OBJECTIVE To explore whether overexpression of human telomerase reverse transcriptase (hTERT) in Raji cells can protect against etoposide (VP 16)-induced apoptosis. METHODS A lipofectin-mediated gene transfection meth...OBJECTIVE To explore whether overexpression of human telomerase reverse transcriptase (hTERT) in Raji cells can protect against etoposide (VP 16)-induced apoptosis. METHODS A lipofectin-mediated gene transfection method was used to transfer the hTERT gene into Raji cells. The polymerase chain reaction enzyme-linked immunoassay was employed to determine telomerase activity. The expression levels of hTERT protein were assayed by immunofluorescence using a fluoresce isothiocyanate label. Cell viability was determined using the trypan blue dye exclusion assay. Apoptosis was assessed by morphological observation and flow cytometry analysis. RESULTS The results showed that there was a marked increase in both mean fluorescence intensity of hTERT-protein-positive cells and telomerase activity in hTERT- transfected Raji cells (P<0.05), but there was no difference in hTERT protein and telomerase activity levels between Raji cells and vectortransfected Raji cells (P>0.05). There were more viable cells at 48 h and 72 h after treatment of hTERT-transfected Raji cells with 10 10μmol/L VP-16 compared to either vector-transfected Raji cells and Raji cells (P<0.05). Apoptosis rates at 72 h after treatment with 10 μmol/L VP- 16 were 4.34 + 1.03% in hTERT-transfected Raji cells, 33.21 ± 3.12% in vector-transfected Raji cells, and 31.63 ± 3.06% in Raji cells. There was a significant difference in the percentage of apoptotic cells between hTERT-transfected Raji cells and either vector-transfected Raji cells or Raji cells (P<0.05). CONCLUSION Overexpression of telomerase by transfection of hTERT gene can protect against etoposide-induced apoptosis in Raji cells.展开更多
Objective： To evaluate the efficacy of ifosfamide and etoposide （VP-16） in patients with small cell lung cancer （SCLC）, and investigate the correlation between microvessel count （MVC） in tumor and chemotherapeu...Objective： To evaluate the efficacy of ifosfamide and etoposide （VP-16） in patients with small cell lung cancer （SCLC）, and investigate the correlation between microvessel count （MVC） in tumor and chemotherapeutic sensitivity. Methods： Forty-one consecutive cases of SCLC received chemotherapy of ifosfamide plus VP-16, and underwent investigation retrospectively. Immunohistochemistry using anti-human blood type H monoclonal antibody was conducted and MVC was recorded under light microscope. Results： There were 27 limited-disease and 14 extensive-disease patients. The overall response rate was 92.7% （38/41） with 28 cases （68.3%） of complete response （CR）, 10 （24.4%） with partial response （PR）, 3 （7.3%） with progressive disease （PD）. The 1-, 2-, 3-, and 5-year survival rates were 68.3% （28/41）, 48.3% （20/41）, 23.7% （9/38） and 11.1% （3/27）, respectively, with the median survival of 26.8 months. The principal toxicities were grade 3-4 neutropenia in 8 cases （19.5%）, grade 3-4 thrombocytopenia in 6 cases （14.6%）, mild liver toxicity in 7 cases （17.0%） and mild renal function damage in 4 cases （9.8%）. The mesenchymal vasculature was clearly visualized, with the mean value of 34.7 under each high microscopic power field. Of SCLC with more MVC （n=26）, CR accounted for 84.6%; while in cancers with less MVC （n=l 5）, CR took up 40.0%, with significant difference （P〈0.05）. Conclusion： Administrating ifosfamide and VP-16 is in accordance with the biological features of SCLC and results in beneficial results as well as acceptable side effects. The MVC is positively correlated with the chemotherapeutic sensitivity, and serves as a vital factor contributing to chemosensitivity.展开更多
程序性细胞死亡因子5(programmed celldeath5,PDCD5)在多种肿瘤细胞中表达明显降低。携带pdcd5基因的靶向增殖型腺病毒SG611-pdcd5对白血病细胞具有杀伤作用,对正常细胞具有相对保护作用。本研究旨在观察联合应用SG611-pdcd5与低剂量化...程序性细胞死亡因子5(programmed celldeath5,PDCD5)在多种肿瘤细胞中表达明显降低。携带pdcd5基因的靶向增殖型腺病毒SG611-pdcd5对白血病细胞具有杀伤作用,对正常细胞具有相对保护作用。本研究旨在观察联合应用SG611-pdcd5与低剂量化疗药物依托泊甙(etoposide,VP-16)对白血病细胞系K562的作用。以不同浓度梯度的药物或不同感染复数(multiplicity of infection,MOI)的病毒液作用于K562细胞,培养48小时后用MTT法检测细胞存活率。结果表明,与SG611-pdcd5(MOI=40)或VP-16(0.5μg/ml)单独作用组相比,SG611-pdcd5(MOI=40)+VP-16(0.5μg/ml)组细胞存活率明显降低(p均<0.05),分别为(59.45±4.12)%、(82.91±3.41)%及(42.00±5.75)%。SG611-pdcd5与VP-16的协同作用强于PDCD5蛋白或携带pdcd5基因的非增殖型腺病毒Ad-pdcd5与VP-16的协同作用(p均<0.05);VP-16浓度为4.0μg/ml时,VP-16+SG611-pdcd5(MOI=40)组、VP-16+proPDCD5(40μg/ml)组及VP-16+Ad-pdcd5(MOI=80)组细胞存活率分别为(37.09±1.89)%、(52.36±1.64)%及(73.64±4.33)%。结论:SG611-pdcd5具有促进低剂量VP-16杀伤K562细胞的作用,二者联合可增强对白血病细胞的杀伤作用。展开更多
