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BACKGROUND: The thoracic radiotherapy (TRT) target volume for limited-stage small-cell lung cancer (SCLC) has been controversial for decades. In this report, the final results of a prospective randomized trial on the TRT target volume before and after induction chemotherapy are presented. METHODS: After 2 cycles of etoposide and cisplatin, patients arm were randomized to receive TRT to the postchemotherapy or prechemotherapy tumor volume in a study arm and a control arm. Involved-field radiotherapy was received in both arms. TRT consisted of 1.5 grays (Gy) twice daily in 30 fractions to up to a total dose of 45 Gy. Lymph node regions were contoured, and intentional and incidental radiation doses were recorded. RESULTS: The study was halted early because of slow accrual. Between 2002 and 2017, 159 and 150 patients were randomized to the study arm or the control arm, respectively; and 21.4% and 19.1% of patients, respectively, were staged using positron emission tomography/computed tomography (P = .31). With a median follow-up of 54.1 months (range, 19.9-165.0 months) in survivors, the 3-year local/regional progression-free probability was 58.2% and 65.5% in the study and control arms, respectively (P = .44), and the absolute difference was -7.3% (95% CI, -18.2%, 3.7%). In the study and control arms, the median overall survival was 21.9 months and 26.6 months, respectively, and the 5-year overall survival rate was 22.8% and 28.1%, respectively (P = .26). Grade 3 esophagitis was observed in 5.9% of patients in the study arm versus 15.5% of those in the control arm (P = .01). The isolated out-of-field failure rate was 2.6% in the study arm versus 4.1% in the control arm (P = .46), and all such failures were located in the supraclavicular fossa or contralateral hilum. The regions 7, 3P, 4L, 6, 4R, 5, and 2L received incidental radiation doses >30 Gy. CONCLUSIONS: TRT could be limited to the postchemotherapy tumor volume, and involved-field radiotherapy could be routinely applied for limited-stage SCLC.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pulmonares/terapia , Dosificación Radioterapéutica , Carcinoma Pulmonar de Células Pequeñas/terapia , Adulto , Anciano , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Cisplatino/administración & dosificación , Etopósido/administración & dosificación , Femenino , Humanos , Leucopenia/etiología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neumonía/etiología , Estudios Prospectivos , Fibrosis Pulmonar/etiología , Informe de Investigación , Carcinoma Pulmonar de Células Pequeñas/patologíaRESUMEN
PURPOSE: The optimal radiotherapy dose/fraction for limited-stage small cell lung cancer (SCLC) is undefined. Our objectives were to compare efficacy between hyperfractionated thoracic radiotherapy (TRT; 1.5â¯Gy 2 times per day [bid] in 30 fractions) and hypofractionated TRT (2.5â¯Gy once per day [qd] in 22 fractions), and to explore prognostic factors influencing the prognosis, such as the timing of TRT. METHODS: Patients enrolled in two independent prospective studies were combined and analyzed. The primary endpoint was local/regional control (LRC). The prognosis was analyzed using the Cox proportional hazards regression model. RESULTS: Ninety-two and 96 patients were treated with hyperfractionated TRT and hypofractionated TRT, respectively. The 1 and 2year LRC rates of the two arms were 82.1 and 60.7%, and 84.9 and 68.8% (Pâ¯= 0.27), respectively. The median overall survival (OS) times (months) were 28.3 (95% confidence interval, CI 16.4-40.1) and 22.0 (95% CI 16.4-27.5), while the 1year, 3year, and 5year OS rates were 85.2, 40.8, and 27.1%, and 76.9, 34.3, and 26.8% (Pâ¯= 0.37), respectively. Using a multivariate Cox regression study, time (days) from the initiation of chemotherapy to TRT (TCT) ≤43 was associated with improved LRC (hazard radio, HR 0.39, 95% CI 0.20-0.76; Pâ¯= 0.005). Time (days) from the start of chemotherapy to the end of TRT (SER) ≤63 (HR 0.50, 95% CI 0.32-0.80; Pâ¯= 0.003) and prophylactic cranial irradiation (HR 0.43; 95% CI 0.29-0.63; Pâ¯= 0.000) were favorably related to OS. Grade 2/3 acute radiation esophagitis was observed in 37.0 and 17.7% of patients in the hyperfractionated and hypofractionated arms, respectively (Pâ¯= 0.003). CONCLUSION: Both hyperfractionated and hypofractionated TRT schedules achieved good LRC and OS for patients with limited-stage SCLC in this study. Keeping TCT ≤43 and SER ≤63 resulted in a better prognosis. The incidence of acute esophagitis was significantly higher in the hyperfractionated arm.
