[show abstract][hide abstract] ABSTRACT: The anticancer effect of Dangyuja (Citrus grandis Osbeck) leaf extract was investigated using SNU-16 human gastric cancer cells. Maximum cytotoxicity was observed from the chloroform fraction (CF) of the extract. Cell death was dose-dependent (IC50=ca. 92.15 μg/mL), and was characterized by apoptotic body formation and DNA fragmentation. Flowcytometric analysis showed that treatment of CF resulted in a marked accumulation of cells in the sub-G1 phase. The induction of apoptosis was confirmed by caspase-3 activity assays and immunoblotting using antibodies against Bid, Bcl-2, Bax, poly (ADP-ribose) polymerase, caspase-9, caspase-8, caspase-7, and caspase-3. Analyses of the CF by gas chromatography (GC) and GC-mass spectrometry tentatively identified 21 compounds, including linoleic acid, linolenic acid, palmitic acid, α-amyrin, γ-sitosterol, dihydrolanosterol, methyl palmitate, and nobiletin. These results provided the first evidence that the CF of a Dangyuja leaf extract induces apoptosis in SNU-16 cells. Our findings may lead to new strategies for the treatment of human gastric cancer.
Journal of the Korean Society for Applied Biological Chemistry 08/2013; 52(2). · 0.43 Impact Factor
[show abstract][hide abstract] ABSTRACT: Artemisia capillaris is a perennial herb that belongs to the family Campositae spp, and has been utilized in Korea for the treatment of abdominal pain, hepatitis, chronic liver disease, and coughing. The anti-inflammatory activity of the ethanol extract of A. capillaris (EtEAC) was investigated in this study. EtEAC did not affect the viability of various cells in a concentration range of 0-200 μg/mL. The DPPH radical scavenging ability of 10 μg/mL of EtEAC was comparable to that of 10 μg/mL of catechin. EtEAC exerted an anti-inflammatory effect on the mRNA expression levels of typical inflammatory cytokines (IL-6, IL1β) and cyclooxygenase-2 in LPS-stimulated RAW 264.7 cells. Additionally, EtEAC reduced nitric oxide (NO) production via the downregulation of inducible nitric oxide synthase transcription, rather than by scavenging NO. EtEAC exerted its anti-inflammatory effects by suppressing the activation of p38 and ERK at 200 μg/mL in LPS-stimulated RAW 264.7 cells.
Journal of the Korean Society for Applied Biological Chemistry 08/2013; 53(3). · 0.43 Impact Factor
[show abstract][hide abstract] ABSTRACT: Red variants of S. Japonicas show unique ecological characteristics and are indigenous to Jeju Island in South Korea. Various biological activities of red sea cucumber extracts (RSCEs) were evaluated. In comparison with positive controls, anti-oxidant activity of RSCEs was very low. In HL-60 and HT-29 cells, chloroform and ethyl acetate (EtOAc) fractions showed higher than 80 and 60% growth inhibition, respectively. Nuclear condensation and increased pro-apoptotic signaling revealed that RSCEs triggered apoptosis. EtOAc fractions also showed strong anti-inflammatory effects at sub-lethal concentrations in lipolysaccharide-stimulated RAW264.7 cells and suppressed more than 90% of nitric oxide (NO) and prostaglandin 2 productions at 50 μg/mL by inhibiting inducible NO synthase and cydooxygenase-2. Water-soluble fractions showed good antibacterial effects against Staphylococcus aureus and Staphylococcus epidermidis.
Journal of the Korean Society for Applied Biological Chemistry 08/2013; 54(5). · 0.43 Impact Factor
[show abstract][hide abstract] ABSTRACT: Nobiletin is a typical polymethoxyl flavone from citrus fruits that has anticancer properties, but the molecular mechanism of its inhibitory effects on the growth of p53-mutated SNU-16 human gastric cancer cells has not been explored. In this study, nobiletin was found to be effective at inhibiting the proliferation of SNU-16 cells than other flavonoids. Nobiletin induced the death of SNU-16 cells through apoptosis, as evidenced by the increased cell population in the sub-G1 phase, the appearance of fragmented nuclei, an increase in the Bax/Bcl-2 ratio, the proteolytic activation of caspase-9, an increase in caspase-3 activity, and the degradation of poly(ADP-ribose) polymerase (PARP) protein. We found that the combination of nobiletin plus the anticancer drug 5-fluorouracil (5-FU) reduced the viability of SNU-16 cells in a concentration-dependent manner and exhibited a synergistic anticancer effect (combination index = 0.38) when 5-FU was used at relatively low concentrations. The expression of p53 protein increased after treatment with 5-FU, but not nobiletin, whereas the expression of p21 (WAF1/CIP1) protein increased after treatment with nobiletin, but not 5-FU. The cellular responses to nobiletin and 5-FU occurred through different pathways. The results of this study suggest the potential application of nobiletin to the enhancement of 5-FU efficiency in p53 mutant tumors.
