• 대한약침학회지
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• 제16권4호
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• pp.7-13
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• 2013

Objectives: Whether the ultra-highly-diluted remedies used in homeopathy can effectively bring about modulations of gene expressions through acetylation/deacetylation of histones has not been explored. Therefore, in this study, we pointedly checked if the homeopathically-diluted anti-cancer remedy Condurango 30C (ethanolic extract of Gonolobus condurango diluted $10^{-60}$ times) was capable of arresting the cell cycles in cervical cancer cells HeLa by triggering an epigenetic modification through modulation of the activity of the key enzyme histone deacetylase 2 vis-a-vis the succussed alcohol (placebo) control. Methods: We checked the activity of different signal proteins (like $p21^{WAF}$, p53, Akt, STAT3) related to deacetylation, cell growth and differentiation by western blotting and analyzed cell-cycle arrest, if any, by fluorescence activated cell sorting. After viability assays had been performed with Condurango 30C and with a placebo, the activities of histone de-acetylase (HDAC) enzymes 1 and 2 were measured colorimetrically. Results: While Condurango 30C induced cytotoxicity in HeLa cells in vitro and reduced HDAC2 activity quite strikingly, it apparently did not alter the HDAC1 enzyme; the placebo had no or negligible cytotoxicity against HeLa cells and could not alter either the HDAC 1 or 2 activity. Data on $p21^{WAF}$, p53, Akt, and STAT3 activities and a cell-cycle analysis revealed a reduction in DNA synthesis and G1-phase cell-cycle arrest when Condurango 30C was used at a 2% dose. Conclusion: Condurango 30C appeared to trigger key epigenetic events of gene modulation in effectively combating cancer cells, which the placebo was unable to do.

• The Korean Journal of Physiology and Pharmacology
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• 제16권5호
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• pp.349-353
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• 2012

Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.

• Biomolecules & Therapeutics
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• 제16권1호
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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.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8135-8140
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• 2016

Background: Cell cycle regulatory proteins are suitable targets for cancer therapeutic development since genetic alterations in many cancers also affect the functions of these molecules. Strobilanthes crispus (S. crispus) is traditionally known for its potential benefits in treating various ailments. We recently reported that an active sub-fraction of S. crispus leaves (SCS) caused caspase-dependent apoptosis of human breast cancer MCF-7 and MDA-MB-231 cells. Materials and Methods: Considering the ability of SCS to also promote the activity of the antiestrogen, tamoxifen, we further examined the effect of SCS in modulating cell cycle progression and related proteins in MCF-7 and MDA-MB-231 cells alone and in combination with tamoxifen. Expression of cell cycle-related transcripts was analysed based on a previous microarray dataset. Results: SCS significantly caused G1 arrest of both types of cells, similar to tamoxifen and this was associated with modulation of cyclin D1, p21 and p53. In combination with tamoxifen, the anticancer effects involved downregulation of $ER{\alpha}$ protein in MCF-7 cells but appeared independent of an ER-mediated mechanism in MDA-MB-231 cells. Microarray data analysis confirmed the clinical relevance of the proteins studied. Conclusions: The current data suggest that SCS growth inhibitory effects are similar to that of the antiestrogen, tamoxifen, further supporting the previously demonstrated cytotoxic and apoptotic actions of both agents.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2005년도 제45회 학술심포지움 및 추계학술대회
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• pp.35-35
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• 2005

• International Journal of Oral Biology
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• 제36권1호
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• pp.13-21
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• 2011

Chios gum mastic (CGM) is produced from Pistiacia lentiscus L var chia, which grows only on Chios Island in Greece. CGM is a kind of resin extracted from the stem and leaves, has been used for many centuries in many Mediterranean countries as a dietary supplement and folk medicine for stomach and duodenal ulcers. CGM is known to induce cell cycle arrest and apoptosis in some cancer cells. This study was undertaken to investigate the alteration of the cell cycle and induction of apoptosis following CGM treatment of HL-60 cells. The viability of the HL-60 cells was assessed using the MTT assay. Hoechst staining and DNA electrophoresis were employed to detect HL-60 cells undergoing apoptosis. Western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity analyses were also employed. CGM treatment of HL-60 cells was found to result in a dose- and time-dependent decrease in cell viability and apoptotic cell death. Tested HL-60 cells showed a variety of apoptotic manifestations and induced the downregulation of G1 cell cycle-related proteins. Taken collectively, our present findings demonstrate that CGM strongly induces G1 cell cycle arrest via the modulation of cell cycle-related proteins, and also apoptosis via proteasome, mitochondrial and caspase cascades in HL-60 cells. Hence, we provide evidence that a natural product, CGM could be considered as a novel therapeutic for human leukemia.

