2-Dodecylcyclobutanone, a radiolytic product of palmitic acid, is genotoxic in primary human colon cells and in cells from preneoplastic lesions

International Nuclear Information System (INIS)

Knoll, Nadine; Weise, Anja; Claussen, Uwe; Sendt, Wolfgang; Marian, Brigitte; Glei, Michael; Pool-Zobel, Beatrice L.

2006-01-01

The irradiation of fat results in the formation of 2-alkylcyclobutanones, a new class of food contaminants. Results of previous in vitro studies with primary human colon cells and in vivo experiments with rats fed with 2-alkylcyclobutanones indicated that these radiolytic derivatives may be genotoxic and enhance the progression of colon tumors. The underlying mechanisms of these effects, however, are not clearly understood. Therefore we performed additional investigations to elucidate the genotoxic potential of 2-dodecylcyclobutanone (2dDCB) that is generated from palmitic acid. In particular, we explored the relative sensitivities of human colon cells, representing different stages of tumor development and healthy colon tissues, respectively. HT29clone19A cells, LT97 adenoma cells and primary human epithelial cells were exposed to 2dDCB (150-2097 μM). We determined cytotoxic effects using trypan blue exclusion. Genotoxicity, reflected as strand breaks, was assessed using the alkaline version of the comet assay and chromosomal abnormalities were investigated by 24-color fluorescence-in-situ-hybridization. 2dDCB was cytotoxic in a time- and dose-dependent manner in LT97 adenoma cells and in freshly isolated primary cells but not in the human colon tumor cell line. Associated with this was a marked induction of DNA damage by 2dDCB in LT97 adenoma cells and in freshly isolated colonocytes, whereas in the HT29clone19A cells no strand breaks were detectable. A long-term incubation of LT97 adenoma cells with lower concentrations of 2dDCB revealed cytogenetic effects. In summary, 2dDCB was clearly genotoxic in healthy human colon epithelial cells and in cells representing preneoplastic colon adenoma. These findings provide additional evidence that this compound may be regarded as a possible risk factor for processes in colon carcinogenesis related to initiation and progression

Cell surface glycopeptides from human intestinal epithelial cell lines derived from normal colon and colon adenocarcinomas

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Youakim, A.; Herscovics, A.

1985-01-01

The cell surface glycopeptides from an epithelial cell line (CCL 239) derived from normal human colon were compared with those from three cell lines (HCT-8R, HCT-15, and CaCo-2) derived independently from human colonic adenocarcinomas. Cells were incubated with D-[2- 3 H]mannose or L-[5,6- 3 H]fucose for 24 h and treated with trypsin to release cell surface components which were then digested exhaustively with Pronase and fractionated on Bio-Gel P-6 before and after treatment with endo-beta-N-acetylglucosaminidase H. The most noticeable difference between the labeled glycopeptides from the tumor and CCL 239 cells was the presence in the former of an endo-beta-N-acetylglucosaminidase H-resistant high molecular weight glycopeptide fraction which was eluted in the void volume of Bio-Gel P-6. This fraction was obtained with both labeled mannose and fucose as precursors. However, acid hydrolysis of this fraction obtained after incubation with [2- 3 H]mannose revealed that as much as 60-90% of the radioactivity was recovered as fucose. Analysis of the total glycopeptides (cell surface and cell pellet) obtained after incubation with [2- 3 H]mannose showed that from 40-45% of the radioactivity in the tumor cells and less than 10% of the radioactivity in the CCL 239 cells was recovered as fucose. After incubation of the HCT-8R cells with D-[1,6- 3 H]glucosamine and L-[1- 14 C]fucose, strong acid hydrolysis of the labeled glycopeptide fraction excluded from Bio-Gel P-6 produced 3 H-labeled N-acetylglucosamine and N-acetylgalactosamine

Human colon cancer HT-29 cell death responses to doxorubicin and Morus Alba leaves flavonoid extract.

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Fallah, S; Karimi, A; Panahi, G; Gerayesh Nejad, S; Fadaei, R; Seifi, M

2016-03-31

The mechanistic basis for the biological properties of Morus alba flavonoid extract (MFE) and chemotherapy drug of doxorubicin on human colon cancer HT-29 cell line death are unknown. The effect of doxorubicin and flavonoid extract on colon cancer HT-29 cell line death and identification of APC gene expression and PARP concentration of HT-29 cell line were investigated. The results showed that flavonoid extract and doxorubicin induce a dose dependent cell death in HT-29 cell line. MFE and doxorubicin exert a cytotoxic effect on human colon cancer HT-29 cell line by probably promoting or induction of apoptosis.

MicroRNA-320a suppresses human colon cancer cell proliferation by directly targeting β-catenin

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Sun, Jian-Yong; Huang, Yi; Li, Ji-Peng; Zhang, Xiang; Wang, Lei; Meng, Yan-Ling; Yan, Bo; Bian, Yong-Qian; Zhao, Jing; Wang, Wei-Zhong

2012-01-01

Highlights: ► miR-320a is downregulated in human colorectal carcinoma. ► Overexpression of miR-320a inhibits colon cancer cell proliferation. ► β-Catenin is a direct target of miR-320a in colon cancer cells. ► miR-320a expression inversely correlates with mRNA expression of β-catenin’s target genes in human colon carcinoma. -- Abstract: Recent profile studies of microRNA (miRNA) expression have documented a deregulation of miRNA (miR-320a) in human colorectal carcinoma. However, its expression pattern and underlying mechanisms in the development and progression of colorectal carcinoma has not been elucidated clearly. Here, we performed real-time PCR to examine the expression levels of miR-320a in colon cancer cell lines and tumor tissues. And then, we investigated its biological functions in colon cancer cells by a gain of functional strategy. Further more, by the combinational approaches of bioinformatics and experimental validation, we confirmed target associations of miR-320a in colorectal carcinoma. Our results showed that miR-320a was frequently downregulated in cancer cell lines and colon cancer tissues. And we demonstrated that miR-320a restoration inhibited colon cancer cell proliferation and β-catenin, a functionally oncogenic molecule was a direct target gene of miR-320a. Finally, the data of real-time PCR showed the reciprocal relationship between miR-320a and β-catenin’s downstream genes in colon cancer tissues. These findings indicate that miR-320a suppresses the growth of colon cancer cells by directly targeting β-catenin, suggesting its application in prognosis prediction and cancer treatment.

MicroRNA-320a suppresses human colon cancer cell proliferation by directly targeting {beta}-catenin

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Sun, Jian-Yong [State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, 710032 Xi' an (China); State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 710032 Xi' an (China); Huang, Yi [Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, 710032 Xi' an (China); Li, Ji-Peng [State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 710032 Xi' an (China); Zhang, Xiang; Wang, Lei [State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, 710032 Xi' an (China); Meng, Yan-Ling [Department of Immunology, Fourth Military Medical University, 710032 Xi' an (China); Yan, Bo [State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, 710032 Xi' an (China); Bian, Yong-Qian [State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 710032 Xi' an (China); Zhao, Jing [State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, 710032 Xi' an (China); Wang, Wei-Zhong, E-mail: weichang@fmmu.edu.cn [State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 710032 Xi' an (China); and others

2012-04-20

Highlights: Black-Right-Pointing-Pointer miR-320a is downregulated in human colorectal carcinoma. Black-Right-Pointing-Pointer Overexpression of miR-320a inhibits colon cancer cell proliferation. Black-Right-Pointing-Pointer {beta}-Catenin is a direct target of miR-320a in colon cancer cells. Black-Right-Pointing-Pointer miR-320a expression inversely correlates with mRNA expression of {beta}-catenin's target genes in human colon carcinoma. -- Abstract: Recent profile studies of microRNA (miRNA) expression have documented a deregulation of miRNA (miR-320a) in human colorectal carcinoma. However, its expression pattern and underlying mechanisms in the development and progression of colorectal carcinoma has not been elucidated clearly. Here, we performed real-time PCR to examine the expression levels of miR-320a in colon cancer cell lines and tumor tissues. And then, we investigated its biological functions in colon cancer cells by a gain of functional strategy. Further more, by the combinational approaches of bioinformatics and experimental validation, we confirmed target associations of miR-320a in colorectal carcinoma. Our results showed that miR-320a was frequently downregulated in cancer cell lines and colon cancer tissues. And we demonstrated that miR-320a restoration inhibited colon cancer cell proliferation and {beta}-catenin, a functionally oncogenic molecule was a direct target gene of miR-320a. Finally, the data of real-time PCR showed the reciprocal relationship between miR-320a and {beta}-catenin's downstream genes in colon cancer tissues. These findings indicate that miR-320a suppresses the growth of colon cancer cells by directly targeting {beta}-catenin, suggesting its application in prognosis prediction and cancer treatment.

Boletus edulis ribonucleic acid - a potent apoptosis inducer in human colon adenocarcinoma cells.

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Lemieszek, Marta Kinga; Ribeiro, Miguel; Guichard Alves, Helena; Marques, Guilhermina; Nunes, Fernando Milheiro; Rzeski, Wojciech

2016-07-13

Despite the large popularity of the Boletus edulis mushroom, little is known about its influence on human health and the possibilities of its therapeutic use. Nevertheless, several reports revealed the usefulness of biopolymers isolated from it in cancer treatment. Our previous studies have shown that B. edulis water soluble biopolymers are not toxic against normal colon epithelial cells (CCD841 CoTr) and at the same concentration range elicited a very prominent antiproliferative effect in colon cancer cells (LS180) which was accompanied with cell cycle arrest in the G0/G1 phase. The purpose of the present study was to verify the proapoptotic properties of a selected fraction from B. edulis - BE3, as well as determine its chemical nature. The BE3 fraction was extracted with hot water and purified by anion-exchange chromatography. Further chemical examinations revealed that BE3 consists mainly of ribonucleic acid (59.1%). The ability of BE3 to induce programmed cell death was examined in human colon cancer cell lines LS180 and HT-29 by measuring caspase activation, DNA fragmentation and expression of BAX, BCL2, TP53 and CDKN1A genes. The sensitivity of colon cancer cells with silenced BAX, TP53 and CDKN1A expression to BE3 treatment was also evaluated. We have demonstrated for the first time that the BE3 fraction is a potent apoptosis inducer in human colon cancer cells. The revealed mechanism of apoptosis triggering was dependent on the presence of functional p53 and consequently was a little different in investigated cell lines. Our results indicated that BE3 stimulated proapoptotic genes BAX (LS180, HT-29), TP53 (LS180) and CDKN1A (HT-29) while at the same time silenced the expression of the key prosurvival gene BCL2 (LS180, HT-29). The obtained results indicate the high therapeutic potential of the BE3 fraction against colon cancer, yet it is necessary to further confirm fraction efficacy and safety in animal and clinical studies.

Perivascular Interstitial Cells of Cajal in Human ColonSummary

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Yuan-An Liu

2015-01-01

Full Text Available Background & Aims: Interstitial cells of Cajal (ICC closely associate with nerves and smooth muscles to modulate gut motility. In the ICC microenvironment, although the circulating hormones/factors have been shown to influence ICC activities, the association between ICC and microvessels in the gut wall has not been described. We applied three-dimensional (3D vascular histology with c-kit staining to identify the perivascular ICC and characterize their morphologic and population features in the human colon wall. Methods: Full-thickness colons were obtained from colectomies performed for colorectal cancer. We targeted the colon wall away from the tumor site. Confocal microscopy with optical clearing (use of immersion solution to reduce scattering in optical imaging was performed to simultaneously reveal the ICC and vascular networks in space. 3D image rendering and projection were digitally conducted to illustrate the ICC–vessel contact patterns. Results: Perivascular ICC were identified in the submucosal border, myenteric plexus, and circular and longitudinal muscles via high-definition 3D microscopy. Through in-depth image projection, we specified two contact patterns—the intimate cell body-to-vessel contact (type I, 18% of ICC in circular muscle and the long-distance process-to-vessel contact (type II, 16%—to classify perivascular ICC. Particularly, type I perivascular ICC were detected with elevated c-kit staining levels and were routinely found in clusters, making them readily distinguishable from other ICC in the network. Conclusions: We propose a new subclass of ICC that closely associates with microvessels in the human colon. Our finding suggests a functional relationship between these mural ICC and microvessels based on the morphologic proximity. Keywords: 3D Histology, c-kit, ICC, Mural Cells

Decorin in Human Colon Cancer: Localization In Vivo and Effect on Cancer Cell Behavior In Vitro.

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Nyman, Marie C; Sainio, Annele O; Pennanen, Mirka M; Lund, Riikka J; Vuorikoski, Sanna; Sundström, Jari T T; Järveläinen, Hannu T

2015-09-01

Decorin is generally recognized as a tumor suppressing molecule. Nevertheless, although decorin has been shown to be differentially expressed in malignant tissues, it has often remained unclear whether, in addition to non-malignant stromal cells, cancer cells also express it. Here, we first used two publicly available databases to analyze the current information about decorin expression and immunoreactivity in normal and malignant human colorectal tissue samples. The analyses demonstrated that decorin expression and immunoreactivity may vary in cancer cells of human colorectal tissues. Therefore, we next examined decorin expression in normal, premalignant and malignant human colorectal tissues in more detail using both in situ hybridization and immunohistochemistry for decorin. Our results invariably demonstrate that malignant cells within human colorectal cancer tissues are devoid of both decorin mRNA and immunoreactivity. Identical results were obtained for cells of neuroendocrine tumors of human colon. Using RT-qPCR, we showed that human colon cancer cell lines are also decorin negative, in accordance with the above in vivo results. Finally, we demonstrate that decorin transduction of human colon cancer cell lines causes a significant reduction in their colony forming capability. Thus, strategies to develop decorin-based adjuvant therapies for human colorectal malignancies are highly rational. © The Author(s) 2015.

Quantification of Crypt and Stem Cell Evolution in the Normal and Neoplastic Human Colon

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Ann-Marie Baker

2014-08-01

Full Text Available Human intestinal stem cell and crypt dynamics remain poorly characterized because transgenic lineage-tracing methods are impractical in humans. Here, we have circumvented this problem by quantitatively using somatic mtDNA mutations to trace clonal lineages. By analyzing clonal imprints on the walls of colonic crypts, we show that human intestinal stem cells conform to one-dimensional neutral drift dynamics with a “functional” stem cell number of five to six in both normal patients and individuals with familial adenomatous polyposis (germline APC−/+. Furthermore, we show that, in adenomatous crypts (APC−/−, there is a proportionate increase in both functional stem cell number and the loss/replacement rate. Finally, by analyzing fields of mtDNA mutant crypts, we show that a normal colon crypt divides around once every 30–40 years, and the division rate is increased in adenomas by at least an order of magnitude. These data provide in vivo quantification of human intestinal stem cell and crypt dynamics.

Time- and dose-dependent effects of curcumin on gene expression in human colon cancer cells

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van Erk Marjan J

2004-05-01

Full Text Available Abstract Background Curcumin is a spice and a coloring food compound with a promising role in colon cancer prevention. Curcumin protects against development of colon tumors in rats treated with a colon carcinogen, in colon cancer cells curcumin can inhibit cell proliferation and induce apoptosis, it is an anti-oxidant and it can act as an anti-inflammatory agent. The aim of this study was to elucidate mechanisms and effect of curcumin in colon cancer cells using gene expression profiling. Methods Gene expression changes in response to curcumin exposure were studied in two human colon cancer cell lines, using cDNA microarrays with four thousand human genes. HT29 cells were exposed to two different concentrations of curcumin and gene expression changes were followed in time (3, 6, 12, 24 and 48 hours. Gene expression changes after short-term exposure (3 or 6 hours to curcumin were also studied in a second cell type, Caco-2 cells. Results Gene expression changes (>1.5-fold were found at all time points. HT29 cells were more sensitive to curcumin than Caco-2 cells. Early response genes were involved in cell cycle, signal transduction, DNA repair, gene transcription, cell adhesion and xenobiotic metabolism. In HT29 cells curcumin modulated a number of cell cycle genes of which several have a role in transition through the G2/M phase. This corresponded to a cell cycle arrest in the G2/M phase as was observed by flow cytometry. Functional groups with a similar expression profile included genes involved in phase-II metabolism that were induced by curcumin after 12 and 24 hours. Expression of some cytochrome P450 genes was downregulated by curcumin in HT29 and Caco-2 cells. In addition, curcumin affected expression of metallothionein genes, tubulin genes, p53 and other genes involved in colon carcinogenesis. Conclusions This study has extended knowledge on pathways or processes already reported to be affected by curcumin (cell cycle arrest, phase

Fem1b, a proapoptotic protein, mediates proteasome inhibitor-induced apoptosis of human colon cancer cells.

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Subauste, M Cecilia; Sansom, Owen J; Porecha, Nehal; Raich, Natacha; Du, Liqin; Maher, Joseph F

2010-02-01

In the treatment of colon cancer, the development of resistance to apoptosis is a major factor in resistance to therapy. New molecular approaches to overcome apoptosis resistance, such as selectively upregulating proapoptotic proteins, are needed in colon cancer therapy. In a mouse model with inactivation of the adenomatous polyposis coli (Apc) tumor suppressor gene, reflecting the pathogenesis of most human colon cancers, the gene encoding feminization-1 homolog b (Fem1b) is upregulated in intestinal epithelium following Apc inactivation. Fem1b is a proapoptotic protein that interacts with apoptosis-inducing proteins Fas, tumor necrosis factor receptor-1 (TNFR1), and apoptotic protease activating factor-1 (Apaf-1). Increasing Fem1b expression induces apoptosis of cancer cells, but effects on colon cancer cells have not been reported. Fem1b is a homolog of feminization-1 (FEM-1), a protein in Caenorhabditis elegans that is regulated by proteasomal degradation, but whether Fem1b is likewise regulated by proteasomal degradation is unknown. Herein, we found that Fem1b protein is expressed in primary human colon cancer specimens, and in malignant SW620, HCT-116, and DLD-1 colon cancer cells. Increasing Fem1b expression, by transfection of a Fem1b expression construct, induced apoptosis of these cells. We found that proteasome inhibitor treatment of SW620, HCT-116, and DLD-1 cells caused upregulation of Fem1b protein levels, associated with induction of apoptosis. Blockade of Fem1b upregulation with morpholino antisense oligonucleotide suppressed the proteasome inhibitor-induced apoptosis of these cells. In conclusion, the proapoptotic protein Fem1b is downregulated by the proteasome in malignant colon cancer cells and mediates proteasome inhibitor-induced apoptosis of these cells. Therefore, Fem1b could represent a novel molecular target to overcome apoptosis resistance in therapy of colon cancer.

Inactivation of Adenomatous Polyposis Coli Reduces Bile Acid/Farnesoid X Receptor Expression through Fxr gene CpG Methylation in Mouse Colon Tumors and Human Colon Cancer Cells.

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Selmin, Ornella I; Fang, Changming; Lyon, Adam M; Doetschman, Tom C; Thompson, Patricia A; Martinez, Jesse D; Smith, Jeffrey W; Lance, Peter M; Romagnolo, Donato F

2016-02-01

The farnesoid X receptor (FXR) regulates bile acid (BA) metabolism and possesses tumor suppressor functions. FXR expression is reduced in colorectal tumors of subjects carrying inactivated adenomatous polyposis coli (APC). Identifying the mechanisms responsible for this reduction may offer new molecular targets for colon cancer prevention. We investigated how APC inactivation influences the regulation of FXR expression in colonic mucosal cells. We hypothesized that APC inactivation would epigenetically repress nuclear receptor subfamily 1, group H, member 4 (FXR gene name) expression through increased CpG methylation. Normal proximal colonic mucosa and normal-appearing adjacent colonic mucosa and colon tumors were collected from wild-type C57BL/6J and Apc-deficient (Apc(Min) (/+)) male mice, respectively. The expression of Fxr, ileal bile acid-binding protein (Ibabp), small heterodimer partner (Shp), and cyclooxygenase-2 (Cox-2) were determined by real-time polymerase chain reaction. In both normal and adjacent colonic mucosa and colon tumors, we measured CpG methylation of Fxr in bisulfonated genomic DNA. In vitro, we measured the impact of APC inactivation and deoxycholic acid (DCA) treatment on FXR expression in human colon cancer HCT-116 cells transfected with silencing RNA for APC and HT-29 cells carrying inactivated APC. In Apc(Min) (/+) mice, constitutive CpG methylation of the Fxrα3/4 promoter was linked to reduced (60-90%) baseline Fxr, Ibabp, and Shp and increased Cox-2 expression in apparently normal adjacent mucosa and colon tumors. Apc knockdown in HCT-116 cells increased cellular myelocytomatosis (c-MYC) and lowered (∼50%) FXR expression, which was further reduced (∼80%) by DCA. In human HCT-116 but not HT-29 colon cancer cells, DCA induced FXR expression and lowered CpG methylation of FXR. We conclude that the loss of APC function favors the silencing of FXR expression through CpG hypermethylation in mouse colonic mucosa and human colon cells

Effect of sulindac sulfide on metallohydrolases in the human colon cancer cell line HT-29.

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Hector Guillen-Ahlers

Full Text Available Matrix metalloproteinase 7 (MMP7, a metallohydrolase involved in the development of several cancers, is downregulated in the Apc(Min/+ colon cancer mouse model following sulindac treatment. To determine whether this effect is relevant to the human condition, HT-29 human colon cancer cells were treated with sulindac and its metabolites, and compared to results obtained from in vivo mouse studies. The expression of MMP7 was monitored. The results demonstrated that sulindac sulfide effectively downregulated both MMP7 expression and activity. Furthermore, activity-based proteomics demonstrated that sulindac sulfide dramatically decreased the activity of leukotriene A4 hydrolase in HT-29 cells as reflected by a decrease in the level of its product, leukotriene B4. This study demonstrates that the effect of sulindac treatment in a mouse model of colon cancer may be relevant to the human counterpart and highlights the effect of sulindac treatment on metallohydrolases.

Genistein induces G2/M cell cycle arrest and apoptosis via ATM/p53-dependent pathway in human colon cancer cells.

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Zhang, Zhiyu; Wang, Chong-Zhi; Du, Guang-Jian; Qi, Lian-Wen; Calway, Tyler; He, Tong-Chuan; Du, Wei; Yuan, Chun-Su

2013-07-01

Soybean isoflavones have been used as a potential preventive agent in anticancer research for many years. Genistein is one of the most active flavonoids in soybeans. Accumulating evidence suggests that genistein alters a variety of biological processes in estrogen-related malignancies, such as breast and prostate cancers. However, the molecular mechanism of genistein in the prevention of human colon cancer remains unclear. Here we attempted to elucidate the anticarcinogenic mechanism of genistein in human colon cancer cells. First we evaluated the growth inhibitory effect of genistein and two other isoflavones, daidzein and biochanin A, on HCT-116 and SW-480 human colon cancer cells. In addition, flow cyto-metry was performed to observe the morphological changes in HCT-116/SW-480 cells undergoing apoptosis or cell cycle arrest, which had been visualized using Annexin V-FITC and/or propidium iodide staining. Real-time PCR and western blot analyses were also employed to study the changes in expression of several important genes associated with cell cycle regulation. Our data showed that genistein, daidzein and biochanin A exhibited growth inhibitory effects on HCT-116/SW-480 colon cancer cells and promoted apoptosis. Genistein showed a significantly greater effect than the other two compounds, in a time- and dose-dependent manner. In addition, genistein caused cell cycle arrest in the G2/M phase, which was accompanied by activation of ATM/p53, p21waf1/cip1 and GADD45α as well as downregulation of cdc2 and cdc25A demonstrated by q-PCR and immunoblotting assay. Interestingly, genistein induced G2/M cell cycle arrest in a p53-dependent manner. These findings exemplify that isoflavones, especially genistein, could promote colon cancer cell growth inhibition and facilitate apoptosis and cell cycle arrest in the G2/M phase. The ATM/p53-p21 cross-regulatory network may play a crucial role in mediating the anticarcinogenic activities of genistein in colon cancer.

STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH+/CD133+ stem cell-like human colon cancer cells

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Lin, Li; Fuchs, James; Li, Chenglong; Olson, Veronica; Bekaii-Saab, Tanios; Lin, Jiayuh

2011-01-01

Highlights: ► The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. ► STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. ► Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. ► STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. ► Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH + /CD133 + ). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower IC50 in colon cancer stem-like cells. In summary, our results indicate that STAT3 is a novel therapeutic target in colon cancer stem

The cardiac glycoside oleandrin induces apoptosis in human colon cancer cells via the mitochondrial pathway.

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Pan, Li; Zhang, Yuming; Zhao, Wanlu; Zhou, Xia; Wang, Chunxia; Deng, Fan

2017-07-01

Evidence indicates that the cardiac glycoside oleandrin exhibits cytotoxic activity against several different types of cancer. However, the specific mechanisms underlying oleandrin-induced anti-tumor effects remain largely unknown. The present study examined the anti-cancer effect and underlying mechanism of oleandrin on human colon cancer cells. The cytotoxicity and IC50 of five small molecule compounds (oleandrin, neriifolin, strophanthidin, gitoxigenin, and convallatoxin) in human colon cancer cell line SW480 cells and normal human colon cell line NCM460 cells were determined by cell counting and MTT assays, respectively. Apoptosis was determined by staining cells with annexin V-FITC and propidium iodide, followed by flow cytometry. Intracellular Ca 2+ was determined using Fluo-3 AM,glutathione (GSH) levels were measured using a GSH detection kit,and the activity of caspase-3, -9 was measured using a peptide substrate. BAX, pro-caspase-3, -9, cytochrome C and BCL-2 expression were determined by Western blotting. Oleandrin significantly decreased cell viabilities in SW480, HCT116 and RKO cells. The IC50 for SW480 cells was 0.02 µM, whereas for NCM460 cells 0.56 µM. More interestingly, the results of flow cytometry showed that oleandrin potently induced apoptosis in SW480 and RKO cells. Oleandrin downregulated protein expression of pro-caspase-3, -9, but enhanced caspase-3, -9 activities. These effects were accompanied by upregulation of protein expression of cytochrome C and BAX, and downregulation of BCL-2 protein expression in a concentration-dependent manner. Furthermore, oleandrin increased intracellular Ca 2+ concentration, but decreased GSH concentration in the cells. The present results suggest that oleandrin induces apoptosis in human colorectal cancer cells via the mitochondrial pathway. Our findings provide new insight into the mechanism of anti-cancer property of oleandrin.

Chemopreventive effects of in vitro digested and fermented bread in human colon cells.

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Schlörmann, Wiebke; Hiller, Beate; Jahns, Franziska; Zöger, Romy; Hennemeier, Isabell; Wilhelm, Anne; Lindhauer, Meinolf G; Glei, Michael

2012-10-01

Bread as a staple food product represents an important source for dietary fibre consumption. Effects of wheat bread, wholemeal wheat bread and wholemeal rye bread on mechanisms which could have impact on chemoprevention were analysed in colon cells after in vitro fermentation. Effects of fermented bread samples on gene expression, glutathione S-transferase activity and glutathione content, differentiation, growth and apoptosis were investigated using the human colon adenoma cell line LT97. Additionally, apoptosis was studied in normal and tumour colon tissue by determination of caspase activities. The expression of 76 genes (biotransformation, differentiation, apoptosis) was significantly upregulated (1.5-fold) in LT97 cells. The fermented bread samples were able to significantly increase glutathione S-transferase activity (1.8-fold) and glutathione content (1.4-fold) of the cells. Alkaline phosphatase activity as a marker of differentiation was also significantly enhanced (1.7-fold). The fermented bread samples significantly inhibited LT97 cell growth and increased the level of apoptotic cells (1.8-fold). Only marginal effects on apoptosis in tumour compared to normal tissue were observed. This is the first study which presents chemopreventive effects of different breads after in vitro fermentation. In spite of differences in composition, the results were comparable between the bread types. Nevertheless, they indicate a potential involvement of this staple food product regarding the prevention of colon cancer.

Transforming growth factor-β suppresses metastasis in a subset of human colon carcinoma cells

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Simms, Neka A K; Rajput, Ashwani; Sharratt, Elizabeth A; Ongchin, Melanie; Teggart, Carol A; Wang, Jing; Brattain, Michael G

2012-01-01

TGFβ signaling has typically been associated with suppression of tumor initiation while the role it plays in metastasis is generally associated with progression of malignancy. However, we present evidence here for an anti-metastatic role of TGFβ signaling. To test the importance of TGFβ signaling to cell survival and metastasis we compared human colon carcinoma cell lines that are either non-tumorigenic with TGFβ response (FET), or tumorigenic with TGFβ response (FETα) or tumorigenic with abrogated TGFβ response via introduction of dominant negative TGFβRII (FETα/DN) and their ability to metastasize. Metastatic competency was assessed by orthotopic transplantation. Metastatic colony formation was assessed histologically and by imaging. Abrogation of TGFβ signaling through introduction of a dominant negative TGFβ receptor II (TGFβRII) in non-metastatic FETα human colon cancer cells permits metastasis to distal organs, but importantly does not reduce invasive behavior at the primary site. Loss of TGFβ signaling in FETα-DN cells generated enhanced cell survival capabilities in response to cellular stress in vitro. We show that enhanced cellular survival is associated with increased AKT phosphorylation and cytoplasmic expression of inhibitor of apoptosis (IAP) family members (survivin and XIAP) that elicit a cytoprotective effect through inhibition of caspases in response to stress. To confirm that TGFβ signaling is a metastasis suppressor, we rescued TGFβ signaling in CBS metastatic colon cancer cells that had lost TGFβ receptor expression due to epigenetic repression. Restoration of TGFβ signaling resulted in the inhibition of metastatic colony formation in distal organs by these cells. These results indicate that TGFβ signaling has an important role in the suppression of metastatic potential in tumors that have already progressed to the stage of an invasive carcinoma. The observations presented here indicate a metastasis suppressor role for TGF�

Antiproliferative Activity of Egg Yolk Peptides in Human Colon Cancer Cells.

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Yousr, Marwa N; Aloqbi, Akram A; Omar, Ulfat M; Howell, Nazlin K

2017-01-01

Egg yolk peptides were successfully prepared from egg yolk protein by-products after lecithin extraction. Defatted egg yolk protein was hydrolyzed with pepsin and pancreatin and purified by gel filtration to produce egg yolk gel filtration fraction (EYGF-33) with antiproliferative activity. The highlight of this study was that the peptide EYGF-33 (1.0 mg/ml) significantly inhibits cell viability of colon cancer cells (Caco-2) with no inhibitory effects on the viability of human colon epithelial normal cells (HCEC) after 48 h. Reduced cell viability can be explained by cell cycle arrest in the S-phase in which DNA replication normally takes place. EYGF-33 significantly enhanced the production of superoxide anions in the mitochondria of Caco-2 cells; this could activate a mitochondrial apoptotic pathway leading to typical Poly Adenosine diphosphate-ribose polymerase (PARP) cleavage as observed in the Western blot result. The induction of apoptotic cell death by EYGF-33 was supported by the externalization of phosphatidylserine (PS). However, further elucidation of the mechanism of EYGF-33-mediated apoptosis would provide further support for its use as a potential therapeutic and chemopreventive agent.

Pathway of deoxynivalenol-induced apoptosis in human colon carcinoma cells

International Nuclear Information System (INIS)

Bensassi, Fatma; El Golli-Bennour, Emna; Abid-Essefi, Salwa; Bouaziz, Chayma; Hajlaoui, Mohamed Rabeh; Bacha, Hassen

2009-01-01

The mycotoxin, deoxynivalenol (DON), is generally detected in cereal grains and grain-based food products worldwide. Therefore, DON has numerous toxicological effects on animals and humans. The present investigation was conducted to determine the molecular aspects of DON toxicity on human colon carcinoma cells (HT 29). To this aim, we have monitored the effects of DON on (i) cell viability, (ii) Heat shock protein expressions as a parameter of protective and adaptive response, (iii) oxidative damage and (iv) cell death signalling pathway. Our results clearly showed that DON treatment inhibits cell proliferation, did not induce Hsp 70 protein expression and reactive oxygen species generation. We have also demonstrated that this toxin induced a DNA fragmentation followed by p53 and caspase-3 activations. Finally, our findings suggested that oxidative damage is not the major contributor to DON toxicity. This mycotoxin induces direct DNA lesions and could be considered by this fact as a genotoxic agent inducing cell death via an apoptotic process.

Proteomic profiling of human colon cancer cells treated with the histone deacetylase inhibitor belinostat

DEFF Research Database (Denmark)

Beck, Hans Christian; Petersen, Jørgen; Nielsen, Søren Jensby

2010-01-01

in the human colon cancer cell line HCT116. Protein extracts from untreated HCT116 cells, and cells grown for 24 h in the presence of 1 and 10 muM belinostat were analysed by 2-D gel electrophoresis. Proteins were visualized by colloidal Coomassie blue staining and quantitative analysis of gel images revealed...

Plaque assay for human coronavirus NL63 using human colon carcinoma cells

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Drosten Christian

2008-11-01

Full Text Available Abstract Background Coronaviruses cause a broad range of diseases in animals and humans. Human coronavirus (hCoV NL63 is associated with up to 10% of common colds. Viral plaque assays enable the characterization of virus infectivity and allow for purifying virus stock solutions. They are essential for drug screening. Hitherto used cell cultures for hCoV-NL63 show low levels of virus replication and weak and diffuse cytopathogenic effects. It has not yet been possible to establish practicable plaque assays for this important human pathogen. Results 12 different cell cultures were tested for susceptibility to hCoV-NL63 infection. Human colon carcinoma cells (CaCo-2 replicated virus more than 100 fold more efficiently than commonly used African green monkey kidney cells (LLC-MK2. CaCo-2 cells showed cytopathogenic effects 4 days post infection. Avicel, agarose and carboxymethyl-cellulose overlays proved suitable for plaque assays. Best results were achieved with Avicel, which produced large and clear plaques from the 4th day of infection. The utility of plaque assays with agrose overlay was demonstrated for purifying virus, thereby increasing viral infectivity by 1 log 10 PFU/mL. Conclusion CaCo-2 cells support hCoV-NL63 better than LLC-MK2 cells and enable cytopathogenic plaque assays. Avicel overlay is favourable for plaque quantification, and agarose overlay is preferred for plaque purification. HCoV-NL63 virus stock of increased infectivity will be beneficial in antiviral screening, animal modelling of disease, and other experimental tasks.

Cell Transformation by PTP1B Truncated Mutants Found in Human Colon and Thyroid Tumors.

Science.gov (United States)

Mei, Wenhan; Wang, Kemin; Huang, Jian; Zheng, Xinmin

2016-01-01

Expression of wild-type protein tyrosine phosphatase (PTP) 1B may act either as a tumor suppressor by dysregulation of protein tyrosine kinases or a tumor promoter through Src dephosphorylation at Y527 in human breast cancer cells. To explore whether mutated PTP1B is involved in human carcinogenesis, we have sequenced PTP1B cDNAs from human tumors and found splice mutations in ~20% of colon and thyroid tumors. The PTP1BΔE6 mutant expressed in these two tumor types and another PTP1BΔE5 mutant expressed in colon tumor were studied in more detail. Although PTP1BΔE6 revealed no phosphatase activity compared with wild-type PTP1B and the PTP1BΔE5 mutant, its expression induced oncogenic transformation of rat fibroblasts without Src activation, indicating that it involved signaling pathways independent of Src. The transformed cells were tumourigenic in nude mice, suggesting that the PTP1BΔE6 affected other molecule(s) in the human tumors. These observations may provide a novel therapeutic target for colon and thyroid cancer.

PKH26 staining defines distinct subsets of normal human colon epithelial cells at different maturation stages.