Nutrition and Cancer 02/2013; 65(2):286-95. · 2.70 Impact Factor
[show abstract][hide abstract] ABSTRACT: The aerial parts of Artemisia capillaris (Compositae) have been used in traditional Korean medicine as a cholagogic, antipyretic, anti-inflammatory, and diuretic purposes. In our previous study, ethanolic extracts of the plant demonstrated a marked anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells (J. Korean Soc. Appl. Biol. Chem., 2010, 53, 275-282). In the present study, capillarisin (CPS), a flavone, main constituent of A. capillaris, was examined for its anti-inflammatory activity in the cells. We found that CPS highly suppressed LPS-induced nitric oxide (NO) without exerting cytotoxic effects on RAW 264.7 cells. CPS inhibited the expression of LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and their mRNA in a dose-dependent manner. Also, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and prostaglandin E(2) (PGE(2)) secretion were decreased by CPS in LPS-stimulated macrophages. As a result, CPS inhibited proinflammatory cytokines, iNOS, and COX-2, which is attributed to the suppression of LPS-induced ERK, JNK, and nuclear factor-κB (NF-κB) activation. Therefore, we demonstrate here that CPS potentially inhibits the biomarkers related to inflammation through the abrogation of ERK, JNK, and NF-κB p65 activation, and it may be a potential therapeutic candidate for the treatment of inflammatory diseases.
Immunopharmacology and Immunotoxicology 11/2012; · 1.36 Impact Factor
[show abstract][hide abstract] ABSTRACT: Snail family proteins regulate transcription of molecules for cell-cell adhesion during epithelial-mesenchymal transition (EMT). Based on putative glycogen synthase kinase 3β (GSK-3β) phosphorylation sites within the Slug/Snail2, we explored the significance of GSK-3β-mediated phosphorylation in Slug/Snail2 expression during EMT. Mutation of the putative GSK-3β phosphorylation sites (S92/96A or S100/104A) enhanced the Slug/Snail2-mediated EMT properties of E-cadherin repression and vimentin induction, compared with wild-type Slug/Snail2. S92/96A mutation inhibited degradation of Slug/Snail2 and S100/104A mutation extended nuclear stabilization. Inhibition of GSK-3β activity caused similar effects, as did the phosphorylation mutations. Thus, our study suggests that GSK-3β-mediated phosphorylation of Slug/Snail2 controls its turnover and localization during EMT.
[show abstract][hide abstract] ABSTRACT: Pepsin-solubilised collagen (PSC) from Red Sea cucumber (Stichopus japonicus) was studied with respect to its wound-healing effects on a human keratinocyte (HaCaT) cell line. Disaggregated collagen fibres were treated with 0.1 M NaOH for 24 h and digested with pepsin for 72 h to reach maximum yield of 26.6%. The results of an in vitro wound-healing test showed that migration of HaCaT cells was 1.5-fold faster on PSC-coated plates than on untreated plates. The migration rate of sea cucumber PSC was similar to that of rat PSC, but five times higher than that of bovine gelatin. HaCaT cells grown on PSC-coated plates revealed increased fibronectin synthesis (6-fold and 3-fold compared to gelatin and rat PSC, respectively). Additionally, sea cucumber PSCs induced HaCaT cell proliferation by decreasing the G1 phase by 5% and maintaining a larger population (8%) of cells in mitosis. Collagen from Red Sea cucumber might be useful as an alternative to mammalian collagen in the nutraceutical and pharmaceutical industries.
[show abstract][hide abstract] ABSTRACT: Ginsenoside F2 (F2) was assessed for its antiproliferative activity against breast cancer stem cells (CSCs). F2 induced apoptosis in breast CSCs by activating the intrinsic apoptotic pathway and mitochondrial dysfunction. Concomitantly, F2 induced the formation of acidic vesicular organelles, recruitment of GFP-LC3-II to autophagosomes, and elevation of Atg-7 levels, suggesting that F2 initiates an autophagic progression in breast CSCs. Treatment with an inhibitor of autophagy enhanced F2-induced cell death. Our findings provide new insights into the anti-cancer activity of F2 and may contribute to the rational use and pharmacological study of F2.
