Objective： To investigate the effect of paclitaxel on cell proliferation and apoptosis of human lung adenocarcinoma A549 cells line and its mechanism in vitro. Methods ： Cell growth inhibition of paclitaxel on A549 ...Objective： To investigate the effect of paclitaxel on cell proliferation and apoptosis of human lung adenocarcinoma A549 cells line and its mechanism in vitro. Methods ： Cell growth inhibition of paclitaxel on A549 cells was analyzed by MTT assay. Cell apoptosis was detected by DNA cytofluorometry, Hoechst33258 staining when treated with paclitaxel for 48 hours. Meanwhile, Cell cycle and apoptotic rate were analyzed by flow cytometry. The protein expressions of Bax and Bcl-2 were studied by Western Blot. Results： Paclitaxel inhibited the proliferation of A549 cells in a time-and dose-dependant manner. Hoechst33258 staining indicated that apoptosis was induced by paclitaxel. After treated for 48 hours, cell apoptosis rates of 25 nmo1/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 11.52 ± 1.94% ,17.73 ±2.53%, and 29.32 ±5.51% respectively, which were significantly higher than those of control group 5.88 ±1.07%（all P 〈 0.01 ）, and apoptosis rate increased in dose-dependant manner. Meanwhile, G2/M stage cell percentage of 25 nmol/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 42.52 ± 6.25%, 40.46 ± 5.81%, and 35.34 ±6.17% respectively,which were significantly higher than that of control group 22.32 ± 3.30%（all P 〈 0.01 ）; Western blot showed that paclitaxel increased the expression of Bax and decreased the expression of Bcl-2 in dose-dependant manner. Conclusion： Paclitaxel can inhibit A549 cell proliferation in a time-and dose-dependant manner. Its mechanism may be related to arresting cell cycle in G2/M stage and induce cell apoptosis by up-modulating Bax expression and down-modulating Bcl-2 expression.展开更多
Lung cancer is one of the serious threats to human health and life of malignant diseases, on a global scale; it has become one of the major lung cancer deaths. Due to the growth of the tumor and the main reason is tha...Lung cancer is one of the serious threats to human health and life of malignant diseases, on a global scale; it has become one of the major lung cancer deaths. Due to the growth of the tumor and the main reason is that apoptosis is inhibited, therefore, it can induce apoptosis in lung cancer cells that is an important measure for the treatment of lung cancer, which is one of the effective means to reduce lung cancer mortality. In this paper, A549 human lung adenocarcinoma cell line, for example, has the use of chemical genetics of these emerging technological platforms, research pravastatin on apoptosis in human lung adenocarcinoma A549 intervention, while providing a theoretical basis for the development of new lung cancer therapy.展开更多
Background Survivin, a member of the inhibitor of apoptosis protein （IAP） family, overexpresses in tumor cells and not expresses in terminally differentiated adult tissues. This study aimed to investigate the effect...Background Survivin, a member of the inhibitor of apoptosis protein （IAP） family, overexpresses in tumor cells and not expresses in terminally differentiated adult tissues. This study aimed to investigate the effects of survivin-specific siRNA on cell proliferation, apoptosis and chemosensitivity to cisplatin in vitro and in vivo and explore the mechanisms about decreasing expression of survivin in reversing cancer cells resistance to chemotherapeutic drug.Methods Survivin-specific siRNA was transfected into A549/DDP cells. The expression of survivin and lung resistance-related protein （LRP） mRNA levels were determined by RT-PCR, chemosensitivity of A549/DDP （cisplatin）cells to cisplatin was determined by MTT assay, and apoptosis and cell cycle were determined by flow cytometry （FCM）.The protein expression levels of survivin, LRP, cyclin-D1, caspase-3 and bcl-2 were determined by Western blotting analyses. The effect of survivin siRNA inhibition on tumor growth was studied in athymic nude mice in vivo.Results Survivin-specific siRNA efficiently down-regulated survivin expression. The cell cycle was arrested at G2/M phase, and apoptosis was obviously found. Inhibition of survivin expression could make the IC50 and drug-resistant index of cisplatin decrease, and enhance the cancer cells sensitivity to cisplatin. After transfection by survivin-specific siRNA, expression of LRP and cyclin-D1 were downregulated, caspase-3 expression was upregulated, bcl-2 expression had no obvious change. The animal experiment confirmed knockdown of survivin could inhibit the tumor growth.Conclusions Survivin-specific siRNA can efficiently suppress the expression of survivin, increase apoptosis, inhibit cells proliferation and enhance the chemosensitivity to cisplatin in vitro and in vivo. Suppression of survivin expression helping to reverse drug-resistance may have relationship with downregulation of LRP and upregulation of caspase-3.Anti-tumor strategies based on the inhibition of survivin may be useful in targeting lung adenocarcinomas.展开更多
