• Food Science and Biotechnology
• /
• v.18 no.3
• /
• pp.749-754
• /
• 2009

The polysaccharide (BB-pol) extracted from Bifidobacterium bifidum BGN4 showed growth inhibitory effects on several colon cancer cell lines such as HT-29 and HCT-116. To increase the yield of polysaccharide, B. bifidum BGN4 was cultured in various culture media with different compositions. When B. bifidum BGN4 was cultured in modified MRS broth containing phytic acid, the cells showed increased branch formation and enlarged morphology. The content of total carbohydrate and the ability of adhesion to intestinal epithelial cells were also increased by phytic acid. The polysaccharide obtained from the cells grown in the presence of phytic acid inhibited the proliferation of cancer cell lines such as HT-29 and MCF-7 cells but not normal colon cell line, FHC. Taken together, Bifidobacterium grown in the presence of phytic acid may confer enhanced beneficial function for the host.

• Molecules and Cells
• /
• v.40 no.5
• /
• pp.322-330
• /
• 2017

This study investigated the role of cancer/testis antigen DDX53 in regulating cancer stem cell-like properties. DDX53 shows co-expression with CD133, a marker for cancer stem cells. DDX53 directly regulates the SOX-2 expression in anti-cancer drug-resistant $Malme3M^R$ cells. DDX53 and miR-200b were found to be involved in the regulation of tumor spheroid forming potential of Malme3M and $Malme3M^R$ cells. Furthermore, the self-renewal activity and the tumorigenic potential of $Malme3M^R$-CD133 (+) cells were also regulated by DDX53. A miR-200b inhibitor induced the direct regulation of SOX-2 by DDX53 We therefore, conclude that DDX53 may serve as an immunotherapeutic target for regulating cancer stem-like properties of melanomas.

• BMB Reports
• /
• v.56 no.9
• /
• pp.508-513
• /
• 2023

The phytochemical quercetin has gained attention for its anti-inflammatory and anti-tumorigenic properties in various types of cancer. Tumorigenesis involves the aberrant regulation of kinase/phosphatase, highlighting the importance of maintaining homeostasis. Dual Specificity Phosphatase (DUSP) plays a crucial role in controlling the phosphorylation of ERK. The current study aimed to clone the DUSP5 promoter, and investigate its transcriptional activity in the presence of quercetin. The results revealed that quercetin-induced DUSP5 expression is associated with the serum response factor (SRF) binding site located in the DUSP5 promoter. The deletion of this site abolished the luciferase activity induced by quercetin, indicating its vital role in quercetin-induced DUSP5 expression. SRF protein is a transcription factor that potentially contributes to quercetin-induced DUSP5 expression at the transcriptional level. Additionally, quercetin enhanced SRF binding activity without changing its expression. These findings provide evidence of how quercetin affects anti-cancer activity in colorectal tumorigenesis by inducing SRF transcription factor activity, thereby increasing DUSP5 expression at the transcriptional level. This study highlights the importance of investigating the molecular mechanisms underlying the anti-cancer properties of quercetin, and suggests its potential use in cancer therapy.

• Molecules and Cells
• /
• v.38 no.6
• /
• pp.562-572
• /
• 2015

We previously reported the role of histone deacetylase 3 (HDAC3) in response to anti-cancer drugs. The decreased expression of HDAC3 in anti-cancer drug-resistant cancer cell line is responsible for the resistance to anti-cancer drugs. In this study, we investigated molecular mechanisms associated with regulation of HDAC3 expression. MG132, an inhibitor of proteasomal degradation, induced the expression of HDAC3 in various anti-cancer drug-resistant cancer cell lines. Ubiquitination of HDAC3 was observed in various anti-cancer drug-resistant cancer cell lines. HDAC3 showed an interaction with SIAH2, an ubiquitin E3 ligase, that has increased expression in various anti-cancer drug-resistant cancer cell lines. miRNA array analysis showed the decreased expression of miR-335 in these cells. Targetscan analysis predicted the binding of miR-335 to the 3'-UTR of SIAH2. miR-335-mediated increased sensitivity to anti-cancer drugs was associated with its effect on HDAC3 and SIAH2 expression. miR-335 exerted apoptotic effects and inhibited ubiquitination of HDAC3 in anti-cancer drug-resistant cancer cell lines. miR-335 negatively regulated the invasion, migration, and growth rate of cancer cells. The mouse xenograft model showed that miR-335 negatively regulated the tumorigenic potential of cancer cells. The down-regulation of SIAH2 conferred sensitivity to anti-cancer drugs. The results of the study indicated that the miR-335/SIAH2/HDAC3 axis regulates the response to anti-cancer drugs.

