RESUMEN
PURPOSE: Most guidelines about fertility preservation are predominantly focused on scientific evidence, but are less practically orientated. Therefore, practically oriented recommendations are needed to support the clinician in daily practice. METHODS: A selective literature search was performed based on the clinical and scientific experience of the authors, focussing on the most relevant diseases and gynaecological cancers. This article (Part I) provides information on topics that are essential for the fertility preservation indication, such as disease prognosis, disease therapy and its associated risks to fertility, recommending disease-specific fertility preservation measures. Part II specifically focusses on fertility preservation techniques. RESULTS: In breast cancer patients, fertility preservation such as ovarian tissue and oocyte cryopreservation is especially recommended in low-stage cancer and in women < 35 years of age. In Hodgkin's lymphoma, the indication is mainly based on the chemotherapy regime as some therapies have very low, others very high gonadotoxicity. In borderline ovarian tumours, preservation of fertility usually is achieved through fertility sparing surgery, ovarian stimulation may also be considered. In cervical cancer, endometrial cancer, rheumatic diseases and other malignancies such as Ewing sarcoma, colorectal carcinoma, non-Hodgkin lymphoma, leukaemia etc., several other factors must be considered to enable an individual, stage-dependent decision. CONCLUSION: The decision for or against fertility preservation depends on the prognosis, the risks to fertility and individual factors such as prospective family planning.
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Preservación de la Fertilidad/métodos , Inducción de la Ovulación/métodos , Adulto , Femenino , Humanos , Estudios Prospectivos , Adulto JovenRESUMEN
BACKGROUND: Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD)-positive acute myeloid leukaemia (AML) relapsing after allogeneic stem cell transplantation (allo-SCT) has a dismal prognosis with limited therapeutic options. FLT3-ITD kinase inhibition is a reasonable but palliative experimental treatment alternative in this situation. Information on long-term outcome is not available. METHODS: We performed a long-term follow-up analysis of a previously reported cohort of 29 FLT3-ITD-positive AML patients, which were treated in relapse after allo-SCT with sorafenib monotherapy. FINDINGS: With a median follow-up of 7.5 years, 6 of 29 patients (21%) are still alive. Excluding one patient who received a second allo-SCT, five patients (17%) achieved sustained complete remissions with sorafenib. Four of these patients are in treatment-free remission for a median of 4.4 years. INTERPRETATION: Sorafenib may enable cure of a proportion of very poor risk FLT3-ITD-positive AML relapsing after allo-SCT.
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Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Leucemia Mieloide Aguda/terapia , Niacinamida/análogos & derivados , Compuestos de Fenilurea/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Trasplante de Células Madre/efectos adversos , Secuencias Repetidas en Tándem , Tirosina Quinasa 3 Similar a fms/genética , Adolescente , Adulto , Anciano , Antineoplásicos/efectos adversos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Alemania , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Niacinamida/efectos adversos , Niacinamida/uso terapéutico , Compuestos de Fenilurea/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Factores de Riesgo , Sorafenib , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento , Adulto JovenRESUMEN
The preferred type of post-remission therapy (PRT) in patients with acute myeloid leukemia (AML) in first complete remission (CR1) is a subject of continued debate, especially in patients at higher risk of nonrelapse mortality (NRM), including patients >40 years of age. We report results of a time-dependent multivariable analysis of allogenic hematopoietic stem cell transplantation (alloHSCT) (n=337) versus chemotherapy (n=271) or autologous HSCT (autoHSCT) (n=152) in 760 patients aged 40-60 years with AML in CR1. Patients receiving alloHSCT showed improved overall survival (OS) as compared with chemotherapy (respectively, 57±3% vs 40±3% at 5 years, P<0.001). Comparable OS was observed following alloHSCT and autoHSCT in patients with intermediate-risk AML (60±4 vs 54±5%). However, alloHSCT was associated with less relapse (hazard ratio (HR) 0.51, P<0.001) and better relapse-free survival (RFS) (HR 0.74, P=0.029) as compared with autoHSCT in intermediate-risk AMLs. AlloHSCT was applied following myeloablative conditioning (n=157) or reduced intensity conditioning (n=180), resulting in less NRM, but comparable outcome with respect to OS, RFS and relapse. Collectively, these results show that alloHSCT is to be preferred over chemotherapy as PRT in patients with intermediate- and poor-risk AML aged 40-60 years, whereas autoHSCT remains a treatment option to be considered in patients with intermediate-risk AML.
