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ABSTRACT: Recent studies revealed the potential of Na(+)/K(+)-ATPase as a target for anticancer therapy and showed additional modes of action of cardiotonic steroids (CSs), a diverse family of naturally derived compounds, as inhibitors of Na(+)/K(+)-ATPase. The results from epidemiological studies showed significantly lower mortality rates in cancer patients receiving CSs, which sparked interest in the anticancer properties of these drugs. The present study was designed to investigate the anticancer effect of CSs (ouabain or cinobufagin) and to elucidate the molecular mechanisms of CS activity in hepatoma cell lines (HepG2 and SMMC-7721). Ouabain and cinobufagin significantly inhibited cell proliferation by attenuating the phosphorylation of extracellular regulated kinase (ERK) and down-regulating the expression of C-myc. These CSs also induced cell apoptosis by increasing the concentration of intracellular free calcium ([Ca(2+)](i)) and induced S phase cell cycle arrest by down-regulating the expression of Cyclin A, cyclin dependent kinase 2 (CDK2) and proliferating cell nuclear antigen (PCNA) as well as up-regulating the expression of cyclin dependent kinase inhibitor 1A (p21(CIP1)). Overexpression of ERK reversed the antiproliferation effect of ouabain or cinobufagin in HepG2 and SMMC-7721 cells. Currently, the first generation of CS-based anticancer drugs (UNBS1450 and Anvirzel) are in Phase I clinical trials. These data clearly support their potential use as cancer therapies.
The Journal of steroid biochemistry and molecular biology 01/2011; 125(3-5):181-91. · 2.66 Impact Factor
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ABSTRACT: To investigate the in vitro anti-cancer effects of ouabain combined Na(+)/K(+)-ATPase alpha1 siRNA upon HepG2 cells and its molecular mechanism.
The Na(+)/K(+)-ATPase alpha1 subunit expressions of human hepatoma tissue, normal liver tissue and human hepatoma cell lines (HepG2, SMC7721 and Bel7402) were determined. The cells received different treatments (0.03 micromol/L siRNA, 0.1 micromol/L ouabain and combination). The proliferation of HepG2 was observed by CCK-8 assay. The activity of Na(+)/K(+)-ATPase was measured. The HepG2 cell cycle distribution was detected by flow cytometry. The mRNA and protein levels of Na(+)/K(+)-ATPase alpha1 subunit, MAPK1, Cyclin A, CDK2, PCNA and P21WAF1 were detected by quantitative RT-PCR and Western blot.
The gray value Na(+)/K(+)-ATPase alpha1 subunit in hepatoma tissue was 174.74 +/- 16.77 and 65.31 +/- 7.88 respectively in normal liver tissue. The Na(+)/K(+)-ATPase alpha1 subunit expression of hepatoma tissue was significantly higher than normal liver tissue(P < 0.05).The Na(+)/K(+)-ATPase alpha1 subunit expression level of HepG2 was higher than that in SMMC-7721 and Bel-7402 cells. The CCK-8 experiments demonstrated that siRNA, ouabain and combination could inhibit the HepG2 proliferation, and the combination group was different from the ouabain or siRNA group (P < 0.05). The 24, 48 and 72 h inhibitory rates of 0.03 micromol/L siRNA, 0.1 micromol/L ouabain and combination group were (17.4%, 20.3%, 24.3%), (37.5%, 44.3%, 51.2%) and (52.3%, 70.2%, 88.2%) respectively. The activity of Na(+)/K(+)-ATPase decreased in siRNA, ouabain and combination group. The S phase proportion of ouabain and combination group increased from 24.2% to 66.5% and 75.2% respectively. The 0.1 micromol/L ouabain and combination group could down-regulate the expression of Na(+)/K(+)-ATPsae alpha1, MAPK1, Cyclin A, CDK2, PCNA and up-regulate the expression of P21WAF1 in HepG2 cell.
The Na(+)/K(+)-ATPase alpha1 siRNA combined ouabain inhibits the proliferation of HepG2 cells by decreasing the expression of MAPK1 and induces the cell cycle S arrest by decreasing the production of Cyclin A/CDK2/PCNA complex and increasing the expression of P21(WAF1).
