目的:探讨甲基化酶抑制剂5'-氮杂-2'-脱氧胞苷(5'-Aza-2'-deoxycytidine,5'-Aza-CdR)对结直肠癌细胞株HT-29和LoVo中CDX2基因甲基化水平、mRNA及蛋白表达的影响.方法:用不同浓度5'-Aza-CdR处理结直肠癌细胞株HT...目的:探讨甲基化酶抑制剂5'-氮杂-2'-脱氧胞苷(5'-Aza-2'-deoxycytidine,5'-Aza-CdR)对结直肠癌细胞株HT-29和LoVo中CDX2基因甲基化水平、mRNA及蛋白表达的影响.方法:用不同浓度5'-Aza-CdR处理结直肠癌细胞株HT-29和LoVo.应用TaqMan探针为基础的实时定量PCR(Methylight)方法、SYBR Green PCR方法及蛋白印迹实验(Western blot)检测药物处理前后HT-29和LoVo细胞中CDX2基因的甲基化状态、mRNA和蛋白表达.结果:Methylight检测HT-29和LoVo细胞中C D X2蛋白在药物作用异常甲基化未得到逆转;实时荧光定量PCR和Western blot检测到0.5、1.0、1.5μmol/L 5'-Aza-CdR处理后C D X2基因m R N A和蛋白重新表达,实时荧光定量PCR检测对照组和不同浓度实验组在HT-29细胞株mRNA相对表达量分别为1.000±0.000、0.973±0.024、1.014±0.019和1.094±0.020;在LoVo细胞株相对表达量分别为1.000±0.000、0.966±0.038、1.050±0.029和1.007±0.019.Western blot检测CDX2蛋白在对照组和不同浓度实验组中HT-29细胞株相对表达量分别为0.454±0.049、0.501±0.041、0.340±0.050和0.531±0.046;LoVo细胞株相对表达量分别为0.527±0.037、0.415±0.037、0.432±0.040和0.626±0.046.以上作用无时间、剂量依赖性,但CDX2基因mRNA在HT-29细胞株表达(F=25.146,P=0.000)和LoVo细胞株表达(F=5.470,P=0.024)具有统计学差异,C D X2蛋白表达在HT-29细胞株表达(F=9.700,P=0.005)和LoVo细胞株表达(F=17.701,P=0.001)亦具有统计学差异.结论:结直肠癌细胞株HT-29和LoVo中CDX2基因mRNA和蛋白表达不受中DNA甲基化的表观遗传修饰的调控.展开更多
AIM： To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS： Two human colon cancer cell lines （HCT-15 and HT-29） were treated with 5-FU and celecoxib, alone and in...AIM： To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS： Two human colon cancer cell lines （HCT-15 and HT-29） were treated with 5-FU and celecoxib, alone and in combination. The effects of each drug were evaluated using the MTT （3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide） assay, flow cytometry, and western blotting. RESULTS： 5-FU and celecoxib showed a dosedependent cytotoxic effect. When treated with 10-3 mol/L 5-FU （IC50） and celecoxib with its concentration ranging from 10.8 mol/L to 10.4 mol/L of celecoxib, cells showed reduced cytotoxic effect than 5-FU （10.3 mol/L） alone. Flow cytometry showed that celecoxib attenuated 5-FU induced accumulation of cells at subG1 phase. Western blot analyses for caspase-3 and poly （ADP-ribose） polymerase （PARP） cleavage showed that celecoxib attenuated 5-FU induced apoptosis. Western blot analyses for cell cycle molecules showed that G2/M arrest might be possible cause of 5-FU induced apoptosis and celecoxib attenuated 5-FU induced apoptosis via blocking of cell cycle progression to the G2/M phase, causing an accumulation of cells at the GI/S phase. CONCLUSION： We found that celecoxib attenuated cytotoxic effect of 5-FU. Celecoxib might act via inhibition of cell cycle progression, thus preventing apoptosis induced by 5-FU.展开更多
Multinucleax solid-state NMR was employed to study the silicon-substitutedmolecular sieve Si-VPI-5. 29Si and 27Al NMR suggest that Si can be incorporated intothe framework of VPI-5 and the substitution of two silicon ...Multinucleax solid-state NMR was employed to study the silicon-substitutedmolecular sieve Si-VPI-5. 29Si and 27Al NMR suggest that Si can be incorporated intothe framework of VPI-5 and the substitution of two silicon atoms for an aluminium atomplus a phosphorus atom is predominant. Such substitution is limited in a certain domainof the crystal and "silicon rich" regions are thus generated. 1H MAS spectra reveal that asmall arnount of silicon atoms substitute phosphorus only and SiOHAl groups are formed,which provides the acidic source for the molecular sieves. Si-VPI-5 prepared with silicagel as the silicon source exhibits a higher content of SiOHAl groups than that preparedwith (EtO)4Si.展开更多