Cancer letters 02/2012; 321(2):144-53. · 4.86 Impact Factor
[show abstract][hide abstract] ABSTRACT: A defensin-like peptide was previously detected in hemocytes of Manila clams (Ruditapes philippinarum). In the current study, we cloned and characterized this defensin, designated MCdef. Cloning produced a full-length gene sequence of 201 bp predicted to encode a 66-amino-acid precursor protein maturing to a 44-amino-acid residue. Amino acid sequence analysis showed that MCdef is similar to defensins from marine mollusks and ticks. Phylogenetic analysis suggested that MCdef is closely related to defensins from Mytilus galloprovincialis (Mediterranean mussel) and Crassostrea gigas (Pacific cupped oyster). The three-dimensional structure of MCdef was modeled using the solution structure of C. gigas defensin as a template. With the exception of three variable loop areas, the modeled structure of MCdef was identical to that of C. gigas defensin. MCdef antiserum was raised against a synthetic MCdef peptide and verified by Western blotting using recombinant MCdef. RT-PCR analysis demonstrated high levels of MCdef mRNA in hemocytes and adductor, foot, gill, mantle, palp, and siphon tissues of Vibrio tapetis-infected Manila clams, whereas in V. tapetis-uninfected Manila clams, the level of MCdef mRNA was low in adductor, palp, and siphon tissues and even lower in the other tested tissues. Immunohistochemical analysis revealed high MCdef expression was detected in the gill, the mantle, and the digestive tubules of the diverticulum of V. tapetis-infected Manila clams. Minimum inhibitory concentration (MIC) of the purified rMCdef was determined. MCdef showed highest activity against Streptococcus iniae and Staphylococcus aureus.
Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology 09/2011; 161(1):25-31. · 1.61 Impact Factor
[show abstract][hide abstract] ABSTRACT: The antiproliferative activities of the chloroform fraction (CF) of guava (Psidium cattleianum Sabine) leaf extract were evaluated using several cancer cell lines. Maximum cytotoxicity was observed in SNU-16, a human gastric carcinoma cell line, at concentrations of 50–100 μg/ml. Flow cytometric analysis demonstrated that CF treatment resulted in a marked accumulation of SNU-16 cells in the sub-G1 phase at concentrations of 100–200 μg/ml. The induction of apoptosis in SNU-16 cells was confirmed by immunoblotting using antibodies against Bcl-2, Bax, poly (ADP-ribose) polymerase (PARP), caspase-8, and caspase-3. The major CF phytochemicals were identified as ferulic acid, genistein, 3′, 4′, 5′ trimethoxy flavone, phlorizin, and oleanolic acid by high performance liquid chromatography coupled with a photo diode array and electrospray ionisation mass spectrometry (HPLC–PDA-ESI-MS). The results suggest that phytochemicals in the CF of guava (P. cattleianum) leaf extract induce apoptosis in SNU-16 cells. These findings may lead to new strategies for treating human gastric cancer.
[show abstract][hide abstract] ABSTRACT: Transmembrane 4 L six family member 5 (TM4SF5) is highly expressed in hepatocarcinoma and causes epithelial-mesenchymal transition (EMT) of hepatocytes. We found that TM4SF5-expressing cells showed lower mRNA levels but maintained normal protein levels in certain gene cases, indicating that TM4SF5 mediates stabilization of proteins. In this study, we explored whether regulation of proteasome activity and TM4SF5 expression led to EMT. We observed that TM4SF5 expression caused inhibition of proteasome activity and proteasome subunit expression, causing morphological changes and loss of cell-cell contacts. shRNA against TM4SF5 recovered proteasome expression, with leading to blockade of proteasome inactivation and EMT. Altogether, TM4SF5 expression appeared to cause loss of cell-cell adhesions via proteasome suppression and thereby proteasome inhibition, leading to repression of cell-cell adhesion molecules, such as E-cadherin.
