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Effect of baicalein on apoptosis of human hepatoma cell line SMMC-7721

Journal Of Modern Oncology[ISSN:1672-4992/CN:61-1415/R]

Issue:
2012 06
Page:
1098-1103
Research Field:
Publishing date:

Info

Title:
Effect of baicalein on apoptosis of human hepatoma cell line SMMC-7721
Author(s):
XIANG Miao; XU Ximing; DENG Junjian; YANG Jiao; CHEN Biao; ZHANG Yiqiao
Cancer Center, People's Hospital of Wuhan University, Hubei Wuhan 430060, China.
Keywords:
human hepatoma cell line SMMC-7721;  12-lipoxygenase;  apoptosis
PACS:
R730.5；R735.7
DOI:
10.3969/j.issn.1672-4992.2012.06.02
Abstract:
Objective：To examine the expression of 12-lipoxygenase (12-LOX) in human hepatoma cell line SMMC-7721, investigate the effect of its selective inhibitor baicalein on cell growth and apoptosis. WT5Methods: Immunocytochemical staining and RT-PCR were used to detect the expressions of 12-lox protein and mRNA in SMMC-7721cells. Cell growth and apoptosis were detemined by MTT assay,flow cytometry and TUNEL assay . Western blot analysis was used to detect the expressions of Caspase-3, Bcl-2, Bax, phospho-ERK1/2 , ERK1/2 and β-actin protein. Results: The expression of 12-LOX protein was detected in SMMC-7721 cells cytoplasm. The mRNA expression of 12-LOX was detected with RT-PCR which showed that baicalein inhibited the expression of mRNA in a concentration- and time-dependent manner. The SMMC-7721 cells were treated with various concentrations of baicalein or were exposed to baicalein at 20 μmol/L for different time periods,MTT assayed that the cell growth decreased in a dose-time dependent manner. TUNEL assay and flow cytometry were used to confirm that induction of cell apoptosis by 12-LOX inhibition. After treatment with baicalein, a marked downregulation of Bcl-2 protein and a slight upregulation of Bax protein were observed. The levels of active Caspase-3 were increased gradually in a concentration-dependent manner after exposure to baicalein. The effects of baicalein on the above apoptosis-related proteins were reversed by the exogenous 12 (S)-HETE. 12 (S)-HETE may activate phosphorylation of ERK1/2. Conclusion: The expression of 12-LOX protein was detected in SMMC-7721 cells cytoplasm. Inhibition of 12-LOX caused inhibition of cell growth and induction of apoptosis in HCC cells.

References:

［1］Parkin DM, Bray F, Ferlay J， et al. Global cancer statistics, 2002［J］. CA Cancer J Clin, 2005,55(2):74-108.
［2］McGlynn KA, London WT. Epidemiology and natural history of hepatocellular carcinoma［J］. Best Pract Res Clin Gastroenterol, 2005,19(1):3-23.
［3］El-Serag HB, Rudolph KL. Hepatocellular carcinoma: epidemiology and molecular carcinogenesis［J］. Gastroenterology, 2007,132(7):2557-2576.
［4］Ding XZ, Hennig R, Adrian TE. Lipoxygenase and cyclooxygenase metabolism: new insights in treatment and chemoprevention of pancreatic cancer［J］. Mol Cancer, 2003,7（2）:10-11.
［5］Steele VE, Holmes CA, Hawk ET, et al. Lipoxygenase inhibitors as potential cancer chemopreventives［J］. Cancer Epidemiol Biomarkers Prev,1999,8(5):467-483.
［6］Matsuyama M, Yoshimura R, Mitsuhashi M， et al. Expression of lipoxygenase in human prostate cancer and growth reduction by its inhibitors［J］. Int J Oncol, 2004,24(4):821-827.
［7］Zhi H, Zhang J, Hu G, et al. The deregulation of arachidonic acid metabolism-related genes in human esophageal squamous cell carcinoma［J］. Int J Cancer,2003,106(3):327-333.
［8］Yoshimura R, Inoue K, Kawahito Y, et al. Expression of 12-lipoxygenase in human renal cell carcinoma and growth prevention by its inhibitor［J］. Int J Mol Med, 2004,13(1):41-46.
［9］Yoshimura R, Matsuyama M, Tsuchida K，et al. Expression of lipoxygenase in human bladder carcinoma and growth inhibition by its inhibitors［J］. J Urol,2003,170(5):1994-1999.
［10］Pidgeon GP, Tang K, Cai YL， et al. Overexpression of platelet-type 12-lipoxygenase promotes tumor cell survival by enhancing alpha(v)beta(3) and alpha(v)beta(5) integrin expression［J］. Cancer Res,2003,63(14):4258-4267.
［11］Nie D, Nemeth J, Qiao Y， et al . Increased metastatic potential in human prostate carcinoma cells by overexpression of arachidonate 12-lipoxygenase［J］. Clin Exp Metastasis,2003,20(7):657-663.
［12］Pidgeon GP, Kandouz M, Meram A， et al. Mechanisms controlling cell cycle arrest and induction of apoptosis after 12-lipoxygenase inhibition in prostate cancer cells［J］. Cancer Res, 2002,62(9):2721-2727.
［13］Wong BC, Wang WP, Cho CH， et al. 12-Lipoxygenase inhibition induced apoptosis in human gastric cancer cells［J］. Carcinogenesis,2001,22(9):1349-1354.
［14］Leung HW, Yang WH, Lai MY， et al. Inhibition of 12-lipoxygenase during baicalein-induced human lung nonsmall carcinoma H460 cell apoptosis［J］. Food Chem Toxicol,2007,45(3):403-411.
［15］Burlacu A. Regulation of apoptosis by Bcl-2 family proteins［J］. J Cell Mol Med,2003,7(3):249-257.
［16］Porter AG, Jnicke RU. Emerging roles of caspase-3 in apoptosis［J］. Cell Death Differ, 1999,6(2):99-104.
［17］Pearson G, Robinson F, Beers Gibson T， et al. Mitogen-activated protein (MAP) kinase pathways: regulation and physiological functions［J］. Endocr Rev,2001,22(2):153-183.
［18］Balmanno K,Cook SJ.Tumour cell survival signalling by the ERK1/2 pathway［J］.Cell Death Differ,2009,16(3):368-377.
［19］Ito Y, Sasaki Y, Horimoto M， et al. Activation of mitogen-activated protein kinases/extracellular signal-regulated kinases in human hepatocellular carcinoma［J］. Hepatology,1998,27(4):951-958.
［20］Mitsushima M, Suwa A, Amachi T， et al. Extracellular signal-regulated kinase activated by epidermal growth factor and cell adhesion interacts with and phosphorylates vinexin［J］. J Biol Chem,2004,279(33):34570-34577.
［21］Ding XZ, Tong WG, Adrian TE. 12-lipoxygenase metabolite 12(S)-HETE stimulates human pancreatic cancer cell proliferation via protein tyrosine phosphorylation and ERK activation［J］. Int J Cancer,2001,94(5):630-636.（编校：张志明）

Memo

Memo:
国家自然科学基金资助项目（编号：81000998）；湖北省自然科学基金资助项目（编号：20090141120003）
Last Update: 2012-06-11