• Journal of Nutrition and Health
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• v.47 no.1
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• pp.1-11
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• 2014

Purpose: Several studies have proven that EGCG, the primary green tea catechin, and glucosamine-6-phosphate (PGlc) reduce triglyceride contents in 3T3-L1 adipocytes. The objective of this study is to evaluate the combination effect of EGCG and PGlc on decline of accumulated fat in differentiated 3T3-L1 adipocytes. Methods: EGCG and PGlc were administered for 6 day for differentiation of 3T3-L1 adipocytes. Cell viability was measured using the CCK assay kit. In addition, TG accumulation in culture 3T3-L1 adipocytes was investigated by Oil Red O staining. We examined the expres-sion level of several genes and proteins associated with adipogenesis and lipolysis using real-time RT-PCR and Western blot analysis. A flow cytometer Calibar was used to assess the effect of EGCG and PGluco on cell-cycle progression of differentiating 3T3-L1 cells. Results: Intracelluar lipid accumulation was significantly decreased by combination treatment with EGCG $60{\mu}M$ and PGlc $200{\mu}g/m$ compared with control and EGCG treatment alone. In addition, use of combination treatment resulted in directly decreased expression of $PPAR{\gamma}$, $C/EBP{\alpha}$, and SREBP1. In addition, it inhibited adipocyte differentiation and adipogenesis through downstream regulation of adipogenic target genes such as FAS, ACSL1, and LPL, and the inhibitory action of EGCG and PGlc was found to inhibit the mitotic clonal expansion (MCE) process as evidenced by impaired cell cycle entry into S phase and the S to G2/M phase transition of confluent cells and levels of cell cycle regulating proteins such as cyclin A and CDK2. Conclusion: Combination treatment of EGCG and PGlc inhibited adipocyte differentiation through decreased expression of genes related to adipogenesis and adipogenic and cell cycle arrest in early stage of adipocyte differentiation.

• BMB Reports
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• v.42 no.11
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• pp.725-730
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• 2009

Cyclin E1 (CCNE1), a positive regulator of the cell cycle, controls the transition of cells from G1 to S phase. In numerous human tumors, however, CCNE1 expression is frequently dysregulated, while the mechanism leading to its dysregulation remains incompletely defined. Herein, we showed that CCNE1 expression was subject to post-transcriptional regulation by a microRNA miR-16-1. This was evident at protein level of CCNE1 as well as its mRNA level. Further evident by dual luciferase reporter assay revealed that two evolutionary conserved binding sites on 3' UTR of CCNE1 were the direct functional target sites. Moreover, we showed that miR-16-1 induced G0/G1 cell cycle arrest by targeting CCNE1 and siRNA against CCNE1 partially phenocopied miR-16-1-induced cell cycle phenotype whereas substantially rescued anti-miR-16-1- induced phenotype. Together, all these results demonstrate that miR-16-1 plays a vital role in modulating cellular process in human cancers and indicate the therapeutic potential of miR-16-1 in cancer therapy.

• Biomedical Science Letters
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• v.23 no.3
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• pp.290-294
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• 2017

Metformin or sodium salicylate is known to induce apoptosis and G0/G1 phase arrest in a variety of cancer cells. However, the anti-cancer effects of the combined treatments for these drugs-induced apoptosis are yet unclear. Here, we found that the combined treatment of metformin and sodium salicylate increased the efficacy of chemotherapeutics against breast cancer cells. These combined drugs significantly inhibited cellular proliferation and induced apoptosis at an earlier stage in human MCF-7 breast cancer cells. Also, co-treatments of metformin and sodium salicylate induced G1 cell cycle arrest in MCF-7 cells more effectively than either agent alone. Taken together, these results demonstrate that dual metformin/sodium salicylate treatment prevents proliferation of MCF-7 cells by inducing apoptosis and G1 cell cycle arrest.

