• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4357-4361
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• 2015

Thunbergia Laurifolia Linn. (TL) is one of the most familiar plants in Thai traditional medicine that is used to treat various conditions, including cancer. However, the antitumor activity of TL or its constituents has never been reported at the molecular level to support the folklore claim. The present study was designed to investigate the antitumor effect of an aqueous extract of TL in human breast cancer cells and the possible mechanism(s) of action. An aqueous crude extract was prepared from dried leaves of TL. Folin-Ciocalteu colorimetric assays were used to determine the total phenolic content. Antiproliferative and cell cycle effects were evaluated in human breast adenocarcinoma MCF-7 cells by MTT reduction assay, cell growth inhibition, clonogenic cell survival, and flow cytometric analysis. Free radical generation by the extracts was detected using electron paramagnetic resonance spectroscopy. The exposure of human breast adenocarcinoma MCF-7 cells to a TL aqueous extract resulted in decreases in cell growth, clonogenic cell survival, and cell viability in a concentration-dependent manner with an $IC_{50}$ value of $843{\mu}g/ml$. Treatments with extract for 24h at $250{\mu}g/ml$ or higher induced cell cycle arrest as indicated by a significant increase of cell population in the G1 phase and a significant decrease in the S phase of the cell cycle. The capability of the aqueous extract to generate radical intermediates was observed at both high pH and near-neutral pH conditions. The findings suggest the antitumor bioactivities of TL against selected breast cancer cells may be due to induction of a G1 cell cycle arrest. Cytotoxicity and cell cycle perturbation that are associated with a high concentration of the extract could be in part explained by the total phenolic contents in the extract and the capacity to generate radical intermediates to modulate cellular proliferative signals.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2207-2212
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• 2012

Overexpression of DNA methyltransferase 1 (DNMT1) has been detected in many cancers. Tobacco exposure is known to induce genetic and epigenetic changes in the pathogenesis of malignancy. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is an important carcinogen present in tobacco smoke; however the detailed molecular mechanism of how NNK induces esophageal carcinogenesis is still unclear. We found that DNMT1 was overexpressed in ESCC tissues compared with paired non-cancerous tissues, the overexpression being correlated with smoking status and low expression of $RAR{\beta}$. The latter could be upregulated by NNK treatment in Het-1A cells, and the increased DNMT1 expression level reflected promoter hypermethylation and downregulation of retinoic acid receptor ${\beta}$($RAR{\beta}$). RNA interference mediated knockdown of DNMT1 resulted in promoter demethylation and upregulation of $RAR{\beta}$ in KYSE30 and TE-1 cells. 3-(4,5-Dimethyl-thiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometric analysis demonstrated that NNK treatment in Het-1A cells could enhance cell proliferation and inhibit cell apoptosis in a dose-dependent manner. In conclusion, DNMT1 overexpression is correlated with smoking status and low expression of $RAR{\beta}$ in esophageal SCC patients. NNK could induce $RAR{\beta}$ promoter hypermethylation through upregulation of DNMT1 in esophageal squamous epithelial cells, finally leading to enhancement of cell proliferation and inhibition of apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2409-2414
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• 2012

Objective: Traditional Chinese herbal medicines have a very long history. Rosa roxburghii Tratt and Fagopyrum cymosum are two examples of plants which are reputed to have benefits in improving immune responses, enhancing digestive ability and demonstrating anti-aging effects. Some evidence indicates that herbal medicine soups containing extracts from the two in combination have efficacy in treating malignant tumors. However, the underlying mechanisms are far from well understood. The present study was therefore undertaken to evaluate anticancer effects and explore molecular mechanisms in vitro. Methods: Proliferation and apoptosis were assessed with three carcinoma cell lines (human esophageal squamous carcinoma CaEs-17, human gastric carcinoma SGC-7901 and pulmonary carcinoma A549) by MTT assay and flow cytometry, respectively, after exposure to extract from Rosa roxburghii Tratt (CL) and extract from Fagopyrum cymosum (FR). $IC_{30}$ of CL and FR were obtained by MTT assay. Tumor cells were divided into four groups : control with no exposure to CL or FR; CL with $IC_{30}$ CL; FR with $IC_{30}$ FR; CL+FR group with 1/2 ($IC_{30}$ CL + $IC_{30}$ FR). RT-PCR and Western blot analysis were used to detect the expression of Ki-67, Bax and Bcl-2 at mRNA and protein levels. Results: Compared with the CL or FR groups, the combination of CL+FR showed significant inhibition of cell growth and increase in apoptosis; the mRNA and protein expression levels of Ki-67 and Bcl-2 in CL+FR group were all greatly decreased, while the expression of Bax was markedly increased. Conclusions: These results indicate that the synergistic antitumor effects of combination of CL and FR are related to inhibition of proliferation and induction of apoptosis.