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Leucemia Mieloide Aguda/terapia , Adulto , Antineoplásicos/química , Supervivencia sin Enfermedad , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Inducción de Remisión , Riesgo , Factores de Tiempo , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo , Resultado del TratamientoRESUMEN
BACKGROUND: To report the long-term results of adjuvant treatment with one cycle of modified bleomycin, etoposide, and cisplatin (BEP) in patients with clinical stage I (CS I) nonseminomatous germ-cell tumors (NSGCT) at high risk of relapse. PATIENTS AND METHODS: In a single-arm, phase II clinical trial, 40 patients with CS I NSGCT with vascular invasion and/or >50% embryonal cell carcinoma in the orchiectomy specimen received one cycle of adjuvant BEP (20 mg/m(2) bleomycin as a continuous infusion over 24 h, 120 mg/m(2) etoposide and 40 mg/m(2) cisplatin each on days 1-3). Primary end point was the relapse rate. RESULTS: Median follow-up was 186 months. One patient (2.5%) had a pulmonary relapse 13 months after one BEP and died after three additional cycles of BEP chemotherapy. Three patients (7.5%) presented with a contralateral metachronous testicular tumor, and three (7.5%) developed a secondary malignancy. Three patients (7.5%) reported intermittent tinnitus and one had grade 2 peripheral polyneuropathy (2.5%). CONCLUSIONS: Adjuvant chemotherapy with one cycle of modified-BEP is a feasible and safe treatment of patients with CS I NSGCT at high risk of relapse. In these patients, it appears to be an alternative to two cycles of BEP and to have a lower relapse rate than retroperitoneal lymph node dissection. If confirmed by other centers, 1 cycle of adjuvant BEP chemotherapy should become a first-line treatment option for this group of patients.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioterapia Adyuvante/métodos , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias Testiculares/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Bleomicina/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Estudios de Seguimiento , Humanos , Masculino , Recurrencia Local de Neoplasia/epidemiología , Neoplasias de Células Germinales y Embrionarias/mortalidad , Neoplasias de Células Germinales y Embrionarias/cirugía , Neoplasias Primarias Secundarias/epidemiología , Orquiectomía , Neoplasias Testiculares/mortalidad , Neoplasias Testiculares/cirugía , Tiempo , Adulto JovenRESUMEN
BACKGROUND: Erythropoiesis-stimulating agents (ESAs) reduce the need for red blood cell transfusions; however, they increase the risk of thromboembolic events and mortality. The impact of ESAs on quality of life (QoL) is controversial and led to different recommendations of medical societies and authorities in the USA and Europe. We aimed to critically evaluate and quantify the effects of ESAs on QoL in cancer patients. METHODS: We included data from randomised controlled trials (RCTs) on the effects of ESAs on QoL in cancer patients. Randomised controlled trials were identified by searching electronic data bases and other sources up to January 2011. To reduce publication and outcome reporting biases, we included unreported results from clinical study reports. We conducted meta-analyses on fatigue- and anaemia-related symptoms measured with the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) and FACT-Anaemia (FACT-An) subscales (primary outcomes) or other validated instruments. RESULTS: We identified 58 eligible RCTs. Clinical study reports were available for 27% (4 out of 15) of the investigator-initiated trials and 95% (41 out of 43) of the industry-initiated trials. We excluded 21 RTCs as we could not use their QoL data for meta-analyses, either because of incomplete reporting (17 RCTs) or because of premature closure of the trial (4 RCTs). We included 37 RCTs with 10581 patients; 21 RCTs were placebo controlled. Chemotherapy was given in 27 of the 37 RCTs. The median baseline haemoglobin (Hb) level was 10.1 g dl(-1); in 8 studies ESAs were stopped at Hb levels below 13 