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1.
Eur J Haematol ; 95(3): 254-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25808090

RESUMO

A 62-yr-old man with two healthy daughters was diagnosed with osteomyelofibrosis. To our surprise, a female XX-karyotype was observed in bone marrow and confirmed in PHA-stimulated T-lymphocytes from peripheral blood. Further molecular genetic investigation revealed a submicroscopic translocation between the short arm of X and Y, which leads to an XX-male genotype based on an unbalanced translocation X;Y. This rare coincidence was further accentuated as the USP9Y gene, suspected to be to be involved in sperm cell production, was absent, but no azoospermia was present. In general, routine cytogenetics may result in findings that need to be further delineated and, as here, lead to a rare observation.


Assuntos
Genótipo , Cariótipo , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Pessoa de Meia-Idade , Fenótipo , Análise para Determinação do Sexo , Linfócitos T/metabolismo
2.
Oncol Res Treat ; 46(6): 227-235, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37054696

RESUMO

INTRODUCTION: The timing of tumor-specific palliative therapy and its influence on the survival of patients with stage IV lung cancer remain unclear. METHODS: 375 patients with stage IV lung cancer who experienced an early or delayed therapy (early or delayed therapy group [TG]) were investigated using histology and ECOG performance score (ECOG-PS)-related subgroups. Kaplan-Meier and Cox regression analyses were used for survival analyses. RESULTS: Patients in the early TG had a significantly shorter median overall survival (OS) than those in the delayed TG (6 vs. 11 months). Patients with an ECOG-PS of ≥1 were significantly more present in the early TG than in the delayed TG (66.8 vs. 51.9%). But an early therapy was also significantly associated to a shorter median OS in ECOG-matched subgroups (ECOG-PS of 0, 7 vs. 23 months; ECOG ≥1, 6 vs. 8 months). An early therapy was associated to a significantly worse median OS in histological subgroups (NSCLC, 5 vs. 11 months; SCLC, 7 vs. 11 months) and was an independent risk factor in uni- and multivariate analyses. CONCLUSIONS: An early initiation of cancer-specific therapy was associated with a shorter survival time in palliative lung cancer patients, independent of the ECOG-PS and histological subtype.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Estudos Retrospectivos , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Análise de Sobrevida , Fatores de Risco , Prognóstico
3.
J Cell Physiol ; 226(11): 2762-81, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21302297

RESUMO

Chemotherapy remains a commonly used therapeutic approach for many cancers. Indeed chemotherapy is relatively effective for treatment of certain cancers and it may be the only therapy (besides radiotherapy) that is appropriate for certain cancers. However, a common problem with chemotherapy is the development of drug resistance. Many studies on the mechanisms of drug resistance concentrated on the expression of membrane transporters and how they could be aberrantly regulated in drug resistant cells. Attempts were made to isolate specific inhibitors which could be used to treat drug resistant patients. Unfortunately most of these drug transporter inhibitors have not proven effective for therapy. Recently the possibilities of more specific, targeted therapies have sparked the interest of clinical and basic researchers as approaches to kill cancer cells. However, there are also problems associated with these targeted therapies. Two key signaling pathways involved in the regulation of cell growth are the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways. Dysregulated signaling through these pathways is often the result of genetic alterations in critical components in these pathways as well as mutations in upstream growth factor receptors. Furthermore, these pathways may be activated by chemotherapeutic drugs and ionizing radiation. This review documents how their abnormal expression can contribute to drug resistance as well as resistance to targeted therapy. This review will discuss in detail PTEN regulation as this is a critical tumor suppressor gene frequently dysregulated in human cancer which contributes to therapy resistance. Controlling the expression of these pathways could improve cancer therapy and ameliorate human health.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Mutação , Transdução de Sinais/genética , Animais , Antineoplásicos/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Quinases raf/genética , Quinases raf/metabolismo
4.
Adv Biol Regul ; 77: 100739, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32773105

RESUMO

The COVID-19 pandemic has put a serious strain on health treatments as well at the economies of many nations. Unfortunately, there is not currently available vaccine for SARS-Cov-2/COVID-19. Various types of patients have delayed treatment or even routine check-ups and we are adapting to a virtual world. In many cases, surgeries are delayed unless they are essential. This is also true with regards to cancer treatments and screening. Interestingly, some existing drugs and nutraceuticals have been screened for their effects on COVID-19. Certain FDA approved drugs, vitamin, natural products and trace minerals may be repurposed to treat or improve the prevention of COVID-19 infections and disease progression. This review article will summarize how the treatments of various cancer patients has changed during the COVID-19 era as well as discuss the promise of some existing drugs and other agents to be repurposed to treat this disease.