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Anna Pastò

Full Text Available BACKGROUND AND AIM: Colon crypts are characterized by a hierarchy of cells distributed along the crypt axis. Aim of this paper was to develop an in vitro system for separation of epithelial cell subsets in different maturation stages from normal human colon. METHODOLOGY AND MAJOR FINDINGS: Dissociated colonic epithelial cells were stained with PKH26, which allows identification of distinct populations based on their proliferation rate, and cultured in vitro in the absence of serum. The cytofluorimetric expression of CK20, Msi-1 and Lgr5 was studied. The mRNA levels of several stemness-associated genes were also compared in cultured cell populations and in three colon crypt populations isolated by microdissection. A PKH(pos population survived in culture and formed spheroids; this population included subsets with slow (PKH(high and rapid (PKH(low replicative rates. Molecular analysis revealed higher mRNA levels of both Msi-1 and Lgr-5 in PKH(high cells; by cytofluorimetric analysis, Msi-1(+/Lgr5(+ cells were only found within PKH(high cells, whereas Msi-1(+/Lgr5(- cells were also observed in the PKH(low population. As judged by qRT-PCR analysis, the expression of several stemness-associated markers (Bmi-1, EphB2, EpCAM, ALDH1 was highly enriched in Msi-1(+/Lgr5(+ cells. While CK20 expression was mainly found in PKH(low and PKH(neg cells, a small PKH(high subset co-expressed both CK20 and Msi-1, but not Lgr5; cells with these properties also expressed Mucin, and could be identified in vivo in colon crypts. These results mirrored those found in cells isolated from different crypt portions by microdissection, and based on proliferation rates and marker expression they allowed to define several subsets at different maturation stages: PKH(high/Lgr5(+/Msi-1(+/CK20(-, PKH(high/Lgr5(-/Msi-1(+/CK20(+, PKH(low/Lgr5(-/Msi-1(+/Ck20(-, and PKH(low/Lgr5(-/Msi-1(-/CK20(+ cells. CONCLUSIONS: Our data show the possibility of deriving in vitro, without any

Compartment-specific immunity in the human gut: properties and functions of dendritic cells in the colon versus the ileum.

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Mann, Elizabeth R; Bernardo, David; English, Nicholas R; Landy, Jon; Al-Hassi, Hafid O; Peake, Simon T C; Man, Ripple; Elliott, Timothy R; Spranger, Henning; Lee, Gui Han; Parian, Alyssa; Brant, Steven R; Lazarev, Mark; Hart, Ailsa L; Li, Xuhang; Knight, Stella C

2016-02-01

Dendritic cells (DC) mediate intestinal immune tolerance. Despite striking differences between the colon and the ileum both in function and bacterial load, few studies distinguish between properties of immune cells in these compartments. Furthermore, information of gut DC in humans is scarce. We aimed to characterise human colonic versus ileal DC. Human DC from paired colonic and ileal samples were characterised by flow cytometry, electron microscopy or used to stimulate T cell responses in a mixed leucocyte reaction. A lower proportion of colonic DC produced pro-inflammatory cytokines (tumour necrosis factor-α and interleukin (IL)-1β) compared with their ileal counterparts and exhibited an enhanced ability to generate CD4(+)FoxP3(+)IL-10(+) (regulatory) T cells. There were enhanced proportions of CD103(+)Sirpα(-) DC in the colon, with increased proportions of CD103(+)Sirpα(+) DC in the ileum. A greater proportion of colonic DC subsets analysed expressed the lymph-node-homing marker CCR7, alongside enhanced endocytic capacity, which was most striking in CD103(+)Sirpα(+) DC. Expression of the inhibitory receptor ILT3 was enhanced on colonic DC. Interestingly, endocytic capacity was associated with CD103(+) DC, in particular CD103(+)Sirpα(+) DC. However, expression of ILT3 was associated with CD103(-) DC. Colonic and ileal DC differentially expressed skin-homing marker CCR4 and small-bowel-homing marker CCR9, respectively, and this corresponded to their ability to imprint these homing markers on T cells. The regulatory properties of colonic DC may represent an evolutionary adaptation to the greater bacterial load in the colon. The colon and the ileum should be regarded as separate entities, each comprising DC with distinct roles in mucosal immunity and imprinting. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Galectin-3-independent Down-regulation of GABABR1 due to Treatment with Korean Herbal Extract HAD-B Reduces Proliferation of Human Colon Cancer Cells

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Kim Kyung-Hee

2012-09-01

Full Text Available Objectives: Many efforts have shown multi-oncologic roles of galectin-3 for cell proliferation, angiogenesis, and apoptosis. However, the mechanisms by which galectin-3 is involved in cell proliferation are not yet fully understood, especially in human colon cancer cells. Methods: To cluster genes showing positively or negatively correlated expression with galectin-3, we employed human colon cancer cell lines, SNU-61, SNU-81, SNU-769B, SNU-C4 and SNU-C5 in high-throughput gene expression profiling. Gene and protein expression levels were determined by using real-time quantitative polymerase chain reaction (PCR and western blot analysis, respectively. The proliferation rate of human colon cancer cells was measured by using a 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay. Results: Expression of γ-aminobutyric acid B receptor 1 (GABABR1 showed a positive correlation with galectin-3 at both the transcriptional and the translational levels. Downregulation of galectin-3 decreased not only GABABR1 expression but also the proliferation rate of human colon cancer cells. However, Korean herbal extract, HangAmDan-B (HAD-B, decreased expression of GABABR1 without any expressional change of galectin-3, and offset γ-aminobutyric acid (GABA-enhanced human colon cancer cell proliferation. Conclusions: Our present study confirmed that GABABR1 expression was regulated by galectin-3. HAD-B induced galectin-3-independent down-regulation of GABABR1, which resulted in a decreased proliferation of human colon cancer cells. The therapeutic effect of HAD-B for the treatment of human colon cancer needs to be further validated.

Aldehyde dehydrogenase 1 is a marker for normal and malignant human colonic stem cells (SC) and tracks SC overpopulation during colon tumorigenesis.

Science.gov (United States)

Huang, Emina H; Hynes, Mark J; Zhang, Tao; Ginestier, Christophe; Dontu, Gabriela; Appelman, Henry; Fields, Jeremy Z; Wicha, Max S; Boman, Bruce M

2009-04-15

Although the concept that cancers originate from stem cells (SC) is becoming scientifically accepted, mechanisms by which SC contribute to tumor initiation and progression are largely unknown. For colorectal cancer (CRC), investigation of this problem has been hindered by a paucity of specific markers for identification and isolation of SC from normal and malignant colon. Accordingly, aldehyde dehydrogenase 1 (ALDH1) was investigated as a possible marker for identifying colonic SC and for tracking them during cancer progression. Immunostaining showed that ALDH1(+) cells are sparse and limited to the normal crypt bottom, where SCs reside. During progression from normal epithelium to mutant (APC) epithelium to adenoma, ALDH1(+) cells increased in number and became distributed farther up the crypt. CD133(+) and CD44(+) cells, which are more numerous and broadly distributed in normal crypts, showed similar changes during tumorigenesis. Flow cytometric isolation of cancer cells based on enzymatic activity of ALDH (Aldefluor assay) and implantation of these cells in nonobese diabetic-severe combined immunodeficient mice (a) generated xenograft tumors (Aldefluor(-) cells did not), (b) generated them after implanting as few as 25 cells, and (c) generated them dose dependently. Further isolation of cancer cells using a second marker (CD44(+) or CD133(+) serially) only modestly increased enrichment based on tumor-initiating ability. Thus, ALDH1 seems to be a specific marker for identifying, isolating, and tracking human colonic SC during CRC development. These findings also support our original hypothesis, derived previously from mathematical modeling of crypt dynamics, that progressive colonic SC overpopulation occurs during colon tumorigenesis and drives CRC development.

Liver X receptor ligand cytotoxicity in colon cancer cells and not in normal colon epithelial cells depends on LXRβ subcellular localization.

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Courtaut, Flavie; Derangère, Valentin; Chevriaux, Angélique; Ladoire, Sylvain; Cotte, Alexia K; Arnould, Laurent; Boidot, Romain; Rialland, Mickaël; Ghiringhelli, François; Rébé, Cédric

2015-09-29

Increasing evidence indicates that Liver X Receptors (LXRs) have some anticancer properties. We recently demonstrated that LXR ligands induce colon cancer cell pyroptosis through an LXRβ-dependent pathway. In the present study, we showed that human colon cancer cell lines presented differential cytoplasmic localizations of LXRβ. This localization correlated with caspase-1 activation and cell death induction under treatment with LXR ligand. The association of LXRβ with the truncated form of RXRα (t-RXRα) was responsible for the sequestration of LXRβ in the cytoplasm in colon cancer cells. Moreover t-RXRα was not expressed in normal colon epithelial cells. These cells presented a predominantly nuclear localization of LXRβ and were resistant to LXR ligand cytotoxicity. Our results showed that predominant cytoplasmic localization of LXRβ, which occurs in colon cancer cells but not in normal colon epithelial cells, allowed LXR ligand-induced pyroptosis. This study strengthens the hypothesis that LXRβ could be a promising target in cancer therapy.

Assessment of cytotoxicity of Portulaca oleracea Linn. against human colon adenocarcinoma and vero cell line

Science.gov (United States)

Mali, Prashant Y.

2015-01-01

Background: Portulaca oleracea Linn. (Portulacaceae) is commonly known as purslane in English. In traditional system it is used to cure diarrhea, dysentery, leprosy, ulcers, asthma, and piles, reduce small tumors and inflammations. Aim: To assess cytotoxic potential of chloroform extract of P. oleracea whole plant against human colon adenocarcinoma (HCT-15) and normal (Vero) cell line. Materials and Methods: Characterization of chloroform extract of P. oleracea by Fourier transform infrared (FTIR) spectroscopy was performed. Cytotoxicity (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was used for assessment of cytotoxic potential of chloroform extract of P. oleracea. The concentrations of 1000–0.05 μg/ml were used in the experiment. Doxorubicin was considered as standard reference drug. Results: FTIR spectrum showed the peak at 1019.52 and 1396.21 center. The 50% cell growth inhibition (IC50) of chloroform extract of P. oleracea and doxorubicin was 1132.02 μg/ml and 460.13 μg/ml against human colon adenocarcinoma and 767.60 μg/ml and 2392.71 μg/ml against Vero cell line, respectively. Conclusion: Chloroform extract of P. oleracea whole plant was less efficient or does not have cytotoxic activity against human colon adenocarcinoma cell line. It was not safe to normal Vero cell line. But, there is a need to isolate, identify, and confirm the phytoconstituents present in extract by sophisticated analytical techniques. PMID:27833374

STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH{sup +}/CD133{sup +} stem cell-like human colon cancer cells

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Lin, Li, E-mail: lin.796@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China); Fuchs, James; Li, Chenglong [Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 (United States); Olson, Veronica [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Bekaii-Saab, Tanios [Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States); Lin, Jiayuh, E-mail: lin.674@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States)

2011-12-16

Highlights: Black-Right-Pointing-Pointer The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. Black-Right-Pointing-Pointer STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. Black-Right-Pointing-Pointer Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. Black-Right-Pointing-Pointer STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. Black-Right-Pointing-Pointer Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH{sup +}/CD133{sup +}). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower

Noscapine induces mitochondria-mediated apoptosis in human colon cancer cells in vivo and in vitro

International Nuclear Information System (INIS)

Yang, Zi-Rong; Liu, Meng; Peng, Xiu-Lan; Lei, Xiao-Fei; Zhang, Ji-Xiang; Dong, Wei-Guo

2012-01-01

Highlights: ► Noscapine inhibited cell viability of colon cancer in a time- and dose- dependent manner. ► G 2 /M phase arrest and chromatin condensation and nuclear fragmentation were induced. ► Noscapine promoted apoptosis via mitochondrial pathways. ► Tumorigenicity was inhibited by noscapine. -- Abstract: Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC 50 = 75 μM). This cytotoxicity was reflected by cell cycle arrest at G 2 /M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer.

Dysfunctions at human intestinal barrier by water-borne protozoan parasites: lessons from cultured human fully differentiated colon cancer cell lines.

Science.gov (United States)

Liévin-Le Moal, Vanessa

2013-06-01

Some water-borne protozoan parasites induce diseases through their membrane-associated functional structures and virulence factors that hijack the host cellular molecules and signalling pathways leading to structural and functional lesions in the intestinal barrier. In this Microreview we analyse the insights on the mechanisms of pathogenesis of Entamoeba intestinalis, Giardia and Cryptosporidium observed in the human colon carcinoma fully differentiated colon cancer cell lines, cell subpopulations and clones expressing the structural and functional characteristics of highly specialized fully differentiated epithelial cells lining the intestinal epithelium and mimicking structurally and functionally an intestinal barrier. © 2013 John Wiley & Sons Ltd.

MicroRNAs Induce Epigenetic Reprogramming and Suppress Malignant Phenotypes of Human Colon Cancer Cells.

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Hisataka Ogawa

Full Text Available Although cancer is a genetic disease, epigenetic alterations are involved in its initiation and progression. Previous studies have shown that reprogramming of colon cancer cells using Oct3/4, Sox2, Klf4, and cMyc reduces cancer malignancy. Therefore, cancer reprogramming may be a useful treatment for chemo- or radiotherapy-resistant cancer cells. It was also reported that the introduction of endogenous small-sized, non-coding ribonucleotides such as microRNA (miR 302s and miR-369-3p or -5p resulted in the induction of cellular reprogramming. miRs are smaller than the genes of transcription factors, making them possibly suitable for use in clinical strategies. Therefore, we reprogrammed colon cancer cells using miR-302s and miR-369-3p or -5p. This resulted in inhibition of cell proliferation and invasion and the stimulation of the mesenchymal-to-epithelial transition phenotype in colon cancer cells. Importantly, the introduction of the ribonucleotides resulted in epigenetic reprogramming of DNA demethylation and histone modification events. Furthermore, in vivo administration of the ribonucleotides in mice elicited the induction of cancer cell apoptosis, which involves the mitochondrial Bcl2 protein family. The present study shows that the introduction of miR-302s and miR-369s could induce cellular reprogramming and modulate malignant phenotypes of human colorectal cancer, suggesting that the appropriate delivery of functional small-sized ribonucleotides may open a new avenue for therapy against human malignant tumors.

Noscapine induces mitochondria-mediated apoptosis in human colon cancer cells in vivo and in vitro

Energy Technology Data Exchange (ETDEWEB)

Yang, Zi-Rong; Liu, Meng; Peng, Xiu-Lan; Lei, Xiao-Fei; Zhang, Ji-Xiang [Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province (China); Dong, Wei-Guo, E-mail: dongwg1966@yahoo.com.cn [Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province (China)

2012-05-11

Highlights: Black-Right-Pointing-Pointer Noscapine inhibited cell viability of colon cancer in a time- and dose- dependent manner. Black-Right-Pointing-Pointer G{sub 2}/M phase arrest and chromatin condensation and nuclear fragmentation were induced. Black-Right-Pointing-Pointer Noscapine promoted apoptosis via mitochondrial pathways. Black-Right-Pointing-Pointer Tumorigenicity was inhibited by noscapine. -- Abstract: Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC{sub 50} = 75 {mu}M). This cytotoxicity was reflected by cell cycle arrest at G{sub 2}/M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer.

MSH3-deficiency initiates EMAST without oncogenic transformation of human colon epithelial cells.

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Christoph Campregher

Full Text Available BACKGROUND/AIM: Elevated microsatellite instability at selected tetranucleotide repeats (EMAST is a genetic signature in certain cases of sporadic colorectal cancer and has been linked to MSH3-deficiency. It is currently controversial whether EMAST is associated with oncogenic properties in humans, specifically as cancer development in Msh3-deficient mice is not enhanced. However, a mutator phenotype is different between species as the genetic positions of repetitive sequences are not conserved. Here we studied the molecular effects of human MSH3-deficiency. METHODS: HCT116 and HCT116+chr3 (both MSH3-deficient and primary human colon epithelial cells (HCEC, MSH3-wildtype were stably transfected with an EGFP-based reporter plasmid for the detection of frameshift mutations within an [AAAG]17 repeat. MSH3 was silenced by shRNA and changes in protein expression were analyzed by shotgun proteomics. Colony forming assay was used to determine oncogenic transformation and double strand breaks (DSBs were assessed by Comet assay. RESULTS: Despite differential MLH1 expression, both HCT116 and HCT116+chr3 cells displayed comparable high mutation rates (about 4×10(-4 at [AAAG]17 repeats. Silencing of MSH3 in HCECs leads to a remarkable increased frameshift mutations in [AAAG]17 repeats whereas [CA]13 repeats were less affected. Upon MSH3-silencing, significant changes in the expression of 202 proteins were detected. Pathway analysis revealed overexpression of proteins involved in double strand break repair (MRE11 and RAD50, apoptosis, L1 recycling, and repression of proteins involved in metabolism, tRNA aminoacylation, and gene expression. MSH3-silencing did not induce oncogenic transformation and DSBs increased 2-fold. CONCLUSIONS: MSH3-deficiency in human colon epithelial cells results in EMAST, formation of DSBs and significant changes of the proteome but lacks oncogenic transformation. Thus, MSH3-deficiency alone is unlikely to drive human colon

Prevention and treatment of colon cancer by peroral administration of HAMLET (human α-lactalbumin made lethal to tumour cells).

Science.gov (United States)

Puthia, Manoj; Storm, Petter; Nadeem, Aftab; Hsiung, Sabrina; Svanborg, Catharina

2014-01-01

Most colon cancers start with dysregulated Wnt/β-catenin signalling and remain a major therapeutic challenge. Examining whether HAMLET (human α-lactalbumin made lethal to tumour cells) may be used for colon cancer treatment is logical, based on the properties of the complex and its biological context. To investigate if HAMLET can be used for colon cancer treatment and prevention. Apc(Min)(/+) mice, which carry mutations relevant to hereditary and sporadic human colorectal tumours, were used as a model for human disease. HAMLET was given perorally in therapeutic and prophylactic regimens. Tumour burden and animal survival of HAMLET-treated and sham-fed mice were compared. Tissue analysis focused on Wnt/β-catenin signalling, proliferation markers and gene expression, using microarrays, immunoblotting, immunohistochemistry and ELISA. Confocal microscopy, reporter assay, immunoprecipitation, immunoblotting, ion flux assays and holographic imaging were used to determine effects on colon cancer cells. Peroral HAMLET administration reduced tumour progression and mortality in Apc(Min)(/+) mice. HAMLET accumulated specifically in tumour tissue, reduced β-catenin and related tumour markers. Gene expression analysis detected inhibition of Wnt signalling and a shift to a more differentiated phenotype. In colon cancer cells with APC mutations, HAMLET altered β-catenin integrity and localisation through an ion channel-dependent pathway, defining a new mechanism for controlling β-catenin signalling. Remarkably, supplying HAMLET to the drinking water from the time of weaning also significantly prevented tumour development. These data identify HAMLET as a new, peroral agent for colon cancer prevention and treatment, especially needed in people carrying APC mutations, where colon cancer remains a leading cause of death.

Superoxide production and expression of NAD(P)H oxidases by transformed and primary human colonic epithelial cells

DEFF Research Database (Denmark)

Perner, A; Andresen, Lars; Pedersen, G

2003-01-01

Superoxide (O(2)(-)) generation through the activity of reduced nicotinamide dinucleotide (NADH) or reduced nicotinamide dinucleotide phosphate (NADPH) oxidases has been demonstrated in a variety of cell types, but not in human colonic epithelial cells....

Pro-apoptotic and anti-proliferative effects of corn silk extract on human colon cancer cell lines

OpenAIRE

Guo, Hao; Guan, Hong; Yang, Wenqin; Liu, Han; Hou, Huiling; Chen, Xue; Liu, Zhenyan; Zang, Chuangang; Liu, Yuchao; Liu, Jicheng

2016-01-01

Corn silk is an economically and nutritionally significant natural product as it represents a staple food for a large proportion of the world population. This study investigated the anticancer activity of corn silk extract in human colon cancer cells and human gastric cancer cells. Following treatment with corn silk extract, certain apoptosis-related events were observed, including inhibition of cell proliferation, loss of mitochondrial membrane potential (??m), release of Ca2+ and release of...

5-Fluorouracil-radiation interactions in human colon adenocarcinoma cells

International Nuclear Information System (INIS)

Buchholz, Daniel J.; Lepek, Katherine J.; Rich, Tyvin A.; Murray, David

1995-01-01

Purpose: To determine the effect of cellular proliferation and cell cycle stage on the ability of postirradiation 5-fluorouracil (5-FU) to radiosensitize cultured human colon adenocarcinoma Clone A cells. Methods and Materials: Cell survival curves were generated for irradiated: (a) log- and plateau-phase Clone A cells; and (b) Clone A cells separated by centrifugal elutriation into the various phases of the cell cycle; with and without postirradiation treatment with 100 μg/ml 5-FU. Results: Postirradiation treatment with 5-FU sensitized proliferating cells to a greater degree than it sensitized cells growing in plateau phase. The β component of cell kill in log-phase cells was increased by a factor of 1.5 with a sensitizer enhancement ratio of 1.21 at the 0.01 survival level. Plateau-phase cells showed less radiosensitization (sensitizer enhancement ratio of 1.13 at the 0.01 survival level); however, there was a mild increase in both α and β kill in plateau-phase cells. Elutriated G 1 cells were the most radiosensitive, independent of treatment with 5-FU. The phase of the cell cycle had little effect on the ability of fluorouracil to radiosensitize Clone A cells. Conclusion: Proliferating cells are more susceptible to radiosensitization with 5-FU than plateau-phase cells are, but this effect appears to be independent of the phase of the cell cycle

Colon cancer associated transcripts in human cancers.

Science.gov (United States)

Chen, Yincong; Xie, Haibiao; Gao, Qunjun; Zhan, Hengji; Xiao, Huizhong; Zou, Yifan; Zhang, Fuyou; Liu, Yuchen; Li, Jianfa

2017-10-01

Long non-coding RNAs serve as important regulators in complicated cellular activities, including cell differentiation, proliferation and death. Dysregulation of long non-coding RNAs occurs in the formation and progression of cancers. The family of colon cancer associated transcripts, long non-coding RNAs colon cancer associated transcript-1 and colon cancer associated transcript-2 are known as oncogenes involved in various cancers. Colon cancer associated transcript-1 is a novel lncRNA located in 8q24.2, and colon cancer associated transcript-2 maps to the 8q24.21 region encompassing rs6983267. Colon cancer associated transcripts have close associations with clinical characteristics, such as lymph node metastasis, high TNM stage and short overall survival. Knockdown of them can reverse the malignant phenotypes of cancer cells, including proliferation, migration, invasion and apoptosis. Moreover, they can increase the expression level of c-MYC and oncogenic microRNAs via activating a series of complex mechanisms. In brief, the family of colon cancer associated transcripts may serve as potential biomarkers or therapeutic targets for human cancers. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells.

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Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

2016-01-01

Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer.

Curcumin inhibits growth potential by G1 cell cycle arrest and induces apoptosis in p53-mutated COLO 320DM human colon adenocarcinoma cells.

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Dasiram, Jade Dhananjay; Ganesan, Ramamoorthi; Kannan, Janani; Kotteeswaran, Venkatesan; Sivalingam, Nageswaran

2017-02-01

Curcumin, a natural polyphenolic compound and it is isolated from the rhizome of Curcuma longa, have been reported to possess anticancer effect against stage I and II colon cancer. However, the effect of curcumin on colon cancer at Dukes' type C metastatic stage III remains still unclear. In the present study, we have investigated the anticancer effects of curcumin on p53 mutated COLO 320DM human colon adenocarcinoma cells derived from Dukes' type C metastatic stage. The cellular viability and proliferation were assessed by trypan blue exclusion assay and MTT assay, respectively. The cytotoxicity effect was examined by lactate dehydrogenase (LDH) cytotoxicity assay. Apoptosis was analyzed by DNA fragmentation analysis, Hoechst and propidium iodide double fluorescent staining and confocal microscopy analysis. Cell cycle distribution was performed by flow cytometry analysis. Here we have observed that curcumin treatment significantly inhibited the cellular viability and proliferation potential of p53 mutated COLO 320DM cells in a dose- and time-dependent manner. In addition, curcumin treatment showed no cytotoxic effects to the COLO 320DM cells. DNA fragmentation analysis, Hoechst and propidium iodide double fluorescent staining and confocal microscopy analysis revealed that curcumin treatment induced apoptosis in COLO 320DM cells. Furthermore, curcumin caused cell cycle arrest at the G1 phase, decreased the cell population in the S phase and induced apoptosis in COLO 320DM colon adenocarcinoma cells. Together, these data suggest that curcumin exerts anticancer effects and induces apoptosis in p53 mutated COLO 320DM human colon adenocarcinoma cells derived from Dukes' type C metastatic stage. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Methanolic extracts of Uncaria rhynchophylla induce cytotoxicity and apoptosis in HT-29 human colon carcinoma cells.

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Jo, Kyung-Jin; Cha, Mi-Ran; Lee, Mi-Ra; Yoon, Mi-Young; Park, Hae-Ryong

2008-06-01

In this paper, we report the anticancer activities of Uncaria rhynchophylla extracts, a Rubiaceae plant native to China. Traditionally, Uncaria rhynchophylla has been used in the prevention and treatment of neurotoxicity. However, the cytotoxic activity of Uncaria rhynchophylla against human colon carcinoma cells has not, until now, been elucidated. We found that the methanolic extract of Uncaria rhynchophylla (URE) have cytotoxic effects on HT-29 cells. The URE showed highly cytotoxic effects via the MTT reduction assay, LDH release assay, and colony formation assay. As expected, URE inhibited the growth of HT-29 cells in a dose-dependent manner. In particular, the methanolic URE of the 500 microg/ml showed 15.8% inhibition against growth of HT-29 cells. It induced characteristic apoptotic effects in HT-29 cells, including chromatin condensation and sharking occurring 24 h when the cells were treated at a concentration of the 500 microg/ml. The activation of caspase-3 and the specific proteolytic cleavage of poly (ADP-ribose) polymerase were detected over the course of apoptosis induction. These results indicate that URE contains bioactive materials with strong activity, and is a potential chemotherapeutic agent candidate against HT-29 human colon carcinoma cells.

In vitro evaluation of antiproliferative and cytotoxic properties of pterostilbene against human colon cancer cells.

Science.gov (United States)

Wawszczyk, Joanna; Kapral, Małgorzata; Hollek, Andrzej; Węglarz, Ludmiła

2014-01-01

Colon cancer has been remaining the second leading cause of cancer mortality in Poland in the last years. Epidemiological, preclinical and clinical studies reveal that dietary phytochemicals may exert chemopreventive and therapeutic effect against colorectal cancer. There is a growing interest in identifying new biologically active agents from dietary sources in this respect. Pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene) is a naturally occurring stilbene, that has been found to have antioxidative, anti-inflammatory and antipro- liferative properties. Compared to other stilbenes, pterostilbene has greater bioavailability, and so, a greater potential for clinical applications. Recent studies showed that pterostilbene exhibits the hallmark characteristics of an anticancer agent. The aim of this study was to analyze antiproliferative and cytotoxic effects of pterostilbene on human colon cancer Caco-2 cells. They were cultured using standard techniques and exposed to increasing doses of pterostilbene (5-100 μM) for 48 and 72 h. Cell proliferation was determined by sulforhodamine B assay. The growth of treated cells was expressed as a percentage of that of untreated control cells. Pterostilbene decreased proliferation rate of Caco-2 cells in a dose- and time-dependent manner. Its concentrations = 25 μM did not affect cell growth after 48 h treatment period. Significant growth inhibition was observed in cultures incubated with higher concentrations of pterostilbene (40-100 μM). Pterostilbene at all concentrations used (5-100 μM) caused significant inhibition of cell proliferation when the experimental time period was elongated to 72 h. The maximum growth reduction was observed at 100 mM pterostilbene. The cytotoxicity of pterostilbene was evaluated in 48 h cultures based on lactate dehydrogenase (LDH) leakage into the culture medium and showed dose-related pattern. The findings of this study showed significant dose-dependent antiproliferative and cytotoxic

Histochemical and radioautographic studies of normal human fetal colon

International Nuclear Information System (INIS)

Lev, R.; Orlic, D.; New York Medical Coll., N.Y.

1974-01-01

Twenty fetal and infant colons ranging from 10 weeks in utero to 20 months postpartum, and 12 adult human colons were examined using histochemical techniques in conjunction with in vitro radioautography using Na 2 35 SO 4 as a sulfomucin precursor. Only the sulfated components of mucus in fetal goblet cells was found to differ significantly from adult colonic mucins. In the fetus sulfomucin staining was much weaker than in the adult, and was more intense in the left colon which is the reverse of the adult pattern. Sulfomucin was concentrated in the crypts throughout the fetal colon whereas in the adult right colon it predominated in the surface cells. As in the adult, saponification liberated carboxyl groups, possibly belonging to sialic acid, and vicinal hydroxyl groups from fetal mucins suggesting that this procedure hydrolyses an ester linkage between these 2 reactive groups. During the middle trimester of fetal life the colon possesses villi whose constituent cells display alkaline phosphatase in their surface coat. These and other morphological and histochemical similarities to fetal small intestine suggest that the fetal colon may have a limited capacity to absorb materials contained within swallowed amniotic fluid during this period. (orig.) [de

Identification of a developmental gene expression signature, including HOX genes, for the normal human colonic crypt stem cell niche: overexpression of the signature parallels stem cell overpopulation during colon tumorigenesis.

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Bhatlekar, Seema; Addya, Sankar; Salunek, Moreh; Orr, Christopher R; Surrey, Saul; McKenzie, Steven; Fields, Jeremy Z; Boman, Bruce M

2014-01-15

Our goal was to identify a unique gene expression signature for human colonic stem cells (SCs). Accordingly, we determined the gene expression pattern for a known SC-enriched region--the crypt bottom. Colonic crypts and isolated crypt subsections (top, middle, and bottom) were purified from fresh, normal, human, surgical specimens. We then used an innovative strategy that used two-color microarrays (∼18,500 genes) to compare gene expression in the crypt bottom with expression in the other crypt subsections (middle or top). Array results were validated by PCR and immunostaining. About 25% of genes analyzed were expressed in crypts: 88 preferentially in the bottom, 68 in the middle, and 131 in the top. Among genes upregulated in the bottom, ∼30% were classified as growth and/or developmental genes including several in the PI3 kinase pathway, a six-transmembrane protein STAMP1, and two homeobox (HOXA4, HOXD10) genes. qPCR and immunostaining validated that HOXA4 and HOXD10 are selectively expressed in the normal crypt bottom and are overexpressed in colon carcinomas (CRCs). Immunostaining showed that HOXA4 and HOXD10 are co-expressed with the SC markers CD166 and ALDH1 in cells at the normal crypt bottom, and the number of these co-expressing cells is increased in CRCs. Thus, our findings show that these two HOX genes are selectively expressed in colonic SCs and that HOX overexpression in CRCs parallels the SC overpopulation that occurs during CRC development. Our study suggests that developmental genes play key roles in the maintenance of normal SCs and crypt renewal, and contribute to the SC overpopulation that drives colon tumorigenesis.

Andrographolide suppresses proliferation of human colon cancer SW620 cells through the TLR4/NF-κB/MMP-9 signaling pathway.

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Zhang, Rui; Zhao, Jian; Xu, Jian; Jiao, De-Xin; Wang, Jian; Gong, Zhi-Qiang; Jia, Jian-Hui

2017-10-01

Modern pharmacological research has revealed that andrographolide has various functions, including anti-bacterial, anti-inflammatory and anti-viral effects, immunoregulation, treating cardiovascular and cerebrovascular diseases, and prevention and treatment of alcoholic liver injury. The present study investigated whether andrographolide suppresses the proliferation of human colon cancer cell through the Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB/matrix metalloproteinase-9 (MMP-9) signaling pathway. The MTT assay and lactate dehydrogenase assay were used to evaluate the anticancer effects of andrographolide on cell proliferation and cytotoxicity in human colon cancer SW620 cells. Flow cytometry was used to analyze the anticancer effects of andrographolide on apoptosis by Annexin V-fluorescein isothiocyanate/propidium iodide kit. The effects of andrographolide on the activity of caspase-3/9 were measured using ELISA. Western blot analysis was also used to analyze the protein expression of TLR4, myeloid differentiation primary response gene 88 (MyD88), NF-κB-p65 and MMP-9. In the present study, it was found that andrographolide suppressed the cell proliferation, augmented cytotoxicity, evoked cell apoptosis and activated caspase-3/9 activities in human colon cancer SW620 cells. The results revealed that the anti-proliferation effects of andrographolide on the SW620 cells was associated with the inhibition of TLR4, MyD88, NF-κB-p65 and MMP-9 signaling activation. The results suggest that andrographolide is a promising drug for treatment of human colon cancer via suppression of the TLR4/NF-κB/MMP-9 signaling pathway.

IL33 Promotes Colon Cancer Cell Stemness via JNK Activation and Macrophage Recruitment

Science.gov (United States)

Fang, Min; Li, Yongkui; Huang, Kai; Qi, Shanshan; Zhang, Jian; Zgodzinski, Witold; Majewski, Marek; Wallner, Grzegorz; Gozdz, Stanislaw; Macek, Pawel; Kowalik, Artur; Pasiarski, Marcin; Grywalska, Ewelina; Vatan, Linda; Nagarsheth, Nisha; Li, Wei; Zhao, Lili; Kryczek, Ilona; Wang, Guobin; Wang, Zheng; Zou, Weiping; Wang, Lin

2018-01-01

The expression and biological role of IL33 in colon cancer is poorly understood. In this study, we show that IL33 is expressed by vascular endothelial cells and tumor cells in the human colon cancer microenvironment. Administration of human IL33 and overexpression of murine IL33 enhanced human and murine colon cancer cell growth in vivo, respectively. IL33 stimulated cell sphere formation and prevented chemotherapy-induced tumor apoptosis. Mechanistically, IL33 activated core stem cell genes NANOG, NOTCH3, and OCT3/4 via the ST2 signaling pathway, and induced phosphorylation of c-Jun N terminal kinase (JNK) activation and enhanced binding of c-Jun to the promoters of the core stem cell genes. Moreover, IL33 recruited macrophages into the cancer microenvironment and stimulated them to produce prostaglandin E2, which supported colon cancer stemness and tumor growth. Clinically, tumor IL33 expression associated with poor survival in patients with metastatic colon cancer. Thus, IL33 dually targets tumor cells and macrophages and endows stem-like qualities to colon cancer cells to promote carcinogenesis. Collectively, our work reveals an immune-associated mechanism that extrinsically confers cancer cell stemness properties. Targeting the IL33 signaling pathway may offer an opportunity to treat patients with metastatic cancer. PMID:28249897

Phosphoproteomic Analysis Identifies Signaling Pathways Regulated by Curcumin in Human Colon Cancer Cells.

Science.gov (United States)

Sato, Tatsuhiro; Higuchi, Yutaka; Shibagaki, Yoshio; Hattori, Seisuke

2017-09-01

Curcumin, a major polyphenol of the spice turmeric, acts as a potent chemopreventive and chemotherapeutic agent in several cancer types, including colon cancer. Although various proteins have been shown to be affected by curcumin, how curcumin exerts its anticancer activity is not fully understood. Phosphoproteomic analyses were performed using SW480 and SW620 human colon cancer cells to identify curcumin-affected signaling pathways. Curcumin inhibited the growth of the two cell lines in a dose-dependent manner. Thirty-nine curcumin-regulated phosphoproteins were identified, five of which are involved in cancer signaling pathways. Detailed analyses revealed that the mTORC1 and p53 signaling pathways are main targets of curcumin. Our results provide insight into the molecular mechanisms of the anticancer activities of curcumin and future molecular targets for its clinical application. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells.

Science.gov (United States)

Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J

2017-09-01

Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.

Inhibition of phospholipaseD2 increases hypoxia-induced human colon cancer cell apoptosis through inactivating of the PI3K/AKT signaling pathway.

Science.gov (United States)

Liu, Maoxi; Fu, Zhongxue; Wu, Xingye; Du, Kunli; Zhang, Shouru; Zeng, Li

2016-05-01

Hypoxia is a common feature of solid tumor, and is a direct stress that triggers apoptosis in many human cell types. As one of solid cancer, hypoxia exists in the whole course of colon cancer occurrence and progression. Our previous studies shown that hypoxia induce high expression of phospholipase D2 (PLD2) and survivin in colon cancer cells. However, the correlation between PLD2 and survivin in hypoxic colon cancer cells remains unknown. In this study, we observed significantly elevated PLD2 and survivin expression levels in colon cancer tissues and cells. This is a positive correlation between of them, and co-expression of PLD2 and survivin has a positive correlation with the clinicpatholic features including tumor size, TNM stage, and lymph node metastasis. We also found that hypoxia induced the activity of PLD increased significant mainly caused by PLD2 in colon cancer cells. However, inhibition the activity of PLD2 induced by hypoxia promotes the apoptosis of human colon cancer cells, as well as decreased the expression of apoptosis markers including survivin and bcl2. Moreover, the pharmacological inhibition of PI3K/AKT supported the hypothesis that promotes the apoptosis of hypoxic colon cancer cells by PLD2 activity inhibition may through inactivation of the PI3K/AKT signaling pathway. Furthermore, interference the PLD2 gene expression leaded to the apoptosis of hypoxic colon cancer cells increased and also decreased the expression level of survivin and bcl2 may through inactivation of PI3K/AKT signaling pathway. These results indicated that PLD2 play antiapoptotic role in colon cancer under hypoxic conditions, inhibition of the activity, or interference of PLD2 gene expression will benefit for the treatment of colon cancer patients.