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Neoplasias Pulmonares/radioterapia , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Adulto , Anciano , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Pulmón/patología , Pulmón/efectos de la radiación , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Carcinoma Pulmonar de Células Pequeñas/diagnóstico , Carcinoma Pulmonar de Células Pequeñas/patología , Factores de TiempoRESUMEN
Correction to: Strahlenther Onkol 2019 https://doi.org/10.1007/s00066-019-01539-1 The original version of this article unfortunately contained a mistake. The correct version of the funding information are given .
RESUMEN
Vascular endothelial growth factor (VEGF) plays a critical role during normal embryonic angiogenesis and also in the pathological angiogenesis that occurs in a number of diseases, including cancer. K562 human leukemia cells overexpress VEGF, with a shift in isoform production from membrane-bound VEGF189 to the more soluble VEGF165. In the present study, three 19 bp reverse repeated motifs targeting exons 5 and 7 boundary of VEGF165 gene sequence with 9 bp spacer were synthesized and cloned into eukaryotic expression plasmid pGenesil-1 containing U6 shRNA promoter and termination signal of RNA polymerase. The recombinant plasmids pGenesil-VR1, pGenesil-VR2, pGenesil-VR3 and pGenesil-con (plasmid containing random DNA fragment) were transfected into K562 cells, respectively, through lipofectamine reagent. A vector-based small interfering RNA(SiRNA) inhibited VEGF165 mRNA expression by 72% and protein production by 67% in K562 cells. Human microvascular endothelial cell migration induced by conditioned medium from VEGFsi-transfected K562 cells was significantly less than that induced by conditioned medium from K562 cells and control vector-transfected K562 cells. Furthermore, the VEGF shRNA dramatically suppressed tumor angiogenesis and tumor growth in a K562 s.c. xenograft model. Vessel density as assessed by vWF immunohistochemical analysis was also decreased. This strategy provides a novel tool to study the function of various VEGF isoforms and may contribute to VEGF-specific treatment in cancer.
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Vectores Genéticos/genética , Leucemia Experimental/prevención & control , ARN Interferente Pequeño/genética , Factor A de Crecimiento Endotelial Vascular/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Apoptosis , Western Blotting , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Células K562 , Leucemia Experimental/genética , Leucemia Experimental/metabolismo , Ratones , Ratones Desnudos , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Isoformas de Proteínas , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Tasa de Supervivencia , Transfección , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
AIM: To evaluate the long-term effectiveness and late toxicities of paclitaxel (PTX) plus cisplatin (DDP) with concurrent radiotherapy for locally advanced esophageal squamous cancer. METHODS: Between 2008 and 2011, 76 patients were enrolled in a phase II study on the treatment of loco-regionally advanced esophageal cancer with radiotherapy (68.4 Gy/44 fractions or 61.2 Gy/34 fractions) combined with 4-cycle chemotherapy consisting of DDP (25 mg/m2 per day for 3 d) and PTX (175 mg/m2 for 3 h). The primary endpoints were overall survival and progression-free survival, and the secondary endpoints were toxicity and the treatment failure pattern. RESULTS: A total of 76 patients were enrolled in this study, of whom 63.2% finished the whole regimen. The 5-year survival rates for the per-protocol population and intent-to-treat population were 25.4% and 26.4%, respectively, and the median survival rates were 23.7 mo and 28.5 mo, respectively. Grade 3 or 4 late toxicity was observed in only one patient (heart failure). In log-rank analysis, the pretreatment stage (stage II + III: 36.1 mo vs stage IV: 14.9 mo) and the completed cycle (1-3 cycles: 16.1 mo vs 4 cycles: 35.5 mo) were significant prognostic factors (P = 0.037 < 0.05 and P = 0.013 < 0.05). CONCLUSION: Radiotherapy combined with chemotherapy consisting of PTX and DDP is a safe and effective definitive treatment for loco-regionally advanced esophageal squamous cancer.
