-oncological surgery and sent it to all individual EANS members. Results: Our questionnaire was completed by 251 respondents (consultants: 80.1%) from 42 countries. 67.7% would accept a lifetime caseload of >200 cases and 86.7% an annual caseload of >50 as evidence of neuro-oncological surgical expertise. A majority felt that surgeons who do not treat children (56.2%), do not have experience with spinal fusion (78.1%) or peripheral nerve tumors (71.7%) may still be considered experts. Majorities believed that expertise requires the use of skull-base approaches (85.8%), intraoperative monitoring (83.4%), awake craniotomies (77.3%), and neuro-endoscopy (75.5%) as well as continuing education of at least 1/year (100.0%), a research background (80.0%) and teaching activities (78.7%), and formal interdisciplinary collaborations (e.g., tumor board: 93.0%). Academic vs. non-academic affiliation, career position, years of neurosurgical experience, country of practice, and primary clinical interest had a minor influence on the respondents' opinions. Discussion and conclusion: Opinions among neurosurgeons regarding the characteristics and features of expertise in neuro-oncology vary surprisingly little. Large majorities favoring certain thresholds and qualitative criteria suggest a consensus definition might be possible.

9.
Ann Oncol ; 24(11): 2780-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23897704

RESUMO

BACKGROUND: Defective DNA repair is central to the progression and treatment of breast cancer. Immunohistochemically detected DNA repair markers may be good candidates for novel prognostic and predictive factors that could guide the selection of individualized treatment strategies. PATIENTS AND METHODS: We have analyzed nuclear immunohistochemical staining of BRCA1, FANCD2, RAD51, XPF, and PAR in relation to clinicopathological and survival data among 1240 paraffin-embedded breast tumors, and additional gene expression microarray data from 76 tumors. The antioxidant enzyme NQO1 was analyzed as a potential modifier of prognostic DNA repair markers. RESULTS: RAD51 [hazard ratio (HR) 0.81, 95% confidence interval (CI) 0.70-0.94, P = 0.0050] and FANCD2 expression (HR 1.50, 95% CI 1.28-1.76, P = 1.50 × 10(-7)) were associated with breast cancer survival. High FANCD2 expression correlated with markers of adverse prognosis but remained independently prognostic in multivariate analysis (HR 1.27, 95% CI 1.08-1.49, P = 0.0043). The FANCD2-associated survival effect was most pronounced in hormone receptor positive, HER2-negative tumors, and in tumors with above-median NQO1 expression. In the NQO1-high subset, patients belonging to the highest quartile of FANCD2 immunohistochemical scores had a threefold increased risk of metastasis or death (HR 3.10, 95% CI 1.96-4.92). Global gene expression analysis indicated that FANCD protein overabundance is associated with the upregulation of proliferation-related genes and a downregulated nucleotide excision repair pathway. CONCLUSION: FANCD2 immunohistochemistry is a sensitive, independent prognostic factor in breast cancer, particularly when standard markers indicate relatively favorable prognosis. Taken together, our results suggest that the prognostic effect is linked to proliferation, DNA damage, and oxidative stress; simultaneous detection of FANCD2 and NQO1 provides additional prognostic value.


Assuntos
Neoplasias da Mama/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/biossíntese , NAD(P)H Desidrogenase (Quinona)/biossíntese , Prognóstico , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Reparo do DNA/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , NAD(P)H Desidrogenase (Quinona)/genética , Receptor ErbB-2/genética
10.
Breast Cancer Res Treat ; 129(3): 703-16, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21080063

RESUMO

Clonality of multicentric breast cancer has traditionally been difficult to assess. We aimed to assess this using analysis of TP53 status (expression and mutation status). These results were then incorporated into an analysis of prognostic factors in multicentric tumours in a 10-year follow up study. Clonal status of multicentric breast cancer foci (n = 88 foci) was determined by immunohistochemical and molecular studies of TP53 in a total of 40 patients. Prognostic factors from these patients were also compared with 80 age- and stage-matched controls with unicentric breast cancer from the Royal Marsden NHS Foundation Trust Breast Cancer Database. Our results indicate that multicentric breast cancer foci were polyclonal within an individual patient in at least 10 patients (25%) with respect to immunohistochemical staining and in four patients (10%) with respect to abnormal band shifts on single strand conformational polymorphism (SSCP) molecular analysis. No individual variable was predictive of multicentric or unicentric disease. However, there was a worse overall survival in the multicentric breast cancer patients in whom at least two cancer foci stained positively on TP53 immunohistochemistry compared with the matched control group (P = 0.04). In conclusion, these results suggest that a proportion of multicentric breast cancer foci are polyclonal with respect to TP53 status and that TP53 over-expression predicts for a poorer prognosis in multicentric breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Prognóstico , Proteína Supressora de Tumor p53/metabolismo
11.
Curr Opin Cell Biol ; 13(6): 738-47, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11698191

