蛋白激酶C亚型在鼻咽癌细胞中的分布及在增殖中的作用

Distribution of subtypes of protein kinase C in nasopharyngeal carcinoma cell line and their roles in cell proliferation

本文检测了人低分化鼻咽癌上皮细胞系（ＣＮＥ－２Ｚ）颗粒部分与胞浆部分ＰＫＣ的三种主要亚型的含量和分布。结果发现：（１）ＣＮＥ－２Ｚ细胞的颗粒部分中ＰＫＣ－Ⅱ型相对较少，而ＰＫＣ－Ⅰ，Ⅲ型则相对较多；（２）随ＴＰＡ浓度增大，ＰＫＣ总量及颗粒部分的ＰＫＣ－Ⅲ下降明显，细胞的生长也受抑制，１０－６ｍｏｌ／Ｌ时，ＰＫＣ－Ⅲ仅为对照的３５．６％，抑制率达６０％；（３）随ＴＰＡ作用时间延长，ＰＫＣ总量及颗粒部分的ＰＫＣ－Ⅲ下降明显，ＰＫＣ－Ⅲ的变化自１５ｍｉｎ时开始，１２０ｍｉｎ时仅为对照的１８．６％；在１３ｈ后，细胞增殖出现抑制，２６ｈ抑制率达５５％。结果提示，ＰＫＣ在ＣＮＥ－２Ｚ细胞中以Ⅰ，Ⅲ型含量较多，尤其ＰＫＣ－Ⅲ对生长起重要作用。

The content of three PKC subtypes in particulate and cytosolic fractions of the poorly differentiated human nasopharynyeal carcinoma epithelial cell line (CNE-2Z)was determined and the change of PKC subtypes and the growth of CNE-2Z cells by treatment with 12-o-tetra-decanoylphorbol-13-acetate(TPA) were observed.Results showed that (1) In the particulate fraction of CNE-2Z cells,the content of typeⅠ,Ⅲ was distinctly higher than type Ⅱ;(2) At 30 min after CNE-2Z cells were cultured with various concentrations of TPA,total PKC and type Ⅲ in particulate fraction fell along with the increase of TPA concentrations.PKC-Ⅲ of particulate fraction decreased to 35.6% and cell growth was inhibited by 60% at 10-6mol/L of TPA;(3) When CNE-2Z cells were treated with TPA(10-6 mol/L) in different time,the contents of PKC subtypes,especial in type Ⅲ in particulate and also total PKC decreased.The decrease in PKC Ⅲ in particulate was apparent as early as 15 min,and was the most marked at 120 min,which was only 18.6% of the control group.After 13h of TPA treatment,cell growth started to be distinctly inhibited,and the strongest inhibition (55%) occured at 26h.Our findings indicated that content of type Ⅰ,Ⅲ PKC in CNE-2Z cells is high and PKC,especial type Ⅲ in particulate fraction was responsible for growth of CNE-2Z cell.