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Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/terapia , Quimioradioterapia/métodos , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/terapia , Recurrencia Local de Neoplasia/terapia , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/patología , Quimioradioterapia/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Cisplatino/uso terapéutico , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Paclitaxel/uso terapéutico , Estudios Prospectivos , Dosificación Radioterapéutica , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
OBJECTIVE: To explore the potential effects of anti-VEGF hairpin ribozyme gene to gene expression profiles in leukemia cell line K562. METHODS: The lipofectamine mediation was used to transfect the recombinant eukaryotic expression plasmid (pcDNA3-RZ) containing anti-VEGF hairpin ribozyme gene and the non-recombinant vector as control into K562 cells. And the positive clones were screened by G418. Ribozyme gene in K562 cells was confirmed by PCR. Fluorescent real time reverse transcription-PCR(RT-PCR) and Western blotting were employed to detect the expression of VEGF mRNA and protein in leukemia cells. cDNA microarray was used to explore the alteration of gene expression profiles when decreasing VEGF gene expression in leukemia cells. Expression of PCNA and GSN genes were verified by semi-quantitative RT-PCR. RESULTS: The pcDNA3-RZ and pcDNA3 had been transfected into the human leukemia cell line K562 and positive clones been screened by G418. Stable expression of the ribozyme gene in K562 cells was confirmed by PCR. The level of VEGF mRNA and protein decreased dramatically in K562-RZ cells when compared with K562 or K562-PC (K562 cell transfected with empty vector) cells. The gene expression profiles were changed by transfection of anti-VEGF hairpin ribozyme gene into K562 cells. Among 4096 gene clones on the microarray, 191 (4.86%) genes were detected to have the marked changes with 104 down-regulated and 87 up-regulated, that were functionally related to cell cycle progression, gene replication, metabolism, cell apoptosis, cell signal transduction, and oncogenes etc. An increased expression of GSN gene and a decreased expression of PCNA gene in K562/RZ cells have been detected by RT-PCR. CONCLUSION: Down-regulation of VEGF gene by introducing anti-VEGF hairpin ribozyme gene can alter the gene expression profiles in K562 cells, leading to change of cell growth, differentiation and apoptosis in K562/RZ cells.
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Perfilación de la Expresión Génica , Expresión Génica/efectos de los fármacos , Leucemia/metabolismo , ARN Catalítico/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Humanos , Células K562 , Leucemia/genética , Leucemia/patología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
OBJECTIVES: A phase II study was performed to investigate the efficacy and the safety of a 3-week schedule of paclitaxel (PTX) plus cisplatin (DDP) combined with concurrent radiotherapy for esophageal squamous cell cancer. PATIENTS AND METHODS: Patients with newly diagnosed esophageal squamous cell cancer who had histologic proof of local-regional carcinoma of the esophagus, a Karnofsky performance status of 80 or greater, and normal liver, renal, and bone marrow functions were enrolled in the phase II trial. Chemotherapy consisted of DDP (25 mg/m/d) for 3 days plus PTX (175 mg/m) given for 3 hours, every 3 weeks for 4 cycles. The total dose of concurrent radiation with 68.4 Gy/44 Fx (late course-accelerated radiotherapy) or 61.2 Gy/34 Fx (conventional radiotherapy) was given at the first day of chemotherapy. RESULTS: Between July 2008 and November 2011, 76 patients were enrolled in this trial. The median age was 58 years (range, 37 to 74 y). The stages were stage II (21 patients), stage III (27 patients), and stage IV (28 patients). A total of 89.5% (68/76) and 63.2% (48/76) patients completed ≥2 cycles and all 4 cycles of chemotherapy, respectively. With the median follow-up of 36 months, the overall median survival time was 28.5 months and the progression-free survival time was 14.7 months. One- and 3-year survival rates were 75% and 41%, respectively. Neutropenia grade 3 and 4 occurred in 30.3% and 31.6% of the patients, respectively. CONCLUSIONS: Radiotherapy concurrent with a 3-week schedule of PTX and DDP resulted in an encouraging overall survival rate, but a relatively higher hematological toxicity.