Characterization of the N-methoxyindole-3-carbinol (NI3C)–Induced Cell Cycle Arrest in Human Colon Cancer Cell Lines

DEFF Research Database (Denmark)

Neave, Antje S.; Sarup, Sussi; Seidelin, Michel

2005-01-01

Recent results have shown that indole-3-carbinol (I3C) inhibits the cellular growth of human cancer cell lines. In some cruciferous vegetables, another indole, N-methoxyindole-3-carbinol (NI3C), is found beside I3C. Knowledge about the biological effects of NI3C is limited. The aim of the present...... study was to show the effect of NI3C on cell growth of two human colon cancer cell lines, DLD-1 and HCT-116. For the first time it is shown that NI3C inhibits cellular growth of DLD-1 and HCT-116 and that NI3C is a more potent inhibitor of cell proliferation than I3C. In addition to the inhibition...... of cellular proliferation, NI3C caused an accumulation of HCT-116 cells in the G2/M phase, in contrast to I3C, which led to an accumulation of the colon cells in G0/G1 phase. Furthermore, NI3C delays the G1-S phase transition of synchronized HCT-116 cells. The indole-mediated cell-cycle arrest may be related...

In vitro radiosensitization by oxaliplatin and 5-fluorouracil in a human colon cancer cell line

International Nuclear Information System (INIS)

Kjellstroem, Johan; Kjellen, Elisabeth; Johnsson, Anders

2005-01-01

The current study was designed to compare the radiosensitizing effects of oxaliplatin and 5-fluorouracil (5FU) in a human colon cancer cell line. A human colon cancer cell line (S1) was treated with various doses of oxaliplatin, 5FU, radiation, and combinations thereof. Various clinically used schedules were mimicked. 5FU was either incubated during 1 h ('bolus') or 24 h ('continuous infusion'). When combining oxaliplatin and 5FU, an isobologram analysis revealed synergistic effects, regardless of 5FU schedule. The IC 10 and IC 50 -doses for the drugs where then combined with radiotherapy. With equitoxic drug doses (IC 50 ), radiosensitization was observed in the following order: oxaliplatin>5FU 24 h>5FU 1 h exposure. The degree of potentiation corresponded to approximately 0.8 Gy, 0.7 Gy, and 0.2 Gy, respectively. In this experimental setting, oxaliplatin seemed to be a better radiosensitizer than 5FU, and longer incubation time with 5FU was better than short exposure

Characterization and significance of ACE2 and Mas receptor in human colon adenocarcinoma.

Science.gov (United States)

Bernardi, Stella; Zennaro, Cristina; Palmisano, Silvia; Velkoska, Elena; Sabato, Nicoletta; Toffoli, Barbara; Giacomel, Greta; Buri, Luigi; Zanconati, Fabrizio; Bellini, Giuseppe; Burrell, Louise M; De Manzini, Nicolò; Fabris, Bruno

2012-03-01

A new arm of the renin-angiotensin system (RAS) has been recently characterized; this includes angiotensin converting enzyme (ACE)2 and angiotensin (Ang)1-7, a heptapeptide acting through the Mas receptor (MasR). Recent studies show that Ang1-7 has an antiproliferative action on lung adenocarcinoma cells. The aim of this study was to characterize RAS expression in human colon adenocarcinoma and to investigate whether Ang1-7 exerts an antiproliferative effect on human colon adenocarcinoma cells. Gene, protein expression and enzymatic activity of the main components of the RAS were determined on non-neoplastic colon mucosa as well as on the tumor mass and the mucosa taken 5 cm distant from it, both collected from patients with colon adenocarcinoma. Two different human colon cancer cell lines were treated with AngII and Ang1-7. The novel finding of this study was that MasR was significantly upregulated in colon adenocarcinoma compared with non-neoplastic colon mucosa, which showed little or no expression of it. ACE gene expression and enzymatic activity were also increased in the tumors. However, AngII and Ang1-7 did not have any pro-/antiproliferative effects in the cell lines studied. The data suggest that upregulation of the MasR could be used as a diagnostic marker of colon adenocarcinoma.

Mesenchymal Stem Cells Induce Epithelial to Mesenchymal Transition in Colon Cancer Cells through Direct Cell-to-Cell Contact

Directory of Open Access Journals (Sweden)

Hidehiko Takigawa

2017-05-01

Full Text Available We previously reported that in an orthotopic nude mouse model of human colon cancer, bone marrow–derived mesenchymal stem cells (MSCs migrated to the tumor stroma and promoted tumor growth and metastasis. Here, we evaluated the proliferation and migration ability of cancer cells cocultured with MSCs to elucidate the mechanism of interaction between cancer cells and MSCs. Proliferation and migration of cancer cells increased following direct coculture with MSCs but not following indirect coculture. Thus, we hypothesized that direct contact between cancer cells and MSCs was important. We performed a microarray analysis of gene expression in KM12SM colon cancer cells directly cocultured with MSCs. Expression of epithelial-mesenchymal transition (EMT–related genes such as fibronectin (FN, SPARC, and galectin 1 was increased by direct coculture with MSCs. We also confirmed the upregulation of these genes with real-time polymerase chain reaction. Gene expression was not elevated in cancer cells indirectly cocultured with MSCs. Among the EMT-related genes upregulated by direct coculture with MSCs, we examined the immune localization of FN, a well-known EMT marker. In coculture assay in chamber slides, expression of FN was seen only at the edges of cancer clusters where cancer cells directly contacted MSCs. FN expression in cancer cells increased at the tumor periphery and invasive edge in orthotopic nude mouse tumors and human colon cancer tissues. These results suggest that MSCs induce EMT in colon cancer cells via direct cell-to-cell contact and may play an important role in colon cancer metastasis.

Anti-proliferative effects of Bifidobacterium adolescentis SPM0212 extract on human colon cancer cell lines

International Nuclear Information System (INIS)

Lee, Do Kyung; Jang, Seok; Kim, Mi Jin; Kim, Jung Hyun; Chung, Myung Jun; Kim, Kyung Jae; Ha, Nam Joo

2008-01-01

Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of Bifidobacterium adolescentis isolated from healthy young Koreans. The anti-proliferative activity of B. adolescentis isolates was assessed by XTT assays on three human colon cancer cell lines (Caco-2, HT-29, and SW480). The effects of B. adolescentis SPM0212 butanol extract on tumor necrosis factor-α (TNF-α) and nitric oxide (NO) production were tested using the murine macrophage RAW 264.7 cell line. The butanol extract of B. adolescentis SPM0212 dose-dependently inhibited the growth of Caco-2, HT-29, and SW480 cells by 70%, 30%, and 40%, respectively, at 200 μg/mL. Additionally, the butanol extract of B. adolescentis SPM0212 induced macrophage activation and significantly increased the production of TNF-α and NO, which regulate immune modulation and are cytotoxic to tumor cells. The butanol extract of B. adolescentis SPM0212 increased activity of the host immune system and may improve human health by helping to prevent colon cancer as a biological response modifier

Differential effects of oestrogenic hormones on cell proliferation in the colonic crypt epithelium and in colonic carcinomata of rats.

Science.gov (United States)

Tutton, P J; Barkla, D H

1982-01-01

A number of hormones, including some steroids, have previously been shown to influence the rate of cell division in the colonic crypt epithelium and in colonic tumours. In this report the effect of oophorectomy and of treatment with ovarian hormones on cell proliferation in these tissues is compared. Colonic tumours cell proliferation was retarded following oophorectomy and this retardation was reversed by the administration of oestradiol, but not by the administration of progesterone. Oophorectomy did not retard cell proliferation in the colonic crypts. The possible significance of these findings in relation to age-dependent variations in the sex ratio for human bowel cancer is discussed.

Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4

NARCIS (Netherlands)

Todaro, Matilde; Alea, Mileidys Perez; Di Stefano, Anna B.; Cammareri, Patrizia; Vermeulen, Louis; Iovino, Flora; Tripodo, Claudio; Russo, Antonio; Gulotta, Gaspare; Medema, Jan Paul; Stassi, Giorgio

2007-01-01

A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The

Corticotropin-releasing hormone and mast cells in the regulation of mucosal barrier function in the human colon.

Science.gov (United States)

Wallon, Conny; Söderholm, Johan D

2009-05-01

Corticotropin-releasing hormone (CRH) is an important neuro-endocrine mediator of the stress response. Local effects of CRH in the intestinal mucosa have become evident in recent years. We showed that CRH activates CRH receptor subtypes R1 and R2 on subepithelial mast cells, thereby inducing increased transcellular uptake of protein antigens in human colonic biopsies in Ussing chambers. Ongoing studies also implicate local cholinergic signaling in regulation of macromolecular permeability in the human colon. Since increased uptake of antigenic molecules is associated with mucosal inflammation, our findings may have implications for understanding stress-related intestinal disorders.

Histamine and chondroitin sulfate E proteoglycan released by cultured human colonic mucosa: indication for possible presence of E mast cells

International Nuclear Information System (INIS)

Eliakim, R.; Gilead, L.; Ligumsky, M; Okon, E.; Rachmilewitz, D.; Razin, E.

1986-01-01

An association between the release of histamine and chondroitin sulfate E proteoglycan (PG) was demonstrates in human colonic mucosa (HCM). Colonic biopsy samples incorporated [ 35 S]sulfate into PG, which was partially released into the culture medium during the incubation period. Ascending thin-layer chromatography of the released 35 S-labeled PG after its digestion by chondroitin ABC lyase (chondroitinase, EC 4.2.2.4) followed by autoradiography yielded three products that migrated in the position of monosulfated disaccharides of N-acetylgalactosamine 4-sulfate and N-acetylgalactosoamine 6-sulfate and of an oversulfated disaccharide possessing N-acetylgalatosamine 4,6-disulfate. Cultured colonic mucosa released 23.6 +/- 3.7ng of histamine per mg of wet tissue without any special trigger. Comparison by linear regression analysis of the release of histamine and chondroitin [ 35 S]sulfate E PG revealed a correlation coefficient (r) of 0.7. Histological examination of the colonic biopsies revealed the presence of many mast cells in various degrees of degranulation in the mucosa and submucosa. The above correlation, the observation that most of the mast cells showed various degrees of degranulation, and the lack of heparin synthesis as opposed to the synthesis and immunological release of chondroitin sulfate E strongly suggest that the E mast cell exists in the human colon

Casticin induced apoptotic cell death and altered associated gene expression in human colon cancer colo 205 cells.

Science.gov (United States)

Shang, Hung-Sheng; Liu, Jia-You; Lu, Hsu-Feng; Chiang, Han-Sun; Lin, Chia-Hain; Chen, Ann; Lin, Yuh-Feng; Chung, Jing-Gung

2017-08-01

Casticin, a polymethoxyflavone, derived from natural plant Fructus Viticis exhibits biological activities including anti-cancer characteristics. The anti-cancer and alter gene expression of casticin on human colon cancer cells and the underlying mechanisms were investigated. Flow cytometric assay was used to measure viable cell, cell cycle and sub-G1 phase, reactive oxygen species (ROS) and Ca 2+ productions, level of mitochondria membrane potential (ΔΨ m ) and caspase activity. Western blotting assay was used to detect expression of protein level associated with cell death. Casticin induced cell morphological changes, decreased cell viability and induced G2/M phase arrest in colo 205 cells. Casticin increased ROS production but decreased the levels of ΔΨ m , and Ca 2+ , increased caspase-3, -8, and -9 activities. The cDNA microarray indicated that some of the cell cycle associated genes were down-regulated such as cyclin-dependent kinase inhibitor 1A (CDKN1A) (p21, Cip1) and p21 protein (Cdc42/Rac)-activated kinase 3 (PAK3). TNF receptor-associated protein 1 (TRAP1), CREB1 (cAMP responsive element binding protein 1) and cyclin-dependent kinase inhibitor 1B (CDKN1B) (p27, Kip1) genes were increased but matrix metallopeptidase 2 (MMP-2), toll-like receptor 4 (TLR4), PRKAR2B (protein kinase, cAMP-dependent, regulatory, type II, bet), and CaMK4 (calcium/calmodulin-dependent protein kinase IV) genes were inhibited. Results suggest that casticin induced cell apoptosis via the activation of the caspase- and/or mitochondria-dependent signaling cascade, the accumulation of ROS and altered associated gene expressions in colo 205 human colon cancer cells. © 2016 Wiley Periodicals, Inc.

Human Colon Tumors Express a Dominant-Negative Form of SIGIRR That Promotes Inflammation and Colitis-Associated Colon Cancer in Mice.

Science.gov (United States)

Zhao, Junjie; Bulek, Katarzyna; Gulen, Muhammet F; Zepp, Jarod A; Karagkounis, Georgio; Martin, Bradley N; Zhou, Hao; Yu, Minjia; Liu, Xiuli; Huang, Emina; Fox, Paul L; Kalady, Matthew F; Markowitz, Sanford D; Li, Xiaoxia

2015-12-01

Single immunoglobulin and toll-interleukin 1 receptor (SIGIRR), a negative regulator of the Toll-like and interleukin-1 receptor (IL-1R) signaling pathways, controls intestinal inflammation and suppresses colon tumorigenesis in mice. However, the importance of SIGIRR in human colorectal cancer development has not been determined. We investigated the role of SIGIRR in development of human colorectal cancer. We performed RNA sequence analyses of pairs of colon tumor and nontumor tissues, each collected from 68 patients. Immunoblot and immunofluorescence analyses were used to determine levels of SIGIRR protein in primary human colonic epithelial cells, tumor tissues, and colon cancer cell lines. We expressed SIGIRR and mutant forms of the protein in Vaco cell lines. We created and analyzed mice that expressed full-length (control) or a mutant form of Sigirr (encoding SIGIRR(N86/102S), which is not glycosylated) specifically in the intestinal epithelium. Some mice were given azoxymethane (AOM) and dextran sulfate sodium to induce colitis-associated cancer. Intestinal tissues were collected and analyzed by immunohistochemical and gene expression profile analyses. RNA sequence analyses revealed increased expression of a SIGIRR mRNA isoform, SIGIRR(ΔE8), in colorectal cancer tissues compared to paired nontumor tissues. SIGIRR(ΔE8) is not modified by complex glycans and is therefore retained in the cytoplasm-it cannot localize to the cell membrane or reduce IL1R signaling. SIGIRR(ΔE8) interacts with and has a dominant-negative effect on SIGIRR, reducing its glycosylation, localization to the cell surface, and function. Most SIGIRR detected in human colon cancer tissues was cytoplasmic, whereas in nontumor tissues it was found at the cell membrane. Mice that expressed SIGIRR(N86/102S) developed more inflammation and formed larger tumors after administration of azoxymethane and dextran sulfate sodium than control mice; colon tissues from these mutant mice expressed

Lebein, a snake venom disintegrin, suppresses human colon cancer cells proliferation and tumor-induced angiogenesis through cell cycle arrest, apoptosis induction and inhibition of VEGF expression.

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Zakraoui, Ons; Marcinkiewicz, Cezary; Aloui, Zohra; Othman, Houcemeddine; Grépin, Renaud; Haoues, Meriam; Essafi, Makram; Srairi-Abid, Najet; Gasmi, Ammar; Karoui, Habib; Pagès, Gilles; Essafi-Benkhadir, Khadija

2017-01-01

Lebein, is an heterodimeric disintegrin isolated from Macrovipera lebetina snake venom that was previously characterized as an inhibitor of ADP-induced platelet aggregation. In this study, we investigated the effect of Lebein on the p53-dependent growth of human colon adenocarcinoma cell lines. We found that Lebein significantly inhibited LS174 (p53wt), HCT116 (p53wt), and HT29 (p53mut) colon cancer cell viability by inducing cell cycle arrest through the modulation of expression levels of the tumor suppression factor p53, cell cycle regulating proteins cyclin D1, CDK2, CDK4, retinoblastoma (Rb), CDK1, and cyclin-dependent kinase inhibitors p21 and p27. Interestingly, Lebein-induced apoptosis of colon cancer cells was dependent on their p53 status. Thus, in LS174 cells, cell death was associated with PARP cleavage and the activation of caspases 3 and 8 while in HCT116 cells, Lebein induced caspase-independent apoptosis through increased expression of apoptosis inducing factor (AIF). In LS174 cells, Lebein triggers the activation of the MAPK ERK1/2 pathway through induction of reactive oxygen species (ROS). It also decreased cell adhesion and migration to fibronectin through down regulation of α5β1 integrin. Moreover, Lebein significantly reduced the expression of two angiogenesis stimulators, Vascular Endothelial Growth Factor (VEGF) and Neuropilin 1 (NRP1). It inhibited the VEGF-induced neovascularization process in the quail embryonic CAM system and blocked the development of human colon adenocarcinoma in nude mice. Overall, our work indicates that Lebein may be useful to design a new therapy against colon cancer. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Curcumin Conjugated with PLGA Potentiates Sustainability, Anti-Proliferative Activity and Apoptosis in Human Colon Carcinoma Cells

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Waghela, Bhargav N.; Sharma, Anupama; Dhumale, Suhashini; Pandey, Shashibahl M.; Pathak, Chandramani

2015-01-01

Curcumin, an ingredient of turmeric, exhibits a variety of biological activities such as anti-inflammatory, anti-atherosclerotic, anti-proliferative, anti-oxidant, anti-cancer and anti-metastatic. It is a highly pleiotropic molecule that inhibits cell proliferation and induces apoptosis in cancer cells. Despite its imperative biological activities, chemical instability, photo-instability and poor bioavailability limits its utilization as an effective therapeutic agent. Therefore, enhancing the bioavailability of curcumin may improve its therapeutic index for clinical setting. In the present study, we have conjugated curcumin with a biodegradable polymer Poly (D, L-lactic-co-glycolic acid) and evaluated its apoptotic potential in human colon carcinoma cells (HCT 116). The results show that curcumin-PLGA conjugate efficiently inhibits cell proliferation and cell survival in human colon carcinoma cells as compared to native curcumin. Additionally, curcumin conjugated with PLGA shows improved cellular uptake and exhibits controlled release at physiological pH as compared to native curcumin. The curcumin-PLGA conjugate efficiently activates the cascade of caspases and promotes intrinsic apoptotic signaling. Thus, the results suggest that conjugation potentiates the sustainability, anti-proliferative and apoptotic activity of curcumin. This approach could be a promising strategy to improve the therapeutic index of cancer therapy. PMID:25692854

Induction of cancer stem cell properties in colon cancer cells by defined factors.

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Nobu Oshima

Full Text Available Cancer stem cells (CSCs are considered to be responsible for the dismal prognosis of cancer patients. However, little is known about the molecular mechanisms underlying the acquisition and maintenance of CSC properties in cancer cells because of their rarity in clinical samples. We herein induced CSC properties in cancer cells using defined factors. We retrovirally introduced a set of defined factors (OCT3/4, SOX2 and KLF4 into human colon cancer cells, followed by culture with conventional serum-containing medium, not human embryonic stem cell medium. We then evaluated the CSC properties in the cells. The colon cancer cells transduced with the three factors showed significantly enhanced CSC properties in terms of the marker gene expression, sphere formation, chemoresistance and tumorigenicity. We designated the cells with CSC properties induced by the factors, a subset of the transduced cells, as induced CSCs (iCSCs. Moreover, we established a novel technology to isolate and collect the iCSCs based on the differences in the degree of the dye-effluxing activity enhancement. The xenografts derived from our iCSCs were not teratomas. Notably, in contrast to the tumors from the parental cancer cells, the iCSC-based tumors mimicked actual human colon cancer tissues in terms of their immunohistological findings, which showed colonic lineage differentiation. In addition, we confirmed that the phenotypes of our iCSCs were reproducible in serial transplantation experiments. By introducing defined factors, we generated iCSCs with lineage specificity directly from cancer cells, not via an induced pluripotent stem cell state. The novel method enables us to obtain abundant materials of CSCs that not only have enhanced tumorigenicity, but also the ability to differentiate to recapitulate a specific type of cancer tissues. Our method can be of great value to fully understand CSCs and develop new therapies targeting CSCs.

Luffa echinata Roxb. Induces Human Colon Cancer Cell (HT-29 Death by Triggering the Mitochondrial Apoptosis Pathway

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Yan Yu

2012-05-01

Full Text Available The antiproliferative properties and cell death mechanism induced by the extract of the fruits of Luffa echinata Roxb. (LER were investigated. The methanolic extract of LER inhibited the proliferation of human colon cancer cells (HT-29 in both dose-dependent and time-dependent manners and caused a significant increase in the population of apoptotic cells. In addition, obvious shrinkage and destruction of the monolayer were observed in LER-treated cells, but not in untreated cells. Analysis of the cell cycle after treatment of HT-29 cells with various concentrations indicated that LER extracts inhibited the cellular proliferation of HT-29 cells via G2/M phase arrest of the cell cycle. The Reactive oxygen species (ROS level determination revealed that LER extracts induced apoptotic cell death via ROS generation. In addition, LER treatment led to a rapid drop in mitochondrial membrane potential (MMP as a decrease in fluorescence. The transcripts of several apoptosis-related genes were investigated by RT-PCR analysis. The caspase-3 transcripts of HT-29 cells significantly accumulated and the level of Bcl-XL mRNA was decreased after treatment with LER extract. Furthermore, the ratio of mitochondria-dependent apoptosis genes (Bax and Bcl-2 was sharply increased from 1.6 to 54.1. These experiments suggest that LER has anticancer properties via inducing the apoptosis in colon cancer cells, which provided the impetus for further studies on the therapeutic potential of LER against human colon carcinoma.

CacyBP/SIP promotes the proliferation of colon cancer cells.

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Huihong Zhai

Full Text Available CacyBP/SIP is a component of the ubiquitin pathway and is overexpressed in several transformed tumor tissues, including colon cancer, which is one of the most common cancers worldwide. It is unknown whether CacyBP/SIP promotes the proliferation of colon cancer cells. This study examined the expression level, subcellular localization, and binding activity of CacyBP/SIP in human colon cancer cells in the presence and absence of the hormone gastrin. We found that CacyBP/SIP was expressed in a high percentage of colon cancer cells, but not in normal colonic surface epithelium. CacyBP/SIP promoted the cell proliferation of colon cancer cells under both basal and gastrin stimulated conditions as shown by knockdown studies. Gastrin stimulation triggered the translocation of CacyBP/SIP to the nucleus, and enhanced interaction between CacyBP/SIP and SKP1, a key component of ubiquitination pathway which further mediated the proteasome-dependent degradation of p27kip1 protein. The gastrin induced reduction in p27kip1 was prevented when cells were treated with the proteasome inhibitor MG132. These results suggest that CacyBP/SIP may be promoting growth of colon cancer cells by enhancing ubiquitin-mediated degradation of p27kip1.

CRH promotes human colon cancer cell proliferation via IL-6/JAK2/STAT3 signaling pathway and VEGF-induced tumor angiogenesis.

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Fang, Xianjun; Hong, Yali; Dai, Li; Qian, Yuanyuan; Zhu, Chao; Wu, Biao; Li, Shengnan

2017-11-01

Corticotrophin-releasing hormone (CRH) has been demonstrated to participate in various diseases. Our previous study showed that its receptor CRHR1 mediated the development of colitis-associated cancer in mouse model. However, the detailed mechanisms remain unclear. In this study, we explored the oncogenetic role of CRH/CRHR1 signaling in colon cancer cells. Cell proliferation and colony formation assays revealed that CRH contributed to cell proliferation. Moreover, tube formation assay showed that CRH-treated colon cancer cell supernatant significantly promoted tube formation of human umbilical vein endothelial cells (HUVECs). And these effects could be reversed by the CRHR1 specific antagonist Antalarmin. Further investigation showed that CRH significantly upregulated the expressions of interlukin-6 (IL-6) and vascular endothelial growth factor (VEGF) through activating nuclear factor-kappa B (NF-κB). The CRH-induced IL-6 promoted phosphorylation of janus kinase 2 (JAK2) and signal transducers and activators of transcription 3 (STAT3). STAT3 inhibition by Stattic significantly inhibited the CRH-induced cell proliferation. In addition, silence of VEGF resulted in declined tube formation induced by CRH. Taken together, CRH/CRHR1 signaling promoted human colon cancer cell proliferation via NF-κB/IL-6/JAK2/STAT3 signaling pathway and tumor angiogenesis via NF-κB/VEGF signaling pathway. Our results provide evidence to support a critical role for the CRH/CRHR1 signaling in colon cancer progression and suggest its potential utility as a new therapeutic target for colon cancer. © 2017 Wiley Periodicals, Inc.

Lactoferricin treatment decreases the rate of cell proliferation of a human colon cancer cell line.

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Freiburghaus, C; Janicke, B; Lindmark-Månsson, H; Oredsson, S M; Paulsson, M A

2009-06-01

Food components modify the risk of cancer at a large number of sites but the mechanism of action is unknown. In the present investigation, we studied the effect of the peptide lactoferricin derived from bovine milk lactoferrin on human colon cancer CaCo-2 cells. The cells were either untreated or treated with 2.0, 0.2, or 0.02 microM lactoferricin. Cell cycle kinetics were investigated with a bromodeoxyuridine DNA flow cytometric method. The results show that lactoferricin treatment slightly but significantly prolonged the S phase of the cell cycle. Lactoferricin treatment lowered the level of cyclin E1, a protein involved in the regulation of genes required for G(1)/S transition and consequently for efficient S phase progression. The slight prolongation of the S phase resulted in a reduction of cell proliferation, which became more apparent after a long treatment time.

Time- and dose-dependent effects of curcumin on gene expression in human colon cancer cells

NARCIS (Netherlands)

Erk, M.J. van; Teuling, E.; Staal, Y.C.M.; Huybers, S.; Bladeren, P.J. van; Aarts, J.M.M.J.G.; Ommen, B. van

2004-01-01

Background. Curcumin is a spice and a coloring food compound with a promising role in colon cancer prevention. Curcumin protects against development of colon tumors in rats treated with a colon carcinogen, in colon cancer cells curcumin can inhibit cell proliferation and induce apoptosis, it is an

Time- and dose-dependent effects of curcumin on gene expression in human colon cancer cells

NARCIS (Netherlands)

Erk, van M.J.; Teuling, E.; Staal, Y.C.M.; Huybers, S.; Bladeren, van P.J.; Aarts, J.M.M.J.G.; Ommen, van B.

2004-01-01

Background: Curcumin is a spice and a coloring food compound with a promising role in colon cancer prevention. Curcumin protects against development of colon tumors in rats treated with a colon carcinogen, in colon cancer cells curcumin can inhibit cell proliferation and induce apoptosis, it is an

Time- and dose-dependent effects of curcumin on gene expression in human colon cancer cells

NARCIS (Netherlands)

Van Erk, Marjan J; Teuling, Eva; Staal, Yvonne C. M.; Huybers, Sylvie; Van Bladeren, Peter J; Aarts, Jac MMJG; Van Ommen, Ben

2004-01-01

BACKGROUND: Curcumin is a spice and a coloring food compound with a promising role in colon cancer prevention. Curcumin protects against development of colon tumors in rats treated with a colon carcinogen, in colon cancer cells curcumin can inhibit cell proliferation and induce apoptosis, it is an

Long-term expansion of epithelial organoids from human colon, adenoma, adenocarcinoma, and Barrett's epithelium.

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Sato, Toshiro; Stange, Daniel E; Ferrante, Marc; Vries, Robert G J; Van Es, Johan H; Van den Brink, Stieneke; Van Houdt, Winan J; Pronk, Apollo; Van Gorp, Joost; Siersema, Peter D; Clevers, Hans

2011-11-01

We previously established long-term culture conditions under which single crypts or stem cells derived from mouse small intestine expand over long periods. The expanding crypts undergo multiple crypt fission events, simultaneously generating villus-like epithelial domains that contain all differentiated types of cells. We have adapted the culture conditions to grow similar epithelial organoids from mouse colon and human small intestine and colon. Based on the mouse small intestinal culture system, we optimized the mouse and human colon culture systems. Addition of Wnt3A to the combination of growth factors applied to mouse colon crypts allowed them to expand indefinitely. Addition of nicotinamide, along with a small molecule inhibitor of Alk and an inhibitor of p38, were required for long-term culture of human small intestine and colon tissues. The culture system also allowed growth of mouse Apc-deficient adenomas, human colorectal cancer cells, and human metaplastic epithelia from regions of Barrett's esophagus. We developed a technology that can be used to study infected, inflammatory, or neoplastic tissues from the human gastrointestinal tract. These tools might have applications in regenerative biology through ex vivo expansion of the intestinal epithelia. Studies of these cultures indicate that there is no inherent restriction in the replicative potential of adult stem cells (or a Hayflick limit) ex vivo. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

Sulforaphane Induces Cell Death Through G2/M Phase Arrest and Triggers Apoptosis in HCT 116 Human Colon Cancer Cells.

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Liu, Kuo-Ching; Shih, Ting-Ying; Kuo, Chao-Lin; Ma, Yi-Shih; Yang, Jiun-Long; Wu, Ping-Ping; Huang, Yi-Ping; Lai, Kuang-Chi; Chung, Jing-Gung

2016-01-01

Sulforaphane (SFN), an isothiocyanate, exists exclusively in cruciferous vegetables, and has been shown to possess potent antitumor and chemopreventive activity. However, there is no available information that shows SFN affecting human colon cancer HCT 116 cells. In the present study, we found that SFN induced cell morphological changes, which were photographed by contrast-phase microscopy, and decreased viability. SFN also induced G2/M phase arrest and cell apoptosis in HCT 116 cells, which were measured with flow cytometric assays. Western blotting indicated that SFN increased Cyclin A, cdk 2, Cyclin B and WEE1, but decreased Cdc 25C, cdk1 protein expressions that led to G2/M phase arrest. Apoptotic cell death was also confirmed by Annexin V/PI and DAPI staining and DNA gel electrophoresis in HCT 116 cells after exposure to SFN. The flow cytometric assay also showed that SFN induced the generation of reactive oxygen species (ROS) and Ca[Formula: see text] and decreased mitochondria membrane potential and increased caspase-8, -9 and -3 activities in HCT 116 cell. Western blotting also showed that SFN induced the release of cytochrome c, and AIF, which was confirmed by confocal microscopy examination. SFN induced ER stress-associated protein expression. Based on those observations, we suggest that SFN may be used as a novel anticancer agent for the treatment of human colon cancer in the future.

Subepithelial myofibroblasts are novel nonprofessional APCs in the human colonic mucosa.

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Saada, Jamal I; Pinchuk, Irina V; Barrera, Carlos A; Adegboyega, Patrick A; Suarez, Giovanni; Mifflin, Randy C; Di Mari, John F; Reyes, Victor E; Powell, Don W

2006-11-01

The human gastrointestinal mucosa is exposed to a diverse normal microflora and dietary Ags and is a common site of entry for pathogens. The mucosal immune system must respond to these diverse signals with either the initiation of immunity or tolerance. APCs are important accessory cells that modulate T cell responses which initiate and maintain adaptive immunity. The ability of APCs to communicate with CD4+ T cells is largely dependent on the expression of class II MHC molecules by the APCs. Using immunohistochemistry, confocal microscopy, and flow cytometry, we demonstrate that alpha-smooth muscle actin(+), CD90+ subepithelial myofibroblasts (stromal cells) constitutively express class II MHC molecules in normal colonic mucosa and that they are distinct from professional APCs such as macrophages and dendritic cells. Primary isolates of human colonic myofibroblasts (CMFs) cultured in vitro were able to stimulate allogeneic CD4+ T cell proliferation. This process was dependent on class II MHC and CD80/86 costimulatory molecule expression by the myofibroblasts. We also demonstrate that CMFs, engineered to express a specific DR4 allele, can process and present human serum albumin to a human serum albumin-specific and DR4 allele-restricted T cell hybridoma. These studies characterize a novel cell phenotype which, due to its strategic location and class II MHC expression, may be involved in capture of Ags that cross the epithelial barrier and present them to lamina propria CD4+ T cells. Thus, human CMFs may be important in regulating local immunity in the colon.

Modulation of Human Serotonin Transporter Expression by 5-HTTLPR in Colon Cells

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Tewin Tencomnao

2011-10-01

Full Text Available Serotonin (5-HT is a monoamine neurotransmitter and plays important roles in several of the human body’s systems. Known as a primary target for psychoactive drug development, the 5-HT transporter (5-HTT, SERT plays a critical role in the regulation of serotonergic function by reuptaking 5-HT. The allelic variation of 5-HTT expression is caused by functional gene promoter polymorphism with two principal variant alleles, 5-HTT gene-linked polymorphic region (5-HTTLPR. It has been demonstrated that 5-HTTLPR is associated with numerous neuropsychiatric disorders. The functional roles of 5-HTTLPR have been reported in human choriocarcinoma (JAR, lymphoblast and raphe cells. To date, the significance of 5-HTTLPR in gastrointestinal tract-derived cells has never been elucidated. Thus, the impact of 5-HTTLPR on 5-HTT transcription was studied in SW480 human colon carcinoma cells, which were shown to express 5-HTT. We found 42-bp fragment in long (L allele as compared to short (S allele, and this allelic difference resulted in 2-fold higher transcriptional efficiency of L allele (P < 0.05 as demonstrated using a functional reporter gene assay. Nevertheless, the transcriptional effect of estrogen and glucocorticoid on 5-HTT expression via 5-HTTLPR was not found in this cell line. Our study was the first to demonstrate the molecular role of this allelic variation in gastrointestinal tract cells.

Enteric Neural Cells From Hirschsprung Disease Patients Form Ganglia in Autologous Aneuronal ColonSummary

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Benjamin N. Rollo

2016-01-01

Full Text Available Background & Aims: Hirschsprung disease (HSCR is caused by failure of cells derived from the neural crest (NC to colonize the distal bowel in early embryogenesis, resulting in absence of the enteric nervous system (ENS and failure of intestinal transit postnatally. Treatment is by distal bowel resection, but neural cell replacement may be an alternative. We tested whether aneuronal (aganglionic colon tissue from patients may be colonized by autologous ENS-derived cells. Methods: Cells were obtained and cryopreserved from 31 HSCR patients from the proximal resection margin of colon, and ENS cells were isolated using flow cytometry for the NC marker p75 (nine patients. Aneuronal colon tissue was obtained from the distal resection margin (23 patients. ENS cells were assessed for NC markers immunohistologically and by quantitative reverse-transcription polymerase chain reaction, and mitosis was detected by ethynyl-2′-deoxyuridine labeling. The ability of human HSCR postnatal ENS-derived cells to colonize the embryonic intestine was demonstrated by organ coculture with avian embryo gut, and the ability of human postnatal HSCR aneuronal colon muscle to support ENS formation was tested by organ coculture with embryonic mouse ENS cells. Finally, the ability of HSCR patient ENS cells to colonize autologous aneuronal colon muscle tissue was assessed. Results: ENS-derived p75-sorted cells from patients expressed multiple NC progenitor and differentiation markers and proliferated in culture under conditions simulating Wnt signaling. In organ culture, patient ENS cells migrated appropriately in aneural quail embryo gut, and mouse embryo ENS cells rapidly spread, differentiated, and extended axons in patient aneuronal colon muscle tissue. Postnatal ENS cells derived from HSCR patients colonized autologous aneuronal colon tissue in cocultures, proliferating and differentiating as neurons and glia. Conclusions: NC-lineage cells can be obtained from HSCR�

Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4.

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Todaro, Matilde; Alea, Mileidys Perez; Di Stefano, Anna B; Cammareri, Patrizia; Vermeulen, Louis; Iovino, Flora; Tripodo, Claudio; Russo, Antonio; Gulotta, Gaspare; Medema, Jan Paul; Stassi, Giorgio

2007-10-11

A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133(+) cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133(+) cells. Further analysis revealed that the CD133(+) cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, treatment with IL-4Ralpha antagonist or anti-IL-4 neutralizing antibody strongly enhances the antitumor efficacy of standard chemotherapeutic drugs through selective sensitization of CD133(+) cells. Our data suggest that colon tumor growth is dictated by stem-like cells that are treatment resistant due to the autocrine production of IL-4.

