Eggens I, Ericsson J, Tollbom O
Department of Pathology, Huddinge Hospital, Karolinska Institutet.
Cancer Res. 1988 Jun 15;48(12):3418-24.
Homogenates and microsomal fractions prepared from biopsies of highly differentiated human hepatocellular carcinomas were found to contain low levels of dolichol in comparison with control tissue. In contrast, the amount of dolichyl phosphate in tumor homogenates was unchanged and actually increased in the microsomal fraction. The pattern of individual polyisoprenoids, both in the free and the phosphorylated dolichol fractions of hepatomas, did not exhibit any major alterations compared to the control. The rates of incorporation of [3H]mevalonic acid into dolichol and dolichyl phosphate in hepatomas were low. The dolichol monophosphatase activities in microsomal fractions from hepatomas and controls did not show any major differences, whereas the activity of the CTP-dependent dolichol kinase was increased in tumor microsomes. Glycosylation of endogenous dolichyl phosphate and of total protein using certain nucleotide-activated sugars was found to be slightly elevated in microsomal fractions from the tumor itself when compared to the control. The reasons for the differences in the levels of polyisoprenoids in hepatomas and control tissue are discussed.
与对照组织相比，从高分化人肝细胞癌活检组织制备的匀浆和微粒体组分中发现含有低水平的多萜醇。相比之下，肿瘤匀浆中磷酸多萜醇的量没有变化，而在微粒体组分中实际上有所增加。与对照相比，肝癌的游离和磷酸化多萜醇组分中各个聚异戊二烯的模式没有表现出任何重大改变。肝癌中[3H]甲羟戊酸掺入多萜醇和磷酸多萜醇的速率较低。肝癌和对照的微粒体组分中的多萜醇单磷酸酶活性没有显示出任何重大差异，而肿瘤微粒体中依赖CTP的多萜醇激酶的活性增加。与对照相比，当使用某些核苷酸活化糖时，肿瘤自身微粒体组分中内源性磷酸多萜醇和总蛋白的糖基化略有升高。讨论了肝癌和对照组织中聚异戊二烯水平差异的原因。