Assuntos
Antineoplásicos/uso terapêutico , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Enzima de Conversão de Angiotensina 2 , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , COVID-19 , Comorbidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Reposicionamento de Medicamentos , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Hidroxicloroquina/uso terapêutico , Neoplasias/imunologia , Neoplasias/virologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , SARS-CoV-2 , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Oligoelementos/uso terapêutico , Vitaminas/uso terapêutico
5.
J Cell Physiol ; 221(1): 232-41, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19507191

RESUMO

Recent reports demonstrate that PKR is constitutively active in a variety of tumors and is required for tumor maintenance and growth. Here we report acute leukemia cell lines contain elevated levels of p-T451 PKR and PKR activity as compared to normal controls. Inhibition of PKR with a specific inhibitor, as well as overexpression of a dominant-negative PKR, inhibited cell proliferation and induced cell death. Interestingly, PKR inhibition using the specific inhibitor resulted in a time-dependent augmentation of AKT S473 and GSK-3alpha S21 phosphorylation, which was confirmed in patient samples. Increased phosphorylation of AKT and GSK-3alpha was not dependent on PI3K activity. PKR inhibition augmented levels of p-S473 AKT and p-S21/9 GSK-3alpha/beta in the presence of the PI3K inhibitor, LY294002, but was unable to augment GSK-3alpha or beta phosphorylation in the presence of the AKT inhibitor, A443654. Pre-treatment with the PKR inhibitor blocked the ability of A443654 and LY294002 to promote phosphorylation of eIF2alpha, indicating the mechanism leading to AKT phosphorylation and activation did not require eIF2alpha phosphorylation. The effects of PKR inhibition on AKT and GSK-3 phosphorylation were found to be, in part, PP2A-dependent. These data indicate that, in acute leukemia cell lines, constitutive basal activity of PKR is required for leukemic cell homeostasis and growth and functions as a negative regulator of AKT, thereby increasing the pool of potentially active GSK-3.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Leucemia/enzimologia , Leucemia/patologia , Proteína Fosfatase 2/metabolismo , eIF-2 Quinase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , eIF-2 Quinase/antagonistas & inibidores
6.
Dtsch Med Wochenschr ; 144(6): e42-e50, 2019 03.
Artigo em Alemão | MEDLINE | ID: mdl-30544270

RESUMO

BACKGROUND: For the prevention of cardiovascular risk factors (RF) there are numerous recommendations of professional societies, which relate to the personal way of life of individuals (for example nutrition/diet, physical activity, stress reduction etc.). The implementation of these recommendations is so far poor. In the ELITE study, data on RF, nutritional behavior, physical activity and quality of life in the Oldenburger Münsterland region are to be collected prospectively and improved by individual information. Reasons for the lack of implementation of preventive measures should be recognized. METHODS: The study is conducted as an interventional cohort study (DRKS-No.: 00 006 813, Ethics vote University of Göttingen). Up to 5000 people (with or without pre-existing RF) are aimed to be included. All participants receive a computer-generated report of their personal risk profile with detailed recommendations based on current guidelines. In addition, it is recommended to visit the family doctor to discuss the findings and, if necessary, initiate diagnostic or therapeutic measures. Every year, follow-up examinations take place for up to 5 years. RESULTS: By 31.12.2017 4602 participants (mean age 51.5 (±â€Š15.7) years, 53.7 % female) were admitted. Overweight were 39 % of the participants, obese 20.4 %. Most frequent anamnestic RF is hypertension (31.4 %), mean blood pressure was 138.4 ±â€Š16.6/83.0 ±â€Š9.9 mmHg. 2165 (47.0 %) participants show hypertensive blood pressure values. The second most frequent anamnestic RF are lipid metabolism disorders (16.6 %). CONCLUSION: The incidence of participants with at least one cardiovascular RF is very high (49.5 %, 16.6 % multiple RF). The incidence of RF is similar to other epidemiological data in Germany, so the ELITE collective allows a good comparison with other surveys.


