ABSTRACT
BACKGROUND: Survivin has multiple functions during the progression of cancer. However, the role of survivin in the progression and metastasis of hepatocellular carcinoma (HCC) remains unknown. MATERIALS AND METHODS: Survivin expression in HCC cells (Mahlavu and Hep3B) was assessed using reverse transcription real-time PCR and Western blot analyses. In addition, survivin expression in HCC cells was manipulated using small interfering RNA (siRNA) or overexpression and proliferation and transwell migration assays were performed to monitor the effect of manipulated survivin expression on the growth rate and migratory ability of the transfected cells. RESULTS: Among the HCC cell lines tested, we found high endogenous expression of survivin mRNA and protein in Mahlavu cells. After silencing survivin expression in Mahlavu cells, there was a dramatic decrease in the cell growth rate and an increase in the metastatic potential of the cells. Overexpression of survivin in Hep3B cells suppressed the ability of the cell to migrate. The mechanism of enhanced cell migration caused by decreased survivin expression is mediated through the downregulation of glucose-regulated protein 78 (GRP78) and the upregulation of the epithelial-mesenchymal transition (EMT) marker, vimentin. CONCLUSIONS: Survivin may mediate metastasis in HCC. The knockdown of survivin expression may enhance cancer metastasis through the downregulation of GRP78 and upregulation of vimentin expression.
Subject(s)
Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Movement , Epithelial-Mesenchymal Transition , Heat-Shock Proteins/metabolism , Inhibitor of Apoptosis Proteins/metabolism , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Apoptosis , Blotting, Western , Carcinoma, Hepatocellular/genetics , Cell Adhesion , Cell Proliferation , Endoplasmic Reticulum Chaperone BiP , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Heat-Shock Proteins/antagonists & inhibitors , Heat-Shock Proteins/genetics , Humans , Immunoenzyme Techniques , Inhibitor of Apoptosis Proteins/antagonists & inhibitors , Inhibitor of Apoptosis Proteins/genetics , Liver Neoplasms/genetics , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Real-Time Polymerase Chain Reaction , Survivin , Tumor Cells, Cultured , Vimentin/genetics , Vimentin/metabolismABSTRACT
BACKGROUND: In this study, we intended to dissect the mechanism of 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-enhanced migration of gastric cancer. Smoking has been defined as a risk factor for gastric cancer. Tobacco-specific carcinogen, NNK, was reported to enhance cancer progression in gastric cancer. Currently, metastasis is the major issue for clinical cancer therapy, but the influence of NNK on the migration of gastric cancer remains to be determined. METHODS: The expression of nicotinic receptor in gastric cancer cells was identified by real-time polymerase chain reaction and Western blotting. The influence of NNK on migration of gastric cancer cells was evaluated by the transwell migration assay system. Receptor-mediated migration was studied by both inhibitor and small interfering RNA. RESULTS: Alpha7 nicotinic acetylcholine receptor, alpha7-nicotinic acetylcholine receptor (nAChR), was identified higher than alpha9-nAChR in gastric cancer cell lines, AGS cells. NNK enhanced significantly gastric cancer cell migration in transwell assay. We used inhibitor and siRNA to demonstrate that alpha7-nAChR mediated NNK-enhanced gastric cancer cell migration and upregulation of fibronectin were involved in NNK-enhanced migration of gastric cancer cells. Finally, we found that silenced fibronectin expression level inhibited the migratory ability in AGS cells. CONCLUSIONS: NNK enhanced gastric cancer metastasis through alpha7-nAChR and fibronectin-one of the hallmarks of epithelial mesenchymal transition.