Journal of Cellular Biochemistry 03/2011; 112(3):782-92. · 3.06 Impact Factor
[show abstract][hide abstract] ABSTRACT: Molecular and immunological probes were used to identify various life stages of Perkinsus olseni, a protozoan parasite of the Manila clam Ruditapes philippinarum, from a marine environment and decomposing clam tissue. Western blotting revealed that the antigenic determinants of the rabbit anti-P. olseni antibody developed in this study were peptides with molecular masses of 55.9, 24.0, and 19.2kDa. Immunofluorescent assay indicated that the rabbit anti-P. olseni IgG was specific to all life stages, including the prezoosporangium, trophozoite, and zoospore. Perkinsus olseni prezoosporangium-like cells were successfully isolated from marine sediment collected from Hwangdo on the west coast of Korea, where P. olseni-associated clam mortality has recurred for the past decade. Purified cells were positively stained with the rabbit anti-P. olseni antibody in an immunofluorescence assay, confirming for the first time the presence of P. olseni in marine sediment. Actively replicating zoospores inside the prezoosporangia were observed in the decomposing clam tissue collected from Hwangdo. P. olseni was also isolated from the feces and pseudofeces of infected clams and confirmed by PCR. The clams released 1-2 prezoosporangia per day through feces. The data suggested that the fecal discharge and decomposition of the infected clam tissue could be the two major P. olseni transmission routes.
Journal of Invertebrate Pathology 11/2010; 105(3):261-9. · 2.67 Impact Factor
[show abstract][hide abstract] ABSTRACT: Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome characterized by predisposition to early-onset cancers. HNPCC is caused by heterozygous loss-of-function mutations within the mismatch repair genes MLH1, MSH2, MSH6, PMS1, and PMS2. We genotyped the MLH1 and MSH2 genes in patients suffering from Lynch syndrome and in 11 unrelated patients who were diagnosed with colorectal cancer and had subsequently undergone surgery. Five Lynch syndrome patients carried germline mutations in MLH1 or MSH2. Two of these were identified as known mutations in MLH1: deletion of exon 10 and a point mutation (V384D). The remaining three patients exhibited novel mutations: a duplication (937_942dupGAAGTT) in MLH1; deletion of exons 8, 9, and 10; and a point mutation in MLH1 (F396I) combined with multiple missense mutations in MSH2 (D295G, K808E, Q855P, and I884T). The findings underline the importance of efficient pre-screening of conspicuous cases.
[show abstract][hide abstract] ABSTRACT: Overexpression of transmembrane 4 L six family member 5 (TM4SF5), a four-transmembrane L6 family member, causes aberrant cell proliferation and angiogenesis, but the roles of TM4SF5 in migration, invasion, and tumor metastasis remain unknown. Using in vitro hepatocarcinoma cells that ectopically or endogenously express TM4SF5 and in vivo mouse systems, roles of TM4SF5 in metastatic potentials were examined. We found that TM4SF5 expression facilitated migration, invadopodia formation, MMP activation, invasion, and eventually lung metastasis in nude mice, but suppression of TM4SF5 with its shRNA blocked the effects. Altogether, TM4SF5-mediated migration and invasion suggest that TM4SF5 may be therapeutically targeted to deal with TM4SF5-mediated hepatocellular cancers.
Journal of Cellular Biochemistry 09/2010; 111(1):59-66. · 3.06 Impact Factor
[show abstract][hide abstract] ABSTRACT: Galectin-1 (Gal-1) is important in immune function and muscle regeneration, but its expression and localization in adult tissues and primary leukocytes remain unclear. To address this, we generated a specific monoclonal antibody against Gal-1, termed alphahGal-1, and defined a sequential peptide epitope that it recognizes, which is preserved in human and porcine Gal-1, but not in murine Gal-1. Using alphahGal-1, we found that Gal-1 is expressed in a wide range of porcine tissues, including striated muscle, liver, lung, brain, kidney, spleen, and intestine. In most types of cells, Gal-1 exhibits diffuse cytosolic expression, but in cells within the splenic red pulp, Gal-1 showed both cytosolic and nuclear localization. Gal-1 was also expressed in arterial walls and exhibited prominent cytosolic and nuclear staining in cultured human endothelial cells. However, human peripheral leukocytes and promyelocytic HL60 cells lack detectable Gal-1 and also showed very low levels of Gal-1 mRNA. In striking contrast, Gal-1 exhibited an organized cytosolic staining pattern within striated muscle tissue of cardiac and skeletal muscle and colocalized with sarcomeric actin on I bands. These results provide insights into previously defined roles for Gal-1 in inflammation, immune regulation and muscle biology.