Assuntos
Demência/prevenção & controle , Promoção da Saúde/métodos , Estilo de Vida , Infarto do Miocárdio/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Adulto , Idoso , Feminino , Seguimentos , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa
7.
Biochim Biophys Acta ; 1773(8): 1263-84, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17126425

RESUMO

Growth factors and mitogens use the Ras/Raf/MEK/ERK signaling cascade to transmit signals from their receptors to regulate gene expression and prevent apoptosis. Some components of these pathways are mutated or aberrantly expressed in human cancer (e.g., Ras, B-Raf). Mutations also occur at genes encoding upstream receptors (e.g., EGFR and Flt-3) and chimeric chromosomal translocations (e.g., BCR-ABL) which transmit their signals through these cascades. Even in the absence of obvious genetic mutations, this pathway has been reported to be activated in over 50% of acute myelogenous leukemia and acute lymphocytic leukemia and is also frequently activated in other cancer types (e.g., breast and prostate cancers). Importantly, this increased expression is associated with a poor prognosis. The Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways interact with each other to regulate growth and in some cases tumorigenesis. For example, in some cells, PTEN mutation may contribute to suppression of the Raf/MEK/ERK cascade due to the ability of activated Akt to phosphorylate and inactivate different Rafs. Although both of these pathways are commonly thought to have anti-apoptotic and drug resistance effects on cells, they display different cell lineage specific effects. For example, Raf/MEK/ERK is usually associated with proliferation and drug resistance of hematopoietic cells, while activation of the Raf/MEK/ERK cascade is suppressed in some prostate cancer cell lines which have mutations at PTEN and express high levels of activated Akt. Furthermore the Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways also interact with the p53 pathway. Some of these interactions can result in controlling the activity and subcellular localization of Bim, Bak, Bax, Puma and Noxa. Raf/MEK/ERK may promote cell cycle arrest in prostate cells and this may be regulated by p53 as restoration of wild-type p53 in p53 deficient prostate cancer cells results in their enhanced sensitivity to chemotherapeutic drugs and increased expression of Raf/MEK/ERK pathway. Thus in advanced prostate cancer, it may be advantageous to induce Raf/MEK/ERK expression to promote cell cycle arrest, while in hematopoietic cancers it may be beneficial to inhibit Raf/MEK/ERK induced proliferation and drug resistance. Thus the Raf/MEK/ERK pathway has different effects on growth, prevention of apoptosis, cell cycle arrest and induction of drug resistance in cells of various lineages which may be due to the presence of functional p53 and PTEN and the expression of lineage specific factors.


Assuntos
Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Animais , Apoptose , Ciclo Celular , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Masculino , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Estresse Oxidativo , Quinases raf/metabolismo
8.
Br J Haematol ; 141(1): 52-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18324966

RESUMO

Therapy-associated myelodysplastic syndromes and acute myeloid leukaemia (t-AML/MDS) following high dose chemotherapy are significant problems, with a cumulative incidence of 20% or more in myeloablative treatment regimen. Retrospective findings indicated that t-AML/MDS associated genetic aberrations can be observed directly after exposure to chemotherapy and can precede t-AML by several months. To determine the incidence of post-therapeutic aberrations and their predictive value, we prospectively investigated 316 samples of 95 patients with non-Hodgkin lymphoma (NHL) who were treated with intermediate and high dose chemotherapy (Arm A and B of the megaCHOEP (cyclophosphamide, doxorubicin, etoposide, vincristine, prednisolone) trial of the German High Grade NHL study group). Molecular aberrations (RUNX1/RUNX1T1, PML-RARA, CBFB-MYH11, MLL-MLLT1, BCR-ABL1) were observed in 33.3% (Arm A) and 55.4% (Arm B) of patients and in 14.9% and 28.7% of respective samples. Cytogenetic analysis of 53 NHL patients after high dose therapy showed frequent chromosomal breakage. Clonal aberrations were found in three patients. None of these patients developed a t-AML/MDS during a 3-year clinical follow up period. We concluded that the high incidence of genetic aberrations reflected a dose-dependent, transient therapy-induced genetic damage which is not predictive of a t-AML/MDS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Aberrações Cromossômicas/efeitos dos fármacos , Linfoma não Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Doxorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Seguimentos , Humanos , Leucemia Mieloide Aguda/induzido quimicamente , Linfoma não Hodgkin/genética , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Prognóstico , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Translocação Genética , Vincristina/uso terapêutico
9.
Med Klin (Munich) ; 102(5): 388-92, 2007 May 15.
Artigo em Alemão | MEDLINE | ID: mdl-17497090