g dl(-1) and in 27 above 13 g dl(-1). For FACT-F, the mean difference (MD) was 2.41 (95% confidence interval (95% CI) 1.39-3.43; P<0.0001; 23 studies, n=6108) in all cancer patients and 2.81 (95% CI 1.73-3.90; P<0.0001; 19 RCTs, n=4697) in patients receiving chemotherapy, which was below the threshold (≥ 3) for a clinically important difference (CID). Erythropoiesis-stimulating agents had a positive effect on anaemia-related symptoms (MD 4.09; 95% CI 2.37-5.80; P=0.001; 14 studies, n=2765) in all cancer patients and 4.50 (95% CI 2.55-6.45; P<0.0001; 11 RCTs, n=2436) in patients receiving chemotherapy, which was above the threshold (≥ 4) for a CID. Of note, this effect persisted when we restricted the analysis to placebo-controlled RCTs in patients receiving chemotherapy. There was some evidence that the MDs for FACT-F were above the threshold for a CID in RCTs including cancer patients receiving chemotherapy with Hb levels below 12 g dl(-1) at baseline and in RCTs stopping ESAs at Hb levels above 13 g dl(-1). However, these findings for FACT-F were not confirmed when we restricted the analysis to placebo-controlled RCTs in patients receiving chemotherapy. CONCLUSIONS: In cancer patients, particularly those receiving chemotherapy, we found that ESAs provide a small but clinically important improvement in anaemia-related symptoms (FACT-An). For fatigue-related symptoms (FACT-F), the overall effect did not reach the threshold for a CID.
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Anemia/tratamiento farmacológico , Fatiga/sangre , Hematínicos/uso terapéutico , Neoplasias/sangre , Anemia/sangre , Eritropoyesis/efectos de los fármacos , Humanos , Neoplasias/tratamiento farmacológico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoAsunto(s)
Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/terapia , Adulto , Envejecimiento , Antineoplásicos/uso terapéutico , Proteínas Potenciadoras de Unión a CCAAT/genética , Europa (Continente)/epidemiología , Estudios de Seguimiento , Humanos , Leucemia Promielocítica Aguda/epidemiología , Proteínas Nucleares/genética , Nucleofosmina , Medición de Riesgo , Translocación Genética/genética , Resultado del Tratamiento , Tirosina Quinasa 3 Similar a fms/genéticaRESUMEN
The c-Src kinase regulates cancer cell invasion through inhibitor of DNA binding/differentiation 1 (ID1). Src and ID1 are frequently overexpressed in human lung adenocarcinoma. The current study aimed at identifying microRNAs (miRNAs) involved in the Src-ID1 signaling in lung cancer. Incubation of lung cancer cells with the Src inhibitor saracatinib led to the upregulation of several miRNAs including miR-29b, which was the most highly upregulated miRNA with predicted binding to the ID1 3'-untranslated region (UTR). Luciferase reporter assays confirmed direct binding of miR-29b to the ID1 3'-UTR. Expression of miR-29b suppressed ID1 levels and significantly reduced migration and invasion. Expression of antisense-miR-29b (anti-miR-29b), on the other hand, enhanced ID1 mRNA and protein levels, and significantly increased lung cancer cell migration and invasion, a hallmark of the Src-ID1 pathway. The ectopic expression of ID1 in miR-29b-overexpressing cells was able to rescue the migratory potential of these cells. Both, anti-miR-29b and ID1 overexpression diminished the effects of the Src inhibitors saracatinib and dasatinib on migration and invasion. Saracatinib and dasatinib decreased c-Myc transcriptional repression on miR-29b and led to increased ID1 protein levels, whereas forced expression of c-Myc repressed miR-29b and induced ID1. In agreement, we showed direct recruitment of c-Myc to the miR-29b promoter. miR-29b was significantly downregulated in primary lung adenocarcinoma samples compared with matched alveolar lung tissue, and miR-29b expression was a significant prognostic factor for patient outcome. These results suggest that miR-29b is involved in the Src-ID1 signaling pathway, is dysregulated in lung adenocarcinoma and is a potential predictive marker for Src kinase inhibitors.
