【摘要】 目的:初步探讨过氧化还原蛋白1(peroxirodoxin 1,PRDX1)抑制蛋白酶体抑制剂诱导人甲状腺癌细胞凋亡的机制。方法:选取人甲状腺癌细胞,设立随机序列核酸siRNA、siASK1、siPRDX1和siASK1+siPRDX1组,分别用培养液、lactacystin和MG132培养细胞;用蛋白印迹法检测PRDX1、ASK1、p38、JNK1/2、p-ASK1、p-P38和p-JNK1/2在各组甲状腺癌细胞中的表达;用微小RNA干扰技术转染细胞;应用流式细胞仪检测细胞凋亡率。结果:MG132处理组中,p-ASK1是对照组的1.5倍(F=214.14,P<0.001),其下游效应子p-p38和p-JNK1/2分别为对照组的1.34(F=216.75,P<0.001)和1.94倍(F=1 601.68,P<0.001);siASK1下调MG132介导的p-ASK1为随机序列组的0.58倍(F=1 136.82,P<0.001),p-p38为随机序列组的0.73倍(F=507.00,P<0.001),p-JNK1/2为随机序列组的0.51倍(F=6 087.48,P<0.001)。甲状腺癌细胞凋亡率降低为34.25%,显著低于于随机序列组的51.98%,F=18.39,P=0.013。MG132处理组中,siPRDX1组甲状腺癌细胞凋亡率为68.99%显著高于随机序列组的49.58%和siPRDX1+siASK1联合组的41.28%,而siASK1组的甲状腺癌细胞凋亡率为31.85%,显著低于上述两组,组间差异有统计学意义,F=30.13,P<0.001。结论:PRDX1通过负向调节ASK1活性及ASK1-p38和ASK1-JNK通路,抑制ASK1介导的细胞凋亡进而消减MG132对甲状腺癌细胞毒性效应。更多还原

【Abstract】 OBJECTIVE:To investigate molecular mechanism of peroxiredoxins(PRDX1)in inhibiting apoptosis of thyroid cancer cells affected by proteasome inhibitor.METHODS:A panel of cancer cells were selected for the investigation,set up scramble siRNA,siASK1,siPRDX1,siASK1and siPRDX1,followed by treatment with vehicle control,MG132or lactacystin;the expression of PRDX1,ASK1,P38,JNK1/2,p-ASK1,p-P38,p-JNK1/2protein in each group of thyroid cancer cells was confirmed by Western blot,respectively.The small interfering RNA(siRNA)was transfected to thyroid cancer cells;flow cytometry was used to measure apoptotic cells.RESULTS:The protein expressions of p-ASK1,p-38and p-JNK1/2were significantly increased in MG132,1.5,1.34and 1.94times higher in MG132treated group compared to those in control group(F=214.14,F=216.75,F=1 601.68,all P<0.001).Compared with the groups treated with scramble,the expressions of p-ASK1in the MG132treated was also inhibited by 0.58times(F=1 136.82,P<0.001).The expressions of p-p38and p-JNK1/2were also suppressed by 0.73and 0.51times in the MG132treated(F=507.00,F=6 087.48,both P<0.001).The apoptosis rate of thyroid cancer cells in the MG132treated was 34.25% which was significantly lower than 51.98%(F=18.39,P=0.013)in scramble groups.Among the MG132groups,the apoptosis rate of the siPRDX1treated was 68.99%,obviously higher than those of the group treated with scramble(49.58%)and the group treated with siPRDX1+siASK1(41.28%);but for the siASK1treated,the apoptotic rate was 31.85%,which was significantly lower than those of the two groups(F=30.13,P<0.001).CONCLUSION:PRDX1can inhibit apoptosis and attenuat the cytotoxic effect of thyroid cancer cells induced by MG132via negatively regulating the ativity of ASK1and the pathways of ASK1-p38and ASK1-JNK.更多还原