文摘OBJECTIVE To explore whether overexpression of human telomerase reverse transcriptase (hTERT) in Raji cells can protect against etoposide (VP 16)-induced apoptosis. METHODS A lipofectin-mediated gene transfection method was used to transfer the hTERT gene into Raji cells. The polymerase chain reaction enzyme-linked immunoassay was employed to determine telomerase activity. The expression levels of hTERT protein were assayed by immunofluorescence using a fluoresce isothiocyanate label. Cell viability was determined using the trypan blue dye exclusion assay. Apoptosis was assessed by morphological observation and flow cytometry analysis. RESULTS The results showed that there was a marked increase in both mean fluorescence intensity of hTERT-protein-positive cells and telomerase activity in hTERT- transfected Raji cells (P<0.05), but there was no difference in hTERT protein and telomerase activity levels between Raji cells and vectortransfected Raji cells (P>0.05). There were more viable cells at 48 h and 72 h after treatment of hTERT-transfected Raji cells with 10 10μmol/L VP-16 compared to either vector-transfected Raji cells and Raji cells (P<0.05). Apoptosis rates at 72 h after treatment with 10 μmol/L VP- 16 were 4.34 + 1.03% in hTERT-transfected Raji cells, 33.21 ± 3.12% in vector-transfected Raji cells, and 31.63 ± 3.06% in Raji cells. There was a significant difference in the percentage of apoptotic cells between hTERT-transfected Raji cells and either vector-transfected Raji cells or Raji cells (P<0.05). CONCLUSION Overexpression of telomerase by transfection of hTERT gene can protect against etoposide-induced apoptosis in Raji cells.
基金This work was supported by a grant from the Education Department of P.R.China (No. 2004[527]).
文摘Objective： To evaluate the efficacy of ifosfamide and etoposide （VP-16） in patients with small cell lung cancer （SCLC）, and investigate the correlation between microvessel count （MVC） in tumor and chemotherapeutic sensitivity. Methods： Forty-one consecutive cases of SCLC received chemotherapy of ifosfamide plus VP-16, and underwent investigation retrospectively. Immunohistochemistry using anti-human blood type H monoclonal antibody was conducted and MVC was recorded under light microscope. Results： There were 27 limited-disease and 14 extensive-disease patients. The overall response rate was 92.7% （38/41） with 28 cases （68.3%） of complete response （CR）, 10 （24.4%） with partial response （PR）, 3 （7.3%） with progressive disease （PD）. The 1-, 2-, 3-, and 5-year survival rates were 68.3% （28/41）, 48.3% （20/41）, 23.7% （9/38） and 11.1% （3/27）, respectively, with the median survival of 26.8 months. The principal toxicities were grade 3-4 neutropenia in 8 cases （19.5%）, grade 3-4 thrombocytopenia in 6 cases （14.6%）, mild liver toxicity in 7 cases （17.0%） and mild renal function damage in 4 cases （9.8%）. The mesenchymal vasculature was clearly visualized, with the mean value of 34.7 under each high microscopic power field. Of SCLC with more MVC （n=26）, CR accounted for 84.6%; while in cancers with less MVC （n=l 5）, CR took up 40.0%, with significant difference （P〈0.05）. Conclusion： Administrating ifosfamide and VP-16 is in accordance with the biological features of SCLC and results in beneficial results as well as acceptable side effects. The MVC is positively correlated with the chemotherapeutic sensitivity, and serves as a vital factor contributing to chemosensitivity.
文摘程序性细胞死亡因子5(programmed celldeath5,PDCD5)在多种肿瘤细胞中表达明显降低。携带pdcd5基因的靶向增殖型腺病毒SG611-pdcd5对白血病细胞具有杀伤作用,对正常细胞具有相对保护作用。本研究旨在观察联合应用SG611-pdcd5与低剂量化疗药物依托泊甙(etoposide,VP-16)对白血病细胞系K562的作用。以不同浓度梯度的药物或不同感染复数(multiplicity of infection,MOI)的病毒液作用于K562细胞,培养48小时后用MTT法检测细胞存活率。结果表明,与SG611-pdcd5(MOI=40)或VP-16(0.5μg/ml)单独作用组相比,SG611-pdcd5(MOI=40)+VP-16(0.5μg/ml)组细胞存活率明显降低(p均<0.05),分别为(59.45±4.12)%、(82.91±3.41)%及(42.00±5.75)%。SG611-pdcd5与VP-16的协同作用强于PDCD5蛋白或携带pdcd5基因的非增殖型腺病毒Ad-pdcd5与VP-16的协同作用(p均<0.05);VP-16浓度为4.0μg/ml时,VP-16+SG611-pdcd5(MOI=40)组、VP-16+proPDCD5(40μg/ml)组及VP-16+Ad-pdcd5(MOI=80)组细胞存活率分别为(37.09±1.89)%、(52.36±1.64)%及(73.64±4.33)%。结论:SG611-pdcd5具有促进低剂量VP-16杀伤K562细胞的作用,二者联合可增强对白血病细胞的杀伤作用。
