人质膜型唾液酸酶在前列腺癌细胞凋亡中的作用

Effects of human membrane associated sialidase on apoptosis of PC3 cells

目的:探讨人质膜型唾液酸酶(NEU3)在维生素K3(VK3)诱导的人雄激素非依赖型前列腺癌PC3细胞凋亡中的作用及可能机制。方法:以稳定转染人质膜型唾液酸酶基因(neu3)的前列腺癌细胞(PC3-neu3细胞)为靶细胞,通过MTT、吖啶橙/溴化乙啶(AO/EB)染色观察VK3作用下NEU3与凋亡的关系;应用细胞内活性氧(ROS)测定,Western blotting检测p65、Bcl-XL蛋白表达,探讨NEU3影响细胞凋亡的机制。结果:(1)VK3浓度相同时,PC3-neu3细胞的生存率高于PC3细胞,凋亡率低于PC3细胞;PC3-neu3细胞内ROS产生的荧光强度弱于PC3细胞。(2)在VK3的作用下,p65的蛋白表达在两组细胞中具有相同的趋势,均随VK3浓度的增加,蛋白表达增强;Bcl-XL的蛋白表达趋势则相反,PC3细胞组,Bcl-XL的表达随VK3浓度的增加逐渐减弱,而PC3-neu3细胞组则增强,两组比较差异显著(P<0.01)。结论:NEU3对VK3诱导的细胞凋亡具有抵抗作用,这一作用是通过降低细胞内活性氧水平,上调Bcl-XL和p65的蛋白表达实现的。

AIM： To explore the effects and mechanisms of human membrane associated sialidase （NEU3） on apoptosis of PC3 cells induced by vitamin K3 （VK3）. METHODS： The target cells was PC3 cells stable transfected the gene of NEU3 （neu3）. The relation of NEU3 and apoptosis was detected by MTT assay and AO/EB - staining. The mechanisms were investigated by examining intracellular ROS and p65, Bcl - XL protein expression. RESULTS ： （ 1 ） The survival rate of PC3 - neu3 cells were higher than that of PC3 cells under the condition of the same VK3 density. The apoptosis rate of PC3 - neu3 cells was lower, and the fluorescence intensity of ROS in PC3 - neu3 cells was weaker than that in PC3 cells. （2） The expression tendency of p65 was the same in the two groups treated by VK3. The density of VK3 was increased, the protein expression was stronger. With the density of VK3 increased, the Bcl - XL protein expression was weaker in PC3 cells and it was stronger in PC3 - neu3 cells （P 〈 0. 01 ）. CONCLUSION： The antiapoptotic mechanisms of NEU3 may be related with the suppressed intra - cellar ROS synthesis, upregulation of p65 and Bcl - XL expression.