RESUMO

BACKGROUND: Leukemic emboli in acute (AML) and chronic myelocytic leukemia (CML) are associated with hyperleukocytosis (>100,000/microl leukocytes) and most frequently detected at autopsy. They mainly occur in the small- and middle-sized arteries of lung and brain. Less frequently, leukemic emboli have also been observed in the cardiac chambers. The occlusion of large arteries by a leukemic embolus is a rare event. CASE REPORT: A 53-year-old woman was admitted with hyperleukocytosis and acute pain in her right leg. An occlusion of the right femoral arteries as the presenting symptom of a de novo AML (FAB M1/WHO: AML without maturation) with hyperleukocytosis was diagnosed. CONCLUSION: Leukemic emboli of large vessels are uncommon in leukemia with hyperleukocytosis. Most frequently, small- and middle-sized vessels of the brain and lung are affected. Leukemic emboli mainly occur in AML and CML in blast crisis and are rare in acute (ALL) and chronic lymphocytic leukemia (CLL). Risk factors are hyperleukocytosis and the expression of adhesion surface molecules which modulate blast-blast and endothelium interaction. Therapeutic options, apart from the immediate start of chemotherapy, are leukapheresis and embolectomy.


Assuntos
Arteriopatias Oclusivas/etiologia , Artéria Femoral , Leucemia Mieloide Aguda/diagnóstico , Células Neoplásicas Circulantes , Angiografia , Arteriopatias Oclusivas/patologia , Testes de Coagulação Sanguínea , Diagnóstico Diferencial , Feminino , Artéria Femoral/patologia , Células Precursoras de Granulócitos/patologia , Humanos , Leucemia Mieloide Aguda/patologia , Contagem de Leucócitos , Leucocitose/diagnóstico , Leucocitose/patologia , Pessoa de Meia-Idade , Células Neoplásicas Circulantes/patologia
10.
Leuk Res ; 30(9): 1091-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16540167

RESUMO

AML-associated MLL-PTD contribute to leukemogenesis by a gain of function and confer an unfavorable prognosis. Like other leukemia associated aberrations they are also present in healthy adults. To delineate the leukemogenic mechanism we tracked down MLL-PTD in normal hematopoiesis and investigated cord blood samples. MLL-PTD were observed in 56/60 (93%) of all cord bloods. In contrast to AML, the transcript frequency in cord blood was four log scales lower as determined by real-time PCR. The CD34+ progenitor cell, CD33+ myeloid, CD19+ B-lymphoid and CD3+ T-lymphoid subfractions were positive. The ubiquitous presence of MLL-PTD in cord blood implicates a lifelong exposure, not an accumulation during lifetime. Since also present in the stem cell subfraction, these factors seem not to be major determinants in MLL-PTD leukemogenesis.


Assuntos
Duplicação Gênica , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Adulto , Antígenos CD/metabolismo , Linfócitos B/metabolismo , Linfócitos B/patologia , Feminino , Sangue Fetal/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Histona-Lisina N-Metiltransferase , Humanos , Recém-Nascido , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Masculino , Linfócitos T/metabolismo , Linfócitos T/patologia
11.
Rev Iberoam Micol ; 23(2): 94-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16854185

RESUMO

Currently, susceptibility testing of Aspergillus isolates towards caspofungin is hampered by a lack of interpretative cut-off values. Nevertheless, caspofungin has been widely recommended for the treatment of invasive aspergillosis. This antifungal, however, could lead to therapy failure as demonstrated by the case in this report of a 55-year-old patient, who eight months after the diagnosis of leukemia and successful allogenic hematopoietic stem cell transplantation (HSCT), succumbed to a fatal pulmonary aspergillosis infection, which resisted treatment with caspofungin.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Pneumopatias Fúngicas/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Complicações Pós-Operatórias/tratamento farmacológico , Doença Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aspergilose/etiologia , Doenças da Medula Óssea/induzido quimicamente , Doenças da Medula Óssea/imunologia , Candidíase/complicações , Candidíase/tratamento farmacológico , Caspofungina , Terapia Combinada , Contraindicações , Equinocandinas , Evolução Fatal , Feminino , Transplante de Células-Tronco Hematopoéticas , Hepatite/complicações , Hepatite/microbiologia , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Leucemia Mieloide/complicações , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/cirurgia , Lipopeptídeos , Pneumopatias Fúngicas/etiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Pirimidinas , Esplenopatias/complicações , Esplenopatias/microbiologia , Triazóis , Voriconazol
12.
Leuk Lymphoma ; 46(2): 265-72, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15621811

