Downregulation of CD147 expression alters cytoskeleton architecture and inhibits gelatinase production and SAPK pathway in human hepatocellular carcinoma cells.
BACKGROUND
CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this study is to investigate the effects of small interfering RNA (siRNA) against CD147 (si-CD147) on hepatocellular carcinoma cells' (SMMC-7721) architecture and functions.


METHODS
Flow cytometry and western blot assays were employed to detect the transfection efficiency of si-CD147. Confocal microscopy was used to determine the effects of si-CD147 on SMMC-7721 cells' cytoskeleton. Invasion assay, gelatin zymography and cell adhesion assay were employed to investigate the effects of si-CD147 on SMMC-7721 cells' invasion, gelatinase production and cell adhesive abilities. Western blot assay was utilized to detect the effects of si-CD147 on focal adhesion kinase (FAK), vinculiln and mitogen-activated protein kinase (MAPK) expression in SMMC-7721 cells.


RESULTS
Downregulation of CD147 gene induced the alteration of SMMC-7721 cell cytoskeleton including actin, microtubule and vimentin filaments, and inhibited gelatinase production and expression, cells invasion, FAK and vinculin expression. si-CD147 also blocked SMMC-7721 cells adhesion to collagen IV and phosphorylation level of SAPK/JNKs. SAPK/JNKs inhibitor SP600125 inhibited gelatinase production and expression.


CONCLUSIONS
CD147 is required for normal tumor cell architecture and cell invasion. Downregulation of CD147 affects HCC cell structure and function. Moreover, the alteration of cell behavior may be related to SAPK/JNK Pathway. siRNA against CD147 may be a possible new approach for HCC gene therapy.
Key Laboratory for Space Biosciences & Biotechnology, Institute of Special Environmental Biophysics, Faculty of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, PR China. qianair@nwpu.edu.cn
Ai-Rong
AR
Qian
Wei
W
Zhang
Jian-Ping
JP
Cao
Peng-Fei
PF
Yang
Xiang
X
Gao
Zhe
Z
Wang
Hui-Yun
HY
Xu
Yuan-Yuan
YY
Weng
Peng
P
Shang
D000873:Anthracenes / Q000494:pharmacology; D051926:Basigin / Q000235:genetics / Q000502:physiology*; D006528:Carcinoma, Hepatocellular / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000648:ultrastructure*; D015536:Down-Regulation; D005434:Flow Cytometry; D051417:Focal Adhesion Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D018093:Gelatinases / Q000096:biosynthesis*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008113:Liver Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D034622:RNA Interference; D014407:Tumor Cells, Cultured; D016596:Vinculin / Q000037:antagonists & inhibitors / Q000378:metabolism
D000873:Anthracenes; C488955:VCL protein, human; D016596:Vinculin; D051926:Basigin; C432165:pyrazolanthrone; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048031:JNK Mitogen-Activated Protein Kinases; D018093:Gelatinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9