• Journal of Food Hygiene and Safety
• /
• v.26 no.2
• /
• pp.150-153
• /
• 2011

Betulinic acid (BA), a naturally occurring triterpene found in the bark of the white birch tree, has been investigated to induce apoptosis in various cancer cells and animal models. However, there is no report of the chemopreventive effect of BA in cervical cancer cells. Using KB human cervical cancer cells as a model, we currently show that BA decreases cell viability and induces apoptotic cell death. The mechanism of the BA-induced anti-growth response in KB cells is due to the down-regulation of specificity protein 1 (Sp 1) and its downstream targets, myeloid cell leukemia-1(Mcl-1) and survivin. Thus, BA acts as a novel chemopreventive agent through the regulation of Sp1 that is highly expressed in tumors.

• International Journal of Oral Biology
• /
• v.35 no.4
• /
• pp.215-220
• /
• 2010

Angelica decursiva has been used in Korean traditional medicine as an antitussive, an analgesic, an antipyretic and a cough remedy. However, its anti-cancer properties have not yet been well defined. In our current study, we report the cytotoxic activity and the mechanism of cell death induced by ethanol extracts of Angelica decursiva (EEAD) against the human oral cancer cell line, KB. Treatment of KB cells with EEAD induced apoptotic cell death in both a dose- and time-dependent manner as determined by MTT assay and DNA fragmentation. However, no cytotoxic effects of EEAD against human normal oral keratinocytes (HNOK) were evident. By western blot analysis, we found that apoptosis in KB cells is associated with a decrease in procaspase-7 and -9. In addition, the activation of caspase-7 was detectable in living KB cells by fluorescence microscopy. These results suggest that EEAD exhibits anti-cancer activity in KB cells via apoptosis and thus has potential as an anticancer agent in future drug development strategies.

• Macromolecular Research
• /
• v.14 no.6
• /
• pp.646-653
• /
• 2006

Highly hydrophilic, uniform, superparamagnetic and nontoxic maltotrionic acid (MA)-coated magnetite nano-particles (MAM) were prepared and characterized by TEM, DLS, XRD and VSM. MA was used to improve the biocompatibility, monodispersity and non-specific intracellular uptake of nanoparticles. Folic acid (FA) was subsequently conjugated to the MAM to preferentially target KB cells (cancer cells) that have folate receptors expressed on their surfaces and to facilitate nanoparticles in their transit across the cell membrane. Finally, fluorescence isothiocyanate (FITC) was added to the nanoparticles to visualize the nanoparticle internalization into KB cells. After the cells were cultured in a media containing the MAM and MAM-folate conjugate (FAMAM), the results of fluorescence and confocal microscopy showed that both types of nanoparticles were internalized into the cells. Nevertheless, the amount of FAMAM uptake was higher than that of MAM. This result indicated that nanoparticles modified with MA and FA could be used to facilitate the nanoparticle uptake to specific KB cells (cancer cells) for molecular imaging.

• Journal of dental hygiene science
• /
• v.10 no.5
• /
• pp.365-372
• /
• 2010

Caesalpinia sappan L. has long been commonly used in oriental folk medicines and as dyes materials. To investigate the antioxidative activities and antiproliferation effects of brazilin from C. sappan heart wood, the MeOH soluble extract was successively fractionated by using hexane, $CHCl_{3}$, EtOAc, BuOH, MeOH, and $H_{2}O$. In these fractions, we were purified brazilin from EtOAc fraction which partitioned to 3.94% of the highest yields. The effects of brazilin and the extracts on human oral carcinoma cells (KB) by MTT assay and their antioxidant activities by DPPH, TCA assay and Fenton reaction were tested. The results showed that the brazilin could inhibits the proliferation of KB cells and obviously decreased the production of nitric oxide of the cells. When the concentration of the brazilin reached to $100\;{\mu}g/ml$, the inhibition percentage of the cell growth was about 60%. In assay on antioxidant activities, The results showed that brazilin exhibit the highest capacity of DPPH free radical scavenging effects among tested extracts. When the concentration of brazilin reached to 1 mg/ml, the lipid peroxide inhibition and radical inhibition activities were determined to be 65.0% and 85.8%, respectively. These results are suggest that brazilin have stronger antiproliferation effect on KB cell and antioxidant properties.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.29 no.2
• /
• pp.435-449
• /
• 1999