文摘目的:探讨甲基化酶抑制剂5'-氮杂-2'-脱氧胞苷(5'-Aza-2'-deoxycytidine,5'-Aza-CdR)对结直肠癌细胞株HT-29和LoVo中CDX2基因甲基化水平、mRNA及蛋白表达的影响.方法:用不同浓度5'-Aza-CdR处理结直肠癌细胞株HT-29和LoVo.应用TaqMan探针为基础的实时定量PCR(Methylight)方法、SYBR Green PCR方法及蛋白印迹实验(Western blot)检测药物处理前后HT-29和LoVo细胞中CDX2基因的甲基化状态、mRNA和蛋白表达.结果:Methylight检测HT-29和LoVo细胞中C D X2蛋白在药物作用异常甲基化未得到逆转;实时荧光定量PCR和Western blot检测到0.5、1.0、1.5μmol/L 5'-Aza-CdR处理后C D X2基因m R N A和蛋白重新表达,实时荧光定量PCR检测对照组和不同浓度实验组在HT-29细胞株mRNA相对表达量分别为1.000±0.000、0.973±0.024、1.014±0.019和1.094±0.020;在LoVo细胞株相对表达量分别为1.000±0.000、0.966±0.038、1.050±0.029和1.007±0.019.Western blot检测CDX2蛋白在对照组和不同浓度实验组中HT-29细胞株相对表达量分别为0.454±0.049、0.501±0.041、0.340±0.050和0.531±0.046;LoVo细胞株相对表达量分别为0.527±0.037、0.415±0.037、0.432±0.040和0.626±0.046.以上作用无时间、剂量依赖性,但CDX2基因mRNA在HT-29细胞株表达(F=25.146,P=0.000)和LoVo细胞株表达(F=5.470,P=0.024)具有统计学差异,C D X2蛋白表达在HT-29细胞株表达(F=9.700,P=0.005)和LoVo细胞株表达(F=17.701,P=0.001)亦具有统计学差异.结论:结直肠癌细胞株HT-29和LoVo中CDX2基因mRNA和蛋白表达不受中DNA甲基化的表观遗传修饰的调控.
文摘AIM： To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS： Two human colon cancer cell lines （HCT-15 and HT-29） were treated with 5-FU and celecoxib, alone and in combination. The effects of each drug were evaluated using the MTT （3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide） assay, flow cytometry, and western blotting. RESULTS： 5-FU and celecoxib showed a dosedependent cytotoxic effect. When treated with 10-3 mol/L 5-FU （IC50） and celecoxib with its concentration ranging from 10.8 mol/L to 10.4 mol/L of celecoxib, cells showed reduced cytotoxic effect than 5-FU （10.3 mol/L） alone. Flow cytometry showed that celecoxib attenuated 5-FU induced accumulation of cells at subG1 phase. Western blot analyses for caspase-3 and poly （ADP-ribose） polymerase （PARP） cleavage showed that celecoxib attenuated 5-FU induced apoptosis. Western blot analyses for cell cycle molecules showed that G2/M arrest might be possible cause of 5-FU induced apoptosis and celecoxib attenuated 5-FU induced apoptosis via blocking of cell cycle progression to the G2/M phase, causing an accumulation of cells at the GI/S phase. CONCLUSION： We found that celecoxib attenuated cytotoxic effect of 5-FU. Celecoxib might act via inhibition of cell cycle progression, thus preventing apoptosis induced by 5-FU.
文摘Multinucleax solid-state NMR was employed to study the silicon-substitutedmolecular sieve Si-VPI-5. 29Si and 27Al NMR suggest that Si can be incorporated intothe framework of VPI-5 and the substitution of two silicon atoms for an aluminium atomplus a phosphorus atom is predominant. Such substitution is limited in a certain domainof the crystal and "silicon rich" regions are thus generated. 1H MAS spectra reveal that asmall arnount of silicon atoms substitute phosphorus only and SiOHAl groups are formed,which provides the acidic source for the molecular sieves. Si-VPI-5 prepared with silicagel as the silicon source exhibits a higher content of SiOHAl groups than that preparedwith (EtO)4Si.
