sonic hedgehog 信号通路在肝癌中的表达及其在体外通过下调 Bcl-2 诱导的 cyclopamine 诱导的细胞凋亡。

Expression of sonic hedgehog signaling components in hepatocellular carcinoma and cyclopamine-induced apoptosis through Bcl-2 downregulation in vitro.

机构信息

Department of Hepatobiliary Surgery, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.

出版信息

Arch Med Res. 2010 Jul;41(5):315-23. doi: 10.1016/j.arcmed.2010.06.003.

DOI:10.1016/j.arcmed.2010.06.003

PMID:20851287

Abstract

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Aberrant activation of sonic hedgehog (Shh) signaling pathway plays important roles in tumorigenesis and progression of several tumors. Cyclopamine, an important inhibitor of Shh signaling pathway, can induce cell apoptosis. However, the mechanisms underlying cyclopamine-induced apoptosis are not well understood. The aim of this study is to determine the expression of the Shh signaling pathway components in HCC and to investigate the mechanisms underlying cyclopamine-induced apoptosis in HCC cells.

METHODS

Shh signaling components (Shh, Ptch, Smo and Gli-1) expression levels were evaluated by immunohistochemistry on tissue microarrays containing 98 HCCs with paired adjacent noncancerous liver tissues. The relationships between sonic hedgehog signal pathway and clinicopathological factors were analyzed in HCC. Cell viability was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was detected by flow cytometry. mRNA and protein levels were analyzed by RT-PCR and Western blot, respectively.

RESULTS

Shh, Ptch, Smo and Gli-1 were overexpressed in HCC tissues compared with paired adjacent noncancerous liver tissue. Activated Shh signaling pathway was associated with tumor size, capsular invasion and vascular invasion in HCC. Cyclopamine remarkably decreased cell viability, induced apoptosis and downregulated Bcl-2 expression in HCC cells.

CONCLUSIONS

Shh signaling pathway plays an important role in HCC tumorigenesis and progression, indicating that Shh signaling pathway is a potential therapeutic target for HCC. Cyclopamine induces apoptosis through downregulating Bcl-2 in HCC.

摘要

背景与目的

肝细胞癌（HCC）是全球最常见的恶性肿瘤之一。 sonic hedgehog（Shh）信号通路的异常激活在几种肿瘤的发生和发展中起着重要作用。环巴胺是 Shh 信号通路的重要抑制剂，可诱导细胞凋亡。然而，环巴胺诱导凋亡的机制尚不清楚。本研究旨在确定 HCC 中 Shh 信号通路成分的表达，并探讨环巴胺诱导 HCC 细胞凋亡的机制。

方法

采用组织微阵列免疫组织化学法检测 98 例 HCC 及其配对癌旁正常肝组织中 Shh 信号通路成分（Shh、Ptch、Smo 和 Gli-1）的表达水平。分析 sonic hedgehog 信号通路与 HCC 临床病理因素的关系。通过 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）法分析细胞活力。通过流式细胞术检测细胞凋亡。通过 RT-PCR 和 Western blot 分别分析 mRNA 和蛋白水平。