• 한국해양바이오학회지
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• 제1권4호
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• pp.243-251
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• 2006

Dideoxypetrosynol A, a polyacetylene from the marine sponge Petrosia sp., is known to exhibit significant selective cytotoxic activity against a small panel of human tumor cell lines, however, the mechanisms of which are poorly understood. In the present study, it was investigated the further possible mechanisms by which dideoxytetrosynol A exerts its anti-proliferative action in cultured human leukemia cell line U937. We observed that the proliferation-inhibitory effect of dideoxypetrosynol A was due to the induction of G1 arrest of the cell cycle and apoptosis, which effects were associated with up-regulation of cyclin D1 and down-regulation of cyclin E without any change in cyclin-dependent-kinases (Cdks) expression. Dideoxypetrosynol A markedly induced the levels of Cdk inhibitor p16/INK4a expression. Furthermore, down-regulation of phosphorylation of retinoblastoma protein (pRB) by this compound was associated with enhanced binding of pRB and the transcription factor E2F-1. The increase in apoptosis was associated with a dose-dependent up-regulation in pro-apoptotic Bax expression and activation of caspase-3 and caspase-9. Dideoxytetrosynol A decreased the levels of cyclooxygenase (COX)-2 mRNA and protein expression without significant changes in the levels of COX-1, which was correlated with a decrease in prostaglandin E2 (PGE2) synthesis. Furthermore, dideoxytetrosynol A treatment markedly inhibited the activity of telomerase, and the expression of human telomerase reverse transcriptase (hTERT), a main determinant of the telomerase enzymatic activity, was progressively down-regulated by dideoxytetrosynol A treatment in a dose-dependent fashion. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of dideoxytetrosynol A.

• Journal of Microbiology and Biotechnology
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• 제33권3호
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• pp.398-409
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• 2023

LncRNAs play crucial roles in the progression of colon adenocarcinoma (COAD), but the role of LINC01232 in COAD has not received much attention. The present study was designed to explore the related mechanisms of LINC01232 in the progression of COAD. LINC01232, miR-181a-5p, p53, c-myc, Bcl-2, cyclin D1, p16, Bax, VEGF, E-cadherin, vimentin, N-cadherin and SDAD1 expressions were determined by western blot and qRT-PCR. CCK-8, tubule formation, and Transwell assays were employed to detect proliferation, angiogenesis, and migration/invasion of COAD cells, respectively. The relationship between LINC01232 and miR-181a-5p was predicted by LncBase Predicted v.2, and then verified through dual luciferase reporter gene assay. According to the results, LINC01232 was highly expressed in COAD cells and enhanced proliferation, angiogenesis, migration, and invasion of COAD cells. Downregulated LINC01232 promoted expression of p53 and p16, and inhibited c-myc, Bcl-2 and cyclin D1 expressions in COAD cells, while upregulation of LINC01232 generated the opposite effects. LINC01232 was negatively correlated with miR-181a-5p while downregulated miR181a-5p could reverse the effects of siLINC01232 on cell proliferation, angiogenesis, migration, and invasion. Similarly, miR-181a-5p mimic could also offset the effect of LINC01232 overexpression. SiLINC01232 increased the expressions of Bax and E-cadherin, and decreased the expressions of VEGF, vimentin, N-cadherin and SDAD1, which were partially attenuated by miR-181a-5p inhibitor. Collectively, LINC01232 enhances the proliferation, migration, invasion, and angiogenesis of COAD cells by decreasing miR-181a-5p expression.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3041-3044
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• 2013