According to the fact that CEA gene expressed only in lung adenocarcinoma but not in normal lung cells, a retroviral expression vector (pCEATK) of the herpes simplex virus thymidine kinase (HSV-TK) gene regulated by C...According to the fact that CEA gene expressed only in lung adenocarcinoma but not in normal lung cells, a retroviral expression vector (pCEATK) of the herpes simplex virus thymidine kinase (HSV-TK) gene regulated by CEA promoter was constructed and introduced into CEA-producing human lung adenocarcinoma cells GL and non-CEA-producing HeLa cells. The expression of pCEATK and Ganciclovir (GCV) sensitivity of the transfected cells were tested in vitro and in vivo . pCEATK expressed only in CEA-producing GL cells but not in non-CEA-producing HeLa cells. The sensitivity to GCV of pCEATK-transfected GL was 992 times higher compared with that of the parental cell line and there was obvious 'bystander effect' in vitro. HeLa cells transfected wtih pCEATK were still resistant to GCV. Injection of GCV resulted in significant regression of pCEATK-transfected GL tumors in nude mice. In addition, all mice with any fraction of GL cells expressing HSV-TK exhibited a significant reduction in tumor growth, including mice with only 10% of GL cells expressing HSV-TK. These results show the possibility of HSV-TK gene-drug therapy using the tumor-specific promoter of CEA gene against CEA-producing lung cancers which was usually refractory to conventional chemotherapy.展开更多
In order to investigate the inhibitory effects of Endostar(rh-endostatin,YH-16)in combination with radiotherapy on lung adenocarcinoma A549 in mice and the interaction mechanisms of combined therapy,the transplantatio...In order to investigate the inhibitory effects of Endostar(rh-endostatin,YH-16)in combination with radiotherapy on lung adenocarcinoma A549 in mice and the interaction mechanisms of combined therapy,the transplantation tumor models of A549 lung adenocarcinoma were established.When the largest diameter of tumor reached 1.0cm,all nude mice were randomly divided into 4 groups:Endostar group,radiotherapy group,radiotherapy plus Endostar(combined treatment)group,and control group(n=6 in each group).The largest d...展开更多
Although there is an accumulating appreciation of the key roles that long intergenic non-coding RNAs （lincRNAs） play in diverse cellular processes, our knowledge of how lincRNAs function in cancer remains sparse. He...Although there is an accumulating appreciation of the key roles that long intergenic non-coding RNAs （lincRNAs） play in diverse cellular processes, our knowledge of how lincRNAs function in cancer remains sparse. Here, we present a comprehensive landscape of RNA-seq transcriptome profiles of lung adenocarcinomas and their paired normal counterparts to unravel gene regulation rules of lincRNAs. Consistent with previous findings of co-expression between neighboring protein-coding genes, lincRNAs were typically co-expressed with their neighboring genes, which was found in both cancerous and normal tissues. By building a mathematical model based on correlated gene expression, we distinguished an additional subset of lincRNAs termed ＂regulatory lincRNAs＂, representing their dominant roles in gene regulation. The number of regulatory lincRNAs was significantly higher in cancerous compared to normal tissues, and most of them positively regulated protein-coding genes in trans. Functional validation, using knockdown, determined that regulatory lincRNA, GASS, affected its predicted protein-coding targets. Moreover, we discovered hundreds of differentially expressed regulatory lincRNAs with inclusion of some cancer-associated lincRNAs. Our integrated analysis reveals enhanced regulatory effects of lincRNAs and provides a resource for the study of regulatory lincRNAs that play critical roles in lung adenocarcinoma.展开更多