[show abstract][hide abstract] ABSTRACT: The antioxidant and antiproliferative properties of flesh and peel of mango (Mangifera indica L.) were investigated. The cytoprotective effect of mango flesh and peel extracts on oxidative damage induced by H2O2 in a human hepatoma cell line, HepG2, were determined, and the underlying mechanism was examined by a single-cell electrophoresis assay (comet assay). Treatment of HepG2 cell with mango peel extract prior to oxidative stress was found to inhibit DNA damage. The free radical scavenging activities of mango flesh and peel extracts were evaluated by electron spin resonance (ESR). The mango peel extract exhibited stronger free radical scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and alkyl radicals than mango flesh extract, regardless of ripeness. Similarly, peel extract exhibited significant antiproliferative effect against all tested cancer cell lines, compared to that of flesh extract, in a dose-dependent manner. The result also showed that the antiproliferative activity of mango flesh and peel extracts correlated with their phenolic and flavonoid contents. Thus, mango peel, a major by-product obtained during the processing of mango product, exhibited good antioxidant activity and may serve as a potential source of phenolics with anticancer activity.
[show abstract][hide abstract] ABSTRACT: The expression of matrix metalloproteinase-9 (MMP-9) has been reported in various cancers. Its expression is associated with tumorigenesis and tumor metastasis. Studies have shown that galectin-7, a beta-galactoside-binding animal lectin, is involved in various processes including the suppression of tumor growth. However, a recent study reported that the development of thymic lymphoma is accelerated by galectin-7 expression. In this report, we demonstrate that the expression of MMP-9 was increased by galectin-7 in human cervix epithelial cells (HeLa). When the galectin-7 gene was transfected to HeLa cells with the ECFP vector, the expression of MMP-9 mRNA increased, as compared to non-transfected cells. As a result, MMP-9 protein levels also increased, as indicated by Western blot and gelatin zymography. In addition, galectin-7-transfected cells exhibited increased invasion in the matrigel invasion system. Expression of MMP-9 is involved in several signaling pathways by various stimulation factors. Therefore, we investigated how the signaling pathway in galectin-7-transfected cells differs from that of non-transfected cells. Upon transfection of galectin-7, p38 MAPK was activated and SB203580, a chemical inhibitor of p38 MAPK, reversed the effects of galectin-7. These results indicate that galectin-7 increases the expression of MMP-9 through the p38 MAPK signaling pathway.
[show abstract][hide abstract] ABSTRACT: Chronic granulomatous disease (CGD) is a rare hereditary disorder characterized by recurrent life-threatening bacterial and fungal infections. The underlying defect in CGD is an inability of phagocytes to produce reactive oxygen species as a result of defects in NADPH oxidase. Considering that CGD generally affects about 3-4 in 1,000,000 individuals, it is surprising that the prevalence of CGD on Jeju Island is 20.7 in 1,000,000 individuals. We performed genetic analysis on 12 patients from 10 unrelated families and found that all patients had an identical homozygous single-base substitution of C to T in exon 1 (c.7C>T) of the CYBA gene, which was expected to result in a nonsense mutation (p.Q3X). Because Jeju Island has long been a geologically isolated region, the high prevalence of CGD on Jeju Island is presumably associated with an identical mutation inherited from a common ancestor or proband.
Journal of Korean medical science 12/2009; 24(6):1045-50. · 0.84 Impact Factor
[show abstract][hide abstract] ABSTRACT: Four-transmembrane L6 family member 5 (TM4SF5) and its homolog L6, a tumor antigen, form a four-transmembrane L6 family. TM4SF5 expression causes uncontrolled cell proliferation and angiogenesis. Although other genuine transmembrane 4 superfamily (TM4SF) members co-operate with integrins for cell migration, roles of TM4SF5 in the cellular spreading and migration are unknown. Using hepatocarcinoma cell clones that ectopically express TM4SF5, we found that cross talks via an extracellular interaction between TM4SF5 and integrin alpha2 in collagen type I environment inhibited integrin alpha2 functions such as spreading on and migration toward collagen I, which were recovered by suppression of TM4SF5 or structural disturbance of its second extracellular loop using a peptide or mutagenesis. Altogether, the observations suggest that TM4SF5 in hepatocytes negatively regulates integrin alpha2 function via an interaction between the extracellular loop 2 of TM4SF5 and integrin alpha2 during cell spreading on and migration through collagen I environment.