RESUMO

The ability to preserve genomic integrity is a fundamental feature of life. Recent findings regarding the molecular basis of the cell-cycle checkpoint responses of mammalian cells to genotoxic stress have converged into a two-wave concept of the G1 checkpoint, and shed light on the so-far elusive intra-S-phase checkpoint. Rapidly operating cascades that target the Cdc25A phosphatase appear central in both the initiation wave of the G1 checkpoint (preceding the p53-mediated maintenance wave) and the transient intra-S-phase response. Multiple links between defects in the G1/S checkpoints, genomic instability and oncogenesis are emerging, as are new challenges and hopes raised by this knowledge.


Assuntos
Dano ao DNA , Fase G1 , Fase S , Animais , Previsões , Modelos Biológicos , Neoplasias/genética , Proteínas Quinases/fisiologia , Fatores de Transcrição/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Fosfatases cdc25/fisiologia
12.
Curr Opin Cell Biol ; 8(6): 805-14, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8939678

RESUMO

The emerging role of the retinoblastoma protein (pRb) as a major controller of the restriction point has been supported by recent discoveries, including pRb's ability to repress gene transcription by all three RNA polymerases, which suggests a link between DNA replication and cell growth. Convergent genetic and biochemical data provide new insights into the molecular events that are upstream of, at, and downstream of pRb phosphorylation, which is regulated by G1-phase cyclins and cyclin-dependent kinases (Cdks) and their inhibitors (CKIs). Major advances have also been made in our understanding of a key role of the pathway involving cyclin D, Cdks, CKIs, pRb and E2F both in commitment to traversing the cell cycle and in restraining oncogenesis.


Assuntos
Ciclo Celular/fisiologia , Células/citologia , Proteína do Retinoblastoma/fisiologia , Divisão Celular/fisiologia , Células/química
13.
Nat Cell Biol ; 1(2): 88-93, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10559879

RESUMO

Centrosome duplication is a key requirement for bipolar spindle formation and correct segregation of chromosomes during cell division. In a manner highly reminiscent of DNA replication, the centrosome must be duplicated once, and only once, in each cell cycle. How centrosome duplication is regulated and coordinated with other cell-cycle functions remains poorly understood. Here, we have established a centrosome duplication assay using mammalian somatic cells. We show that centrosome duplication requires the activation of E2F transcription factors and Cdk2-cyclin A activity.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Proteínas de Transporte , Ciclo Celular/fisiologia , Centrossomo/fisiologia , Centrossomo/ultraestrutura , Ciclina A/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Animais , Células CHO , Proteínas de Ciclo Celular/metabolismo , Cricetinae , Quinase 2 Dependente de Ciclina , Fatores de Transcrição E2F , Mamíferos , Proteínas Recombinantes/metabolismo , Proteína 1 de Ligação ao Retinoblastoma , Transfecção
14.
Nat Cell Biol ; 3(4): 392-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283613

RESUMO

Deregulated expression of c-myc can induce cell proliferation in established cell lines and in primary mouse embryonic fibroblasts (MEFs), through a combination of both transcriptional activation and repression by Myc. Here we show that a Myc-associated transcription factor, Miz-1, arrests cells in G1 phase and inhibits cyclin D-associated kinase activity. Miz-1 upregulates expression of the cyclin-dependent kinases (CDK) inhibitor p15INK4b by binding to the initiator element of the p15INK4b promoter. Myc and Max form a complex with Miz-1 at the p15 initiator and inhibit transcriptional activation by Miz-1. Expression of Myc in primary cells inhibits the accumulation of p15INK4b that is associated with cellular senescence; conversely, deletion of c-myc in an established cell line activates p15INK4b expression. Alleles of c-myc that are unable to bind to Miz-1 fail to inhibit accumulation of p15INK4b messenger RNA in primary cells and are, as a consequence, deficient in immortalization.


