AIM: To investigate the effect of telomerase hTERT gene antisense oligonucleotide (hTERT-ASO) on proliferation and telomerase activity of pancreatic cancer cell line Bxpc-3. METHODS: MTT assay was used to detect t...AIM: To investigate the effect of telomerase hTERT gene antisense oligonucleotide (hTERT-ASO) on proliferation and telomerase activity of pancreatic cancer cell line Bxpc-3. METHODS: MTT assay was used to detect the effect of different doses of hTERT-ASO on proliferation of Bxpc-3 cell for different times. To study the anti-tumor activity, the cells were divided into there groups: Control group (pancreatic cancer cell Bxpc-3); antisense oligonucleotide (hTERT-ASO) group; and nosense oligonucleotide group decorated with phosphorothioate. Telomerase activity was detected using TRAP-PCR-ELISA. Cell DNA distribution was examined using flow cytometry assay. Cell apoptosis was observed by transmission electron microscope in each group. RESULTS: After treatment with 6 mmollL hTERT- ASO, cell proliferation was inhibited in dose- and time- dependent manner. The telomerase activity decreased after treatment with hTERT-ASO for 72 h. Flow cytometry showed the cell number of G0/G1 phase increased from 2.7% to 14.7%, the cell number of S phase decreased from 72.7% to 51.0%, and a sub-G1 stage cell apoptosis peak appeared in front of G1 stage. CONCLUSION: Telomerase antisense oligodeoxy- nucleotide can inhibit the proliferation of pancreatic cancer cell line Bxpc-3 and decrease the telomerase activity and increase cell apoptosis rate in vitro.展开更多
K-ras is a member of ras gene family which is involved in cell survival,proliferation and differentiation.When a mutation occurs in ras gene,the activation of Ras proteins may be prolonged to induce oncogenesis.Howeve...K-ras is a member of ras gene family which is involved in cell survival,proliferation and differentiation.When a mutation occurs in ras gene,the activation of Ras proteins may be prolonged to induce oncogenesis.However,the relationship between K-ras mutation and clinical outcomes in pancreatic cancer patients treated with chemotherapy agents is still under debate.In this study,we constructed five pAcGFP1-C3 plasmids for different types of K-ras gene(WT,G12V,G12R,G12D,and G13D)and stably transfected human pancreatic cancer Bxpc-3 cells with these genes.The wild type and mutant clones showed a comparable growth and expression of K-Ras-GFP fusion protein.The expression of some K-ras mutations resulted in a reduced sensitivity to gefitinib,5-FU,docetaxel and gemcitabine,while showed no effects on erlotinib or cisplatin.Moreover,compared with the wild type clone,K-Ras downstream signals(phospho-Akt and/or phospho-Erk)were increased in K-ras mutant clones.Interestingly,different types of K-ras mutation had non-identical K-Ras downstream signal activities and drug responses.Our results are the first to reveal the relationship between different K-ras mutation and drug sensitivities of these anti-cancer drugs in pancreatic cancer cells in vitro.展开更多
文摘AIM: To investigate the effect of telomerase hTERT gene antisense oligonucleotide (hTERT-ASO) on proliferation and telomerase activity of pancreatic cancer cell line Bxpc-3. METHODS: MTT assay was used to detect the effect of different doses of hTERT-ASO on proliferation of Bxpc-3 cell for different times. To study the anti-tumor activity, the cells were divided into there groups: Control group (pancreatic cancer cell Bxpc-3); antisense oligonucleotide (hTERT-ASO) group; and nosense oligonucleotide group decorated with phosphorothioate. Telomerase activity was detected using TRAP-PCR-ELISA. Cell DNA distribution was examined using flow cytometry assay. Cell apoptosis was observed by transmission electron microscope in each group. RESULTS: After treatment with 6 mmollL hTERT- ASO, cell proliferation was inhibited in dose- and time- dependent manner. The telomerase activity decreased after treatment with hTERT-ASO for 72 h. Flow cytometry showed the cell number of G0/G1 phase increased from 2.7% to 14.7%, the cell number of S phase decreased from 72.7% to 51.0%, and a sub-G1 stage cell apoptosis peak appeared in front of G1 stage. CONCLUSION: Telomerase antisense oligodeoxy- nucleotide can inhibit the proliferation of pancreatic cancer cell line Bxpc-3 and decrease the telomerase activity and increase cell apoptosis rate in vitro.
基金supported by National Natural Science Foundation of China(81102459)the Fundamental Research Funds for the Central Universities,Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(Guangxi Normal University)+1 种基金Ministry of Education of China(CMEMR2012-B07)Doctoral Fund of Ministry of Education of China(20130071110069)
文摘K-ras is a member of ras gene family which is involved in cell survival,proliferation and differentiation.When a mutation occurs in ras gene,the activation of Ras proteins may be prolonged to induce oncogenesis.However,the relationship between K-ras mutation and clinical outcomes in pancreatic cancer patients treated with chemotherapy agents is still under debate.In this study,we constructed five pAcGFP1-C3 plasmids for different types of K-ras gene(WT,G12V,G12R,G12D,and G13D)and stably transfected human pancreatic cancer Bxpc-3 cells with these genes.The wild type and mutant clones showed a comparable growth and expression of K-Ras-GFP fusion protein.The expression of some K-ras mutations resulted in a reduced sensitivity to gefitinib,5-FU,docetaxel and gemcitabine,while showed no effects on erlotinib or cisplatin.Moreover,compared with the wild type clone,K-Ras downstream signals(phospho-Akt and/or phospho-Erk)were increased in K-ras mutant clones.Interestingly,different types of K-ras mutation had non-identical K-Ras downstream signal activities and drug responses.Our results are the first to reveal the relationship between different K-ras mutation and drug sensitivities of these anti-cancer drugs in pancreatic cancer cells in vitro.