• The Korean Journal of Physiology and Pharmacology
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• v.6 no.4
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• pp.187-191
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• 2002

Tamoxifen, an antiestrogen, has previously been shown to induce apoptosis in HepG2 human hepatoblastoma cells through activation of the pathways independent of estrogen receptors, i.e., intracellular $Ca^{2+}$ increase and generation of reactive oxygen species (ROS). However, the mechanism of tamoxifen to link increased intracellular $Ca^{2+}$ to ROS generation is currently unknown. Thus, in this study we investigated the possible involvement of calmodulin, a $Ca^{2+}$ activated protein, and $Ca^{2+}$/calmodulin-dependent protein kinase II in the above tamoxifen-induced events. Treatment with calmodulin antagonists (calmidazolium and trifluoroperazine) or specific inhibitors of $Ca^{2+}$/calmodulin-dependent protein kinase II (KN-93 and KN-62) inhibited the tamoxifen-induced apoptosis in a dose-dependent manner. In addition, these agents blocked the tamoxifen-induced ROS generation in a concentration-dependent fashion, which was completely suppressed by intracellular $Ca^{2+}$ chelation. These results demonstrate for the first time that, despite of its well-known direct calmodulin-inhibitory activity, tamoxifen may generate ROS and induce apoptosis through indirect activation of calmodulin and $Ca^{2+}$/calmodulin-dependent protein kinase II in HepG2 cells.

• Archives of Pharmacal Research
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• v.28 no.1
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• pp.73-80
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• 2005

The effect of capsaicin on apoptotic cell death was investigated in HepG2 human hepatoma cells. Capsaicin induced apoptosis in time- and dose-dependent manners. Capsaicin induced a rapid and sustained increase in intracellular $Ca^{2+}$ concentration, and BAPTA, an intracellular $Ca^{2+}$ chelator, significantly inhibited capsaicin-induced apoptosis. The capsaicin-induced increase in the intracellular $Ca^{2+}$ and apoptosis were not significantly affected by the extracellular $Ca^{2+}$ chelation with EGTA, whereas blockers of intracellular $Ca^{2+}$ release (dantrolene) and phospholipase C inhibitors, U-73122 and manoalide, profoundly reduced the capsaicin effects. Interestingly, treatment with the vanilloid receptor antagonist, capsazepine, did not inhibit either the increased capsaicin-induced $Ca^{2+}$ or apoptosis. Collectively, these results suggest that the capsaicin-induced apoptosis in the HepG2 cells may result from the activation of a PLC-dependent intracellular $Ca^{2+}$ release pathway, and it is further suggested that capsaicin may be valuable for the therapeutic intervention of human hepatomas.

• Culinary science and hospitality research
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• v.15 no.1
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• pp.120-127
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• 2009

In this study, Pip(Pip) and shell powder(Cortex) extracts, and juice concentrates(Juice-1 and Juice-2) of Pomegranate were screened for their growth inhibition on HepG-2 cells and antioxidant activities on DPPH radical-scavenging activity. All samples with higher concentrations showed the growth inhibition against HepG-2 cells. The growth inhibitions against HepG-2 liver cancer cells at 2,500 ppm were in order of Juice-2(43%), Pip(42%), Cortex(38%) and Juice-1(29%). DPPH radical-scavenging activities were higher with the concentrations of the samples increased. The activities of antioxidant BHT, Pip, Cortex, Juice-1, and Juice-2 at 12.5 ppm were 29.9, 16.2, 60.8, 12.6, and 15.1% respectively and those at 25, 50, 100, and 200 ppm were in order of Cortex(81.9$\sim$85.3%), Pip(33.4$\sim$83.0%), BHT(31.3$\sim$47.8%), Juice-2(15.4$\sim$36.8%) and Juice-1(13.4$\sim$36.1%).

• Journal of Nutrition and Health
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• v.35 no.4
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• pp.439-445
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• 2002

This study was undertaken to investigate the inhibitory effect of prunus fume extracts on the growth of Hep G2 and HeLa cells. Prunus mums was extracted using the following solvents hexane, chloroform, ethylacetate, methanol, and hot water. The effect on the growth of each cancer cell line was examined by MTT (3-[4, 5-dimethylthiaeol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, cytotoxicity testing, and microscopic observation. The ethylacetate extracts of Prunus muse at the concentration of 250 $\mu\textrm{g}$/ml exhibited the greatest inhibitory effect on the growth of Hep G2 in the MW assay. In cytotoxicity testing, the treatment of the Hep G2 cells with ethylacetate extracts (1000 $\mu\textrm{g}$/ml for 72 hrs) destroyed 75% of the cells, and morphological changes were also observed. futhermore, the hexane extracts of Prunes muse at the concentration of 250 $\mu\textrm{g}$/ml exhibited the greatest inhibitory effect on the growth of HeLa cells in the MTT assay. The treatment of the HeLa cells with the hexane extracts (1000 $\mu\textrm{g}$/ml for 72 hrs) resulted in the destruction of 68% of the cells. Fibroblasts were not affected by either ethylacetate or hexane extracts of prunus muse.