• Biomolecules & Therapeutics
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• v.16 no.1
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• pp.21-27
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• 2008

Clotrimazole (CLT), a potent antifungal drug, is known to inhibit tumor cell proliferation. In the present study, we examined the role of intracellular $Ca^{2+}$ in CLT-induced cell cycle arrest of colon adenocarcinoma HT29 cells. CLT inhibited growth of HT29 cells in a concentration-dependent manner, which was associated with inhibition of cell cycle progression at the G(1)-S phase transition and an increase in the expression of cell cycle inhibitor proteins p27 and p53. CLT also suppressed the $Ca^{2+}$ overload by A23187, a calcium ionophore, suggesting its role in modulation of intracellular $Ca^{2+}$ concentration in HT29 cells. The simultaneous application of CLT and A23187 with addition of $CaCl_2$ (1mM) to the medium significantly reversed CLT-induced p27 and p53 protein level increase and growth suppression. Our results suggest that CLT induces cell cycle arrest of colon adenocarcinoma HT29 cells via induction of p27 and p53, which may, at least in part, be mediated by alteration of intracellular $Ca^{2+}$ level.

• Biomolecules & Therapeutics
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• v.20 no.2
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• pp.177-182
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• 2012

Tetrazolium violet is a tetrazolium salt and has been proposed as an antitumor agent. In this study, we reported for the first time that tetrazolium violet not only inhibited human lung cancer A549 cell proliferation but also induced apoptosis and blocked cell cycle progression in the G1 phase. The results showed that tetrazolium violet significantly decreased the viability of A549 cells at $5-15{\mu}M$. Tetrazolium violet -induced apoptosis in A549 cells was confirmed by H33258 staining assay. In A549, tetrazolium violet blocked the progression of the cell cycle at G1 phase by inducing p53 expression and further up-regulating p21/WAF1 expression. In addition, an enhancement in Fas/APO-1 and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), as well as caspase, were responsible for the apoptotic effect induced by tetrazolium violet. The conclusion of this study is that tetrazolium violet induced p53 expression which caused cell cycle arrest and apoptosis. These findings suggest that tetrazolium violet has strong potential for development as an agent for treatment lung cancer.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.463-468
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• 2002

We have previously reported on the identification of the endogenous transmethylation inhibitor oligosaccharide-linked acyl carrier protein (O-ACP), In this study, the role of the transmethylation reaction on cell cycle progression was evaluated using various transmethylase inhibitors, including O-ACP. O-ACP significantly inhibited the growth of various cancer cell lines, including NIH3T3, ras-transformed NIH3T3, MDA-MB-231, HT-1376, and AGS. In addition, exposure of ras-transformed NIH3T3 to O-ACP caused cell cycle arrest at the $G_0/G_1$ phase, which led to a decrease in cells at the S phase, as determined by flow cytometry. In contrast, transmethylase inhibitors did not affect the expression of $p21^{WAF1/Cip1}$, a well known inhibitor of cyclin dependent kinase, indicating that the cell cycle arrest by transmethylase inhibitors might be mediated by a $p21^{WAF1/Cip1}$-independent mechanism. Therefore, O-ACP, a novel transmethylase inhibitor, could be a useful tool for elucidating the novel role of methylation in cell proliferation and cell cycle progression.

• Herbal Formula Science
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• v.32 no.2
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• pp.181-191
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• 2024

Objective : Inulae Flos(IF) has been used to treat arthritis, sever furuncle, fear and palpitation, vomiting, stroke, asthma and cough in Korean Medicine. Although the anticancer activity of IF has been reported, the molecular mechanism is still not well understood. In this study, we investigated the growth inhibitory activity of an ethanol extract of IF in HT-1080 human fibrosarcoma cells and its underlying mechanisms using two-dimensional (2D) and three-dimensional (3D) cell culture system. Methods : HT-1080 cells were cultured with IF for 9 days in 3D cell culture. To check an inhibition of cell prolifelation by IF, MTT assay was performed. DNA contents were measured using flow cytometry. Western blotting was used to evaluate the regulation of cell cycle- and autophagy-related proteins. Acridine orange staining was performed to confirm autophagy, and DCF-DA staining was performed to confirm the occurrence of ROS. Results : IF controlled a spheroid formation and decreased a cell viability in 3D cell culture. IF-induced cell proliferation inhibition was associated with a distinct increase of S and G2/M phase cell distribution in 2D cell cultre. In addition, IF significantly induced autophagy and generated reactive oxygen species(ROS). Interestingly, IF-induced cell cycle arrest and autophagy were recovered after pre-treatment of N-acetyl-L-cysteine, ROS scavenger. Conclusion : Our results indicate that IF induced ROS-mediated cell cycle arrest and autophagy and it may potentially useful for human fibrosarcoma treatment.