Assuntos
Proteínas de Transporte/biossíntese , Proteínas de Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor , Dedos de Zinco , Células 3T3 , Animais , Inibidor de Quinase Dependente de Ciclina p15 , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Células HeLa , Humanos , Fatores de Transcrição Kruppel-Like , Camundongos , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/genética
15.
Int J Androl ; 34(4 Pt 2): e103-13, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20695923

RESUMO

Heterochromatinization has been implicated in fundamental biological and pathological processes including differentiation, senescence, ageing and tumourigenesis; however, little is known about its regulation and roles in human cells and tissues in vivo. Here, we show distinct cell-type- and cancer-stage-associated patterns of key heterochromatin marks: histone H3 trimethylated at lysine 9 (H3K9me3) and heterochromatic adaptor proteins HP1α and HP1γ, compared with the γH2AX marker of endogenously activated DNA damage response (DDR) and proliferation markers in normal human foetal (n=4) and adult (n=29) testes, pre-invasive carcinoma in situ (CIS; n=26) lesions and a series of overt germ cell tumours, including seminomas (n=26), embryonal carcinomas (n=18) and teratomas (n=11). Among striking findings were high levels of HP1γ in foetal gonocytes, CIS and seminomas; enhanced multimarker heterochromatinization without DDR activation in CIS; and enhanced HP1α in teratoma structures with epithelial and neuronal differentiation. Differential expression of the three heterochromatin markers suggests their partly non-overlapping roles, and separation of heterochromatinization from DDR activation highlights distinct responses of germ cells vs. somatic tissues in early tumourigenesis. Conceptually interesting findings were that subsets of human cells in vivo proliferate despite enhanced heterochromatinization, and that cells can strongly express even multiple heterochromatin features in the absence of functional retinoblastoma protein and without DDR activation. Overall, these results provide novel insights into cell-related and tumour-related diversity of heterochromatin in human tissues in vivo, relevant for andrology and intrinsic anti-tumour defence roles attributed to activated DDR and cellular senescence.


Assuntos
Proteínas Cromossômicas não Histona/biossíntese , Histonas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/patologia , Testículo/embriologia , Anticorpos Monoclonais , Linhagem Celular , Senescência Celular/genética , Homólogo 5 da Proteína Cromobox , Dano ao DNA , Reparo do DNA , Imunofluorescência , Heterocromatina/metabolismo , Histonas/biossíntese , Histonas/genética , Histonas/imunologia , Humanos , Immunoblotting , Masculino , Metilação , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Testículo/metabolismo
16.
Nat Med ; 3(3): 313-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9055859

RESUMO

Repression of cell cycle progression by tumor suppressors might provide a means for tumor therapy. Here we demonstrate that ectopic overexpression of the p16INK4/CDKN2 tumor suppressor from an adenovirus vector in various cell lines results in block of cell division and, subsequently, in a gradual reduction of the levels of the product of retinoblastoma susceptibility gene, pRb. Overexpression of p53 and p16INK4/CDKN2, but not p53 on its own, induces apoptotic death only in tumor cells. Simultaneous adenoviral transfer of p16 and p53 genes leads to inhibition of tumor growth in nude mice. These results suggest that combined delivery of two cooperating genes like p16 and p53 could be the basis for the development of a new strategy for cancer gene therapy.


Assuntos
Apoptose/genética , Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Genes Supressores de Tumor , Proteína Supressora de Tumor p53/genética , Adenoviridae , Animais , Inibidor p16 de Quinase Dependente de Ciclina , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Camundongos , Células Tumorais Cultivadas
17.
Acta Neurochir Suppl ; 111: 409-13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21725792

RESUMO

Intraventricular hemorrhage (IVH) subsequent to intracerebral hemorrhage (ICH) or subarachnoid hemorrhage (SAH) is associated with high mortality and morbidity. The use of fibrinolytic agents to treat this condition has previously been reported in small clinical trials with limited numbers of patients. Variability regarding inclusion criteria, method of administration and outcome have made it difficult to draw firm conclusions regarding the efficacy of antifibrinolytic therapy. Nine patients with CT-diagnosed IVH were treated with Alteplase intrathecally for 3 to 5 days according to the CT-verified clearance of IVH. After the treatment period, a repeat CT scan was performed to evaluate treatment effect.In this safety study, we achieved rapid removal of IVH compared to retrospective controls, without incidents of re-bleeding, with only 33% permanent shunt placements and a neurological outcome of GOS of 4-5 in 44% of the patients. Based on the above results, the treatment protocol was considered safe and highly effective. A prospective randomized national multicenter trial has been initiated in order to evaluate the efficacy of this novel method also in terms of outcome and shunt dependency.