Zhonghua yi xue za zhi 03/2010; 90(12):813-7.
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ABSTRACT: Recent research has shown that the Na(+)/K(+)-ATPase alpha1 subunit is a novel anti-cancer target, which plays pivotal roles in malignant cell ion transport, metabolism, migration and signal transduction. The purpose of the present study was to investigate the anti-cancer effects of ouabain and Na(+)/K(+)-ATPase alpha1 small interfering ribonucleic acid (siRNA) on HepG2 cell proliferation, apoptosis and cell cycle, and to explore the molecular mechanisms. The expression of Na(+)/K(+)-ATPase alpha1 subunit in human hepatocellular carcinoma (HCC), normal liver tissues and human HCC line (HepG2, SMMC-7721 and Bel-7402) has been investigated. Using the ouabain and Na(+)/K(+)-ATPase alpha1 subunit siRNA, which target the Na(+)/K(+)-ATPase, we have evaluated the effects of inhibiting Na(+)/K(+)-ATPase alpha1 in human HepG2 cells with respect to cell proliferation, morphology, cell cycle, impact on intracellular Ca2++, reactive oxygen species (ROS) concentration, and correlated gene expression level on messenger ribonucleic acid (mRNA) and protein. Our data showed that the expression Na(+)/K(+)-ATPase alpha1 subunit in HCC tissues is higher than that in normal liver tissues. Ouabain and Na(+)/K(+)-ATPase alpha1 siRNA could inhibit HepG2 cell proliferation. Ouabain could induce HepG2 cell apoptosis and generate S phase arrest, and siRNA could enhance the anti-cancer effect of ouabain that induced HepG2 cells apoptosis via an intracellular Ca(2+) and ROS increase-mediated, and generated cell cycle S phase arresting by decreasing the CyclinA1/cyclin-dependent kinase 2 (CDK2)/proliferating cell nuclear antigen (PCNA) complex product and increasing the expression of cyclin-dependent kinase inhibitor 1A (P21(CIP1)). We believe that targeting of the Na(+)/K(+)-ATPase alpha1 subunit in human HCC cells could provide new sight into the treatment of HCC.
Biological & Pharmaceutical Bulletin 01/2010; 33(5):743-51. · 1.66 Impact Factor
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ABSTRACT: To summarize the experience of treatment in 32 critical severe acute respiratory syndrome (SARS) patients.
The age of 32 patients ranged from 19 to 72 years, the average was 43.06 years. Among them, 13 patients were having serious primary diseases, i.e. cardio-cerebral-vascular disease in 9 patients, diabetes in 2 patients, renal dysfunction in 1 patient, and chronic obstructive pulmonary disease (COPD) in 1 patient. The treatment included antiviral agents, glucocorticoid, mechanical ventilation, antibiotics and immunologic enhancement, etc. Cure rate, mortality and complications were analyzed.
Among 32 patients, 24 were cured, 2 died of respiratory failure, 6 died of their primary diseases, and the overall mortality was 25.00 percent. Superimposed infection occurred in 12 patients, and among 17 patients who required noninvasive ventilation, 3 patients were complicated by lung injury (mediastinal emphysema, pneumothorax). In addition, hyperglycemia was found in 4 patients, upper intestinal hemorrhage occurred in another 4 patients and cardiac failure occurred in 6 patients.
The treatment of the pre-existing diseases should be emphasized in the treatment of critical SARS. Glucocorticoid should not be used for a long-term. Vigilance should be paid to avoid lung injury during mechanical ventilation.
Zhongguo wei zhong bing ji jiu yi xue = Chinese critical care medicine = Zhongguo weizhongbing jijiuyixue 09/2003; 15(8):492-4.
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Zhongguo wei zhong bing ji jiu yi xue = Chinese critical care medicine = Zhongguo weizhongbing jijiuyixue 08/2003; 15(7):400.
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Zhongguo wei zhong bing ji jiu yi xue = Chinese critical care medicine = Zhongguo weizhongbing jijiuyixue 08/2003; 15(7):397.