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Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Proteína 1 Inhibidora de la Diferenciación/genética , Neoplasias Pulmonares/genética , MicroARNs/genética , Transducción de Señal , Familia-src Quinasas/genética , Regiones no Traducidas 3' , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma del Pulmón , Línea Celular Tumoral , Movimiento Celular/genética , Perfilación de la Expresión Génica , Genes myc , Humanos , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , MicroARNs/metabolismo , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismoAsunto(s)
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/terapia , Adulto , Antineoplásicos/uso terapéutico , Europa (Continente)/epidemiología , Estudios de Seguimiento , Humanos , Inmunofenotipificación , Incidencia , Cariotipificación , Pronóstico , Medición de Riesgo , Prevención Secundaria , Trasplante de Células Madre , Resultado del TratamientoAsunto(s)
Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas/metabolismo , Transactivadores/metabolismo , Transcripción Genética , Antígenos CD34/metabolismo , Antineoplásicos/farmacología , Western Blotting , Diferenciación Celular , Inmunoprecipitación de Cromatina , Granulocitos/metabolismo , Granulocitos/patología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Antígenos de Histocompatibilidad Menor , Neutrófilos/metabolismo , Neutrófilos/patología , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transactivadores/antagonistas & inhibidores , Transactivadores/genética , Tretinoina/farmacología , Células Tumorales CultivadasRESUMEN
Under inflammatory conditions, neutrophil apoptosis is delayed due to survival-factor exposure, a mechanism that prevents the resolution of inflammation. One important proinflammatory cytokine involved in the regulation of neutrophil survival/activation is granulocyte-macrophage colony-stimulating factor (GM-CSF). Although GM-CSF mediates antiapoptotic effects in neutrophils, it does not prevent apoptosis, and the survival effect is both time dependent and limited. Here, we identified the proapoptotic Bcl-2 family member Bim as an important lifespan limiting molecule in neutrophils, particularly under conditions of survival factor exposure. Strikingly, GM-CSF induced Bim expression in both human and mouse neutrophils that was blocked by pharmacological inhibition of phosphatidylinositol-3 kinase (PI3K). Increased Bim expression was also seen in human immature bone marrow neutrophils as well as in blood neutrophils from septic shock patients; both cell populations are known to be exposed to GM-CSF under in vivo conditions. The functional role of Bim was investigated using Bim-deficient mouse neutrophils in the presence and absence of the survival cytokines interleukin (IL)-3 and GM-CSF. Lack of Bim expression resulted in a much higher efficacy of the survival cytokines to block neutrophil apoptosis. Taken together, these data demonstrate a functional role for Bim in the regulation of neutrophil apoptosis and suggest that GM-CSF and other neutrophil hematopoietins initiate a proapoptotic counterregulation that involves upregulation of Bim.