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/secundario , Quimioradioterapia , Cisplatino/administración & dosificación , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Neoplasias Esofágicas/patología , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neutropenia/inducido químicamente , Paclitaxel/administración & dosificación , Estudios Prospectivos , Tasa de SupervivenciaAsunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Núcleo Celular/metabolismo , Linfoma de Células B Grandes Difuso/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteína 1 de Unión a la Caja Y/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Citoplasma/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Adulto JovenRESUMEN
AIM: To elucidate high mobility group-box 3 (HMGB3) protein expression in gastric adenocarcinoma, its potential prognostic relevance, and possible mechanism of action. METHODS: Ninety-two patients with gastric adenocarcinomas surgically removed entered the study. HMGB3 expression was determined by immunohistochemistry through a tissue microarray procedure. The clinicopathologic characteristics of all patients were recorded, and regular follow-up was made for all patients. The inter-relationship of HMGB3 expression with histological and clinical factors was analyzed using nonparametric tests. Survival analysis was carried out by Kaplan-Meier (log-rank) and multivariate Cox (Forward LR) analyses between the group with overexpression of HMGB3 and the group with low or no HMGB3 expression to determine the prognosis value of HMGB3 expression on overall survival. Further, HMGB3 expression was knocked down by small hairpin RNAs (shRNAs) in the human gastric cancer cell line BGC823 to observe its influence on cell biological characteristics. The MTT method was utilized to detect gastric cancer cell proliferation changes, and cell cycle distribution was analyzed by flow cytometry. RESULTS: Among 92 patients with gastric adenocarcinomas surgically removed in this study, high HMGB3 protein expression was detected in the gastric adenocarcinoma tissues vs peritumoral tissues (P < 0.001). Further correlation analysis with patients' clinical and histology variables revealed that HMGB3 overexpression was obviously associated with extensive wall penetration (P = 0.005), a positive nodal status (P = 0.004), and advanced tumor-node-metastasis (TNM) stage (P = 0.001). But there was no correlation between HMGB3 overexpression and the age and gender of the patient, tumor localization or histologic grade. Statistical Kaplan-Meier survival analysis disclosed significant differences in overall survival between the HMGB3 overexpression group and the HMGB3 no or low expression group (P = 0.006). The expected overall survival time was 31.00 ± 3.773 mo (95%CI = 23.605-38.395) for patients with HMGB3 overexpression and 49.074 ± 3.648 mo (95%CI = 41.925-57.311) for patients with HMGB3 no and low-level expression. Additionally, older age (P = 0.040), extensive wall penetration (P = 0.008), positive lymph node metastasis (P = 0.005), and advanced TNM tumor stage (P = 0.007) showed negative correlation with overall survival. Multivariate Cox regression analysis indicated that HMGB3 overexpression was an independent variable with respect to age, gender, histologic grade, extent of wall penetration, lymph nodal metastasis, and TNM stage for patients with resectable gastric adenocarcinomas with poor prognosis (hazard ratio = 2.791, 95%CI = 1.233-6.319, P = 0.019). In the gene function study, after HMGB3 was knocked down in the gastric cell line BGC823 by shRNA, the cell proliferation rate was reduced at 24 h, 48 h and 72 h. Compared to BGC823 shRNA-negative control (NC) cells, the cell proliferation rate in cells that had HMGB3 shRNA transfected was significantly decreased (P < 0.01). Finally, cell cycle analysis by FACS showed that BGC823 cells that had HMGB3 knocked down were blocked in G1/G0 phase. The percentage of cells in G1/G0 phase in BGC823 cells with shRNA-NC and with shRNA-HMGB3 was 46.84% ± 1.7%, and 73.03% ± 3.51% respectively (P = 0.001), whereas G2/M cells percentage decreased from 26.51% ± 0.83% to 17.8% ± 2.26%. CONCLUSION: HMGB3 is likely to be a useful prognostic marker involved in gastric cancer disease onset and progression by regulating the cell cycle.