• Herbal Formula Science
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• v.28 no.1
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• pp.15-27
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• 2020

Objectives : We selected three herb-combined remedies, Bigihwan (BGH), Daechilgitang (DCGT) and Mokwhyangbinranghwan (MHBRH), through Donguibogam text-mining analysis, and evaluated their anti-cancer effects on human hepatocellular carcinoma Hep3B cells. Methods : Cytotoxicity was assessed by an MTT assay. Apoptosis rate, autophagy and ROS level were detected by flow cytometry. The autophagy was also observed by Cyto-ID staining fluorescence microscopy. The expression of autophagy, mitophagy and pexophagy regulatory proteins was detected by Western blot analysis. Results : BGH showed the strongest effect among the three prescriptions in inhibiting Hep3B cell viability, which was associated with the induction of apoptosis and autophagy. Autophagy blockers improved cell viability and reduced apoptosis after BGH and DCGT treatments, indicating that autophagy by these prescriptions enhanced Hep3B cells against their cytotoxicity. However, MHBRH enhanced the reduction of cell viability and apoptosis by autophagy blockers. Induction of autophagy by BGH treatment was associated with mitophagy due to mitochondrial dysfunction than DCGT and MHBRH-treated cells. In addition, induction of apoptosis by BGH treatment was ROS-dependent and showed the possibility of pexophagy involvement. Conclusion : Although further studies need to be conducted to study the efficacy and mechanism of accurate anticancer activity, the present results will serve as important sources of understanding the mechanism of action of herbal remedies prescribed for liver disease as documented in Donguibogam.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.77-87
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• 1997

PFO(pyrolized fuel oil) and $C_{10}^{+}$ oil, which are the residual heavy oils form a NCC(naphtha cracking center), were heat-treated to produce the precursor-pitch for carbon materials. After PFO was initially distilled near $300^{\circ}C$ to separate the volatile matters recovering as high-quality fuel oil, the residuum of nonvolatile precursor-pitch was then thermally pyrolized in the temperature ranges from $350^{\circ}C$ to $450^{\circ}C$. Spinnable isotropic pitch with the softening point of $200^{\circ}C$ and the toluene insolubles of 36wt% was obtained at $365^{\circ}C$, and then was successfully spun through a spinneret(0.5mm diameter). After spinning, an isotropic carbon fiber of $25{\mu}m$ diameter was obtained via oxidation and craboniation procedures. Mesophase spherules began to be observed from the product pitch pyrolized at $400^{\circ}C$, and bulk mesophase with a flow texture was observed above $420^{\circ}C$. In the case of $C_{10}^{+}$ was the feed was polymerized in the presence $H_2SO_4$ at room temperature to increase the molecular weight and then heat-treated gradually up to $200{\sim}250^{\circ}C$. The products obtained with the softening point of $80{\sim}190^{\circ}C$ were carbonized at 500 and $1000^{\circ}C$ to examine the morphology.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.915-921
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• 2013

Background: Hepatocellular carcinoma is one of the leading causes of mortalities worldwide. The search for new therapeutic targets is of utmost importance for improved treatment. Altered expression of HDAC1 in hepatocellular carcinoma (HCC) and its requirement for liver formation in zebrafish, suggest that it may regulate key events in liver carcinogenesis and organogenesis. However, molecular mechanisms of HDAC1 action in liver carcinogenesis are largely unknown. The present study was conducted to identify HDAC1 interacting proteins in HepG2 cells using modified SH-double-affinity purification coupled with liquid mass spectrophotemetery. Materials and Methods: HepG2 cells were transfected with a construct containing HDAC1 with a C-terminal strepIII-HA tag as bait. Bait proteins were confirmed to be expressed in HepG2 cells by western blotting and purified by double affinity columns and protein complexes for analysis on a Thermo LTQ Orbitrap XL using a C18 nano flow ESI liquid chromatography system. Results: There were 27 proteins which showed novel interactions with HDAC1 identified only in this study, while 14 were among the established interactors. Various subunits of T complex proteins (TCP1) and prefoldin proteins (PFDN) were identified as interacting partners that showed high affinity with HDAC1 in HepG2 cells. Conclusions: The double affinity purification method adopted in this study was very successful in terms of specificity and reproducibility. The novel HDAC1 complex identified in this study could be better therapeutic target for treatment of hepatocellular carcinoma.