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Proteínas Reguladoras de la Apoptosis/metabolismo , Factor Estimulante de Colonias de Granulocitos/farmacología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Proteínas de la Membrana/metabolismo , Neutrófilos/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/genética , Proteína 11 Similar a Bcl2 , Células Cultivadas , Humanos , Interleucina-3/metabolismo , Proteínas de la Membrana/genética , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes , Sepsis/metabolismoRESUMEN
Death-associated protein kinase 2 (DAPK2) belongs to a family of proapoptotic Ca(2+)/calmodulin-regulated serine/threonine kinases. We recently identified DAPK2 as an enhancing factor during granulocytic differentiation. To identify transcriptional DAPK2 regulators, we cloned 2.7 kb of the 5'-flanking region of the DAPK2 gene. We found that E2F1 and Krüppel-like factor 6 (KLF6) strongly activate the DAPK2 promoter. We mapped the E2F1 and KLF6 responsive elements to a GC-rich region 5' of exon 1 containing several binding sites for KLF6 and Sp1 but not for E2F. Moreover, we showed that transcriptional activation of DAPK2 by E2F1 and KLF6 is dependent on Sp1 using Sp1/KLF6-deficient insect cells, mithramycin A treatment to block Sp1-binding or Sp1 knockdown cells. Chromatin immunoprecipitation revealed recruitment of Sp1 and to lesser extent that of E2F1 and KLF6 to the DAPK2 promoter. Activation of E2F1 in osteosarcoma cells led to an increase of endogenous DAPK2 paralleled by cell death. Inhibition of DAPK2 expression resulted in significantly reduced cell death upon E2F1 activation. Similarly, KLF6 expression in H1299 cells increased DAPK2 levels accompanied by cell death that is markedly decreased upon DAPK2 knockdown. Moreover, E2F1 and KLF6 show cooperation in activating the DAPK2 promoter. In summary, our findings establish DAPK2 as a novel Sp1-dependent target gene for E2F1 and KLF6 in cell death response.
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Proteínas Reguladoras de la Apoptosis/genética , Apoptosis , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Factor de Transcripción E2F1/fisiología , Factores de Transcripción de Tipo Kruppel/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Reguladoras de la Apoptosis/fisiología , Sitios de Unión , Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Células Cultivadas , Proteínas Quinasas Asociadas a Muerte Celular , Humanos , Factor 6 Similar a Kruppel , Regiones Promotoras Genéticas , Factor de Transcripción Sp1/fisiologíaRESUMEN
BACKGROUND: Extracapsular tumor spread (ECS) has been identified as a possible risk factor for breast cancer recurrence, but controversy exists regarding its role in decision making for regional radiotherapy. This study evaluates ECS as a predictor of local, axillary, and supraclavicular recurrence. PATIENTS AND METHODS: International Breast Cancer Study Group Trial VI accrued 1475 eligible pre- and perimenopausal women with node-positive breast cancer who were randomly assigned to receive three to nine courses of classical combination chemotherapy with cyclophosphamide, methotrexate, and fluorouracil. ECS status was determined retrospectively in 933 patients based on review of pathology reports. Cumulative incidence and hazard ratios (HRs) were estimated using methods for competing risks analysis. Adjustment factors included treatment group and baseline patient and tumor characteristics. The median follow-up was 14 years. RESULTS: In univariable analysis, ECS was significantly associated with supraclavicular recurrence (HR = 1.96; 95% confidence interval 1.23-3.13; P = 0.005). HRs for local and axillary recurrence were 1.38 (P = 0.06) and 1.81 (P = 0.11), respectively. Following adjustment for number of lymph node metastases and other baseline prognostic factors, ECS was not significantly associated with any of the three recurrence types studied. CONCLUSIONS: Our results indicate that the decision for additional regional radiotherapy should not be based solely on the presence of ECS.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Recurrencia Local de Neoplasia/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/radioterapia , Terapia Combinada , Ciclofosfamida/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Metástasis Linfática , Metotrexato/administración & dosificación , Estadificación de Neoplasias , Premenopausia , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
The transcription factor PU.1 is essential for terminal myeloid differentiation, B- and T-cell development, erythropoiesis and hematopoietic stem cell maintenance. PU.1 functions as oncogene in Friend virus-induced erythroleukemia and as tumor suppressor in acute myeloid leukemias. Moreover, Friend virus-induced erythroleukemia requires maintenance of PU.1 expression and the disruption of p53 function greatly accelerates disease progression. It has been hypothesized that p53-mediated expression of the p21(Cip1) cell cycle inhibitor during differentiation of pre-erythroleukemia cells promotes selection against p53 function. In addition to the blockage of erythroblast differentiation provided by increased levels of PU.1, we propose that PU.1 alters p53 function. We demonstrate that PU.1 reduces the transcriptional activity of the p53 tumor suppressor family and thus inhibits activation of genes important for cell cycle regulation and apoptosis. Inhibition is mediated through binding of PU.1 to the DNA-binding and/or oligomerization domains of p53/p73 proteins. Lastly, knocking down endogenous PU.1 in p53 wild-type REH B-cell precursor leukemia cells leads to increased expression of the p53 target p21(Cip1).