Assuntos
Fibrinolíticos/uso terapêutico , Hematoma/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/cirurgia , Feminino , Escala de Coma de Glasgow , Hematoma/diagnóstico , Hematoma/etiologia , Hematoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/cirurgia , Sucção/métodos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
18.
J Exp Med ; 189(11): 1685-90, 1999 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-10359571

RESUMO

B-1 lymphocytes represent a distinct B cell subset with characteristic features that include self-renewing capacity and unusual mitogenic responses. B-1 cells differ from conventional B cells in terms of the consequences of phorbol ester treatment: B-1 cells rapidly enter S phase in response to phorbol ester alone, whereas B-2 cells require a calcium ionophore in addition to phorbol ester to trigger cell cycle progression. To address the mechanism underlying the varied proliferative responses of B-1 and B-2 cells, we evaluated the expression and activity of the G1 cell cycle regulator, cyclin D2, and its associated cyclin-dependent kinases (Cdks). Cyclin D2 expression was upregulated rapidly, within 2-4 h, in phorbol ester-stimulated B-1 cells, in a manner dependent on intact transcription/translation, but was not increased in phorbol ester- stimulated B-2 cells. Phorbol ester-stimulated cyclin D2 expression was accompanied by the formation of cyclin D2-Cdk4, and, to a lesser extent, cyclin D2-Cdk6, complexes; cyclin D2- containing complexes were found to be catalytically functional, in terms of their ability to phosphorylate exogenous Rb in vitro and to specifically phosphorylate endogenous Rb on serine780 in vivo. These results strongly suggest that the rapid induction of cyclin D2 by a normally nonmitogenic phorbol ester stimulus is responsible for B-1 cell progression through G1 phase. The ease and rapidity with which cyclin D2 responds in B-1 cells may contribute to the proliferative features of this subset.


Assuntos
Subpopulações de Linfócitos B/metabolismo , Ciclinas/biossíntese , Proteínas Proto-Oncogênicas , Animais , Subpopulações de Linfócitos B/citologia , Subpopulações de Linfócitos B/efeitos dos fármacos , Ciclina D2 , Quinase 4 Dependente de Ciclina , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Fase G1 , Técnicas In Vitro , Cinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitógenos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fase S , Acetato de Tetradecanoilforbol/farmacologia
19.
Neurooncol Pract ; 7(3): 320-328, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32528713

RESUMO

BACKGROUND: Meningioma is the most common primary intracranial tumor. It is usually slow growing and benign, and surgery is the main treatment modality. There are limited data on return to work following meningioma surgery. The objective of this study was to determine the patterns of sick-leave rate prior to surgery, and up to 2 years after, in patients compared to matched controls. METHODS: Data on patients ages 18 to 60 years with histologically verified intracranial meningioma between 2009 and 2015 were identified in the Swedish Brain Tumor Registry (SBTR) and linked to 3 national registries after 5 matched controls were assigned to each patient. RESULTS: We analyzed 956 patients and 4765 controls. One year prior to surgery, 79% of meningioma patients and 86% of controls were working (P < .001). The proportion of patients at work 2 years after surgery was 57%, in contrast to 84% of controls (P < .001). Statistically significant negative predictors for return to work in patients 2 years after surgery were high (vs low) tumor grade, previous history of depression, amount of sick leave in the year preceding surgery, and surgically acquired neurological deficits. CONCLUSION: There is a considerable risk for long term sick leave 2 years after meningioma surgery. Neurological impairment following surgery was a modifiable risk factor increasing the risk for long-term sick leave. More effective treatment of depression may facilitate return to work in this patient group.

20.
J Cell Biol ; 121(1): 101-11, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8458862

RESUMO

In mammalian cells inhibition of the cdc2 function results in arrest in the G2-phase of the cell cycle. Several cdc2-related gene products have been identified recently and it has been hypothesized that they control earlier cell cycle events. Here we have studied the relationship between activation of one of these cdc2 homologs, the cdk2 protein kinase, and the progression through the cell cycle in cultured human fibroblasts. We found that cdk2 was activated and specifically localized to the nucleus during S phase and G2. Microinjection of affinity-purified anti-cdk2 antibodies but not of affinity-purified anti-cdc2 antibodies, during G1, inhibited entry into S phase. The specificity of these effects was demonstrated by the fact that a plasmid-driven cdk2 overexpression counteracted the inhibition. These results demonstrate that the cdk2 protein kinase is involved in the activation of DNA synthesis.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Ciclo Celular/fisiologia , Quinases Ciclina-Dependentes , Fibroblastos/citologia , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases , Sequência de Aminoácidos , Especificidade de Anticorpos , Linhagem Celular , Quinase 2 Dependente de Ciclina , Replicação do DNA , Imunofluorescência , Humanos , Cinética , Microinjeções , Dados de Sequência Molecular , Inibidores de Proteínas Quinases , Proteínas Quinases/imunologia
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