CD133+CD24lo defines a 5-Fluorouracil-resistant colon cancer stem cell-like phenotype

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Paschall, Amy V.; Yang, Dafeng; Lu, Chunwan; Redd, Priscilla S.; Choi, Jeong-Hyeon; Heaton, Christopher M.; Lee, Jeffrey R.; Nayak-Kapoor, Asha; Liu, Kebin

2016-01-01

The chemotherapeutic agent 5-Fluorouracil (5-FU) is the most commonly used drug for patients with advanced colon cancer. However, development of resistance to 5-FU is inevitable in almost all patients. The mechanism by which colon cancer develops 5-FU resistance is still unclear. One recently proposed theory is that cancer stem-like cells underlie colon cancer 5-FU resistance, but the phenotypes of 5-FU-resistant colon cancer stem cells are still controversial. We report here that 5-FU treatment selectively enriches a subset of CD133+ colon cancer cells in vitro. 5-FU chemotherapy also increases CD133+ tumor cells in human colon cancer patients. However, sorted CD133+ colon cancer cells exhibit no increased resistance to 5-FU, and CD133 levels exhibit no correlation with colon cancer patient survival or cancer recurrence. Genome-wide analysis of gene expression between sorted CD133+ colon cancer cells and 5-FU-selected colon cancer cells identifies 207 differentially expressed genes. CD24 is one of the genes whose expression level is lower in the CD133+ and 5-FU-resistant colon cancer cells as compared to CD133+ and 5-FU-sensitive colon cancer cells. Consequently, CD133+CD24lo cells exhibit decreased sensitivity to 5-FU. Therefore, we determine that CD133+CD24lo phenotype defines 5-FU-resistant human colon cancer stem cell-like cells. PMID:27659530

The dietary hydrolysable tannin punicalagin releases ellagic acid that induces apoptosis in human colon adenocarcinoma Caco-2 cells by using the mitochondrial pathway.

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Larrosa, Mar; Tomás-Barberán, Francisco A; Espín, Juan Carlos

2006-09-01

Polyphenol-rich dietary foodstuffs have attracted attention due to their cancer chemopreventive and chemotherapeutic properties. Ellagitannins (ETs) belong to the so-called hydrolysable tannins found in strawberries, raspberries, walnuts, pomegranate, oak-aged red wine, etc. Both ETs and their hydrolysis product, ellagic acid (EA), have been reported to induce apoptosis in tumour cells. Ellagitannins are not absorbed in vivo but reach the colon and release EA that is metabolised by the human microflora. Our aim was to investigate the effect of a dietary ET [pomegranate punicalagin (PUNI)] and EA on human colon cancer Caco-2 and colon normal CCD-112CoN cells. Both PUNI and EA provoked the same effects on Caco-2 cells: down-regulation of cyclins A and B1 and upregulation of cyclin E, cell-cycle arrest in S phase, induction of apoptosis via intrinsic pathway (FAS-independent, caspase 8-independent) through bcl-XL down-regulation with mitochondrial release of cytochrome c into the cytosol, activation of initiator caspase 9 and effector caspase 3. Neither EA nor PUNI induced apoptosis in normal colon CCD-112CoN cells (no chromatin condensation and no activation of caspases 3 and 9 were detected). In the case of Caco-2 cells, no specific effect can be attributed to PUNI since it was hydrolysed in the medium to yield EA, which entered into the cells and was metabolised to produce dimethyl-EA derivatives. Our study suggests that the anticarcinogenic effect of dietary ETs could be mainly due to their hydrolysis product, EA, which induced apoptosis via mitochondrial pathway in colon cancer Caco-2 cells but not in normal colon cells.

HSP90 Inhibitors, Geldanamycin and Radicicol, Enhance Fisetin-Induced Cytotoxicity via Induction of Apoptosis in Human Colonic Cancer Cells

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Ming-Shun Wu

2013-01-01

Full Text Available We revealed the cytotoxic effect of the flavonoid, fisetin (FIS, on human COLO205 colon cancer cells in the presence and absence of the HSP90 inhibitors, geldanamycin (GA and radicicol (RAD. Compared to FIS treatment alone of COLO205 cells, GA and RAD significantly enhanced FIS-induced cytotoxicity, increased expression of cleaved caspase-3 and the PAPR protein, and produced a greater density of DNA ladder formation. GA and RAD also reduced the MMPs with induction of caspase-9 protein cleavage in FIS-treated COLO205 cells. Increased caspase-3 and -9 activities were detected in COLO205 cells treated with FIS+GA or FIS+RAD, and the intensity of DNA ladder formation induced by FIS+GA was reduced by adding the caspase-3 inhibitor, DEVD-FMK. A decrease in Bcl-2 but not Bcl-XL or Bax protein by FIS+GA or FIS+RAD was identified in COLO205 cells by Western blotting. A reduction in p53 protein with increased ubiquitin-tagged proteins was observed in COLO205 cells treated with FIS+GA or FIS+RAD. Furthermore, GA and RAD reduced the stability of the p53 protein in COLO205 cells under FIS stimulation. The evidence supports HSP90 inhibitors possibly sensitizing human colon cancer cells to FIS-induced apoptosis, and treating colon cancer by combining HSP90 inhibitors with FIS deserves further in vivo study.

Combination of Quercetin and Kaempferol enhances in vitro Cytotoxicity on Human Colon Cancer (HCT-116 Cells

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Sara Jaramillo-Carmona

2014-05-01

Full Text Available Colon cancer is one of the most common types of cancer malignancy. Although flavonoids naturally occur as mixtures, little information is available regarding the additive or synergistic biochemical interactions between flavonoids. The objectives of this study were to examine the feasibility of combining two major structurally related flavonoids, quercetin and kaempferol, to affect the cell viability, cell cycle, and proliferation of the human colon cancer HCT-116 cell line. The combination of quercetin and kaempferol exhibited a greater cytotoxic efficacy than did either quercetin or kaempferol alone. This effect was highest and acted in a synergistic fashion in a 2-fold quercetin and 1-fold kaempferol IC50 combination, which also arrested cell growth in the G2/M phase and suppressed proliferation. Our observations support a structure-activity relationship based on the presence of 3’–OH moiety and/or 4’–OH moiety on the B-ring of flavonoids.

Short-Chain Fatty Acids Stimulate Angiopoietin-Like 4 Synthesis in Human Colon Adenocarcinoma Cells by Activating Peroxisome Proliferator-Activated Receptor γ

DEFF Research Database (Denmark)

Alex, Sheril; Lange, Katja; Amolo, Tom

2013-01-01

with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPARγ. Our data...

Isolation and propagation of colon cancer stem cells

NARCIS (Netherlands)

Prasetyanti, Pramudita R.; Zimberlin, Cheryl; de Sousa E Melo, Felipe; Medema, Jan Paul

2013-01-01

The design of tissue culture conditions that faithfully reproduce the characteristics of cells in their native environment remains one of the main challenges of cancer stem cell (CSC) biology. Here we describe a detailed methodology for the isolation and expansion of both human colon CSCs and mouse

Self-renewing Monolayer of Primary Colonic or Rectal Epithelial CellsSummary

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Yuli Wang

2017-07-01

Full Text Available Background & Aims: Three-dimensional organoid culture has fundamentally changed the in vitro study of intestinal biology enabling novel assays; however, its use is limited because of an inaccessible luminal compartment and challenges to data gathering in a three-dimensional hydrogel matrix. Long-lived, self-renewing 2-dimensional (2-D tissue cultured from primary colon cells has not been accomplished. Methods: The surface matrix and chemical factors that sustain 2-D mouse colonic and human rectal epithelial cell monolayers with cell repertoires comparable to that in vivo were identified. Results: The monolayers formed organoids or colonoids when placed in standard Matrigel culture. As with the colonoids, the monolayers exhibited compartmentalization of proliferative and differentiated cells, with proliferative cells located near the peripheral edges of growing monolayers and differentiated cells predominated in the central regions. Screening of 77 dietary compounds and metabolites revealed altered proliferation or differentiation of the murine colonic epithelium. When exposed to a subset of the compound library, murine organoids exhibited similar responses to that of the monolayer but with differences that were likely attributable to the inaccessible organoid lumen. The response of the human primary epithelium to a compound subset was distinct from that of both the murine primary epithelium and human tumor cells. Conclusions: This study demonstrates that a self-renewing 2-D murine and human monolayer derived from primary cells can serve as a physiologically relevant assay system for study of stem cell renewal and differentiation and for compound screening. The platform holds transformative potential for personalized and precision medicine and can be applied to emerging areas of disease modeling and microbiome studies. Keywords: Colonic Epithelial Cells, Monolayer, Organoids, Compound Screening

Colonization and infection by Helicobacter pylori in humans.

Science.gov (United States)

Andersen, Leif Percival

2007-11-01

When Helicobacter pylori arrives in the human stomach, it may penetrate the mucin layer and adhere to the gastric epithelial cells or it may pass through the stomach without colonizing the mucosa. In this paper, the colonization process and the ensuing immunological response will be briefly described. Urease production is necessary for H. pylori to establish a pH-neutral microenvironment around the bacteria. The flagella enable the bacteria to move and the shape of H. pylori makes it possible to penetrate the mucin layer where it comes into contact with the gastric epithelial cells. H. pylori contains several adhesins that enable it to adhere to the epithelial cells. This adherence activates IL-8 which, together with bacterial antigens, attracts polymorphs and monocytes and causes acute gastritis. Antigen-presenting cells activate lymphocytes and other mononuclear cells that are attracted to the inflamed mucosa, causing chronic superficial gastritis and initiating a cytotoxic or an antigen-producing Th response. The infection is established within a few weeks after the primary exposure to H. pylori. After this initial colonization, many chemical, biochemical, and immunologic reactions take place that are of importance in the progress of the infection and the development of disease.

Prehistoric human colonization of India

Indian Academy of Sciences (India)

Unknown

2. Earliest human colonization of south Asia. The early human colonization of south Asia is represented largely by an abundance of stone tool assemblages. The oldest known tools ..... component among finished tools is conspicuous in the hinterland riverine ...... sativum), green gram (Vigna radiata), gram/chicken pea.

NK-cell-dependent killing of colon carcinoma cells is mediated by natural cytotoxicity receptors (NCRs) and stimulated by parvovirus infection of target cells

International Nuclear Information System (INIS)

Bhat, Rauf; Rommelaere, Jean

2013-01-01

Investigating how the immune system functions during malignancies is crucial to developing novel therapeutic strategies. Natural killer (NK) cells, an important component of the innate immune system, play a vital role in immune defense against tumors and virus-infected cells. The poor survival rate in colon cancer makes it particularly important to develop novel therapeutic strategies. Oncolytic viruses, in addition to lysing tumor cells, may have the potential to augment antitumor immune responses. In the present study, we investigate the role of NK cells and how parvovirus H-1PV can modulate NK-cell mediated immune responses against colon carcinoma. Human NK cells were isolated from the blood of healthy donors. The cytotoxicity and antibody-mediated inhibition of NK cells were measured in chromium release assays. Phenotypic assessment of colon cancer and dendritic cells was done by FACS. The statistical significance of the results was calculated with Student’s t test (*p <0.05; **, p < 0.01; ***, p < 0.001). We show that IL-2-activated human NK cells can effectively kill colon carcinoma cells. Killing of colon carcinoma cells by NK cells was further enhanced upon infection of the former cells with parvovirus H-1PV. H-1PV has potent oncolytic activity against various tumors, yet its direct killing effect on colon carcinoma cells is limited. The cytotoxicity of NK cells towards colon carcinoma cells, both mock- and H-1PV-infected, was found to be mostly mediated by a combination of natural cytotoxicity receptors (NCRs), namely NKp30, 44, and 46. Colon carcinoma cells displayed low to moderate expression of NK cell ligands, and this expression was modulated upon H-1PV infection. Lysates of H-1PV-infected colon carcinoma cells were found to increase MHC class II expression on dendritic cells. Altogether, these data suggest that IL-2-activated NK cells actively kill colon carcinoma cells and that this killing is mediated by several natural cytotoxicity receptors

Oestrogen inhibits human colonic motility by a non-genomic cell membrane receptor-dependent mechanism.

LENUS (Irish Health Repository)

Hogan, A M

2012-02-01

BACKGROUND: Classical effects of oestrogen involve activation of target genes after binding nuclear receptors. Oestrogenic effects too rapid for DNA transcription (non-genomic) are known to occur. The effect of oestrogen on colonic motility is unknown despite the prevalence of gastrointestinal symptoms in pregnant and premenopausal women. METHODS: Histologically normal colon was obtained from proximal resection margins of colorectal carcinoma specimens. Circular smooth muscle strips were microdissected and suspended in organ baths under 1 g of tension. After equilibration, they were exposed to 17beta-oestradiol (n = 8) or bovine serum albumin (BSA)-conjugated 17beta-oestradiol (n = 8). Fulvestrant, an oestrogen receptor antagonist, was added to some baths (n = 8). Other strips were exposed to calphostin C or cycloheximide. Carbachol was added in increasing concentrations and contractile activity was recorded isometrically. RESULTS: Oestrogen inhibited colonic contractility (mean difference 19.7 per cent; n = 8, P < 0.001). In keeping with non-genomic, rapid-onset steroid action, the effect was apparent within minutes and reversible. It was observed with both 17beta-oestradiol and BSA-conjugated oestrogen, and was not altered by cycloheximide. Effects were inhibited by fulvestrant, suggesting receptor mediation. CONCLUSION: Oestrogen decreases contractility in human colonic smooth muscle by a non-genomic mechanism involving cell membrane coupling.

The Indolic Diet-Derivative, 3,3′-Diindolylmethane, Induced Apoptosis in Human Colon Cancer Cells through Upregulation of NDRG1

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A. Lerner

2012-01-01

Full Text Available N-myc downstream regulated gene-1 participates in carcinogenesis, angiogenesis, metastases, and anticancer drug resistance. In the present study, we analyzed the expression pattern of N-myc downstream regulated gene-1 following treatment of human colonic cancer cell lines; HCT-116 (well differentiated with wild-type p53 gene and Colo-320 (poorly differentiated with mutant p53 gene, with 3,3′-diindolylmethane, a well-established proapoptotic agent product derived from indole-3-carbinol. Treatment of Colo-320 and HCT-116 with 3,3′-diindolylmethane disclosed inhibition of cell viability in a dose-dependent manner, mediated through apoptosis induction. The increased expression of N-myc downstream regulated gene-1 was detected only in poorly differentiated colon cancer cells, Colo-320 cell line. Our results suggest that N-myc downstream regulated gene-1 expression is enhanced by 3,3′-diindolylmethane in poorly differentiated cells and followed by induction of apoptosis. 3,3′-diindolylmethane induced apoptosis may represent a new regulator of N-myc downstream regulated gene-1 in poorly differentiated colonic cancer cells.

Direct Measurements of Human Colon Crypt Stem Cell Niche Genetic Fidelity: The Role of Chance in Non-Darwinian Mutation Selection

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Haeyoun eKang

2013-10-01

Full Text Available Perfect human stem cell genetic fidelity would prevent aging and cancer. However, perfection would be difficult to achieve, and aging is universal and cancers common. A hypothesis is that because mutations are inevitable over a human lifetime, downstream mechanisms have evolved to manage the deleterious effects of beneficial and lethal mutations. In the colon, a crypt stem cell architecture reduces the number of mitotic cells at risk for mutation accumulation, and multiple niche stem cells ensure that a lethal mutation within any single stem cell does not lead to crypt death. In addition, the architecture of the colon crypt stem cell niche may harness probability or chance to randomly discard many beneficial mutations that might lead to cancer. An analysis of somatic chromosome copy number alterations (CNAs reveals a lack of perfect fidelity in individual normal human crypts, with age-related increases and higher frequencies in ulcerative colitis, a proliferative, inflammatory disease. The age-related increase in somatic CNAs appears consistent with relatively normal replication error and cell division rates. Surprisingly, and similar to point mutations in cancer genomes, the types of crypt mutations were more consistent with random fixation rather than selection. In theory, a simple non-Darwinian way to nullify selection is to reduce the size of the reproducing population. Fates are more determined by chance rather than selection in very small populations, and therefore selection may be minimized within small crypt niches. The desired effect is that many beneficial mutations that might lead to cancer are randomly lost by drift rather than fixed by selection. The subdivision of the colon into multiple very small stem cell niches may trade Darwinian evolution for non-Darwinian somatic cell evolution, capitulating to aging but reducing cancer risks.

Extravirgin olive oil up-regulates CB₁ tumor suppressor gene in human colon cancer cells and in rat colon via epigenetic mechanisms.

Science.gov (United States)

Di Francesco, Andrea; Falconi, Anastasia; Di Germanio, Clara; Micioni Di Bonaventura, Maria Vittoria; Costa, Antonio; Caramuta, Stefano; Del Carlo, Michele; Compagnone, Dario; Dainese, Enrico; Cifani, Carlo; Maccarrone, Mauro; D'Addario, Claudio

2015-03-01

Extravirgin olive oil (EVOO) represents the typical lipid source of the Mediterranean diet, an eating habit pattern that has been associated with a significant reduction of cancer risk. Diet is the more studied environmental factor in epigenetics, and many evidences suggest dysregulation of epigenetic pathways in cancer. The aim of our study was to investigate the effects of EVOO and its phenolic compounds on endocannabinoid system (ECS) gene expression via epigenetic regulation in both human colon cancer cells (Caco-2) and rats exposed to short- and long-term dietary EVOO. We observed a selective and transient up-regulation of CNR1 gene - encoding for type 1 cannabinoid receptor (CB₁) - that was evoked by exposure of Caco-2 cells to EVOO (100 ppm), its phenolic extracts (OPE, 50 μM) or authentic hydroxytyrosol (HT, 50 μM) for 24 h. None of the other major elements of the ECS (i.e., CB₂; GPR55 and TRPV1 receptors; and NAPE-PLD, DAGL, FAAH and MAGL enzymes) was affected at any time point. The stimulatory effect of OPE and HT on CB₁ expression was inversely correlated to DNA methylation at CNR1 promoter and was associated with reduced proliferation of Caco-2 cells. Interestingly, CNR1 gene was less expressed in Caco-2 cells when compared to normal colon mucosa cells, and again this effect was associated with higher level of DNA methylation at CNR1. Moreover, in agreement with the in vitro studies, we also observed a remarkable (~4-fold) and selective increase in CB₁ expression in the colon of rats receiving dietary EVOO supplementation for 10 days. Consistently, CpG methylation of rat Cnr1 promoter, miR23a and miR-301a, previously shown to be involved in the pathogenesis of colorectal cancer and predicted to target CB₁ mRNA, was reduced after EVOO administration down to ~50% of controls. Taken together, our findings demonstrating CB₁ gene expression modulation by EVOO or its phenolic compounds via epigenetic mechanism, both in vitro and in vivo, may

miR-320 enhances the sensitivity of human colon cancer cells to chemoradiotherapy in vitro by targeting FOXM1

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Wan, Lu-Ying; Deng, Jun; Xiang, Xiao-Jun; Zhang, Ling; Yu, Feng; Chen, Jun; Sun, Zhe; Feng, Miao; Xiong, Jian-Ping, E-mail: jpxiong@medmail.com.cn

2015-02-06

Highlights: • miR-320 plays a significant role in chemoresistance. • This role might be attribute to targeting FOXM1. • The Wnt/β-catenin pathway also involves in this chemotherapy sensitivity. - Abstract: miR-320 expression level is found to be down-regulated in human colon cancer. To date, however, its underlying mechanisms in the chemo-resistance remain largely unknown. In this study, we demonstrated that ectopic expression of miR-320 led to inhibit HCT-116 cell proliferation, invasion and hypersensitivity to 5-Fu and Oxaliplatin. Also, knockdown of miR-320 reversed these effects in HT-29 cells. Furthermore, we identified an oncogene, FOXM1, as a direct target of miR-320. In addition, miR-320 could inactive the activity of Wnt/β-catenin pathway. Finally, we found that miR-320 and FOXM1 protein had a negative correlation in colon cancer tissues and adjacent normal tissues. These findings implied that miR-320–FOXM1 axis may overcome chemo-resistance of colon cancer cells and provide a new therapeutic target for the treatment of colon cancer.

The intraportal injection model: A practical animal model for hepatic metastases and tumor cell dissemination in human colon cancer

International Nuclear Information System (INIS)

Thalheimer, Andreas; Waaga-Gasser, Ana M; Otto, Christoph; Bueter, Marco; Illert, Bertram; Gattenlohner, Stefan; Gasser, Martin; Meyer, Detlef; Fein, Martin; Germer, Christoph T

2009-01-01

The development of new therapeutic strategies for treatment of metastasized colorectal carcinoma requires biologically relevant and adequate animal models that generate both reproducible metastasis and the dissemination of tumor cells in the form of so-called minimal residual disease (MRD), an expression of the systemic character of neoplastic disease. We injected immunoincompetent nude mice intraportally with different numbers (1 × 10 5 , 1 × 10 6 and 5 × 10 6 cells) of the human colon carcinoma cell lines HT-29 and SW-620 and investigated by histological studies and CK-20 RT-PCR the occurrence of hematogenous metastases and the dissemination of human tumor cells in bone marrow. Only the injection of 1 × 10 6 cells of each colon carcinoma cell line produced acceptable perioperative mortality with reproducible induction of hepatic metastases in up to 89% of all animals. The injection of 1 × 10 6 cells also generated tumor cell dissemination in the bone marrow in up to 63% of animals with hepatic metastases. The present intraportal injection model in immunoincompetent nude mice represents a biologically relevant and adequate animal model for the induction of both reproducible hepatic metastasis and tumor cell dissemination in the bone marrow as a sign of MRD

SiRNA-mediated IGF-1R inhibition sensitizes human colon cancer SW480 cells to radiation

International Nuclear Information System (INIS)

Yavari, Kamal; Taghikhani, Mohammad; Mesbah-Namin, Seyed A.; Maragheh, Mohammad Ghannadi; Babaei, Mohammad Hosein; Arfaee, Ali Jabbary; Madani, Hossein; Mirzaei, Hamid Reza

2010-01-01

Purpose. Insulin like growth factor receptor 1 (IGF-1R) is well-documented to play a key role in radiation response and tumor radiosensitivity, thus offering an attractive clinic drug target to enhance tumor sensitivity to anti-cancer radiotherapy. Material and methods. Human colon carcinoma SW480 cells were transfected with the specific small interference RNA (siRNA) expression vector (pkD-shRNA-IGF-1R-V2) designed to target IGF-1R mRNA. The expression of IGF-1R mRNA and its protein among the transfected and untransfected cells were detected by semi-quantitative RT-PCR and ELISA assay. The changes in cell radiosensitivity were examined by MTT assay. Results. Transfection of mammalian expression vector pkD containing IGF-1R siRNA was shown to reduce IGF-1R mRNA levels by up to 95%. ELISA assay detected a similar inhibition of IGF-1R protein levels in cells transfected with IGF-1R siRNA. SW480 cells transfected with the expression vector for siRNA significantly rendered cells more sensitive to radiation and the highest radiation enhancement ratio was 2.02 ± 0.08. Conclusion. These data provide the first evidence that specific siRNA fragment (pkD-shRNA-IGF-1R-V2) targeting human IGF-1R mRNA is able to enhance colon cancer radiosensitivity. Also results indicated that, combining IGF-1R siRNA and radiation significantly enhances antitumor efficacy compared with either modality alone

Geoditin A Induces Oxidative Stress and Apoptosis on Human Colon HT29 Cells

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Wing-Keung Liu

2010-01-01

Full Text Available Geoditin A, an isomalabaricane triterpene isolated from the marine sponge Geodia japonica, has been demonstrated to dissipate mitochondrial membrane potential, activate caspase 3, decrease cytoplasmic proliferating cell nuclear antigen (PCNA, and induce apoptosis of leukemia cells, but the underlying mechanism remains unclear [1]. In this study, we found fragmentation of Golgi structure, suppression of transferrin receptor expression, production of oxidants, and DNA fragmentation in human colon cancer HT29 cells after treatment with geoditin A for 24 h. This apoptosis was not abrogated by chelation of intracellular iron with salicylaldehyde isonicotinoyl hydrazone (SIH, but suppressed by N-acetylcysteine (NAC, a thiol antioxidant and GSH precursor, indicating that the cytotoxic effect of geoditin A is likely mediated by a NAC-inhibitable oxidative stress. Our results provide a better understanding of the apoptotic properties and chemotherapeutical potential of this marine triterpene.

Factors that mediate colonization of the human stomach by Helicobacter pylori.

Science.gov (United States)

Dunne, Ciara; Dolan, Brendan; Clyne, Marguerite

2014-05-21

Helicobacter pylori (H. pylori) colonizes the stomach of humans and causes chronic infection. The majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial cells. The bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of disease. Colonization of gastric mucus is likely to be key to the establishment of chronic infection. How H. pylori manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this review. We also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different individuals. H. pylori infection of the gastric mucosa has become a paradigm for chronic infection. Understanding of why H. pylori is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease.

Effects of maple (Acer) plant part extracts on proliferation, apoptosis and cell cycle arrest of human tumorigenic and non-tumorigenic colon cells.

Science.gov (United States)

González-Sarrías, Antonio; Li, Liya; Seeram, Navindra P

2012-07-01

Phenolic-enriched extracts of maple sap and syrup, obtained from the sugar and red maple species (Acer saccharum Marsh, A. rubrum L., respectively), are reported to show anticancer effects. Despite traditional medicinal uses of various other parts of these plants by Native Americans, they have not been investigated for anticancer activity. Here leaves, stems/twigs, barks and sapwoods of both maple species were evaluated for antiproliferative effects against human colon tumorigenic (HCT-116, HT-29, Caco-2) and non-tumorigenic (CCD-18Co) cells. Extracts were standardized to total phenolic and ginnalin-A (isolated in our laboratory) levels. Overall, the extracts inhibited the growth of the colon cancer more than normal cells (over two-fold), their activities increased with their ginnalin-A levels, with red > sugar maple extracts. The red maple leaf extract, which contained the highest ginnalin-A content, was the most active extract (IC₅₀  = 35 and 16 µg/mL for extract and ginnalin-A, respectively). The extracts were not cytotoxic nor did they induce apoptosis of the colon cancer cells. However, cell cycle analyses revealed that the antiproliferative effects of the extracts were mediated through cell cycle arrest in the S-phase. The results from the current study suggest that these maple plant part extracts may have potential anticolon cancer effects. Copyright © 2011 John Wiley & Sons, Ltd.

MiR-145 regulates PAK4 via the MAPK pathway and exhibits an antitumor effect in human colon cells

International Nuclear Information System (INIS)

Wang, Zhigang; Zhang, Xiaoping; Yang, Zhili; Du, Hangxiang; Wu, Zhenqian; Gong, Jianfeng; Yan, Jun; Zheng, Qi

2012-01-01

Highlights: ► MiR-145 targets a putative binding site in the 3′UTR of PAK4. ► MiR-145 played an important role in inhibiting cell growth by directly targeting PAK4. ► MiR-145 may function as tumor suppressors. -- Abstract: MicroRNAs (miRNAs) are regulators of numerous cellular events; accumulating evidence indicates that miRNAs play a key role in a wide range of biological functions, such as cellular proliferation, differentiation, and apoptosis in cancer. Down-regulated expression of miR-145 has been reported in colon cancer tissues and cell lines. The molecular mechanisms underlying miR-145 and the regulation of colon carcinogenesis remain unclear. In this study, we investigated the levels of miR-145 in human colon cancer cells using qRT-PCR and found markedly decreased levels compared to normal epithelial cells. We identified PAK4 as a novel target of miR-145 using informatics screening. Additionally, we demonstrated that miR-145 targets a putative binding site in the 3′UTR of PAK4 and that its abundance is inversely associated with miR-145 expression in colon cancer cells; we confirmed this relationship using the luciferase reporter assay. Furthermore, restoration of miR-145 by mimics in SW620 cells significantly attenuated cell growth in vitro, in accordance with the inhibitory effects induced by siRNA mediated knockdown of PAK4. Taken together, these findings demonstrate that miR-145 downregulates P-ERK expression by targeting PAK4 and leads to inhibition of tumor growth.

Synergistic inhibitory effects of curcumin and 5-fluorouracil on the growth of the human colon cancer cell line HT-29.

Science.gov (United States)

Du, Boyu; Jiang, Liping; Xia, Quan; Zhong, Laifu

2006-01-01

The synergistic effect of combination treatment with COX-2 inhibitors and chemotherapy may be another promising therapy regimen in the future treatment of colorectal cancer. Curcumin, a major yellow pigment in turmeric which is used widely all over the world, inhibits the growth of human colon cancer cell line HT-29 significantly and specifically inhibits the expression of COX-2 protein. However, the worldwide exposure of populations to curcumin raised the question of whether this agent would enhance or inhibit the effects of chemotherapy. In this report, we evaluated the growth-inhibitory effect of curcumin and a traditional chemotherapy agent, 5-FU, against the proliferation of a human colon cancer cell line (HT-29). The combination effect was quantitatively determined using the method of median-effect principle and the combination index. The inhibition of COX-2 expression after treatment with the curcumin-5-FU combination was also evaluated by Western blot analysis. The IC(50) value in the HT-29 cells for curcumin was 15.9 +/- 1.96 microM and for 5-FU it was 17.3 +/- 1.85 microM. When curcumin and 5-FU were used concurrently, synergistic inhibition of growth was quantitatively demonstrated. The level of COX-2 protein expression was reduced almost 6-fold after the combination treatment. Our results demonstrate synergism between curcumin and 5-FU at higher doses against the human colon cancer cell line HT-29. This synergism was associated with the decreased expression of COX-2 protein. Copyright 2006 S. Karger AG, Basel.

Neural control of colonic cell proliferation.

Science.gov (United States)

Tutton, P J; Barkla, D H

1980-03-15

The mitotic rate in rat colonic crypts and in dimethylhydrazine-induced colonic carcinomas was measured using a stathmokinetic technique. In sympathectomized animals cell proliferation was retarded in the crypts but not in the tumors, whereas in animals treated with Metaraminol, a drug which releases norepinephrine from nerve terminals, crypt cell but not tumor cell proliferation was accelerated. Blockade of alpha-adrenoceptors also inhibited crypt cell proliferation. However, stimulation of beta-adrenoceptors inhibited and blockade of beta-adrenoceptors accelerated tumor cell proliferation without influencing crypt cell proliferation. Injection of either serotonin or histamine stimulated tumor but not crypt cell proliferation and blockade or serotonin receptors or histamine H2-receptors inhibited tumor cell proliferation. It is postulated that cell proliferation in the colonic crypts, like that in the jejunal crypts, is under both endocrine and autonomic neural control whereas colonic tumor cell division is subject to endocrine regulation alone.

Prostaglandin E2-Induced COX-2 Expressions via EP2 and EP4 Signaling Pathways in Human LoVo Colon Cancer Cells

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Hsi-Hsien Hsu

2017-05-01

Full Text Available Metastasis is the most dangerous risk faced by patients with hereditary non-polyposis colon cancer (HNPCC. The expression of matrix metalloproteinases (MMPs has been observed in several types of human cancers and regulates the efficacy of many therapies. Here, we show that treatment with various concentrations of prostaglandin E2 (PGE2; 0, 1, 5 or 10 μM promotes the migration ability of the human LoVo colon cancer cell line. As demonstrated by mRNA and protein expression analyses, EP2 and EP4 are the major PGE2 receptors expressed on the LoVo cell membrane. The Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K/Akt cell survival pathway was upregulated by EP2 and EP4 activation. Following the activation of the PI3K/Akt pathway, β-catenin translocated into the nucleus and triggered COX2 transcription via LEF-1 and TCF-4 and its subsequent translation. COX2 expression correlated with the elevation in the migration ability of LoVo cells. The experimental evidence shows a possible mechanism by which PGE2 induces cancer cell migration and further suggests PGE2 to be a potential therapeutic target in colon cancer metastasis. On inhibition of PGE2, in order to determine the downstream pathway, the levels of PI3K/Akt pathway were suppressed and the β-catenin expression was also modulated. Inhibition of EP2 and EP4 shows that PGE2 induces protein expression of COX-2 through EP2 and EP4 receptors in LoVo colon cancer cells.

Effects of cholera toxin on human colon carcinoma cell lines.

Science.gov (United States)

Barkla, D H; Whitehead, R H; Hayward, I P

1992-10-01

This study reports on changes in morphology and membrane transport in 5 human colon carcinoma cell lines treated with cholera toxin (CT). Three of the cell lines that grew as monolayers (LIM 1215, LIM 1899, LIM 2099) and 1 that grew as floating clumps (LIM 2408) did not show morphological changes after CT treatment. However, cell line LIM 1863 that grows as floating "crypt-like" organoids showed rapid and distinctive changes in morphology and membrane transport after CT treatment. At 1 and 6 hrs after CT treatment, light and transmission electron microscopy revealed rapid dilatation of the central lumen of organoids and the appearance of 2 populations of apical vesicular inclusions. The first population was unusual in being non-membrane bound and limited by fuzzy filamentous material. The second population was membrane bound. Scanning electron microscopy at 1-6 hr after CT treatment showed swelling and loss of surface microvilli on some, but not all, cells. At 24 hr after CT treatment the majority of organoids showed evidence of fluid accumulation and small apical vesicles coalesced to form large single vacuoles that obliterated normal cell morphology. By 48 hr, continued swelling produced extreme attenuation of the plasma membrane with cells taking on an "endothelial cell-like" appearance. The response to CT was dose-dependent. Uptake studies using 86Rubidium and blocking studies using ouabain and amiloride indicated that CT is acting on the Na+/K+ ATPase membrane pump to cause the increased fluid uptake by LIM 1863 cells. This study is the first to report specific morphological changes in intestine-derived cells in response to CT.(ABSTRACT TRUNCATED AT 250 WORDS)

Plant Polyphenols and Oxidative Metabolites of the Herbal Alkenylbenzene Methyleugenol Suppress Histone Deacetylase Activity in Human Colon Carcinoma Cells

Directory of Open Access Journals (Sweden)

Isabel Anna Maria Groh

2013-01-01

Full Text Available Evidence has been provided that diet and environmental factors directly influence epigenetic mechanisms associated with cancer development in humans. The inhibition of histone deacetylase (HDAC activity and the disruption of the HDAC complex have been recognized as a potent strategy for cancer therapy and chemoprevention. In the present study, we investigated whether selected plant constituents affect HDAC activity or HDAC1 protein status in the human colon carcinoma cell line HT29. The polyphenols (−-epigallocatechin-3-gallate (EGCG and genistein (GEN as well as two oxidative methyleugenol (ME metabolites were shown to inhibit HDAC activity in intact HT29 cells. Concomitantly, a significant decrease of the HDAC1 protein level was observed after incubation with EGCG and GEN, whereas the investigated ME metabolites did not affect HDAC1 protein status. In conclusion, dietary compounds were found to possess promising HDAC-inhibitory properties, contributing to epigenetic alterations in colon tumor cells, which should be taken into account in further risk/benefit assessments of polyphenols and alkenylbenzenes.

DK1 Induces Apoptosis via Mitochondria-Dependent Signaling Pathway in Human Colon Carcinoma Cell Lines In Vitro

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Yazmin Hussin

2018-04-01

Full Text Available Extensive research has been done in the search for innovative treatments against colon adenocarcinomas; however, the incidence rate of patients remains a major cause of cancer-related deaths in Malaysia. Natural bioactive compounds such as curcumin have been substantially studied as an alternative to anticancer drug therapies and have been surmised as a potent agent but, nevertheless, remain deficient due to its poor cellular uptake. Therefore, efforts now have shifted toward mimicking curcumin to synthesize novel compounds sharing similar effects. A synthetic analog, (Z-3-hydroxy-1-(2-hydroxyphenyl-3-phenylprop-2-ene-1-one (DK1, was recently synthesized and reported to confer improved bioavailability and selectivity toward human breast cancer cells. This study, therefore, aims to assess the anticancer mechanism of DK1 in relation to the induction of in vitro cell death in selected human colon cancer cell lines. Using the3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide(MTT assay, the cytotoxicity of DK1 towards HT29 and SW620 cell lines were investigated. Acridine orange/propidium iodide (AO/PI dual-staining assay and flow cytometry analyses (cell cycle analysis, Annexin/V-FITC and JC-1 assays were incorporated to determine the mode of cell death. To further determine the mechanism of cell death, quantitative real-time polymerase chain reaction (qRT-PCR and proteome profiling were conducted. Results from this study suggest that DK1 induced changes in cell morphology, leading to a decrease in cell viability and subsequent induction of apoptosis. DK1 treatment inhibited cell viability and proliferation 48 h post treatment with IC50 values of 7.5 ± 1.6 µM for HT29 cells and 14.5 ± 4.3 µM for SW620 cells, causing cell cycle arrest with increased accumulation of cell populations at the sub-G0/G1phaseof 74% and 23%, respectively. Flow cytometry analyses showed that DK1 treatment in cancer cells induced apoptosis, as indicated by DNA

Neurotensin-induced Erk1/2 phosphorylation and growth of human colonic cancer cells are independent from growth factors receptors activation

Energy Technology Data Exchange (ETDEWEB)

Massa, Fabienne; Tormo, Aurelie; Beraud-Dufour, Sophie; Coppola, Thierry [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France); Mazella, Jean, E-mail: mazella@ipmc.cnrs.fr [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France)

2011-10-14

Highlights: {yields} We compare intracellular pathways of NT and EGF in HT29 cells. {yields} NT does not transactivate EGFR. {yields} Transactivation of EGFR is not a general rule in cancer cell growth. -- Abstract: Neurotensin (NT) promotes the proliferation of human colonic cancer cells by undefined mechanisms. We already demonstrated that, in the human colon adenocarcinoma cell line HT29, the effects of NT were mediated by a complex formed between the NT receptor-1 (NTSR1) and-3 (NTSR3). Here we examined cellular mechanisms that led to NT-induced MAP kinase phosphorylation and growth factors receptors transactivation in colonic cancer cells and proliferation in HT29 cells. With the aim to identify upstream signaling involved in NT-elicited MAP kinase activation, we found that the stimulatory effects of the peptide were totally independent from the activation of the epidermal growth factor receptor (EGFR) both in the HT29 and the HCT116 cells. NT was unable to promote phosphorylation of EGFR and to compete with EGF for its binding to the receptor. Pharmacological approaches allowed us to differentiate EGF and NT signaling in HT29 cells since only NT activation of Erk1/2 was shown to be sensitive to PKC inhibitors and since only NT increased the intracellular level of calcium. We also observed that NT was not able to transactivate Insulin-like growth factor receptor. Our findings indicate that, in the HT29 and HCT116 cell lines, NT stimulates MAP kinase phosphorylation and cell growth by a pathway which does not involve EGF system but rather NT receptors which transduce their own intracellular effectors. These results indicate that depending on the cell line used, blocking EGFR is not the general rule to inhibit NT-induced cancer cell proliferation.

