• Korean Journal of Environmental Biology
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• v.28 no.4
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• pp.196-201
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• 2010

The phenethyl ester of caffeic acid (CAPE), an active component of honeybee propolis extract, is shown to inhibit cancer growth previously. However, studies on human ovarian cancer are largely obscure. This study evaluated the effects of CAPE as a potential anti-proliferative and pro-apoptotic agent in the human ovarian cancer line, OVCAR-3. CAPE treated OVCAR-3 cells showed inhibition of cell viability and proliferation in a dose-dependent manner by WST-1 assay, LDH assay and bromodeoxyuridine (BrdU) incorporation assay. Furthermore, CAPE-mediated OVCAR-3 cell growth inhibition was associated with apoptotic changes as evident by cell cycle arrest and accumulation of cells in the apoptotic phase and DNA fragmentation. Taken together, CAPE inhibits cell proliferation via DNA synthesis reduction and induces apoptotic cell death via DNA damage, thus elucidating a novel, plausible mechanism of CAPE anti-tumorigenic property in OVCAR-3 cells.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.482-489
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• 2017

Individual differences in drug responses are associated with genetic and epigenetic variability of pharmacogene expression. We aimed to identify the relevant miRNAs which regulate pharmacogenes associated with drug responses. The miRNA and mRNA expression profiles derived from data for normal and solid tumor tissues in The Cancer Genome Atlas (TCGA) Research Network. Predicted miRNAs targeted to pharmacogenes were identified using publicly available databases. A total of 95 pharmacogenes were selected from cholangiocarcinoma and colon adenocarcinoma, as well as kidney renal clear cell, liver hepatocellular, and lung squamous cell carcinomas. Through the integration analyses of miRNA and mRNA, 35 miRNAs were found to negatively correlate with mRNA expression levels of 16 pharmacogenes in normal bile duct, liver, colon, and lung tissues (p<0.05). Additionally, 36 miRNAs were related to differential expression of 32 pharmacogene mRNAs in those normal and tumorigenic tissues (p<0.05). These results indicate that changes in expression levels of miRNAs targeted to pharmacogenes in normal and tumor tissues may play a role in determining individual variations in drug response.

• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.39-45
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• 1999

Human Carcinogenic Potency (HCP) can be estimated based on human daily exposure dose to carcinogen (Dh), body weight (Wh), 10% tumorigenic dose (TD10), and slope factor at TD10 (Q10) from 2-yr bioassay data. This approach is more relevant to humans generally exposed to low doses of carcinogens and can reduce more of extrapolation errors from high dose in animal experiments to low dose in humans than HERP (human exposure dose/rodent potency dose) proposed by Ames et al. (Science, 236, 271-280, 1987). TD50 and HERP have been routinely used to compare rodent carcinogenic potency and human carcinogenic potency, but those approaches have had limitations in extrapolation of high dose to low dose in humans. The advantages of HCP are to estimate human exposure dose (Dh) by human monitoring instead of environmental monitoring, to consider slope factor (Q10) which reflects the tendency of curve at low dose, and to use TD10 which represents much lower dose thant TD50 or HERP. HCP will be a useful parameter for the estimation of human carcinogenic potency in risk assessment and management of carcinogens.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.106-111
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• 2002

AG6O, the complex of acriflavine and guanosine, has been shown to possess the synergistic antitumorigenic activity in the previous paper (J. Pharm. Pharmacol. 1997, 49:216). In this study, we have investigated the genotoxic properties of AG60 using in vitro and in vivo system such as Ames bacterial reversion test, chromosomal aberration assay and micronucleus assay. In Ames reverse mutation test, AG60 treatment at the dose range up to 250 $\mu\textrm{g}$/plate caused the dose-independent random induction of the mutagenic colony formation in S. typhimurium TA98, TA100, TA1537, and E. coli WP2uvrA, while any mutagenic effect of AG60 wasn't observed in S. typhimurium TA1535. Any significant chromosomal aberration wasn't observed in chinese hamster lung (CHL) fibroblast cells incubated with PBS or AG60 at the concentrations of 2.5, 5, 10 $\mu\textrm{g}$/$m\ell$ for 24 hours without but even with 59 metabolic activation system for 6 hours. In vivo ICR mice, the intramuscular injection of AG60 at the doses of 7.15, 14.3, and 28.6 mg/kg did not induce the frequency of micronucleus formation. However, mitomycin C, as one of the positive controls at the dose of 2 mg/kg caused the 8.4% induction in the frequency of micronucleus and 24% increase in the chromosomal aberration.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.89-94
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• 2011

The potential biological activities of water and ethanol extracts from two varieties of Rubus coreanus Miquel fruits produced in the Gochang-gun (GR) and Hoengseong-gun (HR) regions of Korea were examined. The hydroxyl radical ($\cdot$OH) scavenging activity, reducing power, lipid peroxidation inhibitory activity, and antiproliferative activity on cancer cells by these extracts were examined, and $\alpha$-amylase and $\alpha$-glucosidase inhibition assays were also performed. The EtOH extract from GR showed high hydroxyl radical scavenging activity ($EC_{50}=119.47{\pm}5.13\;{\mu}g/mL$), lipid peroxidation inhibitory activity ($EC_{50}=213.45{\pm}3.14\;{\mu}g/mL$) and a concentration dependence, with OD values ranging from 0.15 to 0.56 (50 to 200 ${\mu}g/mL$), for reducing power. The EtOH extract from GR has the highest antiproliferative activities on MDA-MB-231 and HepG2 cancer cells among four extracts. Meanwhile, all extracts showed certain $\alpha$-amylase and $\alpha$-glucosidase inhibition activities. These results indicate that extracts from two varieties of R. coreanus fruits have significant antioxidant, anti-diabetic and anti-tumorigenic activities, which suggest these extracts could be a potential source for pharmaceutical.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.105-105
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• 2001

