Liang Libo, He He, Lv Ruixue, Zhang Mei, Huang Henjian, An Zhenmei, Li Shuangqing
West China Hospital of Sichuan University, Chengdu, People's Republic of China,
Tumour Biol. 2015 Feb;36(2):1245-50. doi: 10.1007/s13277-014-2750-y. Epub 2014 Oct 26.
Wnt/β-catenin signaling pathway, having a crucial role in regulating diverse cellular processes, can be a new therapeutic target in cancer. To investigate the role of Dkk-1 (Dickkopf-1) and Dkk-3 in tumors and cirrhoses of the liver tissue in hepatocellular carcinoma (HCC), tissues from 38 patients with HCC resections including 5 patients who underwent hemangioma surgery of adjacent tumor tissues at the same time were obtained. Tissues were divided into three groups (nonfibrosis, cirrhosis, and carcinoma) through hematoxylin-eosin (HE) staining. Methylation-specific polymerase chain reaction (PCR) (MSP) measured the methylation status, and reverse transcription-PCR tested the messenger RNA (mRNA) levels, and immunohistochemical analysis provided levels of protein expression. The methylation detection rate of Dkk-1 and Dkk-3 was the highest (P < 0.05) and the mRNA levels of Dkk-1 and Dkk-3 were the lowest (P < 0.05) in the carcinoma tissues. The mRNA levels of β-catenin were significantly higher in the carcinoma tissue than the other tissues (P < 0.05). The expression of Dkk-1 and Dkk-3 was significantly higher in the carcinoma tissues than the other tissues (P < 0.05); but the β-catenin expression was the highest (P < 0.05). Compared with the control, the mRNA levels of β-catenin in the Dkk-1 and Dkk-3 silencing cells increased 5.34 (P < 0.05) and 3.5 times (P > 0.05). After the interference of 5-aza-2'-deoxycytidine, the mRNA levels of Dkk-1 and Dkk-3 significantly increased 58.9 and 59.3 times (P < 0.0001), and the mRNA levels of β-catenin decreased 6.02 times (P < 0.05). In the process of HCC, the abnormal activity of Wnt/β-catenin signaling may be associated with the methylation of Dkk-1 and Dkk-3.
Wnt/β-连环蛋白信号通路在调节多种细胞过程中起关键作用，可能成为癌症治疗的新靶点。为研究Dickkopf-1（Dkk-1）和Dkk-3在肝细胞癌（HCC）肝组织肿瘤及肝硬化中的作用，获取了38例行HCC切除术患者的组织，其中5例同时接受了相邻肿瘤组织的血管瘤手术。通过苏木精-伊红（HE）染色将组织分为三组（无纤维化、肝硬化和癌）。甲基化特异性聚合酶链反应（PCR）（MSP）检测甲基化状态，逆转录PCR检测信使核糖核酸（mRNA）水平，免疫组织化学分析提供蛋白表达水平。癌组织中Dkk-1和Dkk-3的甲基化检测率最高（P < 0.05），Dkk-1和Dkk-3的mRNA水平最低（P < 0.05）。癌组织中β-连环蛋白的mRNA水平显著高于其他组织（P < 0.05）。癌组织中Dkk-1和Dkk-3的表达显著高于其他组织（P < 0.05）；但β-连环蛋白表达最高（P < 0.05）。与对照组相比，Dkk-1和Dkk-3沉默细胞中β-连环蛋白的mRNA水平分别增加了5.34倍（P < 0.05）和3.5倍（P > 0.05）。经5-氮杂-2'-脱氧胞苷干扰后，Dkk-1和Dkk-3的mRNA水平显著增加了58.9倍和59.3倍（P < 0.0001），β-连环蛋白的mRNA水平降低了6.02倍（P < 0.05）。在HCC发生过程中，Wnt/β-连环蛋白信号通路的异常激活可能与Dkk-1和Dkk-3的甲基化有关。