Effect of hydroxyapatite particle size, morphology and crystallinity on proliferation of colon cancer HCT116 cells

Energy Technology Data Exchange (ETDEWEB)

Dey, Sangeeta; Das, Mitun, E-mail: mitun@cgcri.res.in; Balla, Vamsi Krishna

2014-06-01

The aim of the present work is to chemically and physically characterize the synthesized Hydroxyapatite (HAp) micro and nanoparticles and to explore the inhibitory effect of nano-HAps on the in vitro growth of human colon cancerous cells HCT116. HAp powder was synthesized using three different routes to achieve micro and nanosized powders, with different morphologies and crystallinity. The synthesized powders were characterized using X-ray diffraction, FTIR spectroscopy and scanning electron microscope. The results showed that the average crystallite size of HAp powder varies from 11 nm to 177 nm and respective crystallinity of powder found to be in the range of 0.12 and 0.92. The effect of these physico-chemical properties of HAp powders on human colon cancer HCT116 cells inhibition was determined in vitro. It was found that decreasing the HAp powder crystallite size between 11 nm and 22 nm significantly increases the HCT116 cell inhibition. Our results demonstrate that apart from HAp powder size their crystallinity and morphology also play an important role in cellular inhibition of human colon cancer cells. - Highlights: • Chemically synthesized hydroxyapatite micro and nano-particles with different morphologies and crystallinity. • In vitro cell–material interaction showed that hydroxyapatite nano-particles inhibit colon cancer cells. • Human colon cancer cell inhibition also depends on crystallinity and morphology of HAp powder.

Pro-apoptotic and anti-proliferative effects of corn silk extract on human colon cancer cell lines.

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Guo, Hao; Guan, Hong; Yang, Wenqin; Liu, Han; Hou, Huiling; Chen, Xue; Liu, Zhenyan; Zang, Chuangang; Liu, Yuchao; Liu, Jicheng

2017-02-01

Corn silk is an economically and nutritionally significant natural product as it represents a staple food for a large proportion of the world population. This study investigated the anticancer activity of corn silk extract in human colon cancer cells and human gastric cancer cells. Following treatment with corn silk extract, certain apoptosis-related events were observed, including inhibition of cell proliferation, loss of mitochondrial membrane potential (ΔΨm), release of Ca2+ and release of cytochrome c from the mitochondria into the cytosol. Our results revealed that corn silk extract inhibited the proliferation of cancer cells and increased the level of apoptosis in a concentration-dependent manner. Western blot analysis revealed that corn silk extract upregulated the levels of Bax, cytochrome c , caspase-3 and caspase-9, but downregulated the levels of B-cell lymphoma 2. These results suggest that corn silk extract may induce apoptosis through the mitochondria-mediated pathway.

microRNA-365, down-regulated in colon cancer, inhibits cell cycle progression and promotes apoptosis of colon cancer cells by probably targeting Cyclin D1 and Bcl-2.

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Nie, Jing; Liu, Lin; Zheng, Wei; Chen, Lin; Wu, Xin; Xu, Yingxin; Du, Xiaohui; Han, Weidong

2012-01-01

Deregulated microRNAs participate in carcinogenesis and cancer progression, but their roles in cancer development remain unclear. In this study, miR-365 expression was found to be downregulated in human colon cancer tissues as compared with that in matched non-neoplastic mucosa tissues, and its downregulation was correlated with cancer progression and poor survival in colon cancer patients. Functional studies revealed that restoration of miR-365 expression inhibited cell cycle progression, promoted 5-fluorouracil-induced apoptosis and repressed tumorigenicity in colon cancer cell lines. Furthermore, bioinformatic prediction and experimental validation were used to identify miR-365 target genes and indicated that the antitumor effects of miR-365 were probably mediated by its targeting and repression of Cyclin D1 and Bcl-2 expression, thus inhibiting cell cycle progression and promoting apoptosis. These results suggest that downregulation of miR-365 in colon cancer may have potential applications in prognosis prediction and gene therapy in colon cancer patients.

Combination of gefitinib and DNA methylation inhibitor decitabine exerts synergistic anti-cancer activity in colon cancer cells.

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Yun-feng Lou

Full Text Available Despite recent advances in the treatment of human colon cancer, the chemotherapy efficacy against colon cancer is still unsatisfactory. In the present study, effects of concomitant inhibition of the epidermal growth factor receptor (EGFR and DNA methyltransferase were examined in human colon cancer cells. We demonstrated that decitabine (a DNA methyltransferase inhibitor synergized with gefitinib (an EGFR inhibitor to reduce cell viability and colony formation in SW1116 and LOVO cells. However, the combination of the two compounds displayed minimal toxicity to NCM460 cells, a normal human colon mucosal epithelial cell line. The combination was also more effective at inhibiting the AKT/mTOR/S6 kinase pathway. In addition, the combination of decitabine with gefitinib markedly inhibited colon cancer cell migration. Furthermore, gefitinib synergistically enhanced decitabine-induced cytotoxicity was primarily due to apoptosis as shown by Annexin V labeling that was attenuated by z-VAD-fmk, a pan caspase inhibitor. Concomitantly, cell apoptosis resulting from the co-treatment of gefitinib and decitabine was accompanied by induction of BAX, cleaved caspase 3 and cleaved PARP, along with reduction of Bcl-2 compared to treatment with either drug alone. Interestingly, combined treatment with these two drugs increased the expression of XIAP-associated factor 1 (XAF1 which play an important role in cell apoptosis. Moreover, small interfering RNA (siRNA depletion of XAF1 significantly attenuated colon cancer cells apoptosis induced by the combination of the two drugs. Our findings suggested that gefitinib in combination with decitabine exerted enhanced cell apoptosis in colon cancer cells were involved in mitochondrial-mediated pathway and induction of XAF1 expression. In conclusion, based on the observations from our study, we suggested that the combined administration of these two drugs might be considered as a novel therapeutic regimen for treating colon

Gemifloxacin, a Fluoroquinolone Antimicrobial Drug, Inhibits Migration and Invasion of Human Colon Cancer Cells

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Jung-Yu Kan

2013-01-01

Full Text Available Gemifloxacin (GMF is an orally administered broad-spectrum fluoroquinolone antimicrobial agent used to treat acute bacterial exacerbation of pneumonia and bronchitis. Although fluoroquinolone antibiotics have also been found to have anti-inflammatory and anticancer effects, studies on the effect of GMF on treating colon cancer have been relatively rare. To the best of our knowledge, this is the first report to describe the antimetastasis activities of GMF in colon cancer and the possible mechanisms involved. Results have shown that GMF inhibits the migration and invasion of colon cancer SW620 and LoVo cells and causes epithelial mesenchymal transition (EMT. In addition, GMF suppresses the activation of NF-κB and cell migration and invasion induced by TNF-α and inhibits the TAK1/TAB2 interaction, resulting in decreased IκB phosphorylation and NF-κB nuclear translocation in SW620 cells. Furthermore, Snail, a critical transcriptional factor of EMT, was downregulated after GMF treatment. Overexpression of Snail by cDNA transfection significantly decreases the inhibitory effect of GMF on EMT and cell migration and invasion. In conclusion, GMF may be a novel anticancer agent for the treatment of metastasis in colon cancer.

MicroRNA-215 suppresses cell proliferation, migration and invasion of colon cancer by repressing Yin-Yang 1

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Chen, Zehong; Han, Siqi; Huang, Wensheng; Wu, Jialin; Liu, Yuyi; Cai, Shirong; He, Yulong; Wu, Suijing; Song, Wu

2016-01-01

Colorectal cancer is one of the most common malignant tumors worldwide with rising incidence. MicroRNAs are small non-coding RNAs that implicate in multiple physiological or pathological processes. The aberrant expression of miRNA-215 (miR-215) has been illustrated in various types of cancers. However, the expression of miR-215 in human colon cancer and the biological roles of it remain largely unknown. We conducted this study to explore the expression and the function of miR-215 in human colon cancer. The results showed that miR-215 was remarkably downregulated in colon cancer tissues and cell lines. Overexpression of miR-215 by miR-215 mimic significantly inhibited colon cancer cell proliferation, migration and invasion while knockdown of miR-215 by miR-215 inhibitor exerted reverse effects. Furthermore, we newly identified Yin-Yang 1(YY1) as a direct target of miR-215 which could rescue the effects of miR-215 on colon cancer cells. In summary, our investigation revealed that miR-215 was downregulated in colon cancer and it suppressed colon cancer cell proliferation, migration and invasion by directly targeting YY1. - Highlights: • MiR-215 expression was decreased in colon cancer tissues and cell lines. • Mir-215 inhibited colon cancer cell proliferation, migration and invasion. • MiR-215 targeted YY1 directly. • The effects of miR-215 on colon cancer cells were mediated by YY1.

MiR-145 regulates PAK4 via the MAPK pathway and exhibits an antitumor effect in human colon cells

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Wang, Zhigang [Department of General Surgery, Shanghai Jiaotong University Affiliated 6th People' s Hospital, Shanghai (China); Zhang, Xiaoping [Department of Nuclear Medicine, Shanghai 10th People' s Hospital, Tongji University School of Medicine (China); Yang, Zhili; Du, Hangxiang; Wu, Zhenqian; Gong, Jianfeng; Yan, Jun [Department of General Surgery, Shanghai Jiaotong University Affiliated 6th People' s Hospital, Shanghai (China); Zheng, Qi, E-mail: zhengqi1957@yahoo.com.cn [Department of General Surgery, Shanghai Jiaotong University Affiliated 6th People' s Hospital, Shanghai (China)

2012-10-26

Highlights: Black-Right-Pointing-Pointer MiR-145 targets a putative binding site in the 3 Prime UTR of PAK4. Black-Right-Pointing-Pointer MiR-145 played an important role in inhibiting cell growth by directly targeting PAK4. Black-Right-Pointing-Pointer MiR-145 may function as tumor suppressors. -- Abstract: MicroRNAs (miRNAs) are regulators of numerous cellular events; accumulating evidence indicates that miRNAs play a key role in a wide range of biological functions, such as cellular proliferation, differentiation, and apoptosis in cancer. Down-regulated expression of miR-145 has been reported in colon cancer tissues and cell lines. The molecular mechanisms underlying miR-145 and the regulation of colon carcinogenesis remain unclear. In this study, we investigated the levels of miR-145 in human colon cancer cells using qRT-PCR and found markedly decreased levels compared to normal epithelial cells. We identified PAK4 as a novel target of miR-145 using informatics screening. Additionally, we demonstrated that miR-145 targets a putative binding site in the 3 Prime UTR of PAK4 and that its abundance is inversely associated with miR-145 expression in colon cancer cells; we confirmed this relationship using the luciferase reporter assay. Furthermore, restoration of miR-145 by mimics in SW620 cells significantly attenuated cell growth in vitro, in accordance with the inhibitory effects induced by siRNA mediated knockdown of PAK4. Taken together, these findings demonstrate that miR-145 downregulates P-ERK expression by targeting PAK4 and leads to inhibition of tumor growth.

Functional heterogeneity of cancer-associated fibroblasts from human colon tumors shows specific prognostic gene expression signature.

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Herrera, Mercedes; Islam, Abul B M M K; Herrera, Alberto; Martín, Paloma; García, Vanesa; Silva, Javier; Garcia, Jose M; Salas, Clara; Casal, Ignacio; de Herreros, Antonio García; Bonilla, Félix; Peña, Cristina

2013-11-01

Cancer-associated fibroblasts (CAF) actively participate in reciprocal communication with tumor cells and with other cell types in the microenvironment, contributing to a tumor-permissive neighborhood and promoting tumor progression. The aim of this study is the characterization of how CAFs from primary human colon tumors promote migration of colon cancer cells. Primary CAF cultures from 15 primary human colon tumors were established. Their enrichment in CAFs was evaluated by the expression of various epithelial and myofibroblast specific markers. Coculture assays of primary CAFs with different colon tumor cells were performed to evaluate promigratory CAF-derived effects on cancer cells. Gene expression profiles were developed to further investigate CAF characteristics. Coculture assays showed significant differences in fibroblast-derived paracrine promigratory effects on cancer cells. Moreover, the association between CAFs' promigratory effects on cancer cells and classic fibroblast activation or stemness markers was observed. CAF gene expression profiles were analyzed by microarray to identify deregulated genes in different promigratory CAFs. The gene expression signature, derived from the most protumorogenic CAFs, was identified. Interestingly, this "CAF signature" showed a remarkable prognostic value for the clinical outcome of patients with colon cancer. Moreover, this prognostic value was validated in an independent series of 142 patients with colon cancer, by quantitative real-time PCR (qRT-PCR), with a set of four genes included in the "CAF signature." In summary, these studies show for the first time the heterogeneity of primary CAFs' effect on colon cancer cell migration. A CAF gene expression signature able to classify patients with colon cancer into high- and low-risk groups was identified.

Genetics and biochemistry of collagen binding-triggered glandular differentiation in a human colon carcinoma cell line

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Pignatelli, M.; Bodmer, W.F.

1988-01-01

The authors have examined the interaction between collagen binding and epithelial differentiation by using a human colon carcinoma cell line (SW1222) that can differentiate structurally when grown in a three-dimensional collagen gel to form glandular structures. As much as 66% inhibition of glandular differentiation can be achieved by addition to the culture of a synthetic peptide containing the Arg-Gly-Asp-Thr (RGDT) sequence, which is a cell recognition site found in collagen. Arg-Gly-Asp-Thr also inhibited the cell attachment to collagen-coated plates. Chromosome 15 was found in all human-mouse hybrid clones that could differentiate in the collagen gel and bind collagen. Both binding to collagen and glandular differentiation of the hybrid cells were also inhibited by Arg-Gly-Asp-Thr as for the parent cell line SW1222. The ability of SW1222 cells to express the differentiated phenotype appears, therefore, to be determined by an Arg-Gly-Asp-directed collagen receptor on the cell surface that is controlled by a gene on chromosome 15

CD133 expression is not restricted to stem cells, and both CD133+ and CD133– metastatic colon cancer cells initiate tumors

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Shmelkov, Sergey V.; Butler, Jason M.; Hooper, Andrea T.; Hormigo, Adilia; Kushner, Jared; Milde, Till; St. Clair, Ryan; Baljevic, Muhamed; White, Ian; Jin, David K.; Chadburn, Amy; Murphy, Andrew J.; Valenzuela, David M.; Gale, Nicholas W.; Thurston, Gavin; Yancopoulos, George D.; D’Angelica, Michael; Kemeny, Nancy; Lyden, David; Rafii, Shahin

2008-01-01

Colon cancer stem cells are believed to originate from a rare population of putative CD133+ intestinal stem cells. Recent publications suggest that a small subset of colon cancer cells expresses CD133, and that only these CD133+ cancer cells are capable of tumor initiation. However, the precise contribution of CD133+ tumor-initiating cells in mediating colon cancer metastasis remains unknown. Therefore, to temporally and spatially track the expression of CD133 in adult mice and during tumorigenesis, we generated a knockin lacZ reporter mouse (CD133lacZ/+), in which the expression of lacZ is driven by the endogenous CD133 promoters. Using this model and immunostaining, we discovered that CD133 expression in colon is not restricted to stem cells; on the contrary, CD133 is ubiquitously expressed on differentiated colonic epithelium in both adult mice and humans. Using Il10–/–CD133lacZ mice, in which chronic inflammation in colon leads to adenocarcinomas, we demonstrated that CD133 is expressed on a full gamut of colonic tumor cells, which express epithelial cell adhesion molecule (EpCAM). Similarly, CD133 is widely expressed by human primary colon cancer epithelial cells, whereas the CD133– population is composed mostly of stromal and inflammatory cells. Conversely, CD133 expression does not identify the entire population of epithelial and tumor-initiating cells in human metastatic colon cancer. Indeed, both CD133+ and CD133– metastatic tumor subpopulations formed colonospheres in in vitro cultures and were capable of long-term tumorigenesis in a NOD/SCID serial xenotransplantation model. Moreover, metastatic CD133– cells form more aggressive tumors and express typical phenotypic markers of cancer-initiating cells, including CD44 (CD44+CD24–), whereas the CD133+ fraction is composed of CD44lowCD24+ cells. Collectively, our data suggest that CD133 expression is not restricted to intestinal stem or cancer-initiating cells, and during the metastatic

Butyrate and deoxycholic acid play common and distinct roles in HCT116 human colon cell proliferation.

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Zeng, Huawei; Claycombe, Kate J; Reindl, Katie M

2015-10-01

Consumption of a high-fat diet causes an increase in bile acid deoxycholic acid (DCA) in colon lumen and colon cancer risk, while butyrate, an intestinal microbiota metabolite of dietary fiber, has been shown to exhibit colon cancer-preventive effects. To distinguish these opposing effects of DCA and butyrate (two major metabolites in colon lumen), we examined the effects of physiologically relevant doses of butyrate (0.5-2 mmol/l) and DCA (0.05-0.3 mmol/l) on colon cell proliferation. We hypothesize that butyrate and DCA each modulates the cell cycle and apoptosis via common and distinct cellular signaling targets. In this study, we demonstrated that both butyrate and DCA inhibited cell proliferation by up to 89% and 92% and increased cell apoptosis rate by up to 3.1- and 4.5-fold, respectively. Cell cycle analyses revealed that butyrate led to an increase in G1 and G2 fractions with a concomitant drop in the S-phase fraction, but DCA induced an increase in only G1 fraction with a concomitant drop in the S-phase fraction when compared with the untreated cells. The examination of early cellular signaling revealed that DCA but not butyrate increased intracellular reactive oxygen species, genomic DNA breakage, the activation of ERK1/2, caspase-3 and PARP. In contrast, DCA decreased activated Rb protein level, and butyrate but not DCA increased p21 expression. Collectively, although both butyrate and DCA inhibit colonic cell proliferation, butyrate increases tumor suppressor gene expression, whereas DCA decreases tumor suppressor activation in cell cycle and apoptosis pathways. Published by Elsevier Inc.

Antiproliferative Effects of Bacillus coagulans Unique IS2 in Colon Cancer Cells.

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Madempudi, Ratna Sudha; Kalle, Arunasree M

2017-10-01

In the present study, the in vitro anticancer (antiproliferative) effects of Bacillus coagulans Unique IS2 were evaluated on human colon cancer (COLO 205), cervical cancer (HeLa), and chronic myeloid leukemia (K562) cell lines with a human embryonic kidney cell line (HEK 293T) as noncancerous control cells. The Cytotoxicity assay (MTT) clearly demonstrated a 22%, 31.7%, and 19.5% decrease in cell proliferation of COLO 205, HeLa, and K562 cells, respectively, when compared to the noncancerous HEK 293T cells. Normal phase-contrast microscopic images clearly suggested that the mechanism of cell death is by apoptosis. To further confirm the induction of apoptosis by Unique IS2, the sub-G0-G1 peak of the cell cycle was quantified using a flow cytometer and the data indicated 40% of the apoptotic cells in Unique IS2-treated COLO cells when compared with their untreated control cells. The Western blot analysis showed an increase in pro-apoptotic protein BAX, decrease in antiapoptotic protein, Bcl2, decrease in mitochondrial membrane potential, increase in cytochrome c release, increase in Caspase 3 activity, and cleavage of poly(ADP-ribose) polymerase. The present study suggests that the heat-killed culture supernatant of B. coagulans can be more effective in inducing apoptosis of colon cancer cells and that can be considered for adjuvant therapy in the treatment of colon carcinoma.

A paraptosis-like cell death induced by δ-tocotrienol in human colon carcinoma SW620 cells is associated with the suppression of the Wnt signaling pathway

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Zhang, Jing-Shu; Li, Da-Ming; He, Ning; Liu, Ying-Hua; Wang, Chun-Hua; Jiang, Shu-Qing; Chen, Bing-Qing; Liu, Jia-Ren

2011-01-01

Tocotrienol is considered a beneficial effect agent on inhibition of tumor development. In this study, we focused on the effects of δ-tocotrienol and its possible mechanism on induction of death in human colon cancer SW620 cells. δ-Tocotrienol inhibited proliferation of SW620 cell in a dose-dependent manner. Our findings showed that δ-tocotrienol effectively induced paraptosis-like death in SW620 cells, correlated with the vacuolation that may be from welling and fusion of mitochondria and/or the endoplasmic reticulum (ER) as well as caspase-3 nonactivated. However, there were no changes in apoptosis based on flow cytometry analysis. Of being noted, δ-tocotrienol reduced the expression of β-catenin and wnt-1 proteins by about 50% at the highest dose (20 μmol/L). δ-Tocotrienol also decreased cyclin D1, c-jun and MMP-7 protein levels in SW620 cells. Altogether, these data indicate that δ-tocotrienol induces paraptosis-like cell death, which is associated with the suppression of the Wnt signaling pathway. Thus, our findings may provide a novel application in treatment of human colon carcinoma.

ETV4 and Myeov knockdown impairs colon cancer cell line proliferation and invasion

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Moss, Alan C.; Lawlor, Garrett; Murray, David; Tighe, Donal; Madden, Stephen F.; Mulligan, Anne-Marie; Keane, Conor O.; Brady, Hugh R.; Doran, Peter P.; MacMathuna, Padraic

2006-01-01

We have identified novel colorectal cancer-associated genes using NCBI's UNIGENE cDNA libraries. Colon cancer libraries were examined using Digital Differential Display and disease-associated genes were selected. Among these were ETV4 and MYEOV, novel colorectal cancer-associated genes. Samples of matched normal and neoplastic colon were obtained from human subjects and gene expression was quantified using real-time PCR. ETV4 gene expression was significantly increased in colonic neoplasia in comparison to matched normal colonic tissue (p < 0.05). Myeov expression was also increased in colon neoplasia in comparison to matched normal tissue. The effect of siRNA-mediated knockdown of ETV4 and Myeov on cell proliferation and invasion was assessed. ETV4 knockdown resulted in a 90% decrease in cell proliferation (p < 0.05) and a 67% decrease in cell invasion. Myeov knockdown resulted in a 48% decrease in cell proliferation (p < 0.05) and a 36% decrease in cell invasion. These data suggest that ETV4 and Myeov may provide novel targets for therapeutic intervention

CD4CD8αα lymphocytes, a novel human regulatory T cell subset induced by colonic bacteria and deficient in patients with inflammatory bowel disease.

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Guillaume Sarrabayrouse

2014-04-01

Full Text Available How the microbiota affects health and disease is a crucial question. In mice, gut Clostridium bacteria are potent inducers of colonic interleukin (IL-10-producing Foxp3 regulatory T cells (Treg, which play key roles in the prevention of colitis and in systemic immunity. In humans, although gut microbiota dysbiosis is associated with immune disorders, the underlying mechanism remains unknown. In contrast with mice, the contribution of Foxp3 Treg in colitis prevention has been questioned, suggesting that other compensatory regulatory cells or mechanisms may exist. Here we addressed the regulatory role of the CD4CD8 T cells whose presence had been reported in the intestinal mucosa and blood. Using colonic lamina propria lymphocytes (LPL and peripheral blood lymphocytes (PBL from healthy individuals, and those with colon cancer and irritable bowel disease (IBD, we demonstrated that CD4CD8αα (DP8α T lymphocytes expressed most of the regulatory markers and functions of Foxp3 Treg and secreted IL-10. Strikingly, DP8α LPL and PBL exhibited a highly skewed repertoire toward the recognition of Faecalibacterium prausnitzii, a major Clostridium species of the human gut microbiota, which is decreased in patients with IBD. Furthermore, the frequencies of DP8α PBL and colonic LPL were lower in patients with IBD than in healthy donors and in the healthy mucosa of patients with colon cancer, respectively. Moreover, PBL and LPL from most patients with active IBD failed to respond to F. prausnitzii in contrast to PBL and LPL from patients in remission and/or healthy donors. These data (i uncover a Clostridium-specific IL-10-secreting Treg subset present in the human colonic LP and blood, (ii identify F. prausnitzii as a major inducer of these Treg, (iii argue that these cells contribute to the control or prevention of colitis, opening new diagnostic and therapeutic strategies for IBD, and (iv provide new tools to address the systemic impact of both these Treg

Human wound colonization by Lucilia eximia and Chrysomya rufifacies (Diptera: Calliphoridae): myiasis, perimortem, or postmortem colonization?

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Sanford, Michelle R; Whitworth, Terry L; Phatak, Darshan R

2014-05-01

The infestation of human or animal tissues by fly larvae has been given distinctive terminology depending on the timing and location of colonization. Wounds and orifices colonized by Diptera in a living human or animal are typically referred to as myiasis. When the colonization occurs after death, it is referred to as postmortem colonization and can be used to estimate the minimum postmortem interval. What happens when the human, as in the case presented here, has a necrotic limb while the human remains alive, at least for a short period of time? The case presented here documents perimortem wound colonization by Lucilia eximia (Wiedemann) and Chrysomya rufifacies (Macquart) and the considerations for approximating development temperatures and estimating the time of colonization (TOC). This represents the first record of L. eximia in human myiasis in the United States and the first record of the co-occurrence of L. eximia and C. rufifacies in human myiasis in the United States. The TOC was estimated using both ambient and body temperature. Insect colonization before death complicates the estimation of TOC and minimum postmortem interval and illustrates the problem of temperature approximation in forensic entomology casework.

Hydrogen sulfide lowers proliferation and induces protective autophagy in colon epithelial cells.

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Ya C Wu

Full Text Available Hydrogen sulfide (H(2S is a gaseous bacterial metabolite that reaches high levels in the large intestine. In the present study, the effect of H(2S on the proliferation of normal and cancerous colon epithelial cells was investigated. An immortalized colon epithelial cell line (YAMC and a panel of colon cancer cell lines (HT-29, SW1116, HCT116 were exposed to H(2S at concentrations similar to those found in the human colon. H(2S inhibited normal and cancerous colon epithelial cell proliferation as measured by MTT assay. The anti-mitogenic effect of H(2S was accompanied by G(1-phase cell cycle arrest and the induction of the cyclin-dependent kinase inhibitor p21(Cip. Moreover, exposure to H(2S led to features characteristic of autophagy, including increased formation of LC3B(+ autophagic vacuoles and acidic vesicular organelles as determined by immunofluorescence and acridine orange staining, respectively. Abolition of autophagy by RNA interference targeting Vps34 or Atg7 enhanced the anti-proliferative effect of H(2S. Further mechanistic investigation revealed that H(2S stimulated the phosphorylation of AMP-activated protein kinase (AMPK and inhibited the phosphorylation of mammalian target of rapamycin (mTOR and S6 kinase. Inhibition of AMPK significantly reversed H(2S-induced autophagy and inhibition of cell proliferation. Collectively, we demonstrate that H(2S inhibits colon epithelial cell proliferation and induces protective autophagy via the AMPK pathway.

Colon stem cell and crypt dynamics exposed by cell lineage reconstruction.

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Yitzhak Reizel

2011-07-01

Full Text Available Stem cell dynamics in vivo are often being studied by lineage tracing methods. Our laboratory has previously developed a retrospective method for reconstructing cell lineage trees from somatic mutations accumulated in microsatellites. This method was applied here to explore different aspects of stem cell dynamics in the mouse colon without the use of stem cell markers. We first demonstrated the reliability of our method for the study of stem cells by confirming previously established facts, and then we addressed open questions. Our findings confirmed that colon crypts are monoclonal and that, throughout adulthood, the process of monoclonal conversion plays a major role in the maintenance of crypts. The absence of immortal strand mechanism in crypts stem cells was validated by the age-dependent accumulation of microsatellite mutations. In addition, we confirmed the positive correlation between physical and lineage proximity of crypts, by showing that the colon is separated into small domains that share a common ancestor. We gained new data demonstrating that colon epithelium is clustered separately from hematopoietic and other cell types, indicating that the colon is constituted of few progenitors and ruling out significant renewal of colonic epithelium from hematopoietic cells during adulthood. Overall, our study demonstrates the reliability of cell lineage reconstruction for the study of stem cell dynamics, and it further addresses open questions in colon stem cells. In addition, this method can be applied to study stem cell dynamics in other systems.

BG-4, a novel anticancer peptide from bitter gourd (Momordica charantia), promotes apoptosis in human colon cancer cells.

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Dia, Vermont P; Krishnan, Hari B

2016-09-15

Momordica charantia is a perennial plant with reported health benefits. BG-4, a novel peptide from Momordica charantia, was isolated, purified and characterized. The trypsin inhibitory activity of BG-4 is 8.6 times higher than purified soybean trypsin inhibitor. The high trypsin inhibitory activity of BG-4 may be responsible for its capability to cause cytotoxicity to HCT-116 and HT-29 human colon cancer cells with ED50 values of 134.4 and 217.0 μg/mL after 48 h of treatment, respectively. The mechanism involved in the cytotoxic effect may be associated with induction of apoptosis as evidenced by increased percentage of HCT-116 and HT-29 colon cancer cells undergoing apoptosis from 5.4% (untreated) to 24.8% (BG-4 treated, 125 μg/mL for 16 h) and 8.5% (untreated) to 31.9% (BG-4 treated, 125 μg/mL for 16 h), respectively. The molecular mechanistic explanation in the apoptosis inducing property of BG-4 is due to reduced expression of Bcl-2 and increased expression of Bax leading to increased expression of caspase-3 and affecting the expression of cell cycle proteins p21 and CDK2. This is the first report on the anti-cancer potential of a novel bioactive peptide isolated from Momordica charantia in vitro supporting the potential therapeutic property of BG-4 against colon cancer that must be addressed using in vivo models of colon carcinogenesis.

A CASE REPORT OF MULTIPLE PRIMARY SQUAMOUS CELL CARCINOMAS OF THE OVARY AND SIGMOID COLON

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A. B. Villert

2016-01-01

Full Text Available Squamous cell ovarian and sigmoid colon carcinomas are extremely rare malignancies. Because of their rarity, it is difficult to investigate the clinical characteristics and prognosis of patients with theses malignancies, and therefore, the increased interest in each clinical case report is highly relevant. Multiple primary squamous cell ovarian and sigmoid colon carcinomas are the subject of discussion and differential diagnosis of sigmoid colon cancer with secondary ovarian cancer. Histopathological and clinical characteristics of the tumors were present and evidences in favor of the multiple primary malignancies were given. The association of squamous cell ovarian and sigmoid colon carcinomas with human papilloma virus type 16 was shown.

Phyllanthus emblica Fruit Extract Activates Spindle Assembly Checkpoint, Prevents Mitotic Aberrations and Genomic Instability in Human Colon Epithelial NCM460 Cells

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Xihan Guo

2016-09-01

Full Text Available The fruit of Phyllanthus emblica Linn. (PE has been widely consumed as a functional food and folk medicine in Southeast Asia due to its remarkable nutritional and pharmacological effects. Previous research showed PE delays mitotic progress and increases genomic instability (GIN in human colorectal cancer cells. This study aimed to investigate the similar effects of PE by the biomarkers related to spindle assembly checkpoint (SAC, mitotic aberrations and GIN in human NCM460 normal colon epithelial cells. Cells were treated with PE and harvested differently according to the biomarkers observed. Frequencies of micronuclei (MN, nucleoplasmic bridge (NPB and nuclear bud (NB in cytokinesis-block micronucleus assay were used as indicators of GIN. Mitotic aberrations were assessed by the biomarkers of chromosome misalignment, multipolar division, chromosome lagging and chromatin bridge. SAC activity was determined by anaphase-to- metaphase ratio (AMR and the expression of core SAC gene budding uninhibited by benzimidazoles related 1 (BubR1. Compared with the control, PE-treated cells showed (1 decreased incidences of MN, NPB and NB (p < 0.01; (2 decreased frequencies of all mitotic aberration biomarkers (p < 0.01; and (3 decreased AMR (p < 0.01 and increased BubR1 expression (p < 0.001. The results revealed PE has the potential to protect human normal colon epithelial cells from mitotic and genomic damages partially by enhancing the function of SAC.

Reduction of Orc6 expression sensitizes human colon cancer cells to 5-fluorouracil and cisplatin.

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Elaine J Gavin

Full Text Available Previous studies from our group have shown that the expression levels of Orc6 were highly elevated in colorectal cancer patient specimens and the induction of Orc6 was associated with 5-fluorouracil (5-FU treatment. The goal of this study was to investigate the molecular and cellular impact of Orc6 in colon cancer. In this study, we use HCT116 (wt-p53 and HCT116 (null-p53 colon cancer cell lines as a model system to investigate the impact of Orc6 on cell proliferation, chemosensitivity and pathways involved with Orc6. We demonstrated that the down regulation of Orc6 sensitizes colon cancer cells to both 5-FU and cisplatin (cis-pt treatment. Decreased Orc6 expression in HCT-116 (wt-p53 cells by RNA interference triggered cell cycle arrest at G1 phase. Prolonged inhibition of Orc6 expression resulted in multinucleated cells in HCT-116 (wt-p53 cell line. Western immunoblot analysis showed that down regulation of Orc6 induced p21 expression in HCT-116 (wt-p53 cells. The induction of p21 was mediated by increased level of phosphorylated p53 at ser-15. By contrast, there is no elevated expression of p21 in HCT-116 (null-p53 cells. Orc6 down regulation also increased the expression of DNA damaging repair protein GADD45beta and reduced the expression level of JNK1. Orc6 may be a potential novel target for future anti cancer therapeutic development in colon cancer.

MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling

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Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

2005-01-01

It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer. PMID:15785735

Decreased Polyunsaturated Fatty Acid Content Contributes to Increased Survival in Human Colon Cancer

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Manuela Oraldi

2009-01-01

Full Text Available Among diet components, some fatty acids are known to affect several stages of colon carcinogenesis, whereas others are probably helpful in preventing tumors. In light of this, our aim was to determine the composition of fatty acids and the possible correlation with apoptosis in human colon carcinoma specimens at different Duke's stages and to evaluate the effect of enriching human colon cancer cell line with the possible reduced fatty acid(s. Specimens of carcinoma were compared with the corresponding non-neoplastic mucosa: a significant decrease of arachidonic acid, PPARα, Bad, and Bax and a significant increase of COX-2, Bcl-2, and pBad were found. The importance of arachidonic acid in apoptosis was demonstrated by enriching a Caco-2 cell line with this fatty acid. It induced apoptosis in a dose- and time-dependent manner via induction of PPARα that, in turn, decreased COX-2. In conclusion, the reduced content of arachidonic acid is likely related to carcinogenic process decreasing the susceptibility of cancer cells to apoptosis.

γ-Aminobutyric acid inhibits the proliferation and increases oxaliplatin sensitivity in human colon cancer cells.