Background: The non-steroidal anti-inflammatory drug (NSAID) aspirin (acetylsalicylic acid) is an inhibitor of cyclooxygenase enzymes. Recent studies have shown that aspirin could be used as an anti-tumor drug. Triptolide, the major compound extracted from the Chinese herb Tripteryglum wilfordii Hook.f, has now been shown that it can inhibit tumor growth. The aim of this study was to analyze the anti-tumor efficiency of aspirin and triptolide in cervical cancer cells. Methods: Viability of cervical cancer cell lines was assessed by the MTT method at various concentrations of aspirin and triptolide. Siha and HeLa cell apoptotic analysis was performed by flow cytometry. Real time-PCR and Western Blotting were used to analyze the expression of Bcl-2/Bax, Cyclin D1 and p16. Results: Viability in the combination group was significantly decreased as compared with either drug used alone. Expression change of Bcl-2/Bax, CyclinD1 and p16 appeared to play an important role in the synergistic killing effect on cervical cancer cell apoptosis. Conclusion: Aspirin and triptolide combination treatment may have synergistic anti-tumor effects on cervical cancer cells.

• Journal of Periodontal and Implant Science
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• 제31권3호
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• pp.597-610
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• 2001

Normal gingival fibroblasts functioning is fundamental for the maintenance of periodontal connective tissue as well as wound healing. Nicotine have been found to affect DNA synthesis and cell proliferation, which appear to depend on the type of cells. This in vitro study was done to determine the effects of nicotine, a major component of tobacco, on cell proliferation, viability, activity, cell cycle distribution, and expression of cell cycle regulatory proteins in human gingival fibroblasts. Nicotine has been tested for 2 days or 4 days in 5 different concentrations; $0.1{\mu}g/ml$; $1{\mu}g/ml$; $10{\mu}g/ml$; $100{\mu}g/ml$; $1000{\mu}g/ml$. To assess cell proliferation and viability, viable and non-viable cells were counted by hemocytometer; to evaluate cellular activity, MTT assay was employed; to analyze cell cycle distribution, fluorescent propidium iodide-DNA complex were measured using fluorocytometer; to determine the expression of cell cycle regulatory proteins, western blot analysis was performed. After 2 days and 4 days incubation respectively, at concentrations of $1{\mu}g/ml$ - $1000{\mu}g/ml$, nicotine significantly inhibited proliferation comparing to non-supplemented controls. The cell viability was significantly decreased after 2 days and 4 days at concentrations of $1{\mu}g/ml$ - $1000{\mu}g/ml$ and at $10{\mu}g/ml$ - $1000{\mu}g/ml$ respectively. After 2 days and 4 days, the cellular activity was significantly decreased at concentrations of $10{\mu}g/ml$ - $1000{\mu}g/ml$. Treatment with $100{\mu}g/ml$ nicotine for 48 hours caused an increase in the proportion of G1-phase cells (from 46.41% to 53.46%) and a decrease in the proportion of S-phase cells (from 17.80% to 14.27%). The levels of cyclin $D_1$ and CDK 4 proteins in nicotine-treated fibroblasts were lower than that of controls, whereas the levels of p16 and pRB were higher than that of controls. These results suggest that the decrease of cell proliferation and lengthened Gap phases (G1) by nicotine may due to the increased expression of p16 and pRB as well as decreased expression of cyclin $D_1$ and CDK 4 in human gingival fibroblasts.

• Journal of Korean Neurosurgical Society
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• 제29권4호
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• pp.471-476
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• 2000

