Stomach Cancer Cell Lines Research Articles

Ieodoglucomides A and B from a Marine-Derived Bacterium Bacillus licheniformis

Ieodoglucomides A (1) and B (2), unique glycolipopeptides consisting of an amino acid, a new fatty acid, a succinic acid, and a sugar, were isolated from a Marine-derived bacterium Bacillus licheniformis. The absolute stereochemistry of 1 and 2 was determined by deploying coupling constants, Marfey's and Mosher's methods, and literature reviews. Compounds 1 and 2 displayed moderate in vitro antimicrobial activity. Furthermore, ieodoglucomide B (2) exhibited cytotoxic activity against lung cancer and stomach cancer cell lines with GI(50) values of 25.18 and 17.78 μg/mL, respectively.

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

발아 기간에 따른 벼(Oryza sativa L.)의 항산화활성과 in vitro 항암활성

This study was conducted on the antioxidant activity and in vitro anticancer effects of rough rice (Oryza sativa L.) by germination periods. Rough rice was germinated at 37℃ for 8 days and then extracted with 70% ethanol. It was then analyzed for total polyphenol content, reducing power, antioxidant activities, and in vitro anticancer effects. Total polyphenol content increased from 3.12 mg/g for raw rough rice to 4.05 mg/g at 4 days of germination. Also reducing power increased from 0.96 to 1.25 (p<0.05). DPPH radical scavenging activity increased from 29.25% at 0 day to 34.82% at 2 days. ABTS radical scavenging activity increased from 3.05 mg AA eq/100 g at 0 day to 3.84 mg AA eq/100 g at 4 days, and then decreased afterward. The anticancer effect of ethanol extract at 4 days on stomach cancer cell line (AGS) and colon cancer cell line (HCT-116) showed higher values compared with raw rough rice extract. These results suggest that the best germination periods for increasing biological activities may be 3～4 days.

15-PGDH is reduced and induces apoptosis and cell cycle arrest in gastric carcinoma

To investigate the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in human gastric cancer and it's mechanism in apoptosis and cell cycle arrest. Expression of 15-PGDH mRNA and protein was examined by immunohistochemistry, immunocytochemistry, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting in tissue from human gastric cancer, gastric precancerous state (gastric polyps and atrophic gastritis), normal stomach, and gastric cancer cell lines. The relationship between gastric cancer, gastric precancerous state and 15-PGDH expression was determined. The association between expression of 15-PGDH and various clinicopathological parameters in gastric cancer was evaluated. Human gastric cancer cell line SGC-7901 was transfected with 15-PGDH expression plasmids. The effect of 15-PGDH on the cell cycle was examined by flow cytometry. The effect of 15-PGDH on apoptosis was examined by transmission electron microscopy, flow cytometry and transferase mediated nick end labeling (TUNEL) assay. Expression of cell cycle (p21, p27, p16 and p53) and apoptosis (Survivin, BCL-2, BCL-X(L), BAK and BAX) genes was analyzed by RT-PCR. Expression of 15-PGDH mRNA and protein in human gastric cancer tissues was significantly lower than in normal gastric tissues (P < 0.01). Expression in human gastric cancer cell lines MKN-28 and MKN-45 was reduced, and absent in SGC-7901 cells (P < 0.05). Reduction of 15-PGDH expression was also found in precancerous tissues, such as gastric polyps and atrophic gastritis (P < 0.01). There was a significant difference in expression of 15-PGDH among various gastric cancer pathological types (P < 0.05), with or without distant metastasis (P < 0.05) and different TNM stage (P < 0.01). Flow cytometry demonstrated a significant increase in apoptotic cells in SGC-7901 cells transfected with pcDNA3/15-PGDH plasmid for 24 h and 48 h (P < 0.01), and an increased fraction of sub-G1 phase after transfection (P < 0.05). TUNEL assay showed an increased apoptotic index in cells overexpressing 15-PGDH (P < 0.01). After transfection, expression of proapoptotic genes, such as BAK (P < 0.05), BAX and p53 (P < 0.01), was increased. Expression of antiapoptotic genes was decreased, such as Survivin, BCL-2 and BCL-X(L) (P < 0.01). Expression of cyclin-dependent kinase inhibitors p21 and p16 (P < 0.01) was significantly upregulated in cells overexpressing 15-PGDH. Reduction of 15-PGDH is associated with carcinogenesis and development of gastric carcinoma. 15-PGDH induces apoptosis and cell cycle arrest in SGC-7901 cells.