RESUMO

AML1-ETO is generated by the t(8;21) translocation found in approximately 12% of acute myelogenous leukemia. Studies to delineate the mechanism by which AML1-ETO induces leukemia have primarily relied on transformed human cell lines or murine model systems. The goal of this study was to determine the effect of AML1-ETO expression on primary human hematopoietic cells in vitro and in a xenograft model. We used a FMEV retroviral vector for the transfer of AML1/ETO into human CD34 + cells. The repopulation, self-renewal, and differentiation potential of infected cells were assessed in serum-free liquid culture, colony assays, and in transplanted NOD-SCID mice. High transcription levels were confirmed by real-time PCR. AML1-ETO expressing cells were expandable for up to 12 weeks and retained an immature morphology. The capacity for prolonged survival, however, did not abrogate maturation, as AML1-ETO cells gave rise to normal colonies in a CFU-assay. AML1/ETO-expressing cells also contributed to myeloid (CD15, CD33), B-lymphoid (CD20), NK-cell (CD56) and erythroid (GPA) lineages in xenografted NOD/SCID mice. Although able to engraft all major lineages, AML1/ETO transplanted cells were primarily found in less differentiated fractions as measured by cell surface markers CD34 and CD38. In spite of a good engraftment and prolonged observation period none of the NOD/SCID-mice developed an acute myelogenous leukemia. Our findings demonstrate that AML1/ETO promotes the maintenance of early human hematopoietic progenitors, but does not abrogate their physiologic differentiation. Furthermore, the leukemogenic potential of AML1/ETO expressed in human progenitors is low, despite transcription levels equivalent to those found in AMLs.


Assuntos
Diferenciação Celular , Células-Tronco Hematopoéticas/citologia , Proteínas de Fusão Oncogênica/fisiologia , Fatores de Transcrição/fisiologia , Animais , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Subunidade alfa 2 de Fator de Ligação ao Core , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucemia/etiologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Fusão Oncogênica/genética , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/genética , Transfecção , Transplante Heterólogo
13.
Med Klin (Munich) ; 100(10): 672-5, 2005 Oct 15.
Artigo em Alemão | MEDLINE | ID: mdl-16220256

RESUMO

CASE REPORT: A 65-year-old patient with polycythemia vera (PV) was admitted with a painful edema of the right arm lasting for 24 h. The D-dimer assay was negative. By phlebography the patient was diagnosed with a fresh thrombosis of the right subclavian vein. 1 week later she developed a D-dimer-negative symptomatic pulmonary embolism. CONCLUSION: If clinical signs of a thromboembolic event are present, the negative predictive value of the D-dimer assay is not sufficient to abandon further definitive diagnosis. Since thromboembolic events are frequent in PV patients, a prophylactic treatment with low-dose acetylsalicylic acid is recommended.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Policitemia Vera/sangue , Embolia Pulmonar/sangue , Veia Subclávia , Trombose/sangue , Idoso , Braço/irrigação sanguínea , Diagnóstico Diferencial , Ecocardiografia , Feminino , Humanos , Flebografia , Policitemia Vera/complicações , Policitemia Vera/diagnóstico , Embolia Pulmonar/diagnóstico , Trombose/diagnóstico , Insuficiência da Valva Tricúspide/sangue , Insuficiência da Valva Tricúspide/complicações , Insuficiência da Valva Tricúspide/diagnóstico , Ultrassonografia Doppler em Cores
15.
Oncotarget ; 5(10): 2881-911, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24931005

RESUMO

The serine/threonine kinase glycogen synthase kinase-3 (GSK-3) was initially identified and studied in the regulation of glycogen synthesis. GSK-3 functions in a wide range of cellular processes. Aberrant activity of GSK-3 has been implicated in many human pathologies including: bipolar depression, Alzheimer's disease, Parkinson's disease, cancer, non-insulin-dependent diabetes mellitus (NIDDM) and others. In some cases, suppression of GSK-3 activity by phosphorylation by Akt and other kinases has been associated with cancer progression. In these cases, GSK-3 has tumor suppressor functions. In other cases, GSK-3 has been associated with tumor progression by stabilizing components of the beta-catenin complex. In these situations, GSK-3 has oncogenic properties. While many inhibitors to GSK-3 have been developed, their use remains controversial because of the ambiguous role of GSK-3 in cancer development. In this review, we will focus on the diverse roles that GSK-3 plays in various human cancers, in particular in solid tumors. Recently, GSK-3 has also been implicated in the generation of cancer stem cells in various cell types. We will also discuss how this pivotal kinase interacts with multiple signaling pathways such as: PI3K/PTEN/Akt/mTORC1, Ras/Raf/MEK/ERK, Wnt/beta-catenin, Hedgehog, Notch and others.