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

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.10
• /
• pp.4199-4202
• /
• 2015

Background: Hepatitis B virus infection is one of the major world health problems. Epigallocatechin-3 gallate is the major component of the polyphenolic fraction of green tea and it has an anti-viral, anti-mutagenic, anti-tumorigenic, anti-angiogenic, anti-proliferative, and/or pro-apoptotic effects on mammalian cells. In this study, our aim was to investigate the inhibition of HBV replication by epigallocatechin-3 gallate in the Hep3B2.1-7 hepatocellular carcinoma cell line. Materials and Methods: HBV-replicating Hep3B2.1-7 cells were used to investigate the preventive effects of epigallocatechin-3 gallate on HBV DNA replication. The expression levels of HBsAg and HBeAg were determined using ELISA. Quantitative real-time-PCR was applied for the determination of the expression level of HBV DNA. Results: Cytotoxicity of epigallocathechin-3-gallate was not observed in the hepatic carcinoma cell line when the dose was lower than $100{\mu}M$. The ELISA method demonstrated that epigallocatechin-3 gallate have strong effects on HBsAg and HBeAg levels. Also it was detected by real-time PCR that epigallocatechin-3 gallate could prevent HBV DNA replication. Conclusions: The obtained data pointed out that although the exact mechanism of HBV DNA replication and related diseases remains unclear, epigallocatechin-3 gallate has a potential as an effective anti-HBV agent with low toxicity.

• Molecules and Cells
• /
• v.39 no.4
• /
• pp.299-309
• /
• 2016

We have previously reported the role of miR-217 in anti-cancer drug-resistance. miRNA array and miRNA hybridization analysis predicted miR-30a-3p as a target of miR-217. miR-30a-3p and miR-217 formed a negative feedback loop and regulated the expression of each other. Ago1 immunoprecipitation and co-localization analysis revealed a possible interaction between miR-30a-3p and miR-217. miR-30a-3p conferred resistance to anti-cancer drugs and enhanced the invasion, migration, angiogenic, tumorigenic, and metastatic potential of cancer cells in CAGE-dependent manner. CAGE increased the expression of miR-30a-3p by binding to the promoter sequences of miR-30a-3p, suggesting a positive feedback loop between CAGE and miR-30a-3p. miR-30a-3p decreased the expression of p53, which showed the binding to the promoter sequences of miR-30a-3p and CAGE in anti-cancer drug-sensitive cancer cells. Luciferase activity assays showed that p53 serves as a target of miR-30a. Thus, the miR-30a-3p-CAGE-p53 feedback loop serves as a target for overcoming resistance to anti-cancer drugs.

• Journal of Life Science
• /
• v.22 no.11
• /
• pp.1571-1586
• /
• 2012

On earth, there are about 5,400 kinds of mammals, of which about 1,000 kinds are herbivores. Among herbivores, about 250 kinds are known to be ruminants. As for cattle and sheep, which are ruminants, fermentation takes places mainly in their rumen; in contrast, for pigs and men, which are non-ruminants, fermentation takes place mainly in their caecum, colon, and rectum. As for the kind and dominance of rumen microorganisms, Bacteroidetes account for 51% and Firmicutes for 43%. As for the dominance of the large intestine microorganisms in men, Firmicutes account for 65% and Bacteroidetes for 25%. Cell wall components are decomposed by microorganisms, and short chain fatty acids (SCFAs) are generated through fermentation; the ratio of acetate, propionate, and butyrate generate is 60:25:15. Butyrate absorbed through the primary butyrate transporter MCT1 (mono carboxylate transports-1) in the intestines activates such SCFA receptors as GPR43 and GPR41. Butyrate has a strong anti-tumorigenic function. Butyrate is characterized by the fact that it has an effect on many cancer cells, contributes to the coordination of functions in the cells, and induces cancer apoptosis. Butyrate activates caspase but inhibits the activity of HDAC (histone deacetylase), so as to induce apoptosis. In addition, it increases p53 expression, so as to induce cell cycle arrest and apoptosis. Anti-inflammation actions of SCFA include the reduction of IL-8 expression in intestinal epithelial cells, the inhibition of NO synthesis, and the restraint of the activity of NF-${\kappa}B$ (nuclear factor ${\kappa}B$), so as to suppress the occurrence of cancers caused by inflammation. Butyrate plays an important role in maintaining physiological functions of intestinal mucous membranes and is used as a cure for inflammatory bowel disease (IBD).

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.4
• /
• pp.1325-1331
• /
• 2012

Tumor formation and growth is dictated by a very small number of tumor cells, called cancer stem cells, which are capable of self-renewal. The genesis of cancer stem cells and their resistance to conventional chemotherapy and radiotherapy via mechanisms such as multidrug resistance, quiescence, enhanced DNA repair abilities and anti-apoptotic mechanisms, make it imperative to develop methods to identify and use these cells as diagnostic or therapeutic targets. Aldehyde dehydrogenase 1 (ALDH1) is used as a cancer stem cell marker. In this study, we evaluated ALDH1 expression in CaSki, HeLa and SiHa cervical cancer cells using the Aldefluor method to isolate ALDH1-positive cells. We showed that higher ALDH1 expression correlated with significantly higher rates of cell proliferation, microsphere formation and migration. We also could demonstrate that SiHa-ALDH1-positive cells were significantly more tumorigenic compared to SiHa-ALDH1-negative cells. Similarly, SiHa cells overexpressing ALDH1 were significantly more tumorigenic and showed higher rates of cell proliferation and migration compared to SiHa cells where ALDH1 expression was knocked down using a lentivirus vector. Our data suggested that ALDH1 is a marker of cervical cancer stem cells and expand our understanding of its functional role.

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