• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.109-110
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• 2003

To validate a novel mouse model, gpt delta, for in vivo mutagenesis, the Mammalian Mutagenesis Society (MMS), a subgroup of the Environmental Mutagen Society of Japan (JEMS) (JEMS/MMS), performed a collaborative study as the third trial for transgenic animal assay. In this mouse model, point mutations and deletions re separately identified by gpt (6-thioguanine-resistant) and Spi- (sensitive to P2 interference) selections, respectively.(omitted)

• Proceedings of the KOR-BRONCHOESO Conference
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• 2007.05a
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• pp.40-40
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• 2007

• 대한생식의학회:학술대회논문집
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• 2006.11a
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• pp.144-145
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• 2006

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.352.2-352
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• 1995

No Abstract, See Full Text

• Animal cells and systems
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• v.1 no.3
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• pp.451-455
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• 1997

The effects of nalidixic acid, mitomycin C, and cadmium chloride $(CdCI_2)$ on the activity of 8-hydroxyguanine $(oh^8Gua)$ endonuclease, a DNA repair enzyme for oxidatively modified guanine, $(oh^8Gua$ were studied. Nalidixic acid and mitomycin C, typical inducers of the S0S DNA repair response in E. coli, showed different effects. Nalidixic acid raised the activity of this enzyme, but mitomycin C did not show such an effect. Cadmium chloride also induced the enzyme activity, These results show that the expression of $oh^8$ Gua endonuclease is regulated by multiple factors and can be induced under stressful conditions. In an attempt to demonstrate the importance of this enzyme in defense against DNA damage and mutagenesis, we also characterized mutM mutant for its oh8 Gua endonuclease activity. The mutM mutant showed no detectable $oh^8$ Gua endonuclease activity, unlike its wild type showing high activity. In addition, paraquat, a superoxide producing compound, failed to elevate $oh^8Gua$ endonuclease activity in this mutant. These results suggest that the mutM gene is identical to the $oh^8Gua$ endonuclease gene of E. coli. Taken together with previous reports, these results suggest that $oh^8Gua$ endonuclease plays a crucial role in the protection of aerobically growing organisms from threats of oxidative DNA damage and mutation.

• Environmental Mutagens and Carcinogens
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• v.21 no.1
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• pp.51-56
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• 2001

Kimchi is a major Korean traditional fermented food, as a supplying source of vitamin and minerals which is prepared with various vegetables and condiments such as red pepper, garlic and salted fish etc. There are many types of Kimchi depending on the ingredients and preparation methods used. To investigate the clastogenicity and anticlastogenicity of Baechu (Chinese cabbage) Kimchi and Buchu (leek, Allium odorum) Kimchi in mouse, it was performed acridine orange supravital staining of micronucleus (AOSS-MN) assay using mouse peripheral reticulocytes. Baechu Kimchi and Buchu Kimchi were cultivated by organic agricultural technique, and Kimchi samples were prepared by methanol extraction and lyophilization. First of all, it was studied the clastogenicity of two Kimchi samples themselves (250-1,000 mg/kg) after oral adminstration in mouse. And also to study the anticlastogenic effect of oral administration of Kimchi samples, mitomycin C (MMC, 1 mg/kg, i.p.) was used as micronucleus inducing agent in this study. Dosing scheme was performed as simultaneous (co-treatment), 3 hr before (pre-treatment) and 3 hr after (post-treatment) with MMC treatment. Two Kimchi samples in the range of 250-1,000 mg/kg did not reveal any clastogenic effect in AOSS-MN assay in mouse. They also revealed anticlastogenic effects in post-treatment of Baechu Kimchi (1,000 mg/kg), and in pre-treatment of Buchu Kimchi (500 and 1,000 mg/kg) with statistical significance. The anticlastogenic effect revealed 1 and 6 hr after treatment of Baechu Kimchi, and Buchu Kimchi with 3 and 6 hr pretreatment. Consequently, it is suggested that antimutagenic and anticlastogenic mechanisms of Baechu and Buchu Kimchi in vivo attributed to sipindle formation and kinetic behavior of mutagens such as absorption and metabolism etc.