Abstract C235: Interleukin-6 secreted by cancer-associated fibroblasts mediates gemcitabine resistance in pancreatic cancer.

Abstract Introduction: Pancreatic ductal adenocarcinoma is characterized by a dense stroma containing an abundance of cancer-associated fibroblasts (CAFs). It is also notably resistant to gemcitabine. We hypothesize that the large population of CAFs in pancreatic tumors secrete elevated levels of multiple soluble factors, which promote survival of pancreatic cancer cells and reduce their sensitivity to gemcitabine. Previously, we found that growth of MiaPaCa-2 and BxPC-3 tumors was suppressed with gemcitabine treatment, but that of tumors from MiaPaCa-2 and BxPC-3 co-injected with primary pancreatic CAFs was not. This suggests that the presence of CAFs causes pancreatic cancer cells to become more resistant to gemcitabine. Subsequent Affymetrix analyses showed that interleukin-6 (IL-6) is one of 382 genes that are differentially upregulated by &amp;gt;2-fold (P&amp;lt;0.05) in primary pancreatic CAFs as compared to normal fibroblasts. The objectives of the current study are to validate the expression/secretion of IL-6 as well as other components of the IL-6 signaling pathway, and to determine how IL-6 affects the sensitivity of pancreatic cancer cells to gemcitabine. Methods: Sixteen primary CAF lines were established in culture from resected pancreatic ductal adenocarcinoma tumor tissues. As well, eleven primary orthotopic tumor xenograft lines were established in SCID mice from the resected tissues. Subcutaneous tumors were also grown by injecting 5×106 MiaPaCa-2, BxPC-3, or Panc-1 pancreatic cancer cells into SCID mice. Using ELISA, the levels of IL-6, soluble IL-6 receptor (sIL-6R) and the soluble form of gp130 were evaluated in the primary CAFs and orthotopic tumor xenografts, as well as in several pancreatic cancer cell lines. Levels of mouse IL-6 in the serum of mice bearing orthotopic tumors and subcutaneous cell line xenografts were also assayed. Results: The levels of human IL-6 protein were 1.1- to 79-fold higher in the CAF lines than in normal human fibroblasts. However, human IL-6 protein was not detected in pancreatic cancer cell lines PK8, MiaPaCa-2, Panc-1, Capan-2, BxPC-3, or in normal human pancreatic ductal epithelial cells (HPDEs). The levels of mouse IL-6 protein were 1.2- to 94-fold higher in the serum of mice bearing orthotopic tumors as compared to the serum of normal healthy mice. Interestingly, no mouse IL-6 protein was detected in the serum of mice bearing subcutaneous cancer cell line tumors. Furthermore, high levels of mouse IL-6 (12–100 pg/mg) but not human IL-6 were evident in the lysates of the orthotopic tumors. Human sIL-6Rprotein levels were found to be high (24–65 pg/mg) in pancreatic cancer cell lines, but present only at low levels (∼12 pg/mg) in four of the sixteen CAF lines. It was also detected at 13–66 pg/mg in all of the orthotopic tumors. Soluble gp130 protein was observed at higher levels in the CAFs than in the pancreatic cancer cell lines. It was also detected in all of the orthotopic tumors. Conclusion: Our results demonstrate that CAFs are the major producers of IL-6 in pancreatic tumors. It is likely that IL-6 secreted by CAFs binds to IL-6 receptors on pancreatic cancer cells, resulting in the activation of downstream cell survival proteins. Co-culture experiments are underway to identify these proteins and to determine if inhibition of IL-6 signaling may increase the sensitivity of pancreatic cancer cells to gemcitabine. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C235.