In an attempt to provide useful information on the development of an artifitial nerve tubing, proliferative and migrative properties of two glioma cell lines, C6 rat glioma cells and Hs683 human glioma cells, were examined. The present study shows that C6 cells proliferated more rapidly than Hs683 cells. The Hs683 cells are more adequate for the development of nerve tubing since unlike C6 cells, they are of human origin and known to be non-tumorigenic. In order to enhance proliferative and migrative abilities of Hs683 cells for the application as an artificial nerve tubing, we studied the effect of glial cell-derived neurotrophic factor (GDNF) on Hs683 cells. Cells were seeded in the scaffolds (polymer constructs), fabricated with type I collegen and alginate modified with cinnamoyl moiety, in the presence or absence of GDNF Stimulatory effect of GDNF on the proliferation and migration of Hs683 cells cultured in the scaffolds is currently under investigation. In addition, possible neuroprotective activities of natural products which inhibit staurosporine-induced apoptosis of glioma cells are also being studied.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5975-5979
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• 2012

Background: To investigate the influence of telomerase activity, apoptosis, radiosensitivity of cervical cancer after siRNA-mediated knockdown of telomerase RNA and evaluate in vivo growth with gene interference. Methods: We studied siRNA-targeting-telomerase RNA transfection into the Hela cell line. Expression of hTERC mRNA was detected by RT-PCR and telomerase activity was measured by the TRAP assay. Growth inhibition was determined by MTT assay and radiosensitivity of the cervical cancer cells was examined by colony formation assay. In addtion, effects of hTERC inhibition in vivo were studied by injection of siRNA-transfected Hela cells into nude mice. Results: The hTERC siRNA effectively downregulated the expression of hTERC mRNA and also reduced the telomerase activity to 30% of the untreated control vlaue. The viability of hTERC siRNA transfected Hela cells was reduced by 44.7% after transfection. After radiation treatment, the radiosensitivity of Hela cells with hTERC knockdown was increased. In vivo, the tumors developing from the hTERC siRNA-transfected cells were of reduced size, indicating that the hTERT siRNA also depressed the tumorigenic potential of the Hela cells. Conclusions: Our results supported the concept of siRNA-mediated inhibition of telomerase mRNA which could inhibit the expression of hTERC and telomerase activity. Furthermore, radiosensitivity was upregulated after knockdown the hTERC in vivo and in vitro.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.384-388
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• 2016

Reactive oxygen species are tumorigenic by their ability to increase cell proliferation, survival, and cellular migration. The purpose of the present study was to compare the antioxidant activity and cytotoxic effects of 3 berry extracts (strawberry, Korean raspberry, and mulberry) in A2780 human ovarian carcinoma cells. Except for raspberry, the ethyl acetate or methylene chloride fractions of berries containing phenolic compounds exerted dose dependent free radical scavenging activities. In the raspberry fractions, the hexane fraction also exhibited potent antioxidant activity. The cytotoxic effects of berries extracts in A2780 human ovarian carcinoma cells were measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Surprisingly, co-treatment with n-butanol (BuOH) fractions of berries showed stronger cytotoxic effects compared to the other fractions. These findings suggest that potent anticancer molecules are found in the BuOH fractions of berries that have stronger cytotoxic activity than antioxidants.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.875-880
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• 2015

Mediator 19 (Med19) is a component of the mediator complex which is a coactivator for DNA-binding factors that activate transcription via RNA polymerase II. Accumulating evidence has shown that Med19 plays important roles in cancer cell proliferation and tumorigenesis. The involvement of Med19 in sensitivity to the chemotherapeutic agent cisplatin was here investigated. We employed RNA interference to reduce Med19 expression in human non-small cell lung cancer (NSCLC) cell lines and analyzed their phenotypic changes. The results showed that after Med19 siRNA transfection, expression of Med19 mRNA and protein was dramatically reduced (p<0.05). Meanwhile, impaired growth potential, arrested cell cycle at G0/G1 phase and enhanced sensitivity to cisplatin were exhibited. Apoptosis and caspase-3 activity were increased when cells were exposed to Med19 siRNA and/or cisplatin. The present findings suggest that Med19 facilitates tumorigenic properties of NSCLC cells and knockdown of Med19 may be a rational therapeutic tool for lung cancer cisplatin sensitization.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5461-5465
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• 2013

Oral cancer is one of the most commonly occurring cancers worldwide, decreasing the patient's survival rate due to tumor recurrence and metastasis. Menadione (Vitamin K3) is known to exhibit cytotoxicity in various cancer cells but the present study focused on its effects on viability, apoptosis, epithelial to mesenchymal transition (EMT), anchorage independent growth and migration of oral cancer cells. The results show that menadione is more cytotoxic to SAS (oral squamous carcinoma) cells but not to non-tumorigenic HEK293 and HaCaT cells. Menadione treatment increased the expression of pro-apoptotic proteins, Bax and p53, with a concurrent decrease in anti-apoptotic proteins, Bcl-2 and p65. Menadione induced the expression of E-cadherin but reduced the expression of EMT markers, vimentin and fibronectin. Menadione also inhibited anchorage independent growth and migration in SAS cells. These findings reveal and confirm that menadione is a potential candidate in oral cancer therapy as it exhibits cytotoxic, antineoplastic and antimigratory effects besides effectively blocking EMT in oral cancer cells.