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Proteínas Proto-Oncogénicas/metabolismo , Transactivadores/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis , Western Blotting , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Inmunoprecipitación , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Isoformas de Proteínas , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , ARN Interferente Pequeño/farmacología , Transactivadores/antagonistas & inhibidores , Transactivadores/genética , Activación Transcripcional , Células Tumorales Cultivadas , Proteína Tumoral p73 , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
G protein-coupled receptor (GPR)109A (HM74A) is a G(i) protein-coupled receptor, which is activated by nicotinic acid (NA), a lipid-lowering drug. Here, we demonstrate that mature human neutrophils, but not eosinophils, express functional GPR109A receptors. The induction of the GPR109A gene appears to occur late in the terminal differentiation process of neutrophils, since a mixed population of immature bone marrow neutrophils did not demonstrate evidence for its expression. NA accelerated apoptosis in cultured neutrophils in a concentration-dependent manner, as assessed by phosphatidylserine redistribution, caspase-3 activation, and DNA fragmentation assays. The pro-apoptotic effect of NA was abolished by pertussis toxin, which was used to block G(i) proteins, suggesting a receptor-mediated mechanism. Activation of GPR109A by NA resulted in decreased levels of cyclic adenosine monophosphate (cAMP), most likely due to G(i)-mediated inhibition of adenylyl cyclase activity. NA-induced apoptosis was reversed by the addition of cell-permeable cAMP, pointing to the possibility that reduced cAMP levels promote apoptosis in neutrophils. Distal mechanism involved in this process may include the post-translational modification of members of the Bcl-2 family, such as dephosphorylation of pro-apoptotic Bad and antiapoptotic Mcl-1 proteins. Taken together, following maturation in the bone marrow, neutrophils express functional GPR109A receptors, which might be involved in the regulation of neutrophil numbers. Moreover, this study identified a new cellular target of NA and future drugs activating GPR109A receptors, the mature neutrophil.
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Apoptosis , AMP Cíclico/metabolismo , Neutrófilos/metabolismo , Neutrófilos/fisiología , Niacina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Nicotínicos/metabolismo , Eosinófilos/metabolismo , Humanos , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Proteínas de Neoplasias/metabolismo , Neutrófilos/citología , Niacina/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína Letal Asociada a bcl/metabolismoRESUMEN
In summary, the management of women diagnosed with leukaemia in pregnancy needs an interdisciplinary approach, including a careful oncological work-up as well as close monitoring of the pregnancy until delivery and beyond. Patients with acute leukaemias normally must receive anti-leukaemic treatment at full dosage prior to delivery, except for selected women diagnosed very close to term. Treatment should be avoided in the first trimester. The prognosis of pregnant women with acute leukaemia corresponds to that of an age-matched and diagnosis-matched non-pregnant cohort of patients, provided appropriate treatment is given. If given as of the second trimester, the typical chemotherapy regimes used for acute leukaemias imply acceptable acute toxicities to the fetus, with a somewhat increased risk of premature birth or developmental retardation, but no clear evidence of late sequelae in children and adolescents who were exposed to cytostatic agents whilst in utero. In chronic leukaemias and MDS, treatment may often be delayed until after delivery. In CML targeted therapy with imatinib mesylate is safe as of the second trimester, and possibly even before. Obstetric care and monitoring of women with leukaemia are essential throughout the pregnancy to ensure the best possible outcome for mother and child.