Screening of in vitro cytotoxic activity of some medicinal plants used traditionally to treat cancer in Chhattisgarh state, India

Objective To explore the cytotoxic activity of the alcoholic extracts of some medicinal plants used traditionally to treat cancer in Chhattisgarh state, India. Methods In-vitro cytotoxicity of alcoholic extracts of five plants i.e. Artocarpus heterophyllus, Alangium salvifolium, Buchanania lanzan, Sesbania grandiflora and Wrightia tinctoria was studied against human breast cancer (MCF-7) and human leukemia (HL-60) tumor cell lines, using the thiazolyl blue test (MTT) assay. Results Alcoholic extract of Sesbania grandiflora exhibited a prominent inhibitory effect against MCF-7 (IC 50 7.00±0.08 μg/mL) and HL-60 (IC 50 18.50±0.60 μg/mL) under in vitro condition. Conclusions From the result it can be found that the Sesbania grandiflora extract has potent in vitro cytotoxic activity.

오가피 부위별 열수 추출액의 기능적 특성

Acanthopanax sessiliflorus (A. sessiliflorus) has been known as a traditional medicine having anti-stress, antioxidative and platelet aggregation inhibitory effects. This study was undertaken to investigate the functional properties of water extracts from four parts of A. sessiliflorus. Root, stem, leaf and fruit extracts from A. sessiliflorus were prepared with hot water (80°C). The contents of functional substances, eleutheroside B and E, polyphenol, antioxidative activity, nitrite scavenging ability and anti-cancer activity of the extracts were determined. The contents of eleutheroside E in stem, root and fruit extracts were 542.50 μg/g, 343.35 μg/g and 30.78 μg/g, respectively. A large part of eleutheroside B was found in fruit (372.01 μg/g) and root (289.33 μg/g) extracts. Root and stem extracts contained 227.21 mg/100g and 131.22 mg/100g of polyphenols, respectively. Antioxidative activities (electron donating ability) of stem and root extracts were 79.87% and 77.27%, respectively. It appears that the antioxidative activities were related to polyphenol contents of the extracts. Most extracts showed 76-81.5% of nitrite scavenging ability at pH 1.2. It reveals that water extract from parts of A. sessiliflorus can inhibit formation of nitrosoamine in food. Effects of the extracts on the growth of normal and cancer cell lines were investigated. Extracts showed no cytotoxicity to normal dendritic cell line (DC2.4). Especially, the root extract promoted the growth of normal cell line. Root and stem extracts had 20-23% of inhibitory effect against stomach cancer cell line (SNU-719) and liver cancer cell line (Hep3B). These result indicated that the extracts from A. sessiliflorus can be used as functional food materials with antioxidative activity and nitrite scavenging ability to eliminate nitrosoamine in food.

Abstract 998: Downregulation of survivin suppresses uPA through transcription factor JunB

Abstract Background: Survivin, identified member of the inhibitor apoptosis protein family, is expressed during development and in various human cancers. However, lts role of clinical relevance in cancers are sill debated. Purpose: We investigated the role of HGF induced activation of a transcription factor JunB, in the expression of survivin and uPA. Methods and Results: Genes induced by HGF were screened by using cDNA microarray technology in stomach cancer cell lines, NUGC3 and MKN28. Expression level of surviving and JunB was further confirmed by read time RT-RCR and western blot analysis. Roles of JunB and survivin in the levels of HGF induced up-regulation of uPA were measured by knock down of survivin with survivin siRNA and chromatic immuno- precipitation assay. The levels of JunB, survivin and uPA were up regulated in cells treated with HGF in a dose dependent manner. HGH-induced up regulations of JunB, surviving, and uPA were inhibited by the pretreatment with an MEK inhibitor, PD 098559. HGH-induced up-regulation of uPA were repressed by survivin knockdown. HGF enhanced the binding activity of JunB to the enhanced the binding activity of JunB to the survivin promoter in control cells, but not in the JunB-sh RNA cells. Transfection with survivin-sh RNA results in decrement of cell proliferation as determined with MTT assays. In an in vitro invasion assay, significantly fewer cells transfected with survivin sh-RNA than control cells were able to invade across a matrigel membrane barrier.Conclusion: Survivin might play an important role in the up-regulation of uPA induced by HGF via JunB and contribute to HGF-mediated tumor invasion and metastasis, which might be promising target for stomach cancer therapy. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 998. doi:10.1158/1538-7445.AM2011-998