• Molecular & Cellular Toxicology
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• v.3 no.3
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• pp.165-171
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• 2007

Mitomycin C (MMC), an antitumor antibiotic isolated from Streptomyces caespitosus, is used in chemotherapy of gastric, bladder and colorectal cancer. MMC is activated in vivo to alkylate and crosslink DNA, via G-G interstrand bonds, thereby inhibiting DNA synthesis and transcription. This study investigates gene expression changes in response to MMC treatment in order to elucidate the mechanisms of MMC-induced toxicity. MMC was admistered with single dose (0.32 and 1.6 ${\mu}M$) to TK6 cells. Applied Biosystem's DNA chips were used for identifying the gene expression profile by MMC-induced toxicity. We identified up- or down-regulated 90 genes including cyclin M2, cyclin-dependent kinase inhibitor 1A (p21, cip1), programmed cell death 1, tumor necrosis factor (ligand) superfamily, member 9, et al. The regulated genes by MMC associated with the biological pathways apoptosis signaling pathway. Further characterization of these candidate markers related to the toxicity will be useful to understand the detailed mechanism of action of MMC.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3241-3245
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• 2015

Purpose: To examine the effectiveness of mitomycin-C and chemo-hyperthermia in combination for patients with high-risk non-muscle-invasive bladder cancer. Materials and Methods: Between November 2011-September 2013, 43 patients with high-risk non-muscle-invasive bladder cancer undergoing adjuvant chemo-hyperthermia in two centers were evaluated retrospectively. Treatment consisted of 6 weekly sessions, followed by 6 sessions. Recurrence and progression rate, recurrence-free interval and side effects were examined. Analyzed factors included age, gender, smoking status, AB0 blood group, body mass index, T stage and grade, concominant CIS assets. The associations between predictors and recurrence were assessed using multivariate Cox proportional hazard analyses. Results: A total of 40 patients completed induction therapy. Thirteen (32.5%) were diagnosed with tumor recurrence. Median follow-up was 30 months (range 9-39). Median recurrence-free survival was 23 months (range 6-36). The Kaplan-Meier-estimated recurrence-free rates for the entire group at 12 and 24 months were 82% and 61%. There was no statistically significant difference between patient subgroups. Cox hazard analyses showed that an A blood type (OR=6.23, p=0.031) was an independent predictor of recurrence-free. Adverse effects were seen in 53% of patients and these were frequently grades 1 and 2. Conclusions: Intravesical therapy with combination of mitomycin-C and chemohyperthermia seems to be appropriate in high-risk patients with non-muscle-invasive bladder cancer who cannot tolerate or have contraindications for standard BCG therapy.

• Journal of Life Science
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• v.14 no.2
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• pp.209-214
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• 2004

Cytotoxic anticancer chemotherapeutic agents generally produce severe side effects, while reducing host resistance to cancer and infections, especially through the destruction of lymphoid and bone marrow cells. In this study, we have investigated the effect of chitosan on cytotoxic activity against cancer cells and life span in mice. The direct cytotoxicity of chitosan or chitosan-combinated chemotherapeutic agents for tumor cells was observed. In addition, the effect of life span extention was counted on sarcoma 180 mice injected with chitosan-combinated mitomycin C. The effect of growth inhibion for cancer cells, K562 and Yac-1 was shown in the cytotoxicity test of chitosan or chitosan-combinated chemotherapeutic agents. Also, the effect of life span extension was observed on sarcoma 180 mice injected with chitosan-combinated mitomycin C. Our results suggest that life span extension in sarcom 180 mice exposed with chitosan-combinated chemotherapeutic agents showed the probability of its usefulness for cancer therapy if more research results were accumulated.

• Korean Journal of Pharmacognosy
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• v.23 no.3
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• pp.158-170
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• 1992

The studies were conducted to investigate the combined effects of several combined preparation of crude drugs and mitomycin C(MMC). The combined effects on the proliferation of Molt-4 cells and activation of human lymphocytes were estimated by MTT colorimetric assays. The drugs itself enhanced the proliferation of Molt-4, but the inhibitory action of MMC was not affected by the combined treatment of the drugs and MMC. Among 9 kinds of the drugs, Sip Jeon Dae Bo Tang(SDT), Saeng Maek San(SMS) and Kwi Bi Tang(KBT) did not inhibit the action of MMC, but activated lymphocytes. When the mice were treated by MMC, the number of leukocytes was decreased significantly at the 1st day, but recovered at the 7th day. In the groups of MMC treated with SDT or KBT, the number of leukocytes was increased significantly than the group of MMC treated only at the 3rd day. The combined treatment of SDT, SMS and MMC retained the body weight of mice at the level of normal mice. The SDT, SMS and KBT did not change the number of plaque forming cells(PFC) and the proliferation of T cells. The combined treatment of SDT and MMC increased the number of PFC significantly than the MMC treated group. The combined treatment of SDT, SMS, KBT and MMC increased the T cell proliferation significantly than the MMC treated group. In conclusion, it is suggested that SDT, SMS and KBT can recover the side effects of MMC, such as weight loss, leukopenia and immunosuppression, without any intercalating the anti-proliferative action of MMC in vivo.