• Radiation Oncology Journal
• /
• v.22 no.3
• /
• pp.217-224
• /
• 2004

Purpose: It is well known that the radiosensitivity of tumor cells can be significantly reduced under hypoxic conditions. Hypoxia-inducible factor-1 $\alpha$ (HIF-1 $\alpha$) plays a pivotal role in the essential adaptive responses to hypoxia. Therefore this study investigated the relationship between HIF-1 $\alpha$ expression and radiosensitivity. M Mouse hepatoma cell line hepafcic7 and HIF-1 $\beta$-deficient mutant cell line hepa1C4 were used to analyze the role of HIF-1 a. on radiosensitivity. These cells were exposed for 6 h to desferrioxamine (DFX) before radiation. HIF-1$\alpha$. expression was examined by Western blot. Apoptosis was assessed by DNA fragmentation, propidium iodide staining, and apoptotic cell death detection ELISA kit. Radiation sensitivity was determined using MTT assay. The radiobioiogical parameters, surviving fractions at 2 Gy and 8 Gy, and mean inactivation dose (MID) from the linear-quadratic model were used to assess radiation sensitivity in the statistical analyses. Results: The expression of HIF-1 $\alpha$. was Increased, whereas apoptosis was decreased, by radiation In the presence of DFX In hepal cl c7, but not In hepal C4. The radlosensitivity of hepal C4 cells was not significantly affected by DFX treatment. The radiosensitivlty of hepal cl c7 cells was significantly decreased in the presence of DFX Conclusion: The expression of HIF-1 w by hypoxia-mimic agent DFX reduced apoptosls and radiosensitlvity in mouse hepatoma cell line hepafclc7. These results suggested that HIF-1 u could be Induced by irradiation in hypoxic ceils of tumor masses, and that this mlght Increase radioresistance in hypoxic cells.

• The Korean Journal of Nuclear Medicine
• /
• v.38 no.1
• /
• pp.62-73
• /
• 2004

Purpose: The herpes simplex virus type 1 thymidine kinase gene(HSV1-tk) is an attractive candidate as a reporter gene in noninvasive reporter gene monitoring system. The HSV1-tk gene was chosen as a reporter gene, because it has been extensively studied, and there are appropriate reporter probes, substrates of HSV1-tk gene product, to apply for HSV1-tk gene imaging. We used radiolabeled 5-iodovinyl-2'-deoxyuridine (IVDU) and 5-iodovinyl-2'-fluoro-2'-deoxyuridine (IVFRU) as reporter probes for HSV1-tk gene monitoring system. Materials and Methods: We prepared HSV1-tk gene transduced Morris hepatoma cell line using retroviral vector, MOLTEN containing HSV1-tk gene. And we confirmed the HSV1-tk gene expression by Northern blotting and Western blotting. We compared in vitro uptakes of radioiodinated IVDU and IVFRU to monitor HSV1-tk gene expression in Morris hepatoma cell line (MCA) and HSV1-tk gene tranduced MCA (MCA-tk) cells until 480 minutes. We also peformed correlation analysis between percentage of HSV1-tk gene tranduced MCA cell % (MCA-tk%) and uptakes of radiolabeled IVDU or IVFRU. Results: MCA-tk cell expressed HSV1-tk mRNA and HSV1-TK protein. Two compounds showed minimal uptake in MCA, but increased uptake was observed in MCA-tk. IVDU showed 4-fold higher accumulation than IVFRU at 480 min in MCA-tk (p<0.01). Both IVDU and IVFRU uptake were linearly correlated ($R^2>0.96$) with increasing MCA-tk%. Conclusion: The radiolabeld IVDU and IVFRU showed higher specific accumulation in retrovirally HSV1-tk gene transfected Morris hepatoma cell line. Both IVDU and IVFRU could be used as good substrates for evaluation of HSV1-tk gene expression.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.1
• /
• pp.5-9
• /
• 2013

Rhomboids were identified as the first intramembrane serine proteases about 10 years ago. Since then, the study of the rhomboid protease family has blossomed. Rhomboid domain containing 1 (RHBDD1), highly-expressed in human testis, contains a rhomboid domain with unknown function. In the present study, we tested the hypothesis that RHBDD1 was associated with proliferation and apoptosis in hepatocellular carcinoma using recombinant lentivirus-mediated silencing of RHBDD1 in HepG2 cells. Our results showed that down-regulation of RHBDD1 mRNA levels markedly suppressed proliferation and colony formation capacity of HepG2 human hepatoma cancer cells in vitro, and induced cell cycle arrest. We also found that RHBDD1 silencing could obviously trigger HepG2 cell apoptosis. In summary, it was demonstrated that RHBDD1 might be a positive regulator for proliferative and apoptotic characteristics of hepatocellular carcinoma.

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

• Food Science and Biotechnology
• /
• v.14 no.2
• /
• pp.297-300
• /
• 2005

Effects of allyl sulfides on kinetic behavior of cytochrome P450 1 (CYP1)-catalyzed ethoxyresorufin O-deethylase (EROD) activity were studied using microsomes from benzo[a]pyrene-treated human hepatoma cells. Apparent $K_m$ and $V_{max}$ values were calculated as $2.8\;{\mu}M$ and $3.0\;{\mu}mol$ resorufin/min/mg protein based on Lineweaver-Burk plot of microsomal EROD activity, respectively. Diallyl disulfide (DADS) and diallyl trisulfide (DATS) affected $K_m$ and $V_{max}$ values of EROD activity and acted as mixed-type inhibitors for CYP1 isozymes. Apparent Ki values of DADS and DATS were calculated as 1.07 and 0.88 mM, respectively, by re-plotting slopes of Lineweaver-Burk plot and inhibitor concentrations.