Abstract 609: Frondoside antagonizes the prostaglandin E receptor EP4 and inhibits breast tumor metastasis

Abstract Sea cucumber has been used as a folk medicine for many conditions and recently antitumor activities have been described. Frondoside A, a triterpenoid glycoside isolated from the sea cucumber Cucumaria frondosa, as well as the related compound Frondanol A5 inhibit growth of pancreatic, colon and breast tumor cell lines in vitro and show activity in a primary prevention model of colon cancer. The cyclooxygenase 2 pathway contributes to growth and progression of many solid tumors by multiple mechanisms. The COX-2 product, prostaglandin E2 (PGE2) contributes to malignancy by acting on a family of four G-protein-coupled receptors (EP1, EP2, EP3, EP4). We have shown that both human and murine breast tumor cell lines express all EP receptors and that EP4 contributes to metastatic potential in a syngeneic murine model of metastatic breast cancer. Other laboratories have also provided evidence that EP4 promotes malignancy but a paucity of effective EP4 antagonists has slowed the development of clinically evaluable EP-targeted compounds. Based on the reported anti-inflammatory properties of Frondoside A, we asked if this compound has EP antagonist properties. We now report the novel finding that Frondoside A is a potent antagonist of EP4 and, to a lesser degree, antagonizes EP2. Frondoside A inhibits the binding of radio-labeled PGE2 to Chem-1 cells expressing EP4 or HEK cells transduced to express EP2. Using EP4-expressing MDA-MD-231 human breast cancer or murine mammary tumor cell line 66.1, we show that EP4-mediated activation of adenylate cyclase is also blocked by Frondoside A indicating both pharmacologic and functional EP4 receptor antagonism. We determined the effect of Frondoside A on metastatic potential of line 66.1 tumor cells. Treatment of 66.1 cells with non-cytotoxic concentrations of Frondoside A prior to i.v. administration of tumor cells into syngeneic Balb/cByJ female mice reduced lung colonizing capacity by 58%. These studies describe a potent metastasis inhibitory activity of Frondoside A and show, for the first time, that this compound may be a potent novel EP4/EP2 antagonist with activity in a model of metastatic breast cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 609. doi:10.1158/1538-7445.AM2011-609

Measurement of Aggregate Cohesion by Tissue Surface Tensiometry

Rigorous measurement of intercellular binding energy can only be made using methods grounded in thermodynamic principles in systems at equilibrium. We have developed tissue surface tensiometry (TST) specifically to measure the surface free energy of interaction between cells. The biophysical concepts underlying TST have been previously described in detail. The method is based on the observation that mutually cohesive cells, if maintained in shaking culture, will spontaneously assemble into clusters. Over time, these clusters will round up to form spheres. This rounding-up behavior mimics the behavior characteristic of liquid systems. Intercellular binding energy is measured by compressing spherical aggregates between parallel plates in a custom-designed tissue surface tensiometer. The same mathematical equation used to measure the surface tension of a liquid droplet is used to measure surface tension of 3D tissue-like spherical aggregates. The cellular equivalent of liquid surface tension is intercellular binding energy, or more generally, tissue cohesivity. Previous studies from our laboratory have shown that tissue surface tension (1) predicts how two groups of embryonic cells will interact with one another, (2) can strongly influence the ability of tissues to interact with biomaterials, (3) can be altered not only through direct manipulation of cadherin-based intercellular cohesion, but also by manipulation of key ECM molecules such as FN and 4) correlates with invasive potential of lung cancer, fibrosarcoma, brain tumor and prostate tumor cell lines. In this article we will describe the apparatus, detail the steps required to generate spheroids, to load the spheroids into the tensiometer chamber, to initiate aggregate compression, and to analyze and validate the tissue surface tension measurements generated.