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Song, Lihua; Du, Aiying; Xiong, Ying; Jiang, Jing; Zhang, Yao; Tian, Zhaofeng; Yan, Hongli

2016-11-01

γ-Aminobutyric acid (GABA) is a natural non-protein amino acid, which broadly exists in many plant parts and is widely used as an ingredient in the food industry. In mammals, it is widely distributed in central nervous system and non-neural tissues. In addition to a primary inhibitory neurotransmitter in the central nervous system, endogenous GABA content has been found to be elevated in neoplastic tissues in colon cancer. However, the effect of extraneous GABA on colon cancer has rarely been reported. In this study, we found the inhibitory effects of GABA on the proliferation of colon cancer cells (CCCs). The amino acid also suppressed metastasis of SW480 and SW620 cells. To further study the correlated mechanism, we analyzed the changes in cell cycle distribution and found that GABA suppressed cell cycle progression through G2/M or G1/S phase. Furthermore, RNA sequencing analysis revealed GABA-induced changes in the mRNA expression of 30 genes, including EGR1, MAPK4, NR4A1, Fos, and FosB, in all the three types of CCC. Importantly, GABA enhanced the anti-tumor efficacy of oxaliplatin (OXA) in subcutaneous xenograft tumor model in nude mice. The data suggest that GABA inhibits colon cancer cell proliferation perhaps by attenuating EGR1-NR4A1 axis, EGR1-Fos axis, and by disrupting MEK-EGR1 signaling pathway. This work reveals the pharmacological value of GABA derived from food and suggests that exogenous GABA might play an auxiliary role in polychemotherapy of colon cancer.

The evaluation of interstitial Cajal cells distribution in non-tumoral colon disorders.

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Becheanu, G; Manuc, M; Dumbravă, Mona; Herlea, V; Hortopan, Monica; Costache, Mariana

2008-01-01

Interstitial cells of Cajal (ICC) are pacemakers that generate electric waves recorded from the gut and are important for intestinal motility. The aim of the study was to evaluate the distribution of interstitial cells of Cajal in colon specimens from patients with idiopathic chronic pseudo-obstruction and other non-tumoral colon disorders as compared with samples from normal colon. The distribution pattern of ICC in the normal and pathological human colon was evaluated by immunohistochemistry using antibodies for CD117, CD34, and S-100. In two cases with intestinal chronic idiopathic pseudo-obstruction we found a diffuse or focal reducing number of Cajal cells, the loss of immunoreactivity for CD117 being correlated with loss of immunoreactivity for CD34 marker. Our study revealed that the number of interstitial cells of Cajal also decrease in colonic diverticular disease and Crohn disease (p<0.05), whereas the number of enteric neurones appears to be normal. These findings might explain some of the large bowel motor abnormalities known to occur in these disorders. Interstitial Cajal cells may play an important role in pathogenesis and staining for CD117 on transmural intestinal surgical biopsies could allow a more extensive diagnosis in evaluation of chronic intestinal pseudo-obstruction.

Promoter hypermethylation mediated downregulation of FBP1 in human hepatocellular carcinoma and colon cancer.

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Mingquan Chen

Full Text Available FBP1, fructose-1,6-bisphosphatase-1, a gluconeogenesis regulatory enzyme, catalyzes the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphate. The mechanism that it functions to antagonize glycolysis and was epigenetically inactivated through NF-kappaB pathway in gastric cancer has been reported. However, its role in the liver carcinogenesis still remains unknown. Here, we investigated the expression and DNA methylation of FBP1 in primary HCC and colon tumor. FBP1 was lowly expressed in 80% (8/10 human hepatocellular carcinoma, 66.7% (6/9 liver cancer cell lines and 100% (6/6 colon cancer cell lines, but was higher in paired adjacent non-tumor tissues and immortalized normal cell lines, which was well correlated with its promoter methylation status. Methylation was further detected in primary HCCs, gastric and colon tumor tissues, but none or occasionally in paired adjacent non-tumor tissues. Detailed methylation analysis of 29 CpG sites at a 327-bp promoter region by bisulfite genomic sequencing confirmed its methylation. FBP1 silencing could be reversed by chemical demethylation treatment with 5-aza-2'-deoxycytidine (Aza, indicating direct epigenetic silencing. Restoring FBP1 expression in low expressed cells significantly inhibited cell growth and colony formation ability through the induction of G2-M phase cell cycle arrest. Moreover, the observed effects coincided with an increase in reactive oxygen species (ROS generation. In summary, epigenetic inactivation of FBP1 is also common in human liver and colon cancer. FBP1 appears to be a functional tumor suppressor involved in the liver and colon carcinogenesis.

Synthesis of glycosaminoglycans by undifferentiated and differentiated HT29 human colonic cancer cells.

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Simon-Assmann, P; Bouziges, F; Daviaud, D; Haffen, K; Kedinger, M

1987-08-15

Among the extracellular matrix components which have been suggested to be involved in developmental and neoplastic changes are glycosaminoglycans (GAGs). To try to correlate their amount and nature with the process of enterocytic differentiation, we studied glycosaminoglycan synthesis of human colonic adenocarcinoma cells (HT29 cell line) by [3H]glucosamine and [35S]sulfate incorporation. Enterocytic differentiation of the cells obtained in a sugar-free medium (for review, see A. Zweibaum et al. In: Handbook of Physiology. Intestinal Transport of the Gastrointestinal System, in press, 1987) resulted in a marked increase in total incorporation of labeled precursors (20-fold for [3H]glucosamine, 4.5-fold for [35S]sulfate) as well as in uronic acid content (5-fold); most of the synthesized GAGs were found associated with the cell pellet. Chromatographic and electrophoretic analysis of the labeled GAGs revealed that undifferentiated cells synthesized and secreted hyaluronic acid, heparan sulfate, and one class of chondroitin sulfate. Differentiation of HT29 cells because associated with the synthesis of an additional class of chondroitin sulfate (CS4) concomitant to a decrease in heparan sulfate which is no longer found secreted in the medium. Furthermore, the charge density of this latter GAG component varied as assessed by a shift of its affinity on ion-exchange chromatography.

Chemical synthesis, docking studies and biological effects of functionalized 1,3-diaryl-2-propen-1-ones on human colon cancer cells

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Guo-Min Zhu

2015-03-01

Full Text Available A series of 1, 3-diaryl-2-propen-1-ones was synthesised in order to obtain a new type of anticancer drug, designed with hybrid features to inhibit colon cancer activated receptor. Based on computational modelling and docking studies, potential inhibitors were synthesised and their biological activity evaluated. The structures of newly synthesized compounds were confirmed by 1HNMR, 13CNMR and Mass spectrometry. All analogues were evaluated for in vitro cytotoxicity against human colon (caco-2 cancer cell lines. Compounds 1b, 1f-1h, and 2i showed significant cytotoxicity. Chalcones 1b, 1f and 1g were identified as the most potent and selective anticancer agents with IC50 values <1 µg/mL and 1.5 µg/mL, against caco-2 cell line, respectively. In conclusion, this finding confirms the suitability of indolyl chalcone analogues as candidates for further investigation towards the management of colon cancer related diseases.

Strawberry-Tree Honey Induces Growth Inhibition of Human Colon Cancer Cells and Increases ROS Generation: A Comparison with Manuka Honey.

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Afrin, Sadia; Forbes-Hernandez, Tamara Y; Gasparrini, Massimiliano; Bompadre, Stefano; Quiles, José L; Sanna, Gavino; Spano, Nadia; Giampieri, Francesca; Battino, Maurizio

2017-03-11

Honey is a natural product known to modulate several biological activities including cancer. The aim of the present study was to examine the phytochemical content and the antioxidant activity of Strawberry tree ( Arbutus unedo ) honey (STH) and its cytotoxic properties against human colon adenocarcinoma (HCT-116) and metastatic (LoVo) cell lines in comparison with Manuka ( Leptospermum scoparium ) honey (MH). Several unifloral STH and MH were analyzed for their phenolic, flavonoid, amino acid and protein contents, as well as their radical scavenging activities. STH from the Berchidda area showed the highest amount of phenolic, flavonoid, amino acid and protein content, and antioxidant capacity compared to MH. Both STH and MH induced cytotoxicity and cell death in a dose- and time-dependent manner in HCT-116 and LoVo cells, with less toxicity on non-cancer cells. Compared to MH, STH showed more effect at lower concentrations on HCT-116 and LoVo cells. In addition, both honeys increased intracellular reactive oxygen species (ROS) generation. In HCT-116 cells, STH and MH induced similar ROS production but in LoVo cells STH induced a higher percentage of ROS compared to MH. Our results indicate that STH and MH can induce cell growth inhibition and ROS generation in colon adenocarcinoma and metastatic cells, which could be due to the presence of phytochemicals with antioxidant properties. These preliminary results are interesting and suggest a potential chemopreventive action which could be useful for further studies in order to develop chemopreventive agents for colon cancer.

Strawberry-Tree Honey Induces Growth Inhibition of Human Colon Cancer Cells and Increases ROS Generation: A Comparison with Manuka Honey

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Sadia Afrin

2017-03-01

Full Text Available Honey is a natural product known to modulate several biological activities including cancer. The aim of the present study was to examine the phytochemical content and the antioxidant activity of Strawberry tree (Arbutus unedo honey (STH and its cytotoxic properties against human colon adenocarcinoma (HCT-116 and metastatic (LoVo cell lines in comparison with Manuka (Leptospermum scoparium honey (MH. Several unifloral STH and MH were analyzed for their phenolic, flavonoid, amino acid and protein contents, as well as their radical scavenging activities. STH from the Berchidda area showed the highest amount of phenolic, flavonoid, amino acid and protein content, and antioxidant capacity compared to MH. Both STH and MH induced cytotoxicity and cell death in a dose- and time-dependent manner in HCT-116 and LoVo cells, with less toxicity on non-cancer cells. Compared to MH, STH showed more effect at lower concentrations on HCT-116 and LoVo cells. In addition, both honeys increased intracellular reactive oxygen species (ROS generation. In HCT-116 cells, STH and MH induced similar ROS production but in LoVo cells STH induced a higher percentage of ROS compared to MH. Our results indicate that STH and MH can induce cell growth inhibition and ROS generation in colon adenocarcinoma and metastatic cells, which could be due to the presence of phytochemicals with antioxidant properties. These preliminary results are interesting and suggest a potential chemopreventive action which could be useful for further studies in order to develop chemopreventive agents for colon cancer.

Cell proliferation and ageing in mouse colon

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Hamilton, E.; Franks, L.M.

1980-01-01

Cell kinetic parameters in the descending colon of unirradiated mice, 3-30-months-old were compared with those in mice irradiated repeatedly from the age of 6 or 24 months. The latter animals were given 1250 rad local X-irradiation to the colon every 6 weeks. Dose-survival curves showed the colon crypts of 6 and 24-months-old mice were similarly radiosensitive. In unirradiated mice the number of crypts per colon section decreased significantly at 30 months, but no significant age-related changes were seen in crypt size or labelling index (LI). Cell proliferation returned to control levels within 6 weeks of each X-ray dose and remained at this level for 20 weeks after the final dose. Later, cell proliferation in the irradiated colon fell significantly below control. A total of 6 or 7 doses each of 1250 rad produced only 1 colon carcinoma amongst 50 mice kept until they died. (author)

Growth-inhibitory effects of a mineralized extract from the red marine algae, Lithothamnion calcareum, on Ca2+-sensitive and Ca2+-resistant human colon carcinoma cells

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Nadeem Aslam, Muhammad; Bhagavathula, Narasimharao; Paruchuri, Tejaswi; Hu, Xin; Chakrabarty, Subhas; Varani, James

2009-01-01

Proliferation and differentiation were assessed in a series of human colon carcinoma cell lines in response to a mineral-rich extract derived from the red marine algae, Lithothamnion calcareum. The extract contains 12% Ca2+, 1% Mg2+, and detectable amounts of 72 trace elements, but essentially no organic material. The red algae extract was as effective as inorganic Ca2+ alone in suppressing growth and inducing differentiation of colon carcinoma cells that are responsive to a physiological lev...

Prolonged sulforaphane treatment activates survival signaling in nontumorigenic NCM460 colon cells but apoptotic signaling in tumorigenic HCT116 colon cells.

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Zeng, Huawei; Trujillo, Olivia N; Moyer, Mary P; Botnen, James H

2011-01-01

Sulforaphane (SFN) is a naturally occurring chemopreventive agent; the induction of cell cycle arrest and apoptosis is a key mechanism by which SFN exerts its colon cancer prevention. However, little is known about the differential effects of SFN on colon cancer and normal cells. In this study, we demonstrated that SFN (15 μmol/L) exposure (72 h) inhibited cell proliferation by up to 95% in colon cancer cells (HCT116) and by 52% in normal colon mucosa-derived (NCM460) cells. Our data also showed that SFN exposure (5 and 10 μmol/L) led to the reduction of G1 phase cell distribution and an induction of apoptosis in HCT116 cells, but to a much lesser extent in NCM460 cells. Furthermore, the examination of mitogen-activated protein kinase (MAPK) signaling status revealed that SFN upregulated the phosphorylation of extracellular-regulated kinase 1/2 (ERK1/2) in NCM460 cells but not in HCT116 cells. In contrast, SFN enhanced the phosphorylation of stress-activated protein kinase (SAPK) and decreased cellular myelocytomatosis oncogene (c-Myc) expression in HCT116 cells but not NCM460 cells. Taken together, the activation of survival signaling in NCM460 cells and apoptotic signaling in HCT116 cells may play a critical role in SFN's stronger potential of inhibiting cell proliferation in colon cancer cells than in normal colon cells. Copyright © 2011, Taylor & Francis Group, LLC

A20 restricts wnt signaling in intestinal epithelial cells and suppresses colon carcinogenesis.

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Ling Shao

Full Text Available Colon carcinogenesis consists of a multistep process during which a series of genetic and epigenetic adaptations occur that lead to malignant transformation. Here, we have studied the role of A20 (also known as TNFAIP3, a ubiquitin-editing enzyme that restricts NFκB and cell death signaling, in intestinal homeostasis and tumorigenesis. We have found that A20 expression is consistently reduced in human colonic adenomas than in normal colonic tissues. To further investigate A20's potential roles in regulating colon carcinogenesis, we have generated mice lacking A20 specifically in intestinal epithelial cells and interbred these with mice harboring a mutation in the adenomatous polyposis coli gene (APC(min. While A20(FL/FL villin-Cre mice exhibit uninflamed intestines without polyps, A20(FL/FL villin-Cre APC(min/+ mice contain far greater numbers and larger colonic polyps than control APC(min mice. We find that A20 binds to the β-catenin destruction complex and restricts canonical wnt signaling by supporting ubiquitination and degradation of β-catenin in intestinal epithelial cells. Moreover, acute deletion of A20 from intestinal epithelial cells in vivo leads to enhanced expression of the β-catenin dependent genes cyclinD1 and c-myc, known promoters of colon cancer. Taken together, these findings demonstrate new roles for A20 in restricting β-catenin signaling and preventing colon tumorigenesis.

Colonic spirochetosis in animals and humans.

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Smith, James L

2005-07-01

Colonic spirochetosis is a disease caused by the gram-negative bacteria Brachyspira aalborgi and Brachyspira pilosicoli. B. pilosicoli induces disease in both humans and animals, whereas B. aalborgi affects only humans and higher primates. Symptoms in humans include diarrhea, rectal bleeding, and abdominal cramps. Colonic spirochetosis is common in third world countries; however, in developed countries, the disease is observed mainly in homosexual males. Terminally ill patients infected with Brachyspira are particularly at risk for developing spirochetemia. Diarrhea, poor growth performance, and decreased feed-to-gain efficiency is seen in pigs with colonic spirochetosis. The disease in chickens is characterized by delayed and/or reduced egg production, diarrhea, poor feed conversion, and retarded growth. Thus, colonic spirochetosis can represent a serious economic loss in the swine and poultry industries. The organisms are transmitted by the fecal-oral route, and several studies have demonstrated that human, primate, pig, dog, or bird strains of B. pilosicoli can be transmitted to pigs, chickens, and mice. B. pilosicoli may be a zoonotic pathogen, and although it has not been demonstrated, there is a possibility that both B. pilosicoli and B. aalborgi can be transferred to humans via contact with the feces of infected animals, meat from infected animals, or food contaminated by food handlers. Neither B. pilosicoli nor B. aalborgi has been well characterized in terms of basic cellular functions, pathogenicity, or genetics. Studies are needed to more thoroughly understand these Brachyspira species and their disease mechanisms.

Increased diacylglycerol kinase ζ expression in human metastatic colon cancer cells augments Rho GTPase activity and contributes to enhanced invasion

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Cai, Kun; Mulatz, Kirk; Ard, Ryan; Nguyen, Thanh; Gee, Stephen H

2014-01-01

Unraveling the signaling pathways responsible for the establishment of a metastatic phenotype in carcinoma cells is critically important for understanding the pathology of cancer. The acquisition of cell motility is a key property of metastatic tumor cells and is a prerequisite for invasion. Rho GTPases regulate actin cytoskeleton reorganization and the cellular responses required for cell motility and invasion. Diacylglycerol kinase ζ (DGKζ), an enzyme that phosphorylates diacylglycerol to yield phosphatidic acid, regulates the activity of the Rho GTPases Rac1 and RhoA. DGKζ mRNA is highly expressed in several different colon cancer cell lines, as well as in colon cancer tissue relative to normal colonic epithelium, and thus may contribute to the metastatic process. To investigate potential roles of DGKζ in cancer metastasis, a cellular, isogenic model of human colorectal cancer metastatic transition was used. DGKζ protein levels, Rac1 and RhoA activity, and PAK phosphorylation were measured in the non-metastatic SW480 adenocarcinoma cell line and its highly metastatic variant, the SW620 line. The effect of DGKζ silencing on Rho GTPase activity and invasion through Matrigel-coated Transwell inserts was studied in SW620 cells. Invasiveness was also measured in PC-3 prostate cancer and MDA-MB-231 breast cancer cells depleted of DGKζ. DGKζ protein levels were elevated approximately 3-fold in SW620 cells compared to SW480 cells. There was a concomitant increase in active Rac1 in SW620 cells, as well as substantial increases in the expression and phosphorylation of the Rac1 effector PAK1. Similarly, RhoA activity and expression were increased in SW620 cells. Knockdown of DGKζ expression in SW620 cells by shRNA-mediated silencing significantly reduced Rac1 and RhoA activity and attenuated the invasiveness of SW620 cells in vitro. DGKζ silencing in highly metastatic MDA-MB-231 breast cancer cells and PC-3 prostate cancer cells also significantly attenuated

Aspirin exerts high anti-cancer activity in PIK3CA-mutant colon cancer cells.

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Gu, Mancang; Nishihara, Reiko; Chen, Yang; Li, Wanwan; Shi, Yan; Masugi, Yohei; Hamada, Tsuyoshi; Kosumi, Keisuke; Liu, Li; da Silva, Annacarolina; Nowak, Jonathan A; Twombly, Tyler; Du, Chunxia; Koh, Hideo; Li, Wenbin; Meyerhardt, Jeffrey A; Wolpin, Brian M; Giannakis, Marios; Aguirre, Andrew J; Bass, Adam J; Drew, David A; Chan, Andrew T; Fuchs, Charles S; Qian, Zhi Rong; Ogino, Shuji

2017-10-20

Evidence suggests that nonsteroidal anti-inflammatory drug aspirin (acetylsalicylic acid) may improve patient survival in PIK3CA -mutant colorectal carcinoma, but not in PIK3CA -wild-type carcinoma. However, whether aspirin directly influences the viability of PIK3CA -mutant colon cancer cells is poorly understood. We conducted in vitro experiments to test our hypothesis that the anti-proliferative activity of aspirin might be stronger for PIK3CA -mutant colon cancer cells than for PIK3CA -wild-type colon cancer cells. We measured the anti-proliferative effect of aspirin at physiologic concentrations in seven PIK3CA -mutant and six PIK3CA -wild-type human colon cancer cell lines. After exposure to aspirin, the apoptotic index and cell cycle phase of colon cancer cells were assessed. In addition, the effect of aspirin was examined in parental SW48 cells and SW48 cell clones with individual knock-in PIK3CA mutations of either c.3140A>G (p.H1047R) or c.1633G>A (p.E545K). Aspirin induced greater dose-dependent loss of cell viability in PIK3CA -mutant cells than in PIK3CA -wild-type cells after treatment for 48 and 72 hours. Aspirin treatment also led to higher proportions of apoptotic cells and G0/G1 phase arrest in PIK3CA -mutant cells than in PIK3CA -wild-type cells. Aspirin treatment of isogenic SW48 cells carrying a PIK3CA mutation, either c.3140A>G (p.H1047R) or c.1633G>A (p. E545K), resulted in a more significant loss of cell viability compared to wild-type controls. Our findings indicate that aspirin causes cell cycle arrest, induces apoptosis, and leads to loss of cell viability more profoundly in PIK3CA -mutated colon cancer cells than in PIK3CA -wild-type colon cancer cells. These findings support the use of aspirin to treat patients with PIK3CA -mutant colon cancer.

Effects of silk sericin on the proliferation and apoptosis of colon cancer cells

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Waraporn Kaewkorn

2012-01-01

Full Text Available Sericin is a silk protein woven from silkworm cocoons (Bombyx mori. In animal model, sericin has been reported to have anti-tumoral action against colon cancer. The mechanisms underlying the activity of sericin against cancer cells are not fully understood. The present study investigated the effects of sericin on human colorectal cancer SW480 cells compared to normal colonic mucosal FHC cells. Since the size of the sericin protein may be important for its activity, two ranges of molecular weight were tested. Sericin was found to decrease SW480 and FHC cell viability. The small sericin had higher anti-proliferative effects than that of the large sericin in both cell types. Increased apoptosis of SW480 cells is associated with increased caspase-3 activity and decreased Bcl-2 expression. The anti-proliferative effect of sericin was accompanied by cell cycle arrest at the S phase. Thus, sericin reduced SW480 cell viability by inducing cell apoptosis via caspase-3 activation and down-regulation of Bcl-2 expression. The present study provides scientific data that support the protective effect of silk sericin against cancer cells of the colon and suggests that this protein may have significant health benefits and could potentially be developed as a dietary supplement for colon cancer prevention.

The interplay between GRP78 expression and Akt activation in human colon cancer cells under celecoxib treatment.

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Tian, Shaobo; Chang, Weilong; Du, Hansong; Bai, Jie; Sun, Zhenhai; Zhang, Qing; Wang, Hui; Zhu, Guangsheng; Tao, Kaixiong; Long, Yueping

2015-10-01

It has been reported previously that celecoxib shows antitumor effects in many types of cancers. Here, we detected its effects on DLD-1 and SW480 (two human colon cancer cell lines) and investigated the dynamic relationship between the 78-kDa glucose-regulatory protein (GRP78) and the phosphoinositide 3-kinase (PI3K)/Akt pathway. Gene expression was detected by real-time PCR and western blot analysis; the cytotoxicity was determined by the MTT assay and flow cytometry. First, the results showed that celecoxib induced cytotoxicity in a dose-dependent and time-dependent manner. Furthermore, we found the celecoxib-triggered unfolded protein response and the bidirectional regulation of Akt activation in both cell lines. Inhibiting the Akt activation by the PI3K inhibitor LY294002 markedly enhanced GRP78 expression. Besides, silencing the GRP78 expression regulated Akt activation in a time-dependent manner and increased the induction of the C/EBP homologous protein (CHOP) as well as considerably promoted celecoxib-induced apoptosis. In conclusion, these findings provide evidence that under the celecoxib treatment, GRP78 plays a protective role by modulating Akt activation and abrogating CHOP expression. However, Akt activation can provide a feedback loop to inhibit GRP78 expression. These studies can lead to novel therapeutic strategies for human colon cancer.

Human colon tissue in organ culture: calcium and multi-mineral-induced mucosal differentiation.

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Dame, Michael K; Veerapaneni, Indiradevi; Bhagavathula, Narasimharao; Naik, Madhav; Varani, James

2011-01-01

We have recently shown that a multi-mineral extract from the marine red algae, Lithothamnion calcareum, suppresses colon polyp formation and inflammation in mice. In the present study, we used intact human colon tissue in organ culture to compare responses initiated by Ca(2+) supplementation versus the multi-mineral extract. Normal human colon tissue was treated for 2 d in culture with various concentrations of calcium or the mineral-rich extract. The tissue was then prepared for histology/immunohistochemistry, and the culture supernatants were assayed for levels of type I procollagen and type I collagen. At higher Ca(2+) concentrations or with the mineral-rich extract, proliferation of epithelial cells at the base and walls of the mucosal crypts was suppressed, as visualized by reduced Ki67 staining. E-cadherin, a marker of differentiation, was more strongly expressed at the upper third of the crypt and at the luminal surface. Treatment with Ca(2+) or with the multi-mineral extract influenced collagen turnover, with decreased procollagen and increased type I collagen. These data suggest that calcium or mineral-rich extract has the capacity to (1) promote differentiation in human colon tissue in organ culture and (2) modulate stromal function as assessed by increased levels of type I collagen. Taken together, these data suggest that human colon tissue in organ culture (supporting in vivo finding in mice) will provide a valuable model for the preclinical assessment of agents that regulate growth and differentiation in the colonic mucosa.

Methanolic extract of white asparagus shoots activates TRAIL apoptotic death pathway in human cancer cells and inhibits colon carcinogenesis in a preclinical model

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BOUSSEROUEL, SOUAD; LE GRANDOIS, JULIE; GOSSÉ, FRANCINE; WERNER, DALAL; BARTH, STEPHAN W.; MARCHIONI, ERIC; MARESCAUX, JACQUES; RAUL, FRANCIS

2013-01-01

Shoots of white asparagus are a popular vegetable dish, known to be rich in many bioactive phytochemicals reported to possess antioxidant, and anti-inflammatory and antitumor activities. We evaluated the anticancer mechanisms of a methanolic extract of Asparagus officinalis L. shoots (Asp) on human colon carcinoma cells (SW480) and their derived metastatic cells (SW620), and Asp chemopreventive properties were also assessed in a model of colon carcinogenesis. SW480 and SW620 cell proliferation was inhibited by 80% after exposure to Asp (80 μg/ml). We demonstrated that Asp induced cell death through the activation of TRAIL DR4/DR5 death receptors leading to the activation of caspase-8 and caspase-3 and to cell apoptosis. By specific blocking agents of DR4/DR5 receptors we were able to prevent Asp-triggered cell death confirming the key role of DR4/DR5 receptors. We found also that Asp (80 μg/ml) was able to potentiate the effects of the cytokine TRAIL on cell death even in the TRAIL-resistant metastatic SW620 cells. Colon carcinogenesis was initiated in Wistar rats by intraperitoneal injections of azoxymethane (AOM), once a week for two weeks. One week after (post-initiation) rats received daily Asp (0.01%, 14 mg/kg body weight) in drinking water. After 7 weeks of Asp-treatment the colon of rats exhibited a 50% reduction of the number of preneoplastic lesions (aberrant crypt foci). In addition Asp induced inhibition of several pro-inflammatory mediators, in association with an increased expression of host-defense mediators. In the colonic mucosa of Asp-treated rats we also confirmed the pro-apoptotic effects observed in vitro including the activation of the TRAIL death-receptor signaling pathway. Taken together, our data highlight the chemopreventive effects of Asp on colon carcinogenesis and its ability to promote normal cellular homeostasis. PMID:23754197

Integrin α6Bβ4 inhibits colon cancer cell proliferation and c-Myc activity

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Dydensborg, Anders Bondo; Teller, Inga C; Groulx, Jean-François; Basora, Nuria; Paré, Fréderic; Herring, Elizabeth; Gauthier, Rémy; Jean, Dominique; Beaulieu, Jean-François

2009-01-01

Integrins are known to be important contributors to cancer progression. We have previously shown that the integrin β4 subunit is up-regulated in primary colon cancer. Its partner, the integrin α6 subunit, exists as two different mRNA splice variants, α6A and α6B, that differ in their cytoplasmic domains but evidence for distinct biological functions of these α6 splice variants is still lacking. In this work, we first analyzed the expression of integrin α6A and α6B at the protein and transcript levels in normal human colonic cells as well as colorectal adenocarcinoma cells from both primary tumors and established cell lines. Then, using forced expression experiments, we investigated the effect of α6A and α6B on the regulation of cell proliferation in a colon cancer cell line. Using variant-specific antibodies, we observed that α6A and α6B are differentially expressed both within the normal adult colonic epithelium and between normal and diseased colonic tissues. Proliferative cells located in the lower half of the glands were found to predominantly express α6A, while the differentiated and quiescent colonocytes in the upper half of the glands and surface epithelium expressed α6B. A relative decrease of α6B expression was also identified in primary colon tumors and adenocarcinoma cell lines suggesting that the α6A/α6B ratios may be linked to the proliferative status of colonic cells. Additional studies in colon cancer cells showed that experimentally restoring the α6A/α6B balance in favor of α6B caused a decrease in cellular S-phase entry and repressed the activity of c-Myc. The findings that the α6Bβ4 integrin is expressed in quiescent normal colonic cells and is significantly down-regulated in colon cancer cells relative to its α6Aβ4 counterpart are consistent with the anti-proliferative influence and inhibitory effect on c-Myc activity identified for this α6Bβ4 integrin. Taken together, these findings point out the importance of integrin

miR-409-3p sensitizes colon cancer cells to oxaliplatin by inhibiting Beclin-1-mediated autophagy.

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Tan, Shifan; Shi, Huijuan; Ba, Mingchen; Lin, Shengqv; Tang, Hongsheng; Zeng, Xiaoqi; Zhang, Xiangliang

2016-04-01

The chemoresistance of colon cancer cells limits the efficacy of chemotherapy. miR-409-3p has been shown to be downregulated in various types of cancer. In the present study, we examined the role of miR-409-3p in colon cancer as well as the effects of miR‑409-3p on the sensitivity of colon cancer cells to oxaliplatin. The expression of miR-409 was significantly downregulated in the human colon cancer cell lines compared with the normal colon epithelial cells. Importantly, the miR-409-3p expression levels were lower in human colon cancer patient samples than in normal colon tissues. Moreover, we observed a negative correlation between the miR‑409-3p levels and resistance to oxaliplatin: the oxaliplatin-resistant colon cancer cells exhibited significantly downregulated miR‑409-3p levels, but higher autophagic activity than the oxaliplatin-sensitive cells. Using bioinformatics analysis, we predicted that miR‑409-3p miRNA binds to the key autophagy gene encoding Beclin-1. Our findings indicated that the overexpression of miR‑409-3p inhibited Beclin-1 expression and autophagic activity by binding to the 3'-untranslated region of Beclin-1 mRNA. In addition, the overexpression of miR‑409-3p enhanced the chemosensitivity of the oxaliplatin-sensitive and oxaliplatin-resistant colon cancer cells. The restoration of Beclin-1 abrogated these effects of miR‑409-3p. In a xenograft model using nude mice, we examined the effects of miR‑409-3p on tumor growth during chemotherapy. miR‑409-3p overexpression sensitized the tumor to chemotherapy, while inhibiting chemotherapy-induced autophagy in a manner dependent on Beclin-1. The findings of our study suggest that miR-409-3p is capable of enhancing the chemosensitivity of colon cancer cells by inhibiting Beclin-1-mediated autophagy.

3D-fibroblast tissues constructed by a cell-coat technology enhance tight-junction formation of human colon epithelial cells.

Science.gov (United States)

Matsusaki, Michiya; Hikimoto, Daichi; Nishiguchi, Akihiro; Kadowaki, Koji; Ohura, Kayoko; Imai, Teruko; Akashi, Mitsuru

2015-02-13

Caco-2, human colon carcinoma cell line, has been widely used as a model system for intestinal epithelial permeability because Caco-2 cells express tight-junctions, microvilli, and a number of enzymes and transporters characteristic of enterocytes. However, the functional differentiation and polarization of Caco-2 cells to express sufficient tight-junctions (a barrier) usually takes over 21 days in culture. This may be due to the cell culture environment, for example inflammation induced by plastic petri dishes. Three-dimensional (3D) sufficient cell microenvironments similar to in vivo natural conditions (proteins and cells), will promote rapid differentiation and higher functional expression of tight junctions. Herein we report for the first time an enhancement in tight-junction formation by 3D-cultures of Caco-2 cells on monolayered (1L) and eight layered (8L) normal human dermal fibroblasts (NHDF). Trans epithelial electric resistance (TEER) of Caco-2 cells was enhanced in the 3D-cultures, especially 8L-NHDF tissues, depending on culture times and only 10 days was enough to reach the same TEER value of Caco-2 monolayers after a 21 day incubation. Relative mRNA expression of tight-junction proteins of Caco-2 cells on 3D-cultures showed higher values than those in monolayer structures. Transporter gene expression patterns of Caco-2 cells on 3D-constructs were almost the same as those of Caco-2 monolayers, suggesting that there was no effect of 3D-cultures on transporter protein expression. The expression correlation between carboxylesterase 1 and 2 in 3D-cultures represented similar trends with human small intestines. The results of this study clearly represent a valuable application of 3D-Caco-2 tissues for pharmaceutical applications. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of cyclic-nucleotide derivatives on the growth of human colonic carcinoma xenografts and on cell production in the rat colonic crypt epithelium.

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Tutton, P J; Barkla, D H

1981-08-01

Previous studies have shown that various amine hormones are able to influence the growth rate of human colorectal carcinomas propagated as xenografts in immune-deprived mice, and it is now well known that the effects of many amine and other hormones are mediated by cyclic nucleotides, acting as second messengers within cells. In the present study the influence of various derivatives of cyclic adenosine monophosphate and cyclic guanosine monophosphate on the growth of two different lines of colorectal cancer growing in immune-deprived mice, and on the cell production rate in the colonic crypt epithelium of the rat, was assessed. Growth of each tumour line, as well as crypt-cell production, was suppressed by treatment wit N6O2' dibutyryl and N6 monobutyryl derivatives of cyclic adenosine monophosphate. Dibutyryl cyclic guanosine monophosphate, on the other hand, was found to promote the growth of Tumour HXK4 and to promote crypt cell production, but to have no significant effect on Tumour HXM2.

Biosynthesis of human colonic mucin: Muc2 is the prominent secretory mucin

NARCIS (Netherlands)

Tytgat, K. M.; Büller, H. A.; Opdam, F. J.; Kim, Y. S.; Einerhand, A. W.; Dekker, J.

1994-01-01

Human colonic epithelium produces large amounts of mucin. The aim of this study was to examine mucin biosynthesis in the human colon. Human colonic mucin was isolated using CsCl density gradients, and polyclonal antiserum was raised. Biosynthesis of colonic mucins was studied by labeling colonic

Comparison of intracellular accumulation and cytotoxicity of free mTHPC and mTHPC-loaded PLGA nanoparticles in human colon carcinoma cells

International Nuclear Information System (INIS)

Loew, Karin; Wagner, Sylvia; Briesen, Hagen von; Knobloch, Thomas; Wiehe, Arno; Engel, Andrea; Langer, Klaus

2011-01-01

The second generation photosensitizer mTHPC was approved by the European Medicines Agency (EMA) for the palliative treatment of advanced head and neck cancer in October 2001. It is known that mTHPC possesses a significant phototoxicity against a variety of human cancer cells in vitro but also exhibits dark toxicity and can cause adverse effects (especially skin photosensitization). Due to its poor water solubility, the administration of hydrophobic photosensitizer still presents several difficulties. To overcome the administration problems, the use of nanoparticles as drug carrier systems is much investigated. Nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) have been extensively studied as delivery systems into tumours due to their biocompatibility and biodegradability. The goal of this study was the comparison of free mTHPC and mTHPC-loaded PLGA nanoparticles concerning cytotoxicity and intracellular accumulation in human colon carcinoma cells (HT29). The nanoparticles delivered the photosensitizer to the colon carcinoma cells and enabled drug release without losing its activity. The cytotoxicity assays showed a time- and concentration-dependent decrease in cell proliferation and viability after illumination. However, first and foremost mTHPC lost its dark toxic effects using the PLGA nanoparticles as a drug carrier system. Therefore, PLGA nanoparticles are a promising drug carrier system for the hydrophobic photosensitizer mTHPC.