• YAKHAK HOEJI
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• v.43 no.3
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• pp.378-384
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• 1999

Retinoic acid (RA) and dibutyryl cyclic AMP (dbcAMP) induce the differentiation of the multipotent embryonic carcinoma cell line, F9 cells, into parietal endoderm like cell. The F9 cells are highly proliferative doubling approximately 12 hourse. S Phase is predominant, lasting 10 hours and G2/M phase occupies most of the remaining cycle (2 hours) and G1 phase is nearly non-existent. In this study, we showed the effect of RA and dbcAMPon the cell cycle associated molecules (especially around G1 phase) during F9 cell differentiation. Differentiation of F9 cells was induced by the combined addition of RA ($10^{-7}M$) and dbcAMP (0.5mM), and cells were harvested daily up to 4 days. Flow cytometric analysis showed the prolongation of G1 phase around 30 hours after induction. Western blot analysis revealed that the amount of cyclin D1 and cdk2 were increased at day 4. However, histone H1 kinase activity of cdk2 was decreased. These data strongly suggest that RA and dbcAMP induce the growth arrest of F9 cells at G1 phase by decreasing the activity of cdk2, although they have increased the protein contents of cyclin D1 and cdk2. The reason for the discrepancy between the H1 kinase activity and protein contents are not clear yet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.417-425
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• 2017

Cnidium monnieri (L.) Cusson is distributed in China and Korea, and the fruit of C. monnieri is used as traditional Chinese medicine to treat carbuncle and pain in female genitalia. In this study, we examined the anti-proliferation and cell cycle arrest effects of ethanol extracts from C. monnieri (CME) in AGS gastric cancer cells. Our results show that CME suppressed cell proliferation and induced release of lactate dehydrogenase (LDH) in AGS cells by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and LDH assay. Cell morphology was altered by CME in a dose-dependent manner. In order to identify the cell cycle arrest effects of CME, we investigated cell cycle analysis after CME treatment. In our results, CME induced cell cycle arrest at G1 phase. Protein kinase B (Akt) plays a major role in cell survival mechanisms such as growth, division, and metastasis. Akt protein regulates various downstream proteins such as glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$) and tumor protein p53 (p53). Expression levels of p-Akt, p-GSK-$3{\beta}$, p53, p21, cyclin E, and cyclin-dependent kinase 2 (CDK2) were determined by Western blot analysis. Protein levels of p-Akt, p-GSK-$3{\beta}$, and cyclin E were reduced while those of p53, p21, and p-CDK2 (T14/Y15) were elevated by CME. Moreover, treatment with CME, LY294002 (phosphoinositide 3-kinase/Akt inhibitor), BIO (GSK-$3{\beta}$ inhibitor), and Pifithrin-${\alpha}$ (p53 inhibitor) showed that cell cycle arrest effects were mediated through regulation of the Akt/GSK-$3{\beta}$/p53 signaling pathway. These results suggest that CME induces cell cycle arrest at G1 phase via the Akt/GSK-$3{\beta}$/p53 signaling pathway in AGS gastric cancer cells.

• KSBB Journal
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• v.23 no.5
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• pp.449-451
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• 2008

Ceramide has become a widely used ingredient in cosmetic and pharmaceutical industries, however, only a few yeast strains were investigated for the synthesis of ceramide and the concentration was very low. Ceramide is not only a core intermediate of sphingolipids but also an important modulator of many cellular events including apoptosis, cell cycle arrest, senescence, differentiation, and stress responses. In this study S.cerevisiae was grown in a batch culture and the cellular content of ceramide was measured at different growth phases. The ceramide content was highest at stationary phase and 2.01 mg ceramide/g cell was obtained.