Purpose : The study was aimed to detect the differences in the cell viability and the apoptosis induction after irradiation on normal and tumorigenic cells. Materials and Methods : The study. that was generated for two human normal cells(RHEK, HGF-l) and two human tumor cells(KB. HT-1080). was tested using MTT assay at 1 day and 3 day after irradiation and TUNEL assay under confocal laser scanning microscope at 1 day after irradiation. Single irradiation of 0.5. 1, 2. 4. and 8Gy were applied to the cells. The two fractions of 1. 2. 4. and 8Gy were separated with a 4-hour time interval. The irradiation was done with 5.38Gy/min dose rate using Cs-137 irradiator at room temperature. Results and Conclusions : 1. In 3-day group. the cell viability of HGF-1 cell was significantly decreased at 2. 4 and 8Gy irradiation, the cell viability of KB cell was significantly decreased at 8Gy irradiation and the cell viability of HT-I080 cell was significantly decreased at 4 and 8Gy irradiation. 2. There was significant difference between RHEK and KB cell line in the cell viability of 3-day group at 8Gy irradiation. There was significant difference between RHEK and HGF-1 cell line in the cell viability of 3-day group at 4 and 8Gy irradiation. 3. There was a significantly decreased cell viability in 3-day group than those in 1-day group at 2. 4 and 8Gy on HGF-1 cell. at 4 and 8Gy on HT-I080 cell. at 8Gy on KB cell. 4. We could detect DNA fragmented cells only on KB cell. Number of apoptotic cells of KB cell was significantly increased at 4 and 8Gy irradiation. However, there was no correlation between cell viability and apoptosis. 5. On all 4 cell lines, there were no differences between single and split irradiation method in cell viability and apoptosis.

• International Journal of Oral Biology
• /
• v.32 no.4
• /
• pp.127-133
• /
• 2007

Oral squamous cell carcinoma (OSCC) is the most common malignancy and is a major cause of worldwide cancer mortality. The proto-oncogene c-myb plays an important role in regulation of cell growth and differentiation, and it is expressed at high levels in hematopoietic cells and many other types of cancers. However, the function of c-myb is not well known in OSCC. The present study aimed to reveal the function of c-myb and to test the alternation of cell growth and signaling by c-myb in OSCC. In this study, c-myb and dominant-negatibe myb(DNmyb) were expressed in an adenovirus-mediated gene delivery system to KB cells. The over-expressed c-myb brought increased cellular proliferation compared with control cells. However, DN-myb infected KB cells showed significant reduction of cell growth and enhanced induction of apoptosis to activate PARP and caspase 9. c-myb induced increase of IGF-I, -II and IGF-IR expressions while DN-myb down-regulated these expression. Activation of ERK and Akt/PKB pathway was shown only in c-myb transduced cells. These findings suggest that the role of c-myb in cell growth of oral cancer cells is partially mediated through the modulation of IGFs, ERK and Akt/PKB. From this results, DN-myb is strongly recommended as a curable gene for the treatment of c-myb dependent malignancies such as OSCC.

• Environmental Mutagens and Carcinogens
• /
• v.18 no.2
• /
• pp.104-108
• /
• 1998

In the present study, we have evaluated cytotoxic effects of Taraxaci Herba extract in human oral epitheloid carcinoma cells. An antitumor activity was measured by colorimetric assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and sulforhodamine protein B (SRB). The light microscopic study showed morphological changes, Ag-NOR (argyrophylic nucleolar organizer region) number and PAS positive reaction or the treated cells. These results obtained are as follows : MTT and SRB quantities were significantly decreased in cultured KB cells treated with 10$^{-2}$ /mg/ml and 10$^{-3}$ /mg/ml concentrations. The number of Ag-NORs were significantly decreased in cultured KB cells treated with 10$^{-2}$ /mg/ml and 10$^{-3}$ /mg/ml concentrations and the rate of Ag-NORs was shifted to left side (one Ag-Nounucleus was increased and five Ag-NORs/nucleus were decreased) by the high concentration. PAS reaction of cultured KB cells treated with 10$^{-2}$ /mg/ml and 10$^{-3}$ /mg/ml concentrations was negative. These results suggest that Taraxaci Herba retains a potential antitumor activity.