文摘Objective： To investigate the effect of paclitaxel on cell proliferation and apoptosis of human lung adenocarcinoma A549 cells line and its mechanism in vitro. Methods ： Cell growth inhibition of paclitaxel on A549 cells was analyzed by MTT assay. Cell apoptosis was detected by DNA cytofluorometry, Hoechst33258 staining when treated with paclitaxel for 48 hours. Meanwhile, Cell cycle and apoptotic rate were analyzed by flow cytometry. The protein expressions of Bax and Bcl-2 were studied by Western Blot. Results： Paclitaxel inhibited the proliferation of A549 cells in a time-and dose-dependant manner. Hoechst33258 staining indicated that apoptosis was induced by paclitaxel. After treated for 48 hours, cell apoptosis rates of 25 nmo1/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 11.52 ± 1.94% ,17.73 ±2.53%, and 29.32 ±5.51% respectively, which were significantly higher than those of control group 5.88 ±1.07%（all P 〈 0.01 ）, and apoptosis rate increased in dose-dependant manner. Meanwhile, G2/M stage cell percentage of 25 nmol/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 42.52 ± 6.25%, 40.46 ± 5.81%, and 35.34 ±6.17% respectively,which were significantly higher than that of control group 22.32 ± 3.30%（all P 〈 0.01 ）; Western blot showed that paclitaxel increased the expression of Bax and decreased the expression of Bcl-2 in dose-dependant manner. Conclusion： Paclitaxel can inhibit A549 cell proliferation in a time-and dose-dependant manner. Its mechanism may be related to arresting cell cycle in G2/M stage and induce cell apoptosis by up-modulating Bax expression and down-modulating Bcl-2 expression.
文摘Lung cancer is one of the serious threats to human health and life of malignant diseases, on a global scale; it has become one of the major lung cancer deaths. Due to the growth of the tumor and the main reason is that apoptosis is inhibited, therefore, it can induce apoptosis in lung cancer cells that is an important measure for the treatment of lung cancer, which is one of the effective means to reduce lung cancer mortality. In this paper, A549 human lung adenocarcinoma cell line, for example, has the use of chemical genetics of these emerging technological platforms, research pravastatin on apoptosis in human lung adenocarcinoma A549 intervention, while providing a theoretical basis for the development of new lung cancer therapy.
文摘Background Survivin, a member of the inhibitor of apoptosis protein （IAP） family, overexpresses in tumor cells and not expresses in terminally differentiated adult tissues. This study aimed to investigate the effects of survivin-specific siRNA on cell proliferation, apoptosis and chemosensitivity to cisplatin in vitro and in vivo and explore the mechanisms about decreasing expression of survivin in reversing cancer cells resistance to chemotherapeutic drug.Methods Survivin-specific siRNA was transfected into A549/DDP cells. The expression of survivin and lung resistance-related protein （LRP） mRNA levels were determined by RT-PCR, chemosensitivity of A549/DDP （cisplatin）cells to cisplatin was determined by MTT assay, and apoptosis and cell cycle were determined by flow cytometry （FCM）.The protein expression levels of survivin, LRP, cyclin-D1, caspase-3 and bcl-2 were determined by Western blotting analyses. The effect of survivin siRNA inhibition on tumor growth was studied in athymic nude mice in vivo.Results Survivin-specific siRNA efficiently down-regulated survivin expression. The cell cycle was arrested at G2/M phase, and apoptosis was obviously found. Inhibition of survivin expression could make the IC50 and drug-resistant index of cisplatin decrease, and enhance the cancer cells sensitivity to cisplatin. After transfection by survivin-specific siRNA, expression of LRP and cyclin-D1 were downregulated, caspase-3 expression was upregulated, bcl-2 expression had no obvious change. The animal experiment confirmed knockdown of survivin could inhibit the tumor growth.Conclusions Survivin-specific siRNA can efficiently suppress the expression of survivin, increase apoptosis, inhibit cells proliferation and enhance the chemosensitivity to cisplatin in vitro and in vivo. Suppression of survivin expression helping to reverse drug-resistance may have relationship with downregulation of LRP and upregulation of caspase-3.Anti-tumor strategies based on the inhibition of survivin may be useful in targeting lung adenocarcinomas.
