• Proceedings of the Korean Society of Food Science and Nutrition Conference
• /
• 2003.11a
• /
• pp.91-91
• /
• 2003

• Proceedings of the Korean Society of Life Science Conference
• /
• 2001.09a
• /
• pp.40-40
• /
• 2001

• Proceedings of the Korea Environmental Mutagen Society Conference
• /
• 2004.05a
• /
• pp.65-65
• /
• 2004

• Proceedings of the Korean Society of Life Science Conference
• /
• 2001.02a
• /
• pp.44-44
• /
• 2001

• Proceedings of the Korean Nutrition Society Conference
• /
• 2001.05a
• /
• pp.302.2-302
• /
• 2001

• BMB Reports
• /
• v.48 no.11
• /
• pp.609-617
• /
• 2015

NAD(P)H:quinone oxidoreductase (NQO1), an obligatory two-electron reductase, is a ubiquitous cytosolic enzyme that catalyzes the reduction of quinone substrates. The NQO1- mediated two-electron reduction of quinones can be either chemoprotection/detoxification or a chemotherapeutic response, depending on the target quinones. When toxic quinones are reduced by NQO1, they are conjugated with glutathione or glucuronic acid and excreted from the cells. Based on this protective effect of NQO1, the use of dietary compounds to induce the expression of NQO1 has emerged as a promising strategy for cancer prevention. On the other hand, NQO1-mediated two-electron reduction converts certain quinone compounds (such as mitomycin C, E09, RH1 and β-lapachone) to cytotoxic agents, leading to cell death. It has been known that NQO1 is expressed at high levels in numerous human cancers, including breast, colon, cervix, lung, and pancreas, as compared with normal tissues. This implies that tumors can be preferentially damaged relative to normal tissue by cytotoxic quinone drugs. Importantly, NQO1 has been shown to stabilize many proteins, including p53 and p33ING1b, by inhibiting their proteasomal degradation. This review will summarize the biological roles of NQO1 in cancer, with emphasis on recent findings and the potential of NQO1 as a therapeutic target for the cancer therapy.

• Journal of Nutrition and Health
• /
• v.39 no.5
• /
• pp.444-450
• /
• 2006

In this study, we investigated antimicrobial and cytotoxicity effects to each· fraction extracted from Hizikiafusifonnis (HF), which were extracted methanol (HFM) and then the extract was fractionated into four different types: hexane (HFMH) , methanol (HFMM) , bulanol (HFMB) and aquous (HFMA) partition layers. We determined the cytotoxic effect of these layers on human cancer cells by MIT assay. Among various partition layers of HF, the HFMB and HFMM were showed the strong cytotoxic effects on cancer cell lines we used. The quinone reductase (QR) induced activity of the HFMB on HcpG2 cells at $150\;{\mu}g/mL$ concentration was 2.63 times more effective compared to the control value of 1.0. Although further studies are needed, the present work suggests that HF maybe a chemopreventive agent for the treatment of human cancer cells.

• Korean Journal of Pharmacognosy
• /
• v.34 no.4 s.135
• /
• pp.297-302
• /
• 2003

Cnidii Rhizoma water extract (CRW) was tested for liver cancer chemopreventive potential by measuring the inhibition of phase I enzyme and benzo[a]pyrene-DNA adduct formation and induction of phase II detoxification enzymes. There was 17.0% inhibition in the activity of cytochrome P450 1A1 enzyme with the treatment of 150 mg/ml CRW. At concentration of 30 mg/ml CRW, the binding of $[^3H]B[a]P$ metablites to DNA of NCTC-clone 1469 cell was inhibited by 33.3%. CRW was potent inducer of quinone reductase (QR) and glutathione S-transferase (GST) activities in cultured murine hepatoma Hepalc1c7 cells. However, hepatic glutathione (GSH) level was not influenced by CRW. These findings suggest that CRW has chemopreventive potential of liver cancer by inhibiting cytochrome P450 1A1 activity and benzo[a]pyrene-DNA adduct formation and inducing QR and GST activities.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.7
• /
• pp.4235-4238
• /
• 2013

Glucoraphanin is the main glucosinolate found in broccoli and other cruciferous vegetables (Brassicaceae). The objective of the study was to evaluate whether glucoraphanin and its breakdown product sulforaphane, are potent modulators of various phase I and phase II enzymes involved in carcinogen-metabolising enzyme systems in vitro. The glucosinolate glucoraphanin was isolated from cruciferous vegetables and exposed to human hepatoma cell line HepG2 at various concentrations (0-25 ${\mu}M$) for 24 hours. Glucoraphanin at higher concentration (25 ${\mu}M$) decreased dealkylation of methoxyresorufin, a marker for cytochrome P4501 activity; supplementation of the incubation medium with myrosinase (0.018 U), the enzyme that converts glucosinolate to its corresponding isothiocyanate, showed minimal induction in this enzyme activity at concentration 10 ${\mu}M$. Quinone reductase and glutathione S-transferase activities were unaffected by this glucosinolate; however, supplementation of the incubation medium with myrosinase elevated quinone reductase activity. It may be inferred that the breakdown product of glucoraphanin, in this case sulforaphane, is superior than its precursor in modulating carcinogen-metabolising enzyme systems in vitro and this is likely to impact on the chemopreventive activity linked to cruciferous vegetable consumption.

• Archives of Pharmacal Research
• /
• v.29 no.3
• /
• pp.209-212
• /
• 2006

We investigated the effect of protein extract of Asterina pectinifera on the activity of 4 enzymes that may playa role in adenocarcinoma of the colon: quinone reductase (QR), glutathione Stransferase (GST), ornithine decarboxylase (ODC), and cyclooxygenase (COX)-2. QR and GST activity increased in HT-29 human colon adenocarcinoma cells increased that had been exposed to 4 concentrations of the protein extract (80, 160, 200, and $240{\mu}g/mL$). Additionally, 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ODC activity decreased significantly in cells exposed to the extract in concentrations of $160{\mu}g/mL$ (p<0.05), $200{\mu}g/mL$ (p<0.005), and $240{\mu}g/mL$ (p<0.005). TPA-induced COX-2 activity also decreased in cells exposed to extract concentrations of 10, 20, 40, and $60{\mu}g/mL$. COX-2 expression was also inhibited in cells exposed to this extract. These results suggest that this protein extract of A pectinifera has chemopreventive activity in HT-29 human colon adenocarcinoma cells, and therefore, may have the potential to function as a chemopreventive agent in human colorectal cancer.