• BMB Reports
• /
• v.44 no.12
• /
• pp.782-786
• /
• 2011

Aberrant GAPDH expression following S-nitrosoglutathione (GSNO) treatment was compared in HepG2 cells, which express functional p53, and Hep3B cells, which lack functional p53. The results of Western blotting and fluorescent immunocytochemistry revealed that nuclear translocation and accumulation of GAPDH occur in both HepG2 and Hep3B cells. This finding suggests that p53 may not be necessary for the GSNO-induced translocation of GAPDH to the nucleus during apoptotic cell death in hepatoma cells.

• YAKHAK HOEJI
• /
• v.38 no.1
• /
• pp.6-11
• /
• 1994

The MeOH extract of the fruits of Melia toosendan was selected for futher study by its cytotoxicity and effect on the human breast cancer cell line, MCF-7. The active principle obtained by activity guided fractionation followed by purification gave rise to a needle crystal. The structure was deduced by employing NMR and was determined to be identical with 28-deacetyl sendanin by comparison with published data. This compound induced morphological change of MCF-7 to be rounded with tubule at concentrations between $50\;{\mu}g/ml$ and $0.025\;{\mu}g/ml$. This compound, however, showed strong cytotoxic effect on Hepalclc7 and HepG2, and their $GI_{50}$ on the hepatoma cell lines were $0.238\;{\mu}g/ml$ and $0.805\;{\mu}g/ml$, respectively. Its effect on lymphocyte of mouse was stronger than hepatoma cell lines, and their $ED_{50}$ of polyclonal antibody response was $0.011\;{\mu}g/ml$, and $ED_{50}$ of cell viability was $0.039\;{\mu}g/ml$.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.3
• /
• pp.1025-1029
• /
• 2012

Objective: To determine the killing effects on extracorporeal HepG2 cells under different temperatures, pressures of permeability and lengths of treatment time. Method: According to different temperatures, pressures of permeability and lengths of treating time, extracorporeal HepG2 cells of human hepatoma cell-line were grouped to 80 groups. Cell index (CI) as the measurement of killing effect were calculated by monotetrazolium (MTT) methods, i.e., CI =1- (the OD value in treated group - the OD value in blank control group) / (mean of untreated control group - mean of blank control group). According to the factorial design, data were fed into SPSS 10.0 and analyzed by three-way ANOVA (analysis of variance). Result: Temperature, pressure of permeability and length of treating time all had effects on the CI (cell index) level. Length of treating time was the most influential factor of the three. Additionally, any two of them all had statistically significant interactive effects on the CI level. When treated for 5-30 min, destilled water at $46^{\circ}C$ stably generated the highest CI. Conclusion: The "$46^{\circ}C$-destilled water-60 min" was considered as the optimal combination of conditions which lead to highest CI. We suggest exerting celiac lavage for 15 min with stilled water at $40^{\circ}C-43^{\circ}C$ in surgical practice as a hyperthermia treatment to achieve ideal killing effects on free cancer cells, which is feasible, practical, and clinically effective.

• Korean Journal of Plant Resources
• /
• v.25 no.5
• /
• pp.647-651
• /
• 2012

The objective of this study was to investigate the anticancer effects of the extracts of oriental melon seeds. Various solvent extracts of oriental melon seeds were prepared and their anticancer effects were examined using in vitro MTT and CV assays. The anticancer effects of various extracts of oriental melon seeds were also examined in five human cancer cell lines including A549, AGS, HT-29, MCF-7 and HepG2. The ethanol extract of heated oriental melon seeds showed the potent cytotoxic effects especially against mouse hepatoma cell line(Hepa1c1c7), human hepatoma cell line(HepG2) and human breast cancer cell line(MCF-7). These data suggest that oriental melon seeds can be a promising anticancer agent against human liver and breast cancer.

• Preventive Nutrition and Food Science
• /
• v.19 no.4
• /
• pp.268-273
• /
• 2014

The induction of detoxification enzymes by benzyl isothiocyanate (BITC) and its synthetic N-acetyl-L-cysteine (NAC) conjugate (NAC-BITC) was examined in Hepa1c1c7 murine hepatoma cells. BITC and NAC-BITC inhibited Hepa1c1c7 cell growth in a dose-dependent manner. Cell growth was 4.5~57.2% lower in Hepa1c1c7 cells treated with $0.1{\sim}1.0{\mu}M$ BITC than in control-treated Hepa1c1c7 cells. The NAC-BITC treatment had a similar inhibitory pattern on Hepa1c1c7 cell growth; $0.5{\mu}M$ and $10{\mu}M$ NAC-BITC decreased cell growth by 13.6% and 47.4%, respectively. Treatment of Hepa1c1c7 cells with $0.1{\sim}2.0{\mu}M$ BITC also elicited a dose-response effect on the induction of quinone reductase quinone reductase (QR) activity and QR mRNA expression. Treatment with $1{\mu}M$ and $2{\mu}M$ BITC caused 1.8- and 2.8-fold inductions of QR mRNA, respectively. By comparison, treatment with $1{\mu}M$ and $2{\mu}M$ NAC-BITC caused 1.6-and 1.9-fold inductions of QR mRNA, respectively. Cytochrome P450 (CYP) 1A1 and CYP2E1 induction were lower in $0.1{\sim}2{\mu}M$ BITC-treated cells than in control-treated cells. CYP2E1 activity was 1.2-fold greater in $0.1{\mu}M$ NAC-BITC-treated cells than in control-treated cells. However, the CYP2E1 activity of cells treated with higher concentrations (i.e., $1{\sim}2{\mu}M$) of NAC-BITC was similar to the activity of control-treated cells. Considering the potential of isothiocyanatesto prevent cancer, these results provide support for the use of BITC and NAC-BITC conjugates as chemopreventive agents.