• BMB Reports
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• 제51권11호
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• pp.545-546
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• 2018

With emerging evidence on the importance of non-cell autonomous toxicity in neurodegenerative diseases, therapeutic strategies targeting modulation of key immune cells. including microglia and Treg cells, have been designed for treatment of ALS and other neurodegenerative diseases. Strategy switching the patient's environment from a pro-inflammatory toxic to an anti-inflammatory, and neuroprotective condition, could be potential therapy for neurodegenerative diseases. Mesenchymal stem cells (MSCs) regulate innate and adaptive immune cells, through release of soluble factors such as $TGF-{\beta}$ and elevation of regulatory T cells (Tregs) and T helper-2 cells (Th2 cells), would play important roles, in the neuroprotective effect on motor neuronal cell death mechanisms in ALS. Single cycle of repeated intrathecal injections of BM-MSCs demonstrated a clinical benefit lasting at least 6 months, with safety, in ALS patients. Cytokine profiles of CSF provided evidence that BM-MSCs, have a role in switching from pro-inflammatory to anti-inflammatory conditions. Inverse correlation of $TGF-{\beta}1$ and MCP-1 levels, could be a potential biomarker to responsiveness. Thus, additional cycles of BM-MSC treatment are required, to confirm long-term efficacy and safety.

• International Journal of Oral Biology
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• 제39권1호
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• pp.23-33
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• 2014

Several studies have shown that curcumin, which is derived from the rhizomes of turmeric, possesses antimicrobial, antioxidant and anti-inflammatory properties. The antitumor properties of curcumin have also now been demonstrated more recently in different cancers. This study was undertaken to investigate the modulation of cell cycle-related proteins and the mechanisms underlying apoptosis induction by curcumin in the SCC25 human tongue squamous cell carcinoma cell line. Curcumin treatment of the SCC25 cells resulted in a time- and dose-dependent reduction in cell viability and cell growth, and onset of apoptotic cell death. The curcumin-treated SCC25 cells showed several types of apoptotic manifestations, such as nuclear condensation, DNA fragmentation, reduced MMP and proteasome activity, and a decreased DNA content. In addition, the treated SCC25 cells showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40/CAD into the nuclei, a significant shift in the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-7, caspase-6, caspase-3, PARP, lamin A/C, and DFF45/ICAD. Furthermore, curcumin exposure resulted in a downregulation of G1 cell cycle-related proteins and upregulation of $p27^{KIP1}$. Taken together, our findings demonstrate that curcumin strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via proteasomal, mitochondrial, and caspase cascades in SCC25 cells.

• Biomolecules & Therapeutics
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• 제17권3호
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• pp.282-287
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• 2009

Ochnaflavone is a natural biflavonoid and mainly found in the caulis of Lonicera japonica (Caprifoliaceae). Biological activities such as anti-inflammatory and anti-atherogenic effects have been previously reported. The anticancer activity of ochnaflavone, however, has been poorly elucidated yet. In the present study, we investigated the effect of ochnaflavone on the growth inhibitory activity in cultured human colon cancer cell line HCT-15. Ochnaflavone inhibited the proliferation of the cancer cells with an $IC_{50}$ value of $4.1{\mu}M$. Flow cytometric analysis showed that ochnaflavone arrested cell cycle progression in the G2/M phase, and induced the increase of sub-G1 peak in a concentration-dependent manner. Induction of cell cycle arrest was correlated with the modulation of the expression of cell cycle regulating proteins including cdc2 (Tyr15), cyclin A, cyclin B1 and cyclin E. The increase of sub-G1 peak by the higher concentrations of ochnaflavone (over $20{\mu}M$) was closely related to the induction of apoptosis, which was evidenced by the induction of DNA fragmentation, activation of caspase-3, -8 and -9, and cleavage of poly-(ADP-ribose) polymerase. These findings suggest that the cell cycle arrest and induction of apoptosis might be one possible mechanism of actions for the anti-proliferative activity of ochnaflavone in human colon cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1403-1410
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• 2014

Epigenetic regulators like histone deacetylases (1 and 2), and viral onco-proteins (E6/E7) are known to be overexpressed in cervical cancer cells. The present study was designed to investigate the effect of curcumin on HDACs (1 and 2) and HPV E6/E7 in the cervical cancer cell line SiHa and a drug resistant clone $SiHa^R$ (derived from SiHa). It was further intended to investigate whether curcumin could sensitize the cells towards cisplatin induced cell killing by modulation of multi drug resistant proteins like MRP1 and Pgp1. Curcumin inhibited HDACs, HPV expression and differentially increased acetylation and up-regulation of p53 in SiHa and $SiHa^R$, leading to cell cycle arrest at G1-S phase. Up-regulation of pRb, p21, p27 and corresponding inhibition of cyclin D1 and CDK4 were observed. Cisplatin resistance in $SiHa^R$ due to over-expression of MRP1 and Pgp1 was overcome by curcumin. Curcumin also sensitized both the cervical cancer cells towards cisplatin induced cell killing. Inhibition of HDACs and HPVs led to cell cycle arrest at G1/S phase by alteration of cell cycle regulatory proteins. Suppression of MRP1 and Pgp1 by curcumin resulted in sensitization of cervical cancer cells, lowering the chemotherapeutic dose of the drug cisplatin.