Identification of Chrysoplenetin from Vitex negundo as a Potential Cytotoxic Agent against PANC‐1 and a Panel of 39 Human Cancer Cell Lines (JFCR‐39)

Human pancreatic cancer is known to be the most deadly disease with the lowest 5-year survival rate and is resistant to well known conventional chemotherapeutic drugs in clinical use. Screening of medicinal plants from Myanmar utilizing antiausterity strategy led to the identification of Vitex negundo as one of the medicinal plants having potent preferential cytotoxic activity against PANC-1 human pancreatic cancer cells. Bioactivity-guided phytochemical investigation led to the isolation of chrysoplenetin (1) and chrysosplenol D (2) as the active constituents with a PC(50) value of 3.4 μg/mL and 4.6 μg/mL, respectively, against PANC-1 cells. Both these compounds induced apoptosis-like morphological changes in PANC-1 cells. Chrysoplenetin was further tested against a panel of 39 human cancer cell lines (JFCR-39) at the Japanese Foundation for Cancer Research, and 25 cell lines belonging to lung, breast, CNS, colon, melanoma, ovarian, prostate cancer and stomach cancer cell lines were found to be highly sensitive to chrysoplenetin at a submicromolar range. In the JFCR-39 panel, lung NCI-H522, ovarian OVCAR-3 and prostate PC-3 cells were found to be most sensitive with GI(50) of 0.12, 0.18 and 0.17 μm, respectively. The COMPARE analysis suggested that the molecular mode of action of chrysoplenetin was unique compared with the existing anticancer drugs.

세포주를 이용한 군소 다당류와 Glycosaminoglycan의 기능성 검색

군소에서 정제한 GAG는 대식세포주인 RAW 264.7에서 세포독성은 보이지 않았으며 NO 생성량, TNF-α, IL-6 생성량을 증가시켜 면역조절 효과가 있음을 확인하였다. 그리고 100 ㎍/mL 농도에서 배양 72시간 후 약 40%에 가까운 위암세포(AGS) 성장 억제 효과가 나타났고, 정상세포 IEC-6에는 독성을 보이지 않았다. 이 같은 결과는 면역조절을 위한 기능성식품 혹은 위암 치료제로서 군소의 당 추출물과 GAG의 활용 가능성을 제시한다.

Aberrant Promoter CpG Methylation Is a Mechanism for Impaired PHD3 Expression in a Diverse Set of Malignant Cells

BackgroundThe prolyl-hydroxylase domain family of enzymes (PHD1-3) plays an important role in the cellular response to hypoxia by negatively regulating HIF-α proteins. Disruption of this process can lead to up-regulation of factors that promote tumorigenesis. We observed decreased basal expression of PHD3 in prostate cancer tissue and tumor cell lines representing diverse tissues of origin. Furthermore, some cancer lines displayed a failure of PHD3 mRNA induction when introduced to a hypoxic environment. This study explores the mechanism by which malignancies neither basally express PHD3 nor induce PHD3 under hypoxic conditions.Methodology/Principal FindingsUsing bisulfite sequencing and methylated DNA enrichment procedures, we identified human PHD3 promoter hypermethylation in prostate, breast, melanoma and renal carcinoma cell lines. In contrast, non-transformed human prostate and breast epithelial cell lines contained PHD3 CpG islands that were unmethylated and responded normally to hypoxia by upregulating PHD3 mRNA. Only treatment of cells lines containing PHD3 promoter hypermethylation with the demethylating drug 5-aza-2′-deoxycytidine significantly increased the expression of PHD3.Conclusions/SignificanceWe conclude that expression of PHD3 is silenced by aberrant CpG methylation of the PHD3 promoter in a subset of human carcinoma cell lines of diverse origin and that this aberrant cytosine methylation status is the mechanism by which these cancer cell lines fail to upregulate PHD3 mRNA. We further show that a loss of PHD3 expression does not correlate with an increase in HIF-1α protein levels or an increase in the transcriptional activity of HIF, suggesting that loss of PHD3 may convey a selective advantage in some cancers by affecting pathway(s) other than HIF.