• Journal of Ginseng Research
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• v.20 no.3
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• pp.241-247
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• 1996

The effects of ginseng total saponin, ginsenoside-Rb, and -Rb, on the reduction of chmlesterol level and the myNA expression rates of HMG CoA reductase and LDL receptor in Hep G2 were investigated and compared with that of lovastatin, a competitive HMG CoA reductase Inhibitor. The amounts of cholesterol in Hep G2 decreased in total saponin-and ginsenoside-treated groups as compared with that of control group, while there was no significant reduction in lovastatin-treated group. The mRNA expression rates of HMG CoA reductase increased in total saponin and gin- senoside groups except for ginsenoside-Rb, (10-3%) group and decreased in lovastatin group com- pared with that of control group. The mRNA expression rates of LDL receptor generally increased In all of the test groups except for total saponin (10-5%) group compared with that of control group. Because the ginseng components tested were more effective in the reduction of cholesterol level in Hep G2 than lovastatin and induced the gene expression of LDL receptor, we suggest the possibility that they could be used as a replacement agent for lovastatin which can not be prescribed especially to patients with hepatic diseases.

• Advances in Traditional Medicine
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• v.9 no.2
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• pp.106-114
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• 2009

Hepatocellular carcinoma is the world's most common primary malignant tumor of the liver. In-Jin-ho-Tang (IJHT) has been used as a traditional Chinese herbal medicine since ancient times, and today it is widely used as a medication for jaundice associated with inflammation of the liver. In-Jin-Ho-Tang is a drug preparation consisting of three herbs: Artemisiae Capillaris Herba (Artemisia capillaries $T_{HUNS}$, Injinho in Korean), Gardeniae Fructus (Gardenia jasminodes $E_{LLIS}$, Chija in Korean) and Rhei radix et rhizoma (Rheum palmatum L., Daehwang in Korean). This study investigated whether or not methanol extract of IJHT could induce HepG2 cancer cell death. Cytotoxic activity of IJHT on HepG2 cells was measured using an XTT assay, with an $IC_{50}$ value of $700{\mu}g/ml$ at 24 h Apoptosis induction by IJHT in HepG2 cells was verified by the cleavage of poly ADP-ribose polymerase, and a decrease in procaspase-3, -8, -9. Treatment of IJHT resulted in the release of cytochrome c into cytosol, loss of mitochondrial membrane potential (${\Delta}{\Psi}_m$), decrease in anti-apoptotic Bcl-2, and an increase in pro-apoptotic Bax expression. Thus, IJHT induced apoptosis in HepG2 cells via activation of caspase and mitochondria pathway. These results indicate that IJHT has potential as an anti-cancer agent.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1437-1449
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• 2007

In this study, the effect of extract of Corydalis yanhusuo (ECT) used in Oriental medicine therapy was investigated on the cell growth and apoptosis of HepG2 human hepatoma cells. It was found that ECT could inhibit the cell growth effectively in a dose-dependent manner, which was associated with morphological change and apoptotic cell death such as formation of apoptotic bodies, DNA fragmentation and increased populations of apoptotic-sub G1 phase. And we observed the effects of ECT on loss of mitochondrial membrane potential (MMP), using the JC-1 probe by DNA flow cytometric analysis. Apoptosis of HepG2 cells by ECT was associated with a down-regulation of anti apoptotic Bcl-2 expression, inhibitor of apoptosis proteins (IAPs) expression and proteolytic activation of caspase-3 and caspase-9. However, ECT did not affect the pro-apoptotic Bax expression and activity of caspase-8. ECT treatment also concomitant degradation and /or inhibition of poly (ADP-ribose) polymerase (PARP), phospholipase C-1 ($PLC{\gamma}1$). Furthermore, ECT treatment caused a dose-dependent inhibition of iNOS and cyclooxygenase-2 (Cox-2). Additionally ECT have been implicated in the regulation of telomerase expression. ECT treatment induced the down-regulation of telomerase reverse transcriptase mRNA (hTERT) expression of HepG2 cells. Taken together, these findings suggest that ECT may be a potential chemotherapeutic agent for the control of HepG2 human hepatoma cells.