• Biomolecules & Therapeutics
• /
• v.5 no.3
• /
• pp.265-271
• /
• 1997

Since the advent of chemotherapy, certain types of cancer have been particularly resistant to chemotherapeutic treatment. One of the most well-studied types of resistance is resistance to multiple struc-turally dissimialr hydrophobic chemotherapeutic agents, or multidrug resistance (MDR). We found that MDR cells (KBV20C, KB7D) being highly resistant to colchicine, etoposide, and vincristine were found to have very low level of putrescine and low level of spermidine than the drug sensitive parental cells (KB) but they had almost same level of spermine as the drug sensitive cells. Although both MDR and drug sensitive cells had almost same rate of polyamine uptake, MDR cells were much more sensitive to an inhibitor of polyamine synthesis, methylglyoxal-bis guanylhydrazone (MGBG), suggesting that MDR cells might be defective in polyamine synthesis. These results also suggest that HGBG can be used for treatment of MDR in vivo.

• Journal of Environmental Health Sciences
• /
• v.31 no.5 s.86
• /
• pp.444-450
• /
• 2005

The present study was designed to investigate whether traditional Korean fermented soybean paste(doen-jang) and soybean extracts have inhibitory effects on the growth of KB cell, an oral epithelioid cancer cell. When KB cell ATCC CCL-17 was cultivated for 48 flours with the addition of 0.5% of the five types or doen-jang extract, the growth of KB cell was inhibited by all types of extract, and ethyl acetate extract showed the highest inhibitory effect. In case of soybean extract, all types of extract also showed KB cell inhibitory effects, however, generally less than those of doen-jang extract. When ethyl acetate extract of doen-jang was added in different concentrations and KB cell was cultivated for 24 hours and 45 hours, strong inhibitory effect began to appear from the concentration of 1.25 mg/ml. Although soybean extract showed such a tendency, its effect was lower than that of doen-jang extract. These results indicate that doen-jang extract has inhibitory effect against KB cell, and particularly ethyl acetate extract has the highest effect. The effect of doen-jang extract might be possibly enhanced by the fermentation of soybeans. It is assumed that doen-jang extract may be used to develop nontoxic medicines for preventing and treating oral diseases.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.28 no.1
• /
• pp.271-283
• /
• 1998

The purpose of this study was to aid in the prediction of tumor cell tolerance to radiotherapy and/or chemotherapy. For this study, cell surviving curves were obtained for human squamous cell carcinoma KB cell line after radiation exposure and/or administration of antitumor drugs. 2, 4, 6, 8, 10Gy were irradiated at a dose rate of 210cGy/min using /sup 60/Co Irradiator ALDORADO 8. After irradiation, KB cell lines (3×104cells/ml) were exposed to 2㎍/ml of bleomycin or cisplatin for 1 hour. The viable cells were determined by MTT assay for each radiation dose and/or each drug at the 4th day. And they were compared to control values. The obtained results were as follows : 1. The slope of the surviving curve after irradiation of 2, 4, 6, 8, 10Gy on KB cell line was relatively steep. 2. There was no significant difference between the cytotoxicity of bleomycin compared to control group. But, there was significant difference between the cytotoxicity of cisplatin compared to control group. And the cytotoxicity of cisplatin was greater than that of bleomycin on KB cell line. 3. There were significant differences of surviving fractions after irradiation of 2Gy and 10Gy with 2㎍/ml of bleomycin compared with the groups of irradiation only on KB cell line. 4. There were significant differences of surviving fractions after irradiation of 2, 4, 6, 8, 10Gy with 2㎍/ml of cisplatin compared with the groups of irradiation only on KB cell line. 5. There was significant difference of surviving fraction between groups after irradiation of 10Gy with 2㎍/ml of bleomycin and cisplatin.