Cytotoxic and Apoptosis-Inducing Activities of Triterpene Acids from Poria cocos

Six lanostane-type triterpene acids (1a-6a), isolated from Poria cocos , and their methyl ester (1b-6b) and hydroxy derivatives (1c-6c) were prepared. Upon evaluation of the cytotoxic activity of these compounds against leukemia (HL60), lung (A549), melanoma (CRL1579), ovary (NIH:OVCAR-3), breast (SK-BR-3), prostate (DU145), stomach (AZ521), and pancreas (PANC-1) cancer cell lines, 11 compounds (5a, 6a, 2b-5b, 1c, and 3c-6c) exhibited activity with single-digit micromolar IC(50) values against one or more cell lines. Poricotriol A (1c), a hydroxy derivative of poricoic acid A (1a), exhibited potent cytotoxicities against six cell lines with IC(50) values of 1.2-5.5 μM. Poricotriol A induced typical apoptotic cell death in HL60 and A549 cells on evaluation of the apoptosis-inducing activity by flow cytometric analysis. Western blot analysis in HL60 cells showed that poricotriol A activated caspases-3, -8, and -9, while increasing the ratio of Bax/Bcl-2. This suggested that poricotriol A induced apoptosis via both mitochondrial and death receptor pathways in HL60. On the other hand, poricotriol A did not activate caspases-3, -8, and -9, but induced translocation of apoptosis-inducing factor (AIF) from mitochondria and increased the ratio of Bax/Bcl-2 in A549. This suggested that poricotriol A induced apoptosis via the mitochondrial pathway mostly by translocation of AIF, independent from the caspase pathway in A549. Furthermore, poricotriol A was shown to possess high selective toxicity in lung cancer cells since it exhibited only weak cytotoxicity against a normal lung cell line (WI-38).

Down-regulation of survivin suppresses uro-plasminogen activator through transcription factor JunB

Survivin, a member of the inhibitors of apoptosis protein family, is expressed during development and in various human cancers. However, the clinical relevance of survivin in cancer is still a matter of debate. Genes induced by hepatocyte growth factor (HGF) were screened using cDNA microarray technology in the stomach cancer cell lines, NUGC3 and MKN28. The levels of JunB, survivin, and uro-plasminogen activator (uPA) were up-regulated in cells treated with HGF in a dose-dependent manner. HGF-induced up regulation of JunB, survivin, and uPA was inhibited by pre-treatment with a MEK inhibitor (PD 98059). HGF-induced up-regulation of uPA was repressed by survivin knockdown. HGF enhanced the binding activity of JunB to the survivin promoter in control cells, but not in the JunB-shRNA cells. Transfection with survivin- shRNA resulted in a decrement of cell proliferation, as determined with MTT assays. In an in vitro invasion assay, significantly fewer cells transfected with survivin shRNA than control cells were able to invade across a Matrigel membrane barrier. In conclusion, survivin appeared to play an important role in the up-regulation of uPA induced by HGF via JunB and might contribute to HGF-mediated tumor invasion and metastasis, which may serve as a promising target for gastric cancer therapy.

Identification of CM1 as a Pathogenic Factor in Inflammatory Diseases and Cancer

BackgroundCM1 (centrocyte/-blast marker 1) was defined by a mAb against concanavalin A (Con A) activated PBMC. It is expressed in germinal center of human tonsil and on the surface of activated PBMC as well as cancer cells. Recently, increased productions of pro-inflammatory mediators were detected from activated PBMC by CM1 ligation.MethodsHowever, there is a limitation to explain the exact role of CM1 on inflammation and its related mechanisms, since the identity of CM1 is still not clarified. In our previous study, we have already confirmed that soluble form of CM1 was produced by Raji. Therefore, we performed Q-TOF analysis after immunoprecipitation of concentrated Raji culture supernatant using anti-CM1 mAbs.ResultsAs a result, we found that CM1 is identical to enolase-1(ENO1), a glycolytic enzyme, and we confirmed that results by silencing ENO1 using siRNA. It was also confirmed through competition assay between anti-CM1 and anti-ENO1 mAbs. Finally, we investigated the possible role of CM1 in inflammatory response and cancer. The ligation of CM1 on Raji cells with anti-CM1 mAbs induces the extensive production of prostaglandin E2(PGE2). In addition, the increased activity of matrix metalloproteinase (MMP)-2/9 was shown in NCI-N87, stomach cancer cell line by CM1 stimulation.ConclusionCM1 is identical to ENO1 and it might be an important role in the regulation of inflammatory responses.