• IMMUNE NETWORK
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• v.6 no.1
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• pp.20-26
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• 2006

Background: Rheumatoid arthritis (RA) is a chronic and systemic inflammatory disease that is characterized by invasive synovial hyperplasia, leading to progressive joint destruction. Recent studies have described that RA is caused by virus, bacteria or outside material. Approximately 2 to 20% of RA cases arc reported to be associated with infected hepatitis C virus (HCV). However, the mechanisms underlying virus-induced RA are still unknown. Moreover, few molecular studies have addressed the inflammatory aspects of HCV-associated autoimmune RA. In this study, we aimed to determine whe ther or not another HCV core protein transactivates the IL-8 gene expression, prototypic chemokine, in synovial cell. Methods: To establish the HCV core expressing stable synovial cell line, pCI-neo-core, a plasmid encoding HCV core protein, were transfected to HIG-82 cell line that is an established cell line from rabbit periaricular soft tissue. We examined the morphological changes and cell cycle distribution of HIG-82 cells with expression of HCV core protein by inverted microscopy and flow cytometry analysis, respectively. Also, we determined the mRNA levels of Interleukin (IL)-6 and IL-8 related to the inflammation by RT-PCR and then analyzed regulation of IL-8 expression by the NF-${\kappa}B$ pathway. Results: Our study showed no significant differences in morphology and cell cycle between HIG-82 control cell line and HIG-82 expressing HCV core protein. However, expression of HCV core protein induces the IL-8 mRNA expression in HIG-82 core cells via activated NF-${\kappa}B$ pathway. Conclusion: These results suggest that HCV core protein can lead to enhanced IL-8 expression. Such a proinflammatory role may contribute to the etiologic pathogenesis in RA patients with HCV infection.

• BMB Reports
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• v.31 no.2
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• pp.111-116
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• 1998

HLA-DR4 is the dominant allele of MHC class II genes in Koreans. In particular, the $DRB1^*0405$ subtype has been reported to be almost exclusively expressed in Far East Asians, and has also been observed to be strongly associated with rheumatoid arthritis in Koreans and the Japanese. Identification of this specific allele has been mainly performed by PCR-based methods, which is often time consuming, costly, and involves tedious procedures such as the isolation of genomic DNA, PCR, and gel electrophoresis. To develop a more convenient tool for screening vast amounts of samples as well as to generate reagents which might also be used in other applications, in this study, antibodies were produced against this specific HLA subtype. By PCR, an allelespecific region covering the ${\beta}1$ domain of $DRB1^*0405$ was amplified and recombinantly expressed in E.coli. Immunization of Lewis rats with the purified protein yielded an allele specific antiserum. Western blot analysis showed the selective detection of the HLA-DR ${\beta}-chain$. Using this antiserum, established cell lines and peripheral blood lymphocytes were analyzed on their HLA haplotype by fluorescence activated flow cytometry. These novel antibodies will provide a powerful tool in the detection and investigation of DR4 alleles.

• BMB Reports
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• v.39 no.6
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• pp.722-729
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• 2006

Recently, we have reported that 3-hydrogenkwadaphnin (3-HK), a diterpene ester isolated from Dendrostellera lessertii (Thymealeaceae), is very effective against leukemia cell lines without any detectable effects on normal cells (Moosavi et al., 2005b). In this study, we report that 3-HK induces $G_1$ cell-cycle arrest, differentiation and apoptosis in APL NB4 cell line. Indeed, the drug between 24 to 96 h induced 7-65% growth inhibition of NB4 cells. Cell viability was also decreased by 2-55% between 24 to 96 h treatments with the drug, respectively. These effects of the drug were also dose-dependent. According to flow cytomtry results, 3-HK (15 nM) induced a significant G1-arrest up to 24 h which was consequently followed with appearance of sub-$G_1$ peak at 72 to 96 h. Hoechst 33258 staining and DNA fragmentation assays confirmed the occurrence of apoptosis among the treated cells. On the other hand, NBT reducing assay, Wright-Giemsa staining, phagocytic activity and expression of cell surface markers (CD11b and CD14) confirmed that the inhibition of proliferation is associated with differentiation especially toward macrophage-like morphology. Interestingly, 3-HK at 5 and 10 nM enhanced the effects of all-trans retinoic acid (ATRA) in NB4 cells. Based on these results, 3-HK might become an ideal candidate for treatment of APL patients pending full exploration of its biological functions.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.8
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• pp.849-855
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• 2012

The effect of electric fields on the response of diffusion flames in a counterflow has been investigated experimentally by varying the AC voltage and frequency. The result showed that the flame was stationary with high AC frequency above the threshold frequency, and it increased with the applied voltage and then leveled off at 35 Hz. Below the threshold frequency, however, the flame oscillated with a frequency that was synchronized with the applied AC frequency. This oscillation can be attributed to the ionic wind effect due to the generation of bulk flow, which arises from the momentum transfer by molecular collisions between neutral molecules and ions, where the ions in the reaction zone were accelerated by the Lorentz force.