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Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Regulación Neoplásica de la Expresión Génica , Proteína HMGB3/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirugía , Anciano , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , Modelos de Riesgos Proporcionales , Interferencia de ARN , Resultado del TratamientoRESUMEN
The aim of study was to investigate the expression of CD36 in leukemia cells and to explore its significance in diagnosis and differential diagnosis for leukemia in patients. Blood samples from 133 cases of leukemias were analyzed by CD45/SSC double parameters and multi-color flow cytometry in order to determine the CD36 and other leukocyte differentiation antigens. The results show that the CD36 positive rate was 21.8% (29/133) in 133 cases of leukemia, 41.9% (26/62) in 62 cases of AML (acute myeloid leukemia), and none of the 54 cases of lymphocytic leukemia was positive for this antigen. The positive rate of CD36 in M(4) (8/10), M(5) (12/12) and M(6) (3/3) was significantly higher than that in M(1) (0/9), M(2) (3/12), M(3) (0/16) (all P < 0.001). The percent of positive cells of CD36 in M(5a) was significantly higher than in M(5b) (P = 0.001). A significantly negative regression was found between CD36 and CD117 in AML (r = -0.751, P = 0.005). And a significantly positive regression was found between CD36 and CD14 in M(4) and M(5b) (r = 0.870, P = 0.011). In monocyte lineage involved leukemia (MLIL), the positive rate of CD36 (92.6%, 25/27) was significantly higher than that of CD14 (48.1%, 13/27)(P = 0.001). None of the 7 cases with M(5a) was positive for CD14, but 4 of 5 cases of M(5b) were positive. The positive rate of CD117 in M(5a) was significantly higher than that of in M(5b)(P = 0.01). The positive rate of CD34 in M(5) was low (33.3%, 4/12). It is concluded that the combination of CD36 with lymphoid and myeloid antigens is helpful to the diagnosis and differential diagnosis of lymphoid, myeloid and MLIL. The positive rate of CD36 is higher than that of CD14 in MLIL.
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Antígenos CD36/análisis , Citometría de Flujo/métodos , Leucemia Monocítica Aguda/inmunología , Leucemia Mieloide Aguda/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Inmunofenotipificación , Lactante , Receptores de Lipopolisacáridos/análisis , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Proteínas Proto-Oncogénicas c-kit/análisisRESUMEN
OBJECTIVE: lo investigate the effects of anti-VEGF antibody and anti-VEGF hairpin ribozyme gene on the proliferation, apoptosis and related gene expression of the leukemia K562 cells and the possible molecular mechanisms. METHODS: K562 cells were cultured in different concentrations of anti-VEGF antibody. The recombinant eukaryotic expression plasmid (pcDNA3-RZ) containing anti-VEGF hairpin ribozyme gene and the vector-alone were introduced into K562 cells by lipofectamine mediation. Cell proliferative capacity was determined by MTT, colony formation assay and cells cycles analysis. Cell apoptosis was assayed by DNA ladder and Annexin V -FITC/PI flow cytometry. RESULTS: The anti-VEGF antibody was able to inhibit growth and induce apoptosis of K562 cells in a dose-dependent manner. Exposure to anti-VEGF antibody at 0. 165 microg/ml for 72 hours, the cells exhibited typical DNA ladders. The apoptosis rate peaked at antibody concentration of 0. 825 microg/ml. RT-PCR showed a decrease of MRP and TOPO II expression but a relative constant expression of GST. The introduction of exogenous anti-VEGF ribozyme gene resulted in a decrease of the proliferative capacity and colony forming efficiency from (30.5 +/- 3.3) % in control group to (16.3 +/- 2.8) % in K562/RZ group, higher G1 and lower S ratio in cell cycle distribution in comparison with the control groups. Typical DNA fragmentation and higher Annexin V + ratio occurred in K562/RZ cells after treated with 0.5 micromot/L of As2O3 for 3 days, the apoptosis rate increased from 13.4% in control group to 31. 5% in As2O3 treated group. CONCLUSION: Anti-VEGF antibody can inhibit growth, induce apoptosis and down-regulate the expression of MRP, TOPO II genes of K562 cells in vitro. Transfection with anti-VEGF ribozyme gene can inhibit the proliferation of the cells by delaying the progression G1 into S phase in cell cycles and induce cell apoptosis by down-regulating VEGF gene expression.