Assuntos
Quinase 3 da Glicogênio Sintase/fisiologia , Neoplasias/enzimologia , Animais , Humanos , Neoplasias/genética , Neoplasias/fisiopatologia
16.
Adv Enzyme Regul ; 47: 64-103, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17382374
18.
Curr Pharm Biotechnol ; 13(11): 2299-307, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21605067

RESUMO

Malignant gliomas, the most common malignant primary brain tumors, have a deleterious clinical prognosis of approximately 12 months in unselected series. The resistance against antineoplastic therapy is apparently not only associated with a high proliferative potential, marked antiapoptotic resistance and high migratory capacity. Effective mechanisms to escape the immune response of the organism and an intense neoangiogenesis also contribute to the aggressive growth of these neoplasms. In addition to a number of molecular mechanisms, the group of glycohydrate-binding galectins seems to contribute to the aggressive growth of malignant gliomas. Galectin-1, -3, -4 and -8 have been shown to be overexpressed in malignant gliomas. Galectin-1 is known to be involved in glioma cell migration and possibly also in proliferation. In this review, various aspects of glioma biology and their therapeutic relevance is discussed. The role of galectins in apoptosis-resistance, immune response and angiogenesis is discussed and explained why these molecules are interesting targets of glioma therapy.


Assuntos
Neoplasias Encefálicas/metabolismo , Galectinas/metabolismo , Glioma/metabolismo , Animais , Glicômica , Humanos
19.
Curr Pharm Des ; 18(13): 1784-95, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22394167

RESUMO

An area of therapeutic interest in cancer biology and treatment is targeting the cancer stem cell, more appropriately referred to as the cancer initiating cell (CIC). CICs comprise a subset of hierarchically organized, rare cancer cells with the ability to initiate cancer in xenografts in genetically modified murine models. CICs are thought to be responsible for tumor onset, self-renewal/maintenance, mutation accumulation and metastasis. CICs may lay dormant after various cancer therapies which eliminate the more rapidly proliferating bulk cancer (BC) mass. However, CICs may remerge after therapy is discontinued as they may represent cells which were either intrinsically resistant to the original therapeutic approach or they have acquired mutations which confer resistance to the primary therapy. In experimental mouse tumor transplant models, CICs have the ability to transfer the tumor to immunocompromised mice very efficiently while the BCs are not able to do so as effectively. Often CICs display increased expression of proteins involved in drug resistance and hence they are intrinsically resistant to many chemotherapeutic approaches. Furthermore, the CICs may be in a suspended state of proliferation and not sensitive to common chemotherapeutic and radiological approaches often employed to eliminate the rapidly proliferating BCs. Promising therapeutic approaches include the targeting of certain signal transduction pathways (e.g., RAC, WNT, PI3K, PML) with small molecule inhibitors or targeting specific cell-surface molecules (e.g., CD44), with effective cytotoxic antibodies. The existence of CICs could explain the high frequency of relapse and resistance to many currently used cancer therapies. New approaches should be developed to effectively target the CIC which could vastly improve cancer therapies and outcomes. This review will discuss recent concepts of targeting CICs in certain leukemia models.


Assuntos
Antineoplásicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Neoplasias/terapia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Animais , Humanos , Camundongos , Neoplasias/metabolismo
20.
Oncotarget ; 3(10): 1068-111, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23085539

RESUMO

The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Targeting these pathways is often complex and can result in pathway activation depending on the presence of upstream mutations (e.g., Raf inhibitors induce Raf activation in cells with wild type (WT) RAF in the presence of mutant, activated RAS) and rapamycin can induce Akt activation. Targeting with inhibitors directed at two constituents of the same pathway or two different signaling pathways may be a more effective approach. This review will first evaluate potential uses of Raf, MEK, PI3K, Akt and mTOR inhibitors that have been investigated in pre-clinical and clinical investigations and then discuss how cancers can become insensitive to various inhibitors and potential strategies to overcome this resistance.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Mutação/genética , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/genética , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Neoplasias/genética , Neoplasias/patologia , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Proteínas ras/antagonistas & inibidores , Proteínas ras/genética
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