Objective : p16/INK4a, a kind of tumor suppressor genes, encodes a specific inhibitor of the cyclin D-dependent kinases CDK4 and CDK6. This prevents the association of CDK4 with cyclin D1, and subsequently inhibits phosphorylation of retinoblastoma tumor suppressor protein(pRb), thus preventing exit from the G1 phase. According to previous reports, over 50% of glioma tissue and 80% of glioma cell lines have been demonstrated inactivation of p16/INK4a gene. The purpose of this study was to determine whether recombinant adenovirus-p16 virus is a suitable candidate for gene replacement therapy in cases of glioma. Methods : Three human glioma cell lines(U251MG, U87MG and U373MG) that express mutant p16 protein were used. Replication-deficient adenovirus was utilized as an expression vector to transfer exogenous p16 cDNA into the cells ; control cells were infected with the Ad-${\beta}$-gal expressing ${\beta}$-galactosidase. To monitor gene transfer and the expression of exogenous genes, we used Western Blotting analysis. Flow cytometry studies of cellular DNA content were performed to determine the cell cycle phenotype of the glioma cells before and after treatment. Results : We showed here that restoration of p16/INK4a expression in p16 negative U87MG, U251MG and partially deleted U373MG by Ad-CMV-p16 induced growth suppression in vitro. Flow cytometric study revealed that Ad-CMV-p16 infected U87MG cells were arrested during the G0-G1 phase of the cell cycle. Expression of p16 transferred by Ad-CMV-p16 in glioma cells was highly efficient and maintained for more than seven days. Conclusions : Our results suggest that Ad-CMV-p16 gene therapy strategy is potentially useful and warrants further clinical investigation for the treatment of gliomas.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6977-6982
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• 2014

Background: The aim of this study was to investigate the effect of a Lipofectamine2000 (Life2000) Transfection Reagent transfected psiRNA-STAT3 plasmid on 4T1 breast cancer cells. Materials and Methods: MTT was used to detect the cell proliferation of breast cancer 4T1 cells at different periods (0h, 6h, 8h, 10h); the cell cycle was assessed by flow cytometry; variation of apoptosis and mitochondrial membrane potential was observed under a fluorescence microscope; immunohistochemical staining was used to determine the expression of caspase-3 and cyclin-D1 protein. Results: An obvious effect of inhibition to 4T1 cancer cells could be observed at 8h after the psiRNA-STAT3 was transfected. Typical alterations of apoptotic morphological features were visible in the psiRNA-STAT3 treatment group. Mitochondrial membrane potential decreased significantly, the number of cells was increased in G0/G1 phase, and the number of cells was decreased in S phase, and the data were statistically significant (p<0.05), compared with the Scramble and Mock groups. Expression of caspase-3 protein was increased significantly, while that of cyclin D1 was significantly decreased. Conclusions: Life2000 transfected psiRNA-STAT3 plasmid can inhibit 4T1 tumor cell proliferation and promote apoptosis of 4T1 tumor cells, which process depends on the regulation of expression of cyclin D1 and caspase-3 protein.

• 동의생리병리학회지
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• 제21권1호
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• pp.204-208
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• 2007

Chaga mushroom extract is well known as immune modulator and anti-cancer agent. However, the molecular mechanism by which Chaga exerts cell cycle arrest and apoptosis of cancer cells is poorly understood. In this study, we demonstrated anti-proliferative effects of Chaga extract on murine melanoma B16 cells. Chaga extract dose-dependently inhibited cell growth along with the arrest of G0/G1 phase and the induction of apoptotic cell death. Treatment with Chaga extract resulted in a decrease of cyclin E, cyclin D1, cdk 2, cdk 4 expression levels. Furthermore, in vivo inoculation study of B16 melanoma cells into Balb/c mice Chaga extract markedly suppressed the metastatic growth of tumor cells (6 folds, p<0.05,). These results indicate that Chaga mushroom extract induces apoptosis of B16 melanoma cells through arrest of G0/G1 phase in cell cycle.

• Journal of Periodontal and Implant Science
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• 제33권3호
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• pp.415-437
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• 2003