文摘According to the fact that CEA gene expressed only in lung adenocarcinoma but not in normal lung cells, a retroviral expression vector (pCEATK) of the herpes simplex virus thymidine kinase (HSV-TK) gene regulated by CEA promoter was constructed and introduced into CEA-producing human lung adenocarcinoma cells GL and non-CEA-producing HeLa cells. The expression of pCEATK and Ganciclovir (GCV) sensitivity of the transfected cells were tested in vitro and in vivo . pCEATK expressed only in CEA-producing GL cells but not in non-CEA-producing HeLa cells. The sensitivity to GCV of pCEATK-transfected GL was 992 times higher compared with that of the parental cell line and there was obvious 'bystander effect' in vitro. HeLa cells transfected wtih pCEATK were still resistant to GCV. Injection of GCV resulted in significant regression of pCEATK-transfected GL tumors in nude mice. In addition, all mice with any fraction of GL cells expressing HSV-TK exhibited a significant reduction in tumor growth, including mice with only 10% of GL cells expressing HSV-TK. These results show the possibility of HSV-TK gene-drug therapy using the tumor-specific promoter of CEA gene against CEA-producing lung cancers which was usually refractory to conventional chemotherapy.
文摘In order to investigate the inhibitory effects of Endostar(rh-endostatin,YH-16)in combination with radiotherapy on lung adenocarcinoma A549 in mice and the interaction mechanisms of combined therapy,the transplantation tumor models of A549 lung adenocarcinoma were established.When the largest diameter of tumor reached 1.0cm,all nude mice were randomly divided into 4 groups:Endostar group,radiotherapy group,radiotherapy plus Endostar(combined treatment)group,and control group(n=6 in each group).The largest d...
基金supported by the National Basic Research Program of China (No. 2011CB510100)the National Natural Science Foundation of China (No. 81030015)
文摘Although there is an accumulating appreciation of the key roles that long intergenic non-coding RNAs （lincRNAs） play in diverse cellular processes, our knowledge of how lincRNAs function in cancer remains sparse. Here, we present a comprehensive landscape of RNA-seq transcriptome profiles of lung adenocarcinomas and their paired normal counterparts to unravel gene regulation rules of lincRNAs. Consistent with previous findings of co-expression between neighboring protein-coding genes, lincRNAs were typically co-expressed with their neighboring genes, which was found in both cancerous and normal tissues. By building a mathematical model based on correlated gene expression, we distinguished an additional subset of lincRNAs termed ＂regulatory lincRNAs＂, representing their dominant roles in gene regulation. The number of regulatory lincRNAs was significantly higher in cancerous compared to normal tissues, and most of them positively regulated protein-coding genes in trans. Functional validation, using knockdown, determined that regulatory lincRNA, GASS, affected its predicted protein-coding targets. Moreover, we discovered hundreds of differentially expressed regulatory lincRNAs with inclusion of some cancer-associated lincRNAs. Our integrated analysis reveals enhanced regulatory effects of lincRNAs and provides a resource for the study of regulatory lincRNAs that play critical roles in lung adenocarcinoma.