Comparison of intracellular accumulation and cytotoxicity of free mTHPC and mTHPC-loaded PLGA nanoparticles in human colon carcinoma cells

Energy Technology Data Exchange (ETDEWEB)

Loew, Karin; Wagner, Sylvia; Briesen, Hagen von [Fraunhofer-Institute for Biomedical Engineering, D-66386 Strasse Ingbert (Germany); Knobloch, Thomas [Institute of Pharmaceutical Technology, Biocenter of Goethe-University, D-60438 Frankfurt (Germany); Wiehe, Arno [Biolitec AG, D-07745 Jena (Germany); Engel, Andrea; Langer, Klaus, E-mail: hagen.briesen@ibmt.fraunhofer.de [Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster, D-48149 Muenster (Germany)

2011-06-17

The second generation photosensitizer mTHPC was approved by the European Medicines Agency (EMA) for the palliative treatment of advanced head and neck cancer in October 2001. It is known that mTHPC possesses a significant phototoxicity against a variety of human cancer cells in vitro but also exhibits dark toxicity and can cause adverse effects (especially skin photosensitization). Due to its poor water solubility, the administration of hydrophobic photosensitizer still presents several difficulties. To overcome the administration problems, the use of nanoparticles as drug carrier systems is much investigated. Nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) have been extensively studied as delivery systems into tumours due to their biocompatibility and biodegradability. The goal of this study was the comparison of free mTHPC and mTHPC-loaded PLGA nanoparticles concerning cytotoxicity and intracellular accumulation in human colon carcinoma cells (HT29). The nanoparticles delivered the photosensitizer to the colon carcinoma cells and enabled drug release without losing its activity. The cytotoxicity assays showed a time- and concentration-dependent decrease in cell proliferation and viability after illumination. However, first and foremost mTHPC lost its dark toxic effects using the PLGA nanoparticles as a drug carrier system. Therefore, PLGA nanoparticles are a promising drug carrier system for the hydrophobic photosensitizer mTHPC.

Generation of an inducible colon-specific Cre enzyme mouse line for colon cancer research.

Science.gov (United States)

Tetteh, Paul W; Kretzschmar, Kai; Begthel, Harry; van den Born, Maaike; Korving, Jeroen; Morsink, Folkert; Farin, Henner; van Es, Johan H; Offerhaus, G Johan A; Clevers, Hans

2016-10-18

Current mouse models for colorectal cancer often differ significantly from human colon cancer, being largely restricted to the small intestine. Here, we aim to develop a colon-specific inducible mouse model that can faithfully recapitulate human colon cancer initiation and progression. Carbonic anhydrase I (Car1) is a gene expressed uniquely in colonic epithelial cells. We generated a colon-specific inducible Car1 CreER knock-in (KI) mouse with broad Cre activity in epithelial cells of the proximal colon and cecum. Deletion of the tumor suppressor gene Apc using the Car1 CreER KI caused tumor formation in the cecum but did not yield adenomas in the proximal colon. Mutation of both Apc and Kras yielded microadenomas in both the cecum and the proximal colon, which progressed to macroadenomas with significant morbidity. Aggressive carcinomas with some invasion into lymph nodes developed upon combined induction of oncogenic mutations of Apc, Kras, p53, and Smad4 Importantly, no adenomas were observed in the small intestine. Additionally, we observed tumors from differentiated Car1-expressing cells with Apc/Kras mutations, suggesting that a top-down model of intestinal tumorigenesis can occur with multiple mutations. Our results establish the Car1 CreER KI as a valuable mouse model to study colon-specific tumorigenesis and metastasis as well as cancer-cell-of-origin questions.

High susceptibility of metastatic cells derived from human prostate and colon cancer cells to TRAIL and sensitization of TRAIL-insensitive primary cells to TRAIL by 4,5-dimethoxy-2-nitrobenzaldehyde

Directory of Open Access Journals (Sweden)

Lee Jae-Won

2011-04-01

Full Text Available Abstract Background Tumor recurrence and metastasis develop as a result of tumors' acquisition of anti-apoptotic mechanisms and therefore, it is necessary to develop novel effective therapeutics against metastatic cancers. In this study, we showed the differential TRAIL responsiveness of human prostate adenocarcinoma PC3 and human colon carcinoma KM12 cells and their respective highly metastatic PC3-MM2 and KM12L4A sublines and investigated the mechanism underlying high susceptibility of human metastatic cancer cells to TRAIL. Results PC3-MM2 and KM12L4A cells with high level of c-Myc and DNA-PKcs were more susceptible to TRAIL than their poorly metastatic primary PC3 and KM12 cells, which was associated with down-regulation of c-FLIPL/S and Mcl-1 and up-regulation of the TRAIL receptor DR5 but not DR4 in both metastatic cells. Moreover, high susceptibility of these metastatic cells to TRAIL was resulted from TRAIL-induced potent activation of caspase-8, -9, and -3 in comparison with their primary cells, which led to cleavage and down-regulation of DNA-PKcs. Knockdown of c-Myc gene in TRAIL-treated PC3-MM2 cells prevented the increase of DR5 cell surface expression, caspase activation and DNA-PKcs cleavage and attenuated the apoptotic effects of TRAIL. Moreover, the suppression of DNA-PKcs level with siRNA in the cells induced the up-regulation of DR5 and active caspase-8, -9, and -3. We also found that 4,5-dimethoxy-2-nitrobenzaldehyde (DMNB, a specific inhibitor of DNA-PK, potentiated TRAIL-induced cytotoxicity and apoptosis in relatively TRAIL-insensitive PC3 and KM12 cells and therefore functioned as a TRAIL sensitizer. Conclusion This study showed the positive relationship between c-Myc expression in highly metastatic human prostate and colon cancer cells and susceptibility to TRAIL-induced apoptosis and therefore indicated that TRAIL might be used as an effective therapeutic modality for advanced metastatic cancers overexpressing c-Myc and

Matrix Stiffness Corresponding to Strictured Bowel Induces a Fibrogenic Response in Human Colonic Fibroblasts

Science.gov (United States)

Johnson, Laura A.; Rodansky, Eva S.; Sauder, Kay L.; Horowitz, Jeffrey C.; Mih, Justin D.; Tschumperlin, Daniel J.; Higgins, Peter D.

2013-01-01

Background Crohn’s disease is characterized by repeated cycles of inflammation and mucosal healing which ultimately progress to intestinal fibrosis. This inexorable progression towards fibrosis suggests that fibrosis becomes inflammation-independent and auto-propagative. We hypothesized that matrix stiffness regulates this auto-propagation of intestinal fibrosis. Methods The stiffness of fresh ex vivo samples from normal human small intestine, Crohn’s disease strictures, and the unaffected margin were measured with a microelastometer. Normal human colonic fibroblasts were cultured on physiologically normal or pathologically stiff matrices corresponding to the physiological stiffness of normal or fibrotic bowel. Cellular response was assayed for changes in cell morphology, α-smooth muscle actin (αSMA) staining, and gene expression. Results Microelastometer measurements revealed a significant increase in colonic tissue stiffness between normal human colon and Crohn’s strictures as well as between the stricture and adjacent tissue margin. In Ccd-18co cells grown on stiff matrices corresponding to Crohn’s strictures, cellular proliferation increased. Pathologic stiffness induced a marked change in cell morphology and increased αSMA protein expression. Growth on a stiff matrix induced fibrogenic gene expression, decreased matrix metalloproteinase and pro-inflammatory gene expression, and was associated with nuclear localization of the transcriptional cofactor MRTF-A. Conclusions Matrix stiffness, representative of the pathological stiffness of Crohn’s strictures, activates human colonic fibroblasts to a fibrogenic phenotype. Matrix stiffness affects multiple pathways suggesting the mechanical properties of the cellular environment are critical to fibroblast function and may contribute to autopropagation of intestinal fibrosis in the absence of inflammation, thereby contributing to the intractable intestinal fibrosis characteristic of Crohn’s disease. PMID

Negligible colon cancer risk from food-borne acrylamide exposure in male F344 rats and nude (nu/nu mice-bearing human colon tumor xenografts.

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Jayadev Raju

Full Text Available Acrylamide, a possible human carcinogen, is formed in certain carbohydrate-rich foods processed at high temperature. We evaluated if dietary acrylamide, at doses (0.5, 1.0 or 2.0 mg/kg diet reflecting upper levels found in human foods, modulated colon tumorigenesis in two rodent models. Male F344 rats were randomized to receive diets without (control or with acrylamide. 2-weeks later, rats in each group received two weekly subcutaneous injections of either azoxymethane (AOM or saline, and were killed 20 weeks post-injections; colons were assessed for tumors. Male athymic nude (nu/nu mice bearing HT-29 human colon adenocarcinoma cells-derived tumor xenografts received diets without (control or with acrylamide; tumor growth was monitored and mice were killed 4 weeks later. In the F344 rat study, no tumors were found in the colons of the saline-injected rats. However, the colon tumor incidence was 54.2% and 66.7% in the control and the 2 mg/kg acrylamide-treated AOM-injected groups, respectively. While tumor multiplicity was similar across all diet groups, tumor size and burden were higher in the 2 mg/kg acrylamide group compared to the AOM control. These results suggest that acrylamide by itself is not a "complete carcinogen", but acts as a "co-carcinogen" by exacerbating the effects of AOM. The nude mouse study indicated no differences in the growth of human colon tumor xenografts between acrylamide-treated and control mice, suggesting that acrylamide does not aid in the progression of established tumors. Hence, food-borne acrylamide at levels comparable to those found in human foods is neither an independent carcinogen nor a tumor promoter in the colon. However, our results characterize a potential hazard of acrylamide as a colon co-carcinogen in association with known and possibly other environmental tumor initiators/promoters.

Butyrate Inhibits Cancerous HCT116 Colon Cell Proliferation but to a Lesser Extent in Noncancerous NCM460 Colon Cells.

Science.gov (United States)

Zeng, Huawei; Taussig, David P; Cheng, Wen-Hsing; Johnson, LuAnn K; Hakkak, Reza

2017-01-01

Butyrate, an intestinal microbiota metabolite of dietary fiber, exhibits chemoprevention effects on colon cancer development. However, the mechanistic action of butyrate remains to be determined. We hypothesize that butyrate inhibits cancerous cell proliferation but to a lesser extent in noncancerous cells through regulating apoptosis and cellular-signaling pathways. We tested this hypothesis by exposing cancerous HCT116 or non-cancerous NCM460 colon cells to physiologically relevant doses of butyrate. Cellular responses to butyrate were characterized by Western analysis, fluorescent microscopy, acetylation, and DNA fragmentation analyses. Butyrate inhibited cell proliferation, and led to an induction of apoptosis, genomic DNA fragmentation in HCT116 cells, but to a lesser extent in NCM460 cells. Although butyrate increased H3 histone deacetylation and p21 tumor suppressor expression in both cell types, p21 protein level was greater with intense expression around the nuclei in HCT116 cells when compared with that in NCM460 cells. Furthermore, butyrate treatment increased the phosphorylation of extracellular-regulated kinase 1/2 (p-ERK1/2), a survival signal, in NCM460 cells while it decreased p-ERK1/2 in HCT116 cells. Taken together, the activation of survival signaling in NCM460 cells and apoptotic potential in HCT116 cells may confer the increased sensitivity of cancerous colon cells to butyrate in comparison with noncancerous colon cells.

Study on therapy of 188Re labelled stannic sulfur suspension in nude mice bearing human colon tumor

International Nuclear Information System (INIS)

Li Huiyuan; Wu Yuanfang; Dong Mo

2003-01-01

The effect of therapy, tissue distribution and stability are studied in nude mice bearing human colon tumor after injections of 188 Re labelled stannic sulfur suspension. The tissues are observed with electric microscope. The results show that 188 Re labelled stannic sulfur suspension is stabilized in the tumor and its inhibitive effects on human colon tumor cells are obvious. 188 Re labelled stannic sulfur suspension is a potential radiopharmaceuticals for therapy of human tumor

The novel HDAC inhibitor AR-42-induced anti-colon cancer cell activity is associated with ceramide production

International Nuclear Information System (INIS)

Xu, Weihong; Xu, Bin; Yao, Yiting; Yu, Xiaoling; Shen, Jie

2015-01-01

In the current study, we investigated the potential activity of AR-42, a novel histone deacetylase (HDAC) inhibitor, against colon cancer cells. Our in vitro results showed that AR-42 induced ceramide production, exerted potent anti-proliferative and pro-apoptotic activities in established (SW-620 and HCT-116 lines) and primary human colon cancer cells. Exogenously-added sphingosine 1-phosphate (S1P) suppressed AR-42-induced activity, yet a cell-permeable ceramide (C4) facilitated AR-42-induced cytotoxicity against colon cancer cells. In addition, AR-42-induced ceramide production and anti-colon cancer cell activity were inhibited by the ceramide synthase inhibitor fumonisin B1, but were exacerbated by PDMP, which is a ceramide glucosylation inhibitor. In vivo, oral administration of a single dose of AR-42 dramatically inhibited SW-620 xenograft growth in severe combined immunodeficient (SCID) mice, without inducing overt toxicities. Together, these results show that AR-42 dramatically inhibits colon cancer cell proliferation in vitro and in vivo, and ceramide production might be the key mechanism responsible for its actions. - Highlights: • AR-42 is anti-proliferative against primary/established colon cancer cells. • AR-42 induces significant apoptotic death in primary/established colon cancer cells. • Ceramide production mediates AR-42-induced cytotoxicity in colon cancer cells. • AR-42 oral administration potently inhibits SW-620 xenograft growth in SCID mice

The novel HDAC inhibitor AR-42-induced anti-colon cancer cell activity is associated with ceramide production

Energy Technology Data Exchange (ETDEWEB)

Xu, Weihong; Xu, Bin; Yao, Yiting; Yu, Xiaoling [Department of Clinical Laboratory, Tongren Hospital, Shanghai (China); Shen, Jie, E-mail: tongrensj163@163.com [Department of Administrative, Tongren Hospital, No. 786 Yuyuan Road, Changning District, Shanghai (China)

2015-08-07

In the current study, we investigated the potential activity of AR-42, a novel histone deacetylase (HDAC) inhibitor, against colon cancer cells. Our in vitro results showed that AR-42 induced ceramide production, exerted potent anti-proliferative and pro-apoptotic activities in established (SW-620 and HCT-116 lines) and primary human colon cancer cells. Exogenously-added sphingosine 1-phosphate (S1P) suppressed AR-42-induced activity, yet a cell-permeable ceramide (C4) facilitated AR-42-induced cytotoxicity against colon cancer cells. In addition, AR-42-induced ceramide production and anti-colon cancer cell activity were inhibited by the ceramide synthase inhibitor fumonisin B1, but were exacerbated by PDMP, which is a ceramide glucosylation inhibitor. In vivo, oral administration of a single dose of AR-42 dramatically inhibited SW-620 xenograft growth in severe combined immunodeficient (SCID) mice, without inducing overt toxicities. Together, these results show that AR-42 dramatically inhibits colon cancer cell proliferation in vitro and in vivo, and ceramide production might be the key mechanism responsible for its actions. - Highlights: • AR-42 is anti-proliferative against primary/established colon cancer cells. • AR-42 induces significant apoptotic death in primary/established colon cancer cells. • Ceramide production mediates AR-42-induced cytotoxicity in colon cancer cells. • AR-42 oral administration potently inhibits SW-620 xenograft growth in SCID mice.

Displayed correlation between gene expression profiles and submicroscopic alterations in response to cetuximab, gefitinib and EGF in human colon cancer cell lines

Energy Technology Data Exchange (ETDEWEB)

Solmi, Rossella [Dipartimento di Istologia, Embriologia e Biologia Applicata, Università di Bologna, Via Belmeloro 8, 40126 Bologna (Italy); Montroni, Isacco [Dipartimento Emergenza/Urgenza, Chirurgia Generale e dei Trapianti, Università di Bologna, Bologna (Italy); Mattei, Gabriella [Dipartimento di Istologia, Embriologia e Biologia Applicata, Università di Bologna, Via Belmeloro 8, 40126 Bologna (Italy); Taffurelli, Mario [Dipartimento Emergenza/Urgenza, Chirurgia Generale e dei Trapianti, Università di Bologna, Bologna (Italy); Santini, Donatella [Dipartimento di Patologia, Università di Bologna, Bologna (Italy); Pezzetti, Furio [Dipartimento di Istologia, Embriologia e Biologia Applicata, Università di Bologna, Via Belmeloro 8, 40126 Bologna (Italy); Ruggeri, Alessandro [Dipartimento di Scienze Anatomiche Umane e Fisiopatologia dell' Apparato Locomotore, Università di Bologna, Bologna (Italy); Castellani, Gastone [Centro Interdipartimentale L. Galvani, Università di Bologna, Bologna (Italy); DIMORFIPA, Università di Bologna, Bologna (Italy); Guidotti, Lia [Dipartimento di Istologia, Embriologia e Biologia Applicata, Università di Bologna, Via Belmeloro 8, 40126 Bologna (Italy); Coppola, Domenico [H. Lee Moffit Cancer Center and Research Institute, University of South Florida, Tampa, FL (United States); Strippoli, Pierluigi; Lauriola, Mattia [Dipartimento di Istologia, Embriologia e Biologia Applicata, Università di Bologna, Via Belmeloro 8, 40126 Bologna (Italy); Francesconi, Mirko [Centro Interdipartimentale L. Galvani, Università di Bologna, Bologna (Italy); DIMORFIPA, Università di Bologna, Bologna (Italy); Martini, Désirée [Dipartimento di Scienze Anatomiche Umane e Fisiopatologia dell' Apparato Locomotore, Università di Bologna, Bologna (Italy); Voltattorni, Manuela [Laboratori di Biotecnologie, Via Beverara 123, Bologna (Italy); Ceccarelli, Claudio [Dipartimento di Patologia, Università di Bologna, Bologna (Italy); Ugolini, Giampaolo; Rosati, Giancarlo; Zanotti, Simone [Dipartimento Emergenza/Urgenza, Chirurgia Generale e dei Trapianti, Università di Bologna, Bologna (Italy)

2008-08-08

EGFR is frequently overexpressed in colon cancer. We characterized HT-29 and Caco-2, human colon cancer cell lines, untreated and treated with cetuximab or gefitinib alone and in combination with EGF. Cell growth was determined using a variation on the MTT assay. Cell-cycle analysis was conducted by flow cytometry. Immunohistochemistry was performed to evaluate EGFR expression and scanning electron microscopy (SEM) evidenced the ultrastructural morphology. Gene expression profiling was performed using hybridization of the microarray Ocimum Pan Human 40 K array A. Caco-2 and HT-29 were respectively 66.25 and 59.24 % in G0/G1. They maintained this level of cell cycle distribution after treatment, suggesting a predominantly differentiated state. Treatment of Caco-2 with EGF or the two EGFR inhibitors produced a significant reduction in their viability. SEM clearly showed morphological cellular transformations in the direction of cellular death in both cell lines treated with EGFR inhibitors. HT-29 and Caco-2 displayed an important reduction of the microvilli (which also lose their erect position in Caco-2), possibly invalidating microvilli absorption function. HT-29 treated with cetuximab lost their boundary contacts and showed filipodi; when treated with gefitinib, they showed some vesicles: generally membrane reshaping is evident. Both cell lines showed a similar behavior in terms of on/off switched genes upon treatment with cetuximab. The gefitinib global gene expression pattern was different for the 2 cell lines; gefitinib treatment induced more changes, but directly correlated with EGF treatment. In cetuximab or gefitinib plus EGF treatments there was possible summation of the morphological effects: cells seemed more weakly affected by the transformation towards apoptosis. The genes appeared to be less stimulated than for single drug cases. This is the first study to have systematically investigated the effect of cetuximab or gefitinib, alone and in combination

Displayed correlation between gene expression profiles and submicroscopic alterations in response to cetuximab, gefitinib and EGF in human colon cancer cell lines

Directory of Open Access Journals (Sweden)

Pezzetti Furio

2008-08-01

Full Text Available Abstract Background EGFR is frequently overexpressed in colon cancer. We characterized HT-29 and Caco-2, human colon cancer cell lines, untreated and treated with cetuximab or gefitinib alone and in combination with EGF. Methods Cell growth was determined using a variation on the MTT assay. Cell-cycle analysis was conducted by flow cytometry. Immunohistochemistry was performed to evaluate EGFR expression and scanning electron microscopy (SEM evidenced the ultrastructural morphology. Gene expression profiling was performed using hybridization of the microarray Ocimum Pan Human 40 K array A. Results Caco-2 and HT-29 were respectively 66.25 and 59.24 % in G0/G1. They maintained this level of cell cycle distribution after treatment, suggesting a predominantly differentiated state. Treatment of Caco-2 with EGF or the two EGFR inhibitors produced a significant reduction in their viability. SEM clearly showed morphological cellular transformations in the direction of cellular death in both cell lines treated with EGFR inhibitors. HT-29 and Caco-2 displayed an important reduction of the microvilli (which also lose their erect position in Caco-2, possibly invalidating microvilli absorption function. HT-29 treated with cetuximab lost their boundary contacts and showed filipodi; when treated with gefitinib, they showed some vesicles: generally membrane reshaping is evident. Both cell lines showed a similar behavior in terms of on/off switched genes upon treatment with cetuximab. The gefitinib global gene expression pattern was different for the 2 cell lines; gefitinib treatment induced more changes, but directly correlated with EGF treatment. In cetuximab or gefitinib plus EGF treatments there was possible summation of the morphological effects: cells seemed more weakly affected by the transformation towards apoptosis. The genes appeared to be less stimulated than for single drug cases. Conclusion This is the first study to have systematically investigated

Displayed correlation between gene expression profiles and submicroscopic alterations in response to cetuximab, gefitinib and EGF in human colon cancer cell lines

International Nuclear Information System (INIS)

Solmi, Rossella; Montroni, Isacco; Mattei, Gabriella; Taffurelli, Mario; Santini, Donatella; Pezzetti, Furio; Ruggeri, Alessandro; Castellani, Gastone; Guidotti, Lia; Coppola, Domenico; Strippoli, Pierluigi; Lauriola, Mattia; Francesconi, Mirko; Martini, Désirée; Voltattorni, Manuela; Ceccarelli, Claudio; Ugolini, Giampaolo; Rosati, Giancarlo; Zanotti, Simone

2008-01-01

EGFR is frequently overexpressed in colon cancer. We characterized HT-29 and Caco-2, human colon cancer cell lines, untreated and treated with cetuximab or gefitinib alone and in combination with EGF. Cell growth was determined using a variation on the MTT assay. Cell-cycle analysis was conducted by flow cytometry. Immunohistochemistry was performed to evaluate EGFR expression and scanning electron microscopy (SEM) evidenced the ultrastructural morphology. Gene expression profiling was performed using hybridization of the microarray Ocimum Pan Human 40 K array A. Caco-2 and HT-29 were respectively 66.25 and 59.24 % in G0/G1. They maintained this level of cell cycle distribution after treatment, suggesting a predominantly differentiated state. Treatment of Caco-2 with EGF or the two EGFR inhibitors produced a significant reduction in their viability. SEM clearly showed morphological cellular transformations in the direction of cellular death in both cell lines treated with EGFR inhibitors. HT-29 and Caco-2 displayed an important reduction of the microvilli (which also lose their erect position in Caco-2), possibly invalidating microvilli absorption function. HT-29 treated with cetuximab lost their boundary contacts and showed filipodi; when treated with gefitinib, they showed some vesicles: generally membrane reshaping is evident. Both cell lines showed a similar behavior in terms of on/off switched genes upon treatment with cetuximab. The gefitinib global gene expression pattern was different for the 2 cell lines; gefitinib treatment induced more changes, but directly correlated with EGF treatment. In cetuximab or gefitinib plus EGF treatments there was possible summation of the morphological effects: cells seemed more weakly affected by the transformation towards apoptosis. The genes appeared to be less stimulated than for single drug cases. This is the first study to have systematically investigated the effect of cetuximab or gefitinib, alone and in combination

Zebrafish Axenic Larvae Colonization with Human Intestinal Microbiota.

Science.gov (United States)

Arias-Jayo, Nerea; Alonso-Saez, Laura; Ramirez-Garcia, Andoni; Pardo, Miguel A

2018-04-01

The human intestine hosts a vast and complex microbial community that is vital for maintaining several functions related with host health. The processes that determine the gut microbiome composition are poorly understood, being the interaction between species, the external environment, and the relationship with the host the most feasible. Animal models offer the opportunity to understand the interactions between the host and the microbiota. There are different gnotobiotic mice or rat models colonized with the human microbiota, however, to our knowledge, there are no reports on the colonization of germ-free zebrafish with a complex human intestinal microbiota. In the present study, we have successfully colonized 5 days postfertilization germ-free zebrafish larvae with the human intestinal microbiota previously extracted from a donor and analyzed by high-throughput sequencing the composition of the transferred microbial communities that established inside the zebrafish gut. Thus, we describe for first time which human bacteria phylotypes are able to colonize the zebrafish digestive tract. Species with relevant interest because of their linkage to dysbiosis in different human diseases, such as Akkermansia muciniphila, Eubacterium rectale, Faecalibacterium prausnitzii, Prevotella spp., or Roseburia spp. have been successfully transferred inside the zebrafish digestive tract.

Protein expression profile of HT-29 human colon cancer cells after treatment with a cytotoxic daunorubicin-GnRH-III derivative bioconjugate.

Directory of Open Access Journals (Sweden)

Verena Natalie Schreier

Full Text Available Targeted delivery of chemotherapeutic agents is a new approach for the treatment of cancer, which provides increased selectivity and decreased systemic toxicity. We have recently developed a promising drug delivery system, in which the anticancer drug daunorubicin (Dau was attached via oxime bond to a gonadotropin-releasing hormone-III (GnRH-III derivative used as a targeting moiety (Glp-His-Trp-Lys(Ac-His-Asp-Trp-Lys(Da  = Aoa-Pro-Gly-NH2; Glp = pyroglutamic acid, Ac = acetyl; Aoa = aminooxyacetyl. This bioconjugate exerted in vitro cytostatic/cytotoxic effect on human breast, prostate and colon cancer cells, as well as significant in vivo tumor growth inhibitory effect on colon carcinoma bearing mice. In our previous studies, H-Lys(Dau = Aoa-OH was identified as the smallest metabolite produced in the presence of rat liver lysosomal homogenate, which was able to bind to DNA in vitro. To get a deeper insight into the mechanism of action of the bioconjugate, changes in the protein expression profile of HT-29 human colon cancer cells after treatment with the bioconjugate or free daunorubicin were investigated by mass spectrometry-based proteomics. Our results indicate that several metabolism-related proteins, molecular chaperons and proteins involved in signaling are differently expressed after targeted chemotherapeutic treatment, leading to the conclusion that the bioconjugate exerts its cytotoxic action by interfering with multiple intracellular processes.

The Effect of Fucoidan from the Brown Alga Fucus evanescence on the Activity of α-N-Acetylgalactosaminidase of Human Colon Carcinoma Cells

Directory of Open Access Journals (Sweden)

Irina Bakunina

2018-05-01

Full Text Available α-N-acetylgalactosaminidase (EC 3.2.1.49 (alpha-NaGalase catalyzes the hydrolysis of N-acetamido-2-deoxy-α-d-galactoside residues from non-reducing ends of various complex carbohydrates and glycoconjugates. It is known that human cancer cells express an alpha-NaGalase, which accumulates in the blood plasma of patients. The enzyme deglycosylates the Gc protein-derived macrophage activating factor (GcMAF and inhibits macrophage activity acting as an immunosuppressor. The high specific activity 0.033 ± 0.002 μmol mg−1 min−1 of the enzyme was found in human colon carcinoma cells DLD-1. The alpha-NaGalase of DLD-1 cells was isolated and biochemical characterized. The enzyme exhibits maximum activity at pH 5.2 and temperature 55 °C. The Km is 2.15 mM, Vmax–0.021 μmol min−1 mL−1, kcat–1.55 min−1 and kcat/Km–0.72 min−1 mM−1 at 37 °C, pH 5.2. The effects of fucoidan from the brown alga Fucus evanescence on the activity of alpha-NaGalase in human colon carcinoma DLD-1 cells and on the biosynthesis of this enzyme were investigated. It was shown that fucoidan did not inhibit free alpha-NaGalase, however, it reduced the expression of the enzyme in the DLD-1 cells at IC50 73 ± 4 μg mL−1.

Tryptophan autofluorescence imaging of neoplasms of the human colon

Science.gov (United States)

Banerjee, Bhaskar; Renkoski, Timothy; Graves, Logan R.; Rial, Nathaniel S.; Tsikitis, Vassiliki Liana; Nfonsom, Valentine; Pugh, Judith; Tiwari, Piyush; Gavini, Hemanth; Utzinger, Urs

2012-01-01

Detection of flat neoplasia is a major challenge in colorectal cancer screening, as missed lesions can lead to the development of an unexpected `incident' cancer prior to the subsequent endoscopy. The use of a tryptophan-related autofluorescence has been reported to be increased in murine intestinal dysplasia. The emission spectra of cells isolated from human adenocarcinoma and normal mucosa of the colon were studied and showed markedly greater emission intensity from cancerous cells compared to cells obtained from the surrounding normal mucosa. A proto-type multispectral imaging system optimized for ultraviolet macroscopic imaging of tissue was used to obtain autofluorescence images of surgical specimens of colonic neoplasms and normal mucosa after resection. Fluorescence images did not display the expected greater emission from the tumor as compared to the normal mucosa, most probably due to increased optical absorption and scattering in the tumors. Increased fluorescence intensity in neoplasms was observed however, once fluorescence images were corrected using reflectance images. Tryptophan fluorescence alone may be useful in differentiating normal and cancerous cells, while in tissues its autofluorescence image divided by green reflectance may be useful in displaying neoplasms.

Comparative effects of RRR-alpha- and RRR-gamma-tocopherol on proliferation and apoptosis in human colon cancer cell lines.

Science.gov (United States)

Campbell, Sharon E; Stone, William L; Lee, Steven; Whaley, Sarah; Yang, Hongsong; Qui, Min; Goforth, Paige; Sherman, Devin; McHaffie, Derek; Krishnan, Koyamangalath

2006-01-17

Mediterranean societies, with diets rich in vitamin E isoforms, have a lower risk for colon cancer than those of northern Europe and the Americas. Vitamin E rich diets may neutralize free radicals generated by fecal bacteria in the gut and prevent DNA damage, but signal transduction activities can occur independent of the antioxidant function. The term vitamin E represents eight structurally related compounds, each differing in their potency and mechanisms of chemoprevention. The RRR-gamma-tocopherol isoform is found primarily in the US diet, while RRR-alpha-tocopherol is highest in the plasma. The effectiveness of RRR-alpha- and RRR-gamma-tocopherol at inhibiting cell growth and inducing apoptosis in colon cancer cell lines with varying molecular characteristics (SW480, HCT-15, HCT-116 and HT-29) and primary colon cells (CCD-112CoN, nontransformed normal phenotype) was studied. Colon cells were treated with and without RRR-alpha- or RRR-gamma-tocopherol using varying tocopherol concentrations and time intervals. Cell proliferation and apoptosis were measured using the trypan blue assay, annexin V staining, DNA laddering and caspase activation. Treatment with RRR-gamma-tocopherol resulted in significant cell death for all cancer cell lines tested, while RRR-alpha-tocopherol did not. Further, RRR-gamma-tocopherol treatment showed no cytotoxicity to normal colon cells CCD-112CoN at the highest concentration and time point tested. RRR-gamma-tocopherol treatment resulted in cleavage of PARP, caspase 3, 7, and 8, but not caspase 9. Differences in the percentage cell death and apoptosis were observed in different cell lines suggesting that molecular differences in these cell lines may influence the ability of RRR-gamma-tocopherol to induce cell death. This is the first study to demonstrate that multiple colon cancer cell lines containing varying genetic alterations will under go growth reduction and apoptosis in the presence of RRR-gamma-tocopherol without damage to

Comparative effects of RRR-alpha- and RRR-gamma-tocopherol on proliferation and apoptosis in human colon cancer cell lines

International Nuclear Information System (INIS)

Campbell, Sharon E; Krishnan, Koyamangalath; Stone, William L; Lee, Steven; Whaley, Sarah; Yang, Hongsong; Qui, Min; Goforth, Paige; Sherman, Devin; McHaffie, Derek

2006-01-01

Mediterranean societies, with diets rich in vitamin E isoforms, have a lower risk for colon cancer than those of northern Europe and the Americas. Vitamin E rich diets may neutralize free radicals generated by fecal bacteria in the gut and prevent DNA damage, but signal transduction activities can occur independent of the antioxidant function. The term vitamin E represents eight structurally related compounds, each differing in their potency and mechanisms of chemoprevention. The RRR-γ-tocopherol isoform is found primarily in the US diet, while RRR-α-tocopherol is highest in the plasma. The effectiveness of RRR-α- and RRR-γ-tocopherol at inhibiting cell growth and inducing apoptosis in colon cancer cell lines with varying molecular characteristics (SW480, HCT-15, HCT-116 and HT-29) and primary colon cells (CCD-112CoN, nontransformed normal phenotype) was studied. Colon cells were treated with and without RRR-α- or RRR-γ-tocopherol using varying tocopherol concentrations and time intervals. Cell proliferation and apoptosis were measured using the trypan blue assay, annexin V staining, DNA laddering and caspase activation. Treatment with RRR-γ-tocopherol resulted in significant cell death for all cancer cell lines tested, while RRR-α-tocopherol did not. Further, RRR-γ-tocopherol treatment showed no cytotoxicity to normal colon cells CCD-112CoN at the highest concentration and time point tested. RRR-γ-tocopherol treatment resulted in cleavage of PARP, caspase 3, 7, and 8, but not caspase 9. Differences in the percentage cell death and apoptosis were observed in different cell lines suggesting that molecular differences in these cell lines may influence the ability of RRR-γ-tocopherol to induce cell death. This is the first study to demonstrate that multiple colon cancer cell lines containing varying genetic alterations will under go growth reduction and apoptosis in the presence of RRR-γ-tocopherol without damage to normal colon cells. The amount growth

Clone-specific expression, transcriptional regulation, and action of interleukin-6 in human colon carcinoma cells

International Nuclear Information System (INIS)

Brozek, Wolfgang; Bises, Giovanna; Fabjani, Gerhild; Cross, Heide S; Peterlik, Meinrad

2008-01-01

Many cancer cells produce interleukin-6 (IL-6), a cytokine that plays a role in growth stimulation, metastasis, and angiogenesis of secondary tumours in a variety of malignancies, including colorectal cancer. Effectiveness of IL-6 in this respect may depend on the quantity of basal and inducible IL-6 expressed as the tumour progresses through stages of malignancy. We therefore have evaluated the effect of IL-6 modulators, i.e. IL-1β, prostaglandin E 2 , 17β-estradiol, and 1,25-dihydroxyvitamin D 3 , on expression and synthesis of the cytokine at different stages of tumour progression. We utilized cultures of the human colon carcinoma cell clones Caco-2/AQ, COGA-1A and COGA-13, all of which expressed differentiation and proliferation markers typical of distinct stages of tumour progression. IL-6 mRNA and protein levels were assayed by RT-PCR and ELISA, respectively. DNA sequencing was utilized to detect polymorphisms in the IL-6 gene promoter. IL-6 mRNA and protein concentrations were low in well and moderately differentiated Caco-2/AQ and COGA-1A cells, but were high in poorly differentiated COGA-13 cells. Addition of IL-1β (5 ng/ml) to a COGA-13 culture raised IL-6 production approximately thousandfold via a prostaglandin-independent mechanism. Addition of 17β-estradiol (10 -7 M) reduced basal IL-6 production by one-third, but IL-1β-inducible IL-6 was unaffected. Search for polymorphisms in the IL-6 promoter revealed the presence of a single haplotype, i.e., -597A/-572G/-174C, in COGA-13 cells, which is associated with a high degree of transcriptional activity of the IL-6 gene. IL-6 blocked differentiation only in Caco-2/AQ cells and stimulated mitosis through up-regulation of c-myc proto-oncogene expression. These effects were inhibited by 10 -8 M 1,25-dihydroxyvitamin D 3 . In human colon carcinoma cells derived from well and moderately differentiated tumours, IL-6 expression is low and only marginally affected, if at all, by PGE 2 , 1,25-dihydroxyvitamin D

Laminarin Induces Apoptosis of Human Colon Cancer LOVO Cells through a Mitochondrial Pathway

Directory of Open Access Journals (Sweden)

He Zhang

2012-08-01

Full Text Available Many scientific studies have shown that laminarin has anti-tumor effects, but the anti-tumor mechanism was unclear. The purpose of this study was to investigate the effect of laminarin on the induction of apoptosis in human colon cancer LOVO cells and the molecular mechanism involved. LOVO cells were treated with different concentrations of laminarin at different times. Morphology observations were performed to determine the effects of laminarin on apoptosis of LOVO cells. Flow cytometry (FCM was used to detect the level of intracellular reactive oxygen species (ROS and pH. Laser scanning confocal microscope (LSCM was used to analyze intracellular calcium ion concentration, mitochondrion permeability transition pore (MPTP and mitochondrial membrane potential (MMP. Western blotd were performed to analyze the expressions of Cyt-C, Caspase-9 and -3. The results showed the apoptosis morphology, which showed cell protuberance, concentrated cytoplasm and apoptotic bodies, was obvious after 72 h treatment. Laminarin treatment for 24 h increased the intracellular level of ROS and Ca²⁺; decreased pH value; activated intracellular MPTP and decreased MMP in dose-dependent manners. It also induced the release of Cyt-C and the activation of Caspase-9 and -3. In conclusion, laminarin induces LOVO cell apoptosis through a mitochondrial pathway, suggesting that it could be a potent agent for cancer prevention and treatment.