Ginseng Radix(GR) had been used widely from oriental medicine and the effects of it have been investigated by many researchers. The purpose of present study was to investigate the effects of GR on the cell cycle progression and its molecular mechanism in human fetal osteoblast. The results were as follows. Increased cell proliferation was observed in cells exposed to 100 ng/ml, 10 ng/ml of GR-1 at 12 hours and 24 hours, 1 ${\mu}g$/ml of GR-1 at 48 hours, and 100 ${\mu}g$/ml, 10 ${\mu}g$/ml of GK-2 at 12 hours, all treatment groups of GR-2 at 24 hours(p<0.05). S phase and G1 phase was increased in the group of treated with 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, with 100 ${\mu}g$/ ml and 10 ${\mu}g$/ml of GR-3 in the cell cycle analysis. The cell cycle regulation protein levels of Cyclin D1, Cyclin E, CDK 2. CDK 4 and CDK 6 were increased in the group of treated with 1 ${\mu}g$/ml and 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, with 100 ${\mu}g$/ ml and 10 ${\mu}g$/ml of GR-3. On the other hand, p21 was decreased in the treatment group with 1 ${\mu}g$/ml and 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, 10 ${\mu}g$/ml of GR-3, and p53 and p16 was decreased in the treatment group with 100 ng/ml of GR-1, 100 ${\mu}g$/ml and GR-3 and pRb was decreased in the all treatment groups except 1 ${\mu}g$/ml of GR-1. These results suggested that GR increases the cell proliferation and the cell cycle progression in human fetal osteoblast, which is linked to increased cell cycle regulation protein levels of Cyclin D1 , Cyclin E, CDK 2, CDK 4, CDK 6 and decreased cell cycle regulation protein levels of p21, pRb.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8113-8117
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• 2016

Glehnia littoralis (GL) is widely used as an oriental medicine for cough, fever, stroke and other disease conditions. However, the anti-cancer properties of GL on MCF-7 human breast cancer cells have not been investigated. In order to elucidate anti-cancer properties and underlying cell death mechanisms, MCF-7cells ($5{\times}10^4/well$) were treated with Glehnia littoralis root extract at 0-400 ug/ml. A hot water extract of GL root inhibited the proliferation of MCF-7 cells in a dose-dependent manner. Analysis of the cell cycle after treatment of MCF-7 cells with increasing concentrations of GL root extract for 24 hours showed significant cell cycle arrest in the G1 phase. RT-PCR and Western blot analysis both revealed that GL root extract significantly increased the expression of p21 and p27 with an accompanying decrease in both CDK4 and cyclin D1. Our reuslts indicated that GL root extract arrested the proliferation of MCF-7 cells in G1 phase through inhibition of CDK4 and cyclin D1 via increased induction of p21 and p27. In summary, the current study showed that GL could serve as a potential source of chemotherapeutic or chemopreventative agents against human breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2939-2946
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• 2015

Many of the anti-cancer agents currently used have an origin in natural sources including plants. Aloe vera is one such plant being studied extensively for its diverse health benefits, including cancer prevention. In this study, the cytotoxic potential of Aloe vera crude extract (ACE) alone or in combination with cisplatin in human breast (MCF-7) and cervical (HeLa) cancer cells was studied by cell viability assay, nuclear morphological examination and cell cycle analysis. Effects were correlated with modulation of expression of genes involved in cell cycle regulation, apoptosis and drug metabolism by RT-PCR. Exposure of cells to ACE resulted in considerable loss of cell viability in a dose- and time-dependent fashion, which was found to be mediated by through the apoptotic pathway as evidenced by changes in the nuclear morphology and the distribution of cells in the different phases of the cell cycle. Interestingly, ACE did not have any significant cytotoxicity towards normal cells, thus placing it in the category of safe chemopreventive agent. Further, the effects were correlated with the downregulation of cyclin D1, CYP 1A1, CYP 1A2 and increased expression of bax and p21 in MCF-7 and HeLa cells. In addition, low dose combination of ACE and cisplatin showed a combination index less than 1, indicating synergistic growth inhibition compared to the agents applied individually. In conclusion, these results signify that Aloe vera may be an effective anti-neoplastic agent to inhibit cancer cell growth and increase the therapeutic efficacy of conventional drugs like cispolatin. Thus promoting the development of plant-derived therapeutic agents appears warranted for novel cancer treatment strategies.