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Anticuerpos/farmacología , ARN Catalítico/genética , Factor A de Crecimiento Endotelial Vascular/inmunología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación de la Expresión Génica , Vectores Genéticos , Humanos , Células K562 , Liposomas , Transfección , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
To investigate the mechanism of proliferation inhibition and apoptosis of K562 leukemia cells by lithium chloride (LiCl), after K562 cells were treated with LiCl (30 mmol/L) cell cycle was examined by flow cytometry (FCM) and the expression of bcr/abl fusion gene mRNA was evaluated by RT-PCR. The intracellular Li(+) concentrations of K562 cells were determined at different time after treated with 30 mmol/L LiCl and the effects of TTX and FSK on intracellular Li(+) concentrations of K562 cells were also detected by atomic absorption spectrometry. The effects of TTX and FSK on LiCl-induced growth inhibition of K562 cells were determined by cell counting in liquid culture. The results showed that LiCl (30 mmol/L) caused a sustained arrest in G(2)/M cell cycle and down-regulated the bcr/abl mRNA expression in K562 cells, the intracellular Li(+) concentration of K562 cells increased at 30 minutes after treated with 30 mmol/L LiCl and reached apex at 2 hours, thereafter, gradually decreased and balanced at 4 hours after the treatment. If either Na(+) channel was pre-blocked with TTX or K(+) channel was pre-blocked with FSK, the intracellular Li(+) concentrations of K562 cells treated with 30 mmol/L LiCl were higher than that in the cells just treated with LiCl without pre-blocking. Furthermore, after pre-blocking either Na(+) channel with TTX or K(+) channel with FSK, the inhibition rate of K562 cell growth by 30 mmol/L LiCl could be increased. It is concluded that the mechanism of proliferation inhibition and apoptosis of K562 leukemia cells induced by LiCl is probably related with the G(2)/M cell cycle arrest, the bcr/abl mRNA expression down-regulation and the status of Na(+), K(+), or Li(+) ion channels on K562 leukemia cells.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cloruro de Litio/farmacología , Ciclo Celular/efectos de los fármacos , Colforsina/farmacología , Citometría de Flujo , Proteínas de Fusión bcr-abl/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células K562 , Leucemia/genética , Leucemia/metabolismo , Leucemia/patología , Bloqueadores de los Canales de Potasio/farmacología , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Bloqueadores de los Canales de Sodio/farmacología , Tetrodotoxina/farmacologíaRESUMEN
OBJECTIVE: To investigate the effects of lithium chloride on the proliferation and apoptosis of human leukemia cell line (K562). METHODS: The effects of lithium chloride on the proliferation of K562 leukemia cells were evaluated by liquid culture assay, MTT assay, and colony formation assay. The effects of lithium chloride on the apoptosis of K562 leukemia cell were verified by cellular morphology and the agarose gel electrophoresis of DNA fragments. RESULTS: 1. The proliferation of K562 leukemia cells was inhibited by lithium chloride (10-50 mmol/L) in a dose-dependent manner. 2. With lithium chloride (30 mmol/L), the apoptosis cells could be observed in cellular morphology, and DNA ladder was also observed in agarose gel electrophoresis. CONCLUSION: Lithium chloride can inhibit the proliferation of K562 cells and cause the apoptosis of K562 cells.