• Archives of Pharmacal Research
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• v.27 no.3
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• pp.305-313
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• 2004

The effect of diazoxide, a $K^{+}$channel opener, on apoptotic cell death was investigated in HepG2 human hepatoblastoma cells. Diazoxide induced apoptosis in a dose-dependent manner and this was evaluated by flow cytometric assays of annexin-V binding and hypodiploid nuclei stained with propidium iodide. Diazoxide did not alter intracellular $K^{+}$concentration, and various inhibitors of $K^{+}$channels had no influence on the diazoxide-induced apoptosis; this implies that $K^{+}$channels activated by diazoxide may be absent in the HepG2 cells. However, diazoxide induced a rapid and sustained increase in intracellular $Ca^{2+}$ concentration, and this was completely inhibited by the extracellular $Ca^{2+}$ chelation with EGTA, but not by blockers of intracellular $Ca^{2+}$ release (dantrolene and TMB-8). This result indicated that the diazoxide-induced increase of intracellular $Ca^{2+}$ might be due to the activation of a Ca2+ influx pathway. Diazoxide-induced $Ca^{2+}$ influx was not significantly inhibited by either voltage-operative $Ca^{2+}$ channel blockers (nifedipinen or verapamil), or by inhibitors of $Na^{+}$, $Ca^{2+}$-exchanger (bepridil and benzamil), but it was inhibited by flufenamic acid (FA), a $Ca^{2+}$-permeable nonselective cation channel blocker. A quantitative analysis of apoptosis by flow cytometry revealed that a treatment with either FA or BAPTA, an intracellular $Ca^{2+}$ chelator, significantly inhibited the diazoxide-induced apoptosis. Taken together, these results suggest that the observed diazoxide-induced apoptosis in the HepG2 cells may result from a $Ca^{2+}$ influx through the activation of $Ca^{2+}$-permeable non-selective cation channels. These results are very significant, and they lead us to further suggest that diazoxide may be valuable for the therapeutic intervention of human hepatomas.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.493-499
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• 2007

Celastrus orbiculatus (CO) has been used as a traditional herb medicine to treat fever, chill, joint pain, edema, rheumatoid arthritis and bacterial infection in China and Korea. In this study, we investigated anticarcinogenic effects of Celastrus orbiculatus (CO). CO was extracted with methanol (COM), and then further fractionated into four different types: methanol (COMM), hexane (COMH), butanol (COMB) and aqueous (COMA) partition layers. We determined the cytotoxicity of these four partitions in four kind of cancer cell lines, such as HepG2, MCF-7, HT29 and B16F10 Cells by MTT assay. Among various partition layers of CO, the COMM showed the strongest cytotoxic effects on cancer cell lines we used. We also observed quinone reductase (QR) induced effects in all partition layers of CO on HepG2 cells. The QR induced effects of COMM on HepG2 cells at 80 ${\mu}$ g/mL concentration indicated 3.28 to a control value of 1.0. The COMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers. Although further studies are needed, the present work suggests that CO may be a chemopreventive agent for the treatment of human cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2305-2309
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• 2012

Crocin, the main pigment of Crocus sativus L., has been shown to have antiproliferative effects on cancer cells, but the involved mechanisms are only poor understood. This study focused on probable effect of crocin on the immortality of hepatic cancer cells. Cytotoxicity of crocin ($IC_{50}$ 3 mg/ml) in hepatocarcinoma HepG2 cells was determined after 48 h by neutral red uptake assay and MTT test. Immortality was investigated through quantification of relative telomerase activity with a quantitative real-time PCR-based telomerase repeat amplification protocol (qTRAP). Telomerase activity in 0.5 ${\mu}g$ protein extract of HepG2 cells treated with 3 mg/ml crocin was reduced to about 51% as compared to untreated control cells. Two mechanisms of inhibition, i.e. interaction of crocin with telomeric quadruplex sequences and down regulation of hTERT expression, were examined using FRET analysis to measure melting temperature of a synthetic telomeric oligonucleotide in the presence of crocin and quantitative real-time RT-PCR, respectively. No significant changes were observed in the $T_m$ telomeric oligonucleotides, while the relative expression level of the catalytic subunit of telomerase (hTERT) gene showed a 60% decrease as compared to untreated control cells. In conclusion, telomerase activity of HepG2 cells decreases after treatment with crocin, which is probably caused by down-regulation of the expression of the catalytic subunit of the enzyme.