Aromatic constituents of Heteroplexis micocephal and their bioactivities

To investigate the chemical constituents of Heteroplexis micocephal and their bioactivities. The constituents were isolated by using a combination of various chromatographic techniques including column chromatography over macroporous adsorbent resin, silica gel, Pharmadex LH-20, and C-18, as well as reversed-phase HPLC. Structures of the isolates were identified by spectroscopic data analysis. In vitro cytotoxic, HIV-1 replication, neuroprotective, and anti-inflammatory activities were screened by using cell-based models. Thirty-one compounds were obtained. Twelve of them are phenylpropanols, and the structures were elucidated as (+)-(7S,8R)-guaiacylglycerol (1), ferulic acid (2), cinnamate methyl ester (3), 1-eicosanyl 3,4-dihydroxycinnamate (4), morinin B (5), sinapyl diangelate (6), chlorogenic acid (7), 4-O-caffeoylquinic acid (8), 5-O-caffeoylquinic acid (9), 5-O-caffeoylquinic acid methyl ester (10), 1,5-di-O-caffeoylquinic acid (11) and 4,5-di-O-caffeoylquinic acid methyl ester (12). Three lignans, (+)-pinoresinol (13), prinsepiol (14) and (+)-pinoresinol-O-beta-D-glucopyranoside (15). Four acetophenones, 2,4-diacetylanisole (16), espeleton (17), viscidone (18) and 12-hydroxytremetone-12-O-beta-D-glucopyranoside (19). Nine flavones, isosakuranetin (20), hesperetin (21), 3-methoxy-5,7,3',4'-tetrahydroxyflavone (22), acacetin (23), 5-hydroxy-7,4'- dimethoxyflavone (24), 7-methoxy-4',5, 6-trihydroxyflavone (25), 3,3'-dimethylquercetin (26), kaempferol 3-O-rutinoside (27), rutin (28). And three coumarins scopoletin (29), umbelliferone (30) and ayapin (31). Compound 6 and 22 showed selective cytotoxicities against a human stomach cancer cell line(BGC-823) and a human lung cancer cell line (A549) with IC50 values of 3.74 x 10(-5) and 7.17 x 10(-5) mol L(-1), respectively. In addition, Compound 6 showed a potent activity inhibiting HIV-1 replication with an IC50 value of 4.04 x 10(-6) mol L(-1), while 22 showed neuroprotective activity Against the MPP+ induced PC12-syn cell damage, with a relative protection ratio of 105.2% (P < 0.01) at a concentration of 10(-5) mol L(-1). Compound 26 and 31 showed inhibitory activities against the release of beta-glucuronidase of the polymorphous nuclear leukocytes induced by platelet activating factor (PAF), with inhibitory rates of 75.6% (P < 0.001) and 53. 9% (P < 0.01), respectively. Compounds 1-31 were obtained from the genus Heteroplexis for the first time. Compound 6 and 22 possessed selective cytotoxicities against human cancer cell lines BGC-823 and A549, respectively. In addition, Compound 6 showed a potent activity inhibiting HIV-1 replication while 22 showed neuroprotective activity against the MPP+ induced PC12-syn cell damage. Compound 26 and 31 were potent anti-inflammatory agents.

The Anti-tumor Activity of Vitamin C via the Increase of Fas (CD95) and MHC I Expression on Human Stomach Cancer Cell Line, SNU1

BackgroundIt is already known that high concentration of vitamin C induces apoptosis on tumor cells. However, there is no report regarding the function of vitamin C on the modulation of immune susceptibility of cancer. Therefore, we investigated whether vitamin C can modulate immune susceptibility of tumor cells, especially on the induction of Fas-mediated apoptosis.MethodsFirst, the optimal concentration of vitamin C, which cannot induce damages on tumor cells for 36 hrs. We found that 2 mM of vitamin C did not show harmful effect. In addition, the optimal concentration of agonistic anti-Fas Abs for 18 hrs was examined.ResultsAs a result, 400 ng/ml of agonistic anti-Fas Abs did not induce apoptosis on tumor cells. Next, we tried to find the effect of 2 mM of vitamin C on the modulation of the susceptibility to agonistic anti-Fas Abs. When tumor cells were cultured with 400 ng/ml of agonistic anti-Fas Abs for 18 hrs, after pre-treatment with 2 mM of vitamin C for 24 hrs, viability of cells was decreased. Interestingly, we found that the expression of Fas (CD95) and MHC class I was increased by the treatment of vitamin C.ConclusionTaken together, vitamin C increases the susceptibility of tumor cells to anti-Fas Abs and the expression of Fas (CD95) and MHC class I on tumor cells.

Isolation, Structure Elucidation, and Cytotoxic Evaluation of Furanonaphthoquinones from in Vitro Plantlets and Cultures of Streptocarpus dunnii

Two new furanonaphthoquinones, (3R)-7-methoxy-α-dunnione (5) and (3R)-6-hydroxy-7-methoxy-α-dunnione (6), along with the known (3R)-dunnione (1), (3R)-α-dunnione (2), (3R)-7-hydroxy-α-dunnione (3), and 1-hydroxy-2-methylanthraquinone (4), were isolated from in vitro cultures of Streptocarpus dunnii. The structures of compounds 5 and 6 were established by spectroscopic means. This is the first report of hydroxylated furanonaphthoquinones in a Streptocarpus species. Compounds 1-3 demonstrated cytotoxic activity against a range of breast cancer and pancreatic tumor cell lines.

De novo expression of CD44 variants in sporadic and hereditary gastric cancer

CD44 is the major ubiquitously expressed cell surface receptor for hyaluronate. The CD44 gene encodes several protein isoforms due to extensive alternative splicing and post-translational modifications. Some of these CD44 variable isoforms have been foreseen as key players in malignant transformation and their expression is highly restricted and highly specific, unlike the canonical CD44 standard isoform. In this study, we aimed at dissecting the mRNA splicing pattern of CD44 in normal stomach and gastric cancer (GC) cell lines (n=9) using cloning and quantitative mRNA amplification assays. Moreover, we assessed the RNA levels and protein expression pattern of relevant splicing forms in distinct premalignant and malignant gastric lesions (sporadic (n=43) and hereditary (n=3) forms) using real-time RT-PCR and immunohistochemistry. We also explored the association of CD44 and E-cadherin expression by immunohistochemistry, as E-cadherin has a pivotal functional role in GC. We established the pattern of CD44 variant forms in normal stomach and gastric malignancy. We observed that although exon v6-containing isoforms were rarely expressed in normal gastric mucosa, they became increasingly expressed both in gastric premalignant (hyperplastic polyps, complete and incomplete intestinal metaplasia, low- and high-grade dysplasia) and malignant lesions (cell lines derived from GCs, primary sporadic GCs and hereditary diffuse GCs (HDGCs)). Moreover, we verified that whenever E-cadherin expression was absent, exon v6-containing CD44 isoforms were overexpressed. The lack of expression of CD44 isoforms containing exon v6 in the surface and foveolar epithelia of normal stomach and, its de novo expression in premalignant, as well as in sporadic and hereditary malignant lesions of the stomach, pinpoint CD44 v6-containg isoforms as potential biomarkers for early transformation of the gastric mucosa. Further, our results raise the hypothesis of using CD44v6 as a marker of early invasive intramucosal carcinoma in HDGC CDH1 mutation carriers that lack CDH1 expression in their tumors.