Chemopreventive properties of raisins originating from Greece in colon cancer cells.

Science.gov (United States)

Kountouri, Aggeliki M; Gioxari, Aristea; Karvela, Evangelia; Kaliora, Andriana C; Karvelas, Michalis; Karathanos, Vaios T

2013-02-26

Colorectal cancer is one of the major causes of cancer-related mortality in humans in both developed and developing countries. Dietary patterns influence the risk of colon cancer development, while plant-derived foods have gained great interest, due to the high content of antioxidants. Corinthian raisins (Currants, CR) and Sultanas (S) (Vitis vinifera L., Vitaceae) are dried vine fruits produced in Greece with many culinary uses in both the Mediterranean and the Western nutrition. In the present study, we investigated the effects of CR and S on human colon cancer cells. Methanol extracts of CR and S were used at different concentrations. The total polyphenol content and anti-radical activity were measured by Folin-Ciocalteu and DPPH, respectively. Antioxidant, anti-inflammatory and anti-proliferative effects on HT29 cell culture were evaluated. All extracts exhibited DPPH˙ scavenging activity in a dose-dependent manner. Both products suppressed cell proliferation, while the levels of glutathione and cyclooxygenase 2 were significantly decreased. A significant reduction in IL-8 levels and NF-kappaB p65 activation was also observed. Both antioxidant and anti-inflammatory effects were dependent on the duration of exposure. Results indicate that the methanol extracts of CR and S exhibit anti-radical activity in vitro, as well as cancer preventive efficacy on colon cancer cells, with S having slightly higher activity. The beneficial properties of these unique dried grapes are attributed to their high content of phenolic compounds.

Cytotoxicity effect of Zataria multiflora Boiss. on two human colon carcinoma cell lines

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F. Sharififar

2017-10-01

Full Text Available Background and objectives: Natural products are one of the major sources for investigations of novel medicines. Zataria multiflora Boiss (ZM has shown pharmacological activities especially in gastrointestinal tract; however, there are limited studies about its cytotoxicity effects. In this study, the effect of Zataria multiflora was examined on two colon cancer cell lines (SW-48 and HT-29. Methods: Hydro-alcoholic extract of ZM and its fractions including chloroform, petroleum ether and methanol extract were prepared by warm maceration method. Different concentrations were prepared and examined on SW-48 and HT-29 cell lines using 2-(4, 5-dimethylthiazol-2-yl 2, 5-diphenyltetrazolium bromide (MTT assay. Results: The results of the present study have shown the cytotoxic effect of some fractions of ZM. The most considerable cytotoxic effect was shown against HT-29 cell line. Also, total ZM extract and the petroleum ether fraction demonstrated cytotoxic effects with IC50 values of 44.22 and 33.42 µg/ml on SW-48 and HT-29 cell lines, respectively. Conclusion: Zataria multiflora was cytotoxic to against colon cancer cell lines HT-29 and SW-48.

Cathelicidin suppresses colon cancer development by inhibition of cancer associated fibroblasts

Directory of Open Access Journals (Sweden)

Cheng M

2014-12-01

Full Text Available Michelle Cheng,1,* Samantha Ho,1,* Jun Hwan Yoo,1,2,* Deanna Hoang-Yen Tran,1,* Kyriaki Bakirtzi,1 Bowei Su,1 Diana Hoang-Ngoc Tran,1 Yuzu Kubota,1 Ryan Ichikawa,1 Hon Wai Koon1 1Center for Inflammatory Bowel Diseases, Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA; 2Digestive Disease Center, CHA University Bundang Medical Center, Seongnam, Republic of Korea *These authors share co-first authorship Background: Cathelicidin (LL-37 in humans and mCRAMP in mice represents a family of endogenous antimicrobial and anti-inflammatory peptides. Cancer-associated fibroblasts can promote the proliferation of colon cancer cells and growth of colon cancer tumors. Methods: We examined the role of cathelicidin in the development of colon cancer, using subcutaneous human HT-29 colon-cancer-cell-derived tumor model in nude mice and azoxymethane- and dextran sulfate-mediated colon cancer model in C57BL/6 mice. We also determined the indirect antitumoral mechanism of cathelicidin via the inhibition of epithelial–mesenchymal transition (EMT of colon cancer cells and fibroblast-supported colon cancer cell proliferation. Results: Intravenous administration of cathelicidin expressing adeno-associated virus significantly reduced the size of tumors, tumor-derived collagen expression, and tumor-derived fibroblast expression in HT-29-derived subcutaneous tumors in nude mice. Enema administration of the mouse cathelicidin peptide significantly reduced the size and number of colonic tumors in azoxymethane- and dextran sulfate-treated mice without inducing apoptosis in tumors and the adjacent normal colonic tissues. Cathelicidin inhibited the collagen expression and vimentin-positive fibroblast expression in colonic tumors. Cathelicidin did not directly affect HT-29 cell viability, but did significantly reduce tumor growth factor-ß1-induced EMT of colon cancer cells. Media conditioned by the

Polystyrene nanoparticles facilitate the internalization of impermeable biomolecules in non-tumour and tumour cells from colon epithelium

Energy Technology Data Exchange (ETDEWEB)

Cabeza, Laura [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain); Cano-Cortés, Victoria; Rodríguez, María J. [University of Granada, Department of Pharmaceutical and Organic Chemistry (Spain); Vélez, Celia; Melguizo, Consolación, E-mail: melguizo@ugr.es [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain); Sánchez-Martín, Rosario M., E-mail: rmsanchez@ugr.es [University of Granada, Department of Pharmaceutical and Organic Chemistry (Spain); Prados, Jose [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain)

2015-01-15

Advanced colon cancer has a poor prognosis due to the limited effectiveness of current chemotherapies. Treatment failures may be avoided by the utilization of nanoparticles, which can enhance the effects of antitumor drugs, reduce their side effects and increase their directionality. Polystyrene nanoparticles have shown high biocompatibility and appropriate physicochemical properties and may represent a novel and more effective approach against colon cancer. In the present study, polystyrene nanoparticles were synthesized and fluorescently labelled, analyzing their cell internalization, intracellular localization and capacity to release transported molecules in tumour and non-tumour human colon cell lines (T84 and CCD-18). Flow cytometry and fluorescence microscopy studies demonstrated that polystyrene nanoparticles are an effective vehicle for the intracellular delivery of small molecules into colon epithelium cells. The percentage cell uptake was around 100 % in both T84 and CCD-18 cell lines after only 24 h of exposure and was cell confluence-independent. The polystyrene nanoparticles showed no cytotoxicity in either colon cell line. It was found that small molecules can be efficiently delivered into colon cells by using a disulphide bridge as release strategy. Analysis of the influence of the functionalization of the polystyrene nanoparticles surface on the internalization efficiency revealed some morphological changes in these cells. These results demonstrate that polystyrene nanoparticles may improve the transport of biomolecules into colon cells which could have a potential application in chemotherapeutic treatment against colon cancer.

Polystyrene nanoparticles facilitate the internalization of impermeable biomolecules in non-tumour and tumour cells from colon epithelium

International Nuclear Information System (INIS)

Cabeza, Laura; Cano-Cortés, Victoria; Rodríguez, María J.; Vélez, Celia; Melguizo, Consolación; Sánchez-Martín, Rosario M.; Prados, Jose

2015-01-01

Advanced colon cancer has a poor prognosis due to the limited effectiveness of current chemotherapies. Treatment failures may be avoided by the utilization of nanoparticles, which can enhance the effects of antitumor drugs, reduce their side effects and increase their directionality. Polystyrene nanoparticles have shown high biocompatibility and appropriate physicochemical properties and may represent a novel and more effective approach against colon cancer. In the present study, polystyrene nanoparticles were synthesized and fluorescently labelled, analyzing their cell internalization, intracellular localization and capacity to release transported molecules in tumour and non-tumour human colon cell lines (T84 and CCD-18). Flow cytometry and fluorescence microscopy studies demonstrated that polystyrene nanoparticles are an effective vehicle for the intracellular delivery of small molecules into colon epithelium cells. The percentage cell uptake was around 100 % in both T84 and CCD-18 cell lines after only 24 h of exposure and was cell confluence-independent. The polystyrene nanoparticles showed no cytotoxicity in either colon cell line. It was found that small molecules can be efficiently delivered into colon cells by using a disulphide bridge as release strategy. Analysis of the influence of the functionalization of the polystyrene nanoparticles surface on the internalization efficiency revealed some morphological changes in these cells. These results demonstrate that polystyrene nanoparticles may improve the transport of biomolecules into colon cells which could have a potential application in chemotherapeutic treatment against colon cancer

Prehistoric human colonization of India

Indian Academy of Sciences (India)

Unknown

J. Biosci. | Vol. 26 | No. 4 | Suppl. | November 2001. V N Misra. 492 ... humans differ from the other apes in their upright posture, ... characterized by Levallois flakes and blades and by the ... and the coastal region running parallel to them, northeast ..... November 2001. Prehistoric human colonization of India. 497. Figure 1.

Identification of colonic fibroblast secretomes reveals secretory factors regulating colon cancer cell proliferation.

Science.gov (United States)

Chen, Sun-Xia; Xu, Xiao-En; Wang, Xiao-Qing; Cui, Shu-Jian; Xu, Lei-Lei; Jiang, Ying-Hua; Zhang, Yang; Yan, Hai-Bo; Zhang, Qian; Qiao, Jie; Yang, Peng-Yuan; Liu, Feng

2014-10-14

Stromal microenvironment influences tumor cell proliferation and migration. Fibroblasts represent the most abundant stromal constituents. Here, we established two pairs of normal fibroblast (NF) and cancer-associated fibroblast (CAF) cultures from colorectal adenocarcinoma tissues and the normal counterparts. The NFs and CAFs were stained positive for typical fibroblast markers and inhibited colon cancer (CC) cell proliferation in in vitro cocultures and in xenograft mouse models. The fibroblast conditioned media were analyzed using LC-MS and 227 proteins were identified at a false discovery rate of 1.3%, including 131 putative secretory and 20 plasma membrane proteins. These proteins were enriched for functional categories of extracellular matrix, adhesion, cell motion, inflammatory response, redox homeostasis and peptidase inhibitor. Secreted protein acidic and rich in cysteine, transgelin, follistatin-related protein 1 (FSTL1) and decorin was abundant in the fibroblast secretome as confirmed by Western blot. Silencing of FSTL1 and transgelin in colonic fibroblast cell line CCD-18Co induced an accelerated proliferation of CC cells in cocultures. Exogenous FSTL1 attenuates CC cell proliferation in a negative fashion. FSTL1 was upregulated in CC patient plasma and cancerous tissues but had no implication in prognosis. Our results provided novel insights into the molecular signatures and modulatory role of CC associated fibroblasts. In this study, a label-free LC-MS was performed to analyze the secretomes of two paired primary fibroblasts, which were isolated from fresh surgical specimen of colorectal adenocarcinoma and adjacent normal colonic tissues and exhibited negative modulatory activity for colon cancer cell growth in in vitro cocultures and in vivo xenograph mouse models. Follistatin-related protein 1 was further revealed to be one of the stroma-derived factors of potential suppression role for colon cancer cell proliferation. Our results provide novel

Growth-inhibitory effects of a mineralized extract from the red marine algae, Lithothamnion calcareum, on Ca(2+)-sensitive and Ca(2+)-resistant human colon carcinoma cells.

Science.gov (United States)

Aslam, Muhammad Nadeem; Bhagavathula, Narasimharao; Paruchuri, Tejaswi; Hu, Xin; Chakrabarty, Subhas; Varani, James

2009-10-08

Proliferation and differentiation were assessed in a series of human colon carcinoma cell lines in response to a mineral-rich extract derived from the red marine algae, Lithothamnion calcareum. The extract contains 12% Ca2+, 1% Mg2+, and detectable amounts of 72 trace elements, but essentially no organic material. The red algae extract was as effective as inorganic Ca2+ alone in suppressing growth and inducing differentiation of colon carcinoma cells that are responsive to a physiological level of extracellular Ca2+ (1.4mM). However, with cells that are resistant to Ca2+ alone, the extract was still able to reduce proliferation and stimulate differentiation.

Growth-inhibitory effects of a mineralized extract from the red marine algae, Lithothamnion calcareum, on Ca2+-sensitive and Ca2+-resistant human colon carcinoma cells

Science.gov (United States)

Nadeem Aslam, Muhammad; Bhagavathula, Narasimharao; Paruchuri, Tejaswi; Hu, Xin; Chakrabarty, Subhas; Varani, James

2009-01-01

Proliferation and differentiation were assessed in a series of human colon carcinoma cell lines in response to a mineral-rich extract derived from the red marine algae, Lithothamnion calcareum. The extract contains 12% Ca2+, 1% Mg2+, and detectable amounts of 72 trace elements, but essentially no organic material. The red algae extract was as effective as inorganic Ca2+ alone in suppressing growth and inducing differentiation of colon carcinoma cells that are responsive to a physiological level of extracellular Ca2+ (1.4 mM). However, with cells that are resistant to Ca2+ alone, the extract was still able to reduce proliferation and stimulate differentiation. PMID:19394137

FXR silencing in human colon cancer by DNA methylation and KRAS signaling.

Science.gov (United States)

Bailey, Ann M; Zhan, Le; Maru, Dipen; Shureiqi, Imad; Pickering, Curtis R; Kiriakova, Galina; Izzo, Julie; He, Nan; Wei, Caimiao; Baladandayuthapani, Veerabhadran; Liang, Han; Kopetz, Scott; Powis, Garth; Guo, Grace L

2014-01-01

Farnesoid X receptor (FXR) is a bile acid nuclear receptor described through mouse knockout studies as a tumor suppressor for the development of colon adenocarcinomas. This study investigates the regulation of FXR in the development of human colon cancer. We used immunohistochemistry of FXR in normal tissue (n = 238), polyps (n = 32), and adenocarcinomas, staged I-IV (n = 43, 39, 68, and 9), of the colon; RT-quantitative PCR, reverse-phase protein array, and Western blot analysis in 15 colon cancer cell lines; NR1H4 promoter methylation and mRNA expression in colon cancer samples from The Cancer Genome Atlas; DNA methyltransferase inhibition; methyl-DNA immunoprecipitation (MeDIP); bisulfite sequencing; and V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) knockdown assessment to investigate FXR regulation in colon cancer development. Immunohistochemistry and quantitative RT-PCR revealed that expression and function of FXR was reduced in precancerous lesions and silenced in a majority of stage I-IV tumors. FXR expression negatively correlated with phosphatidylinositol-4, 5-bisphosphate 3 kinase signaling and the epithelial-to-mesenchymal transition. The NR1H4 promoter is methylated in ~12% colon cancer The Cancer Genome Atlas samples, and methylation patterns segregate with tumor subtypes. Inhibition of DNA methylation and KRAS silencing both increased FXR expression. FXR expression is decreased early in human colon cancer progression, and both DNA methylation and KRAS signaling may be contributing factors to FXR silencing. FXR potentially suppresses epithelial-to-mesenchymal transition and other oncogenic signaling cascades, and restoration of FXR activity, by blocking silencing mechanisms or increasing residual FXR activity, represents promising therapeutic options for the treatment of colon cancer.

Tussilagone suppresses colon cancer cell proliferation by promoting the degradation of β-catenin

International Nuclear Information System (INIS)

Li, Hua; Lee, Hwa Jin; Ahn, Yeon Hwa; Kwon, Hye Jin; Jang, Chang-Young; Kim, Woo-Young; Ryu, Jae-Ha

2014-01-01

Highlights: •Tussilagone (TSL) was purified from plant as an inhibitor of Wnt/β-catenin pathway. •TSL suppressed the β-catenin/T-cell factor transcriptional activity. •The proteasomal degradation of β-catenin was induced by TSL. •TSL suppressed the Wnt/β-catenin target genes, cyclin D1 and c-myc. •TSL inhibit the proliferation of colon cancer cells. -- Abstract: Abnormal activation of the Wnt/β-catenin signaling pathway frequently induces colon cancer progression. In the present study, we identified tussilagone (TSL), a compound isolated from the flower buds of Tussilago farfara, as an inhibitor on β-catenin dependent Wnt pathway. TSL suppressed β-catenin/T-cell factor transcriptional activity and down-regulated β-catenin level both in cytoplasm and nuclei of HEK293 reporter cells when they were stimulated by Wnt3a or activated by an inhibitor of glycogen synthase kinase-3β. Since the mRNA level was not changed by TSL, proteasomal degradation might be responsible for the decreased level of β-catenin. In SW480 and HCT116 colon cancer cell lines, TSL suppressed the β-catenin activity and also decreased the expression of cyclin D1 and c-myc, representative target genes of the Wnt/β-catenin signaling pathway, and consequently inhibited the proliferation of colon cancer cells. Taken together, TSL might be a potential chemotherapeutic agent for the prevention and treatment of human colon cancer

Tussilagone suppresses colon cancer cell proliferation by promoting the degradation of β-catenin

Energy Technology Data Exchange (ETDEWEB)

Li, Hua [College of Pharmacy and Research Center for Cell Fate Control, Sookmyung Women’s University, 52 Hyochangwon-Gil, Yongsan-Gu, Seoul 140-742 (Korea, Republic of); Lee, Hwa Jin [Department of Natural Medicine Resources, Semyung University, 65 Semyung-ro, Jecheon, Chungbuk 390-711 (Korea, Republic of); Ahn, Yeon Hwa; Kwon, Hye Jin; Jang, Chang-Young; Kim, Woo-Young [College of Pharmacy and Research Center for Cell Fate Control, Sookmyung Women’s University, 52 Hyochangwon-Gil, Yongsan-Gu, Seoul 140-742 (Korea, Republic of); Ryu, Jae-Ha, E-mail: ryuha@sookmyung.ac.kr [College of Pharmacy and Research Center for Cell Fate Control, Sookmyung Women’s University, 52 Hyochangwon-Gil, Yongsan-Gu, Seoul 140-742 (Korea, Republic of)

2014-01-03

Highlights: •Tussilagone (TSL) was purified from plant as an inhibitor of Wnt/β-catenin pathway. •TSL suppressed the β-catenin/T-cell factor transcriptional activity. •The proteasomal degradation of β-catenin was induced by TSL. •TSL suppressed the Wnt/β-catenin target genes, cyclin D1 and c-myc. •TSL inhibit the proliferation of colon cancer cells. -- Abstract: Abnormal activation of the Wnt/β-catenin signaling pathway frequently induces colon cancer progression. In the present study, we identified tussilagone (TSL), a compound isolated from the flower buds of Tussilago farfara, as an inhibitor on β-catenin dependent Wnt pathway. TSL suppressed β-catenin/T-cell factor transcriptional activity and down-regulated β-catenin level both in cytoplasm and nuclei of HEK293 reporter cells when they were stimulated by Wnt3a or activated by an inhibitor of glycogen synthase kinase-3β. Since the mRNA level was not changed by TSL, proteasomal degradation might be responsible for the decreased level of β-catenin. In SW480 and HCT116 colon cancer cell lines, TSL suppressed the β-catenin activity and also decreased the expression of cyclin D1 and c-myc, representative target genes of the Wnt/β-catenin signaling pathway, and consequently inhibited the proliferation of colon cancer cells. Taken together, TSL might be a potential chemotherapeutic agent for the prevention and treatment of human colon cancer.

Inhibition effect of Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis and their related products on human colonic smooth muscle in vitro.

Directory of Open Access Journals (Sweden)

Jing Gong

Full Text Available To investigate the effects of four strains, generally used in clinic, including Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis, and their related products on human colonic smooth muscle in vitro.Human colonic circular muscle strips obtained from disease-free margins of resected segments from 25 patients with colorectal cancer were isometrically examined in a constant-temperature organ bath and exposed to different concentrations of living bacteria, sonicated cell fractions and cell-free supernatant (CFS. The area under the curve (AUC representing the contractility of smooth muscle strips was calculated.(1 The four living probiotics inhibited the contractility of human colonic muscle strips only at high concentration (1010 CFUs/mL, all P0.05.Four common probiotics related products, including the sonicated cell fractions and the CFS, obviously inhibited human colonic smooth muscles strips contraction in a dose-dependent manner. Only high concentration living probiotics (1010 CFUs/mL can inhibit the colonic smooth muscles strips contraction. The NO pathway may be partly involved in the inhibitory effect of CFS from Streptococcus thermophilus and Enterococcus faecalis.

Inhibition of Epidermal Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor Phosphorylation on Tumor-Associated Endothelial Cells Leads to Treatment of Orthotopic Human Colon Cancer in Nude Mice

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Takamitsu Sasaki

2007-12-01

Full Text Available The purpose of our study was to determine whether the dual inhibition of epidermal growth factor receptor (EGFR and vascular endothelial growth factor receptor (VEGFR signaling pathways in tumor-associated endothelial cells can inhibit the progressive growth of human colon carcinoma in the cecum of nude mice. SW620CE2 human colon cancer cells growing in culture and orthotopically in the cecum of nude mice expressed a high level of transforming growth factor alpha (TGF-α and vascular endothelial growth factor (VEGF but were negative for EGFR, human epidermal growth factor receptor 2 (HER2, VEGFR. Double immunofluorescence staining revealed that tumorassociated endothelial cells expressed EGFR, VEGFR2, phosphorylated EGFR (pEGFR, phosphorylated VEGFR (pVEGFR. Treatment of mice with either 7H-pyrrolo [2,3-d]-pyrimidine lead scaffold (AEE788; an inhibitor of EGFR and VEGFR tyrosine kinase or CPT-11 as single agents significantly inhibited the growth of cecal tumors (P < .01; this decrease was even more pronounced with AEE788 combined with CPT-11 (P < .001. AEE788 alone or combined with CPT-11 also inhibited the expression of pEGFR and pVEGFR on tumor-associated endothelial cells, significantly decreased vascularization and tumor cell proliferation, increased the level of apoptosis in both tumorassociated endothelial cells and tumor cells. These data demonstrate that targeting EGFR and VEGFR signaling on tumor-associated endothelial cells provides a viable approach for the treatment of colon cancer.

Effects of homeodomain protein CDX2 expression on the proliferation and migration of lovo colon cancer cells.

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Zheng, Jian-bao; Sun, Xue-jun; Qi, Jie; Li, Shou-shuai; Wang, Wei; Ren, Hai-liang; Tian, Yong; Lu, Shao-ying; Du, Jun-kai

2011-09-01

The homeobox gene, CDX2, plays a major role in development, especially in the gut, and also functions as a tumor suppressor in the adult colon. In the present study, we investigated the effects of CDX2 expression on the proliferation, migration, and apoptosis of the human colon cancer cell line, Lovo. Lovo cells exogenously expressing CDX2 exhibited no significant differences in the percentage of cells in G1- and S-phase or in apoptosis, as determined by flow cytometry. MTT assay also confirmed that CDX2 expression had no effect on proliferation in these cells. Interestingly, conditioned medium collected from CDX2-overexpressing Lovo cells showed a significant decrease in secretion of MMP-2 and the invasive potential of these cells was significantly inhibited. Collectively, these data suggest that CDX2 may play a critical role in the migration and metastasis of colon carcinoma and over-expression of CDX2 in colon cancer cells markedly inhibits invasion. Based on these results, exogenous expression of CDX2 might be a promising option in the treatment of colon carcinoma.

Establishment and Analysis of Cancer Stem-Like and Non-Cancer Stem-Like Clone Cells from the Human Colon Cancer Cell Line SW480.

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Akari Takaya

Full Text Available Human cancer stem-like cells (CSCs/cancer-initiating cells (CICs can be isolated as side population (SP cells, aldehyde dehydrogenase high (ALDHhigh cells or cell surface marker-positive cells including CD44+ cells and CD133+ cells. CSCs/CICs and non-CSCs/CICs are unstable in in vitro culture, and CSCs/CICs can differentiate into non-CSCs/CICs and some non-CSCs/CICs can dedifferentiate into CSCs/CICs. Therefore, experiments using a large amount of CSCs/CICs are technically very difficult. In this study, we isolated single cell clones from SP cells and main population (MP cells derived from the human colon cancer cell line SW480. SP analysis revealed that SP clone cells had relatively high percentages of SP cells, whereas MP clone cells showed very few SP cells, and the phenotypes were sustainable for more than 2 months of in vitro culture. Xenograft transplantation revealed that SP clone cells have higher tumor-initiating ability than that of MP clone cells and SP clone cell showed higher chemo-resistance compared with MP clone cells. These results indicate that SP clone cells derived from SW480 cells are enriched with CSCs/CICs, whereas MP clone cells are pure non-CSCs/CICs. SP clone cells and MP clone cells are a very stable in vitro CSC/CIC-enriched and non-CSC/CIC model for further analysis.

Establishment and Analysis of Cancer Stem-Like and Non-Cancer Stem-Like Clone Cells from the Human Colon Cancer Cell Line SW480.

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Takaya, Akari; Hirohashi, Yoshihiko; Murai, Aiko; Morita, Rena; Saijo, Hiroshi; Yamamoto, Eri; Kubo, Terufumi; Nakatsugawa, Munehide; Kanaseki, Takayuki; Tsukahara, Tomohide; Tamura, Yasuaki; Takemasa, Ichiro; Kondo, Toru; Sato, Noriyuki; Torigoe, Toshihiko

2016-01-01

Human cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) can be isolated as side population (SP) cells, aldehyde dehydrogenase high (ALDHhigh) cells or cell surface marker-positive cells including CD44+ cells and CD133+ cells. CSCs/CICs and non-CSCs/CICs are unstable in in vitro culture, and CSCs/CICs can differentiate into non-CSCs/CICs and some non-CSCs/CICs can dedifferentiate into CSCs/CICs. Therefore, experiments using a large amount of CSCs/CICs are technically very difficult. In this study, we isolated single cell clones from SP cells and main population (MP) cells derived from the human colon cancer cell line SW480. SP analysis revealed that SP clone cells had relatively high percentages of SP cells, whereas MP clone cells showed very few SP cells, and the phenotypes were sustainable for more than 2 months of in vitro culture. Xenograft transplantation revealed that SP clone cells have higher tumor-initiating ability than that of MP clone cells and SP clone cell showed higher chemo-resistance compared with MP clone cells. These results indicate that SP clone cells derived from SW480 cells are enriched with CSCs/CICs, whereas MP clone cells are pure non-CSCs/CICs. SP clone cells and MP clone cells are a very stable in vitro CSC/CIC-enriched and non-CSC/CIC model for further analysis.

Cytotoxic, Anti-Proliferative and Apoptosis Activity of l-Amino Acid Oxidase from Malaysian Cryptelytrops purpureomaculatus (CP-LAAO) Venom on Human Colon Cancer Cells.

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Zainal Abidin, Syafiq Asnawi; Rajadurai, Pathmanathan; Hoque Chowdhury, Md Ezharul; Othman, Iekhsan; Naidu, Rakesh

2018-06-08

The aim of this study is to investigate the potential anti-cancer activity of l-amino acid oxidase (CP-LAAO) purified from the venom of Cryptelytrops purpureomaculatus on SW480 and SW620 human colon cancer cells. Mass spectrometry guided purification was able to identify and purify CP-LAAO. Amino acid variations identified from the partial protein sequence of CP-LAAO may suggest novel variants of these proteins. The activity of the purified CP-LAAO was confirmed with o-phenyldiamine (OPD)-based spectrophotometric assay. CP-LAAO demonstrated time- and dose-dependent cytotoxic activity and the EC 50 value was determined at 13 µg/mL for both SW480 and SW620 cells. Significant increase of caspase-3 activity, reduction of Bcl-2 levels, as well as morphological changes consistent with apoptosis were demonstrated by CP-LAAO. Overall, these data provide evidence on the potential anti-cancer activity of CP-LAAO from the venom of Malaysian C. purpureomaculatus for therapeutic intervention of human colon cancer.

Diet-Induced Obesity Is Associated with an Impaired NK Cell Function and an Increased Colon Cancer Incidence

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Ina Bähr

2017-01-01

Full Text Available Obesity is associated with an increased colon cancer incidence, but underlying mechanisms remained unclear. Previous studies showed altered Natural killer (NK cell functions in obese individuals. Therefore, we studied the impact of an impaired NK cell functionality on the increased colon cancer risk in obesity. In vitro investigations demonstrated a decreased IFN-γ secretion and cytotoxicity of human NK cells against colon tumor cells after NK cell preincubation with the adipokine leptin. In addition, leptin incubation decreased the expression of activating NK cell receptors. In animal studies, colon cancer growth was induced by injection of azoxymethane (AOM in normal weight and diet-induced obese rats. Body weight and visceral fat mass were increased in obese animals compared to normal weight rats. AOM-treated obese rats showed an increased quantity, size, and weight of colon tumors compared to the normal weight tumor group. Immunohistochemical analyses demonstrated a decreased number of NK cells in spleen and liver in obesity. Additionally, the expression levels of activating NK cell receptors were lower in spleen and liver of obese rats. The results show for the first time that the decreased number and impaired NK cell function may be one cause for the higher colon cancer risk in obesity.

Induction of apoptosis by tomato using space mutation breeding in human colon cancer SW480 and HT-29 cells.

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Shi, Jiahui; Yang, Bin; Feng, Pan; Li, Duo; Zhu, Jiajin

2010-03-15

As far as we know, there have been no reports concerning the functional characteristics of tomatoes using space mutation breeding. The aim of this study was to evaluate the anti-colon cancer effect of tomatoes M1 and M2 using space mutation breeding. In the present study, obvious anti-cancer activity was shown with tomato juice of M1 and M2 and their parent CK treatment in colon cancer cell lines SW480 and HT-29 in cell growth inhibition. In addition, SW480 cells were more sensitive to M1 and M2 than HT-29 cells in cell apoptosis. Furthermore, M1 and M2 induced cell cycle arrest both in G0-G1 and G2/M phases. These data suggest that consumption of tomato using space mutation breeding may provide benefits to inhibit growth of colon cancer cells. Therefore, tomato production using space mutation breeding may be a good candidate for development as a dietary supplement in drug therapy for colon cancer.

In Vitro Evaluation of the Impact of the Probiotic E. coli Nissle 1917 on Campylobacter jejuni's Invasion and Intracellular Survival in Human Colonic Cells.

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Helmy, Yosra A; Kassem, Issmat I; Kumar, Anand; Rajashekara, Gireesh

2017-01-01

Campylobacter jejuni is a leading cause of bacterial food poisoning in humans. Due to the rise in antibiotic-resistant Campylobacter , there exists a need to develop antibiotic-independent interventions to control infections in humans. Here, we evaluated the impact of Escherichia coli Nissle 1917 (EcN), a probiotic strain, on C. jejuni's invasion and intracellular survival in polarized human colonic cells (HT-29). To further understand how EcN mediates its impact, the expression of 84 genes associated with tight junctions and cell adhesion was profiled in HT-29 cells after treatment with EcN and challenge with C. jejuni . The pre-treatment of polarized HT-29 cells with EcN for 4 h showed a significant effect on C. jejuni 's invasion (∼2 log reduction) of the colonic cells. Furthermore, no intracellular C. jejuni were recovered from EcN pre-treated HT-29 cells at 24 h post-infection. Other probiotic strains tested had no significant impact on C. jejuni invasion and intracellular survival. C. jejuni decreased the expression of genes associated with epithelial cells permeability and barrier function in untreated HT-29 cells. However, EcN positively affected the expression of genes that are involved in enhanced intestinal barrier function, decreased cell permeability, and increased tight junction integrity. The results suggest that EcN impedes C. jejuni invasion and subsequent intracellular survival by affecting HT-29 cells barrier function and tight junction integrity. We conclude that EcN might be a viable alternative for controlling C. jejuni infections.

Comparative effects of RRR-alpha- and RRR-gamma-tocopherol on proliferation and apoptosis in human colon cancer cell lines

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Sherman Devin

2006-01-01

Full Text Available Abstract Background Mediterranean societies, with diets rich in vitamin E isoforms, have a lower risk for colon cancer than those of northern Europe and the Americas. Vitamin E rich diets may neutralize free radicals generated by fecal bacteria in the gut and prevent DNA damage, but signal transduction activities can occur independent of the antioxidant function. The term vitamin E represents eight structurally related compounds, each differing in their potency and mechanisms of chemoprevention. The RRR-γ-tocopherol isoform is found primarily in the US diet, while RRR-α-tocopherol is highest in the plasma. Methods The effectiveness of RRR-α- and RRR-γ-tocopherol at inhibiting cell growth and inducing apoptosis in colon cancer cell lines with varying molecular characteristics (SW480, HCT-15, HCT-116 and HT-29 and primary colon cells (CCD-112CoN, nontransformed normal phenotype was studied. Colon cells were treated with and without RRR-α- or RRR-γ-tocopherol using varying tocopherol concentrations and time intervals. Cell proliferation and apoptosis were measured using the trypan blue assay, annexin V staining, DNA laddering and caspase activation. Results Treatment with RRR-γ-tocopherol resulted in significant cell death for all cancer cell lines tested, while RRR-α-tocopherol did not. Further, RRR-γ-tocopherol treatment showed no cytotoxicity to normal colon cells CCD-112CoN at the highest concentration and time point tested. RRR-γ-tocopherol treatment resulted in cleavage of PARP, caspase 3, 7, and 8, but not caspase 9. Differences in the percentage cell death and apoptosis were observed in different cell lines suggesting that molecular differences in these cell lines may influence the ability of RRR-γ-tocopherol to induce cell death. Conclusion This is the first study to demonstrate that multiple colon cancer cell lines containing varying genetic alterations will under go growth reduction and apoptosis in the presence of RRR

Polyamine and methionine adenosyltransferase 2A crosstalk in human colon and liver cancer

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Tomasi, Maria Lauda [Division of Gastrointestinal and Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); USC Research Center for Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); The Southern California Research Center for Alcoholic and Pancreatic Diseases and Cirrhosis, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); Ryoo, Minjung; Skay, Anna [Division of Gastrointestinal and Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); USC Research Center for Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); Tomasi, Ivan; Giordano, Pasquale [Department of Colorectal Surgery, Whipps Cross University Hospital, London E11 1NR (United Kingdom); Mato, José M. [CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (Ciberehd), Technology Park of Bizkaia, 48160 Derio, Bizkaia (Spain); Lu, Shelly C., E-mail: shellylu@usc.edu [Division of Gastrointestinal and Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); USC Research Center for Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States); The Southern California Research Center for Alcoholic and Pancreatic Diseases and Cirrhosis, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033 (United States)

2013-07-15

Methionine adenosyltransferase (MAT) is an essential enzyme that is responsible for the biosynthesis of S-adenosylmethionine (SAMe), the principal methyl donor and precursor of polyamines. MAT1A is expressed in normal liver and MAT2A is expressed in all extrahepatic tissues. MAT2A expression is increased in human colon cancer and in colon cancer cells treated with mitogens, whereas silencing MAT2A resulted in apoptosis. The aim of the current work was to examine the mechanism responsible for MAT2A-dependent growth and apoptosis. We found that in RKO (human adenocarcinoma cell line) cells, MAT2A siRNA treatment lowered cellular SAMe and putrescine levels by 70–75%, increased apoptosis and inhibited growth. Putrescine supplementation blunted significantly MAT2A siRNA-induced apoptosis and growth suppression. Putrescine treatment (100 pmol/L) raised MAT2A mRNA level to 4.3-fold of control, increased the expression of c-Jun and c-Fos and binding to an AP-1 site in the human MAT2A promoter and the promoter activity. In human colon cancer specimens, the expression levels of MAT2A, ornithine decarboxylase (ODC), c-Jun and c-Fos are all elevated as compared to adjacent non-tumorous tissues. Overexpression of ODC in RKO cells also raised MAT2A mRNA level and MAT2A promoter activity. ODC and MAT2A are also overexpressed in liver cancer and consistently, similar MAT2A-ODC-putrescine interactions and effects on growth and apoptosis were observed in HepG2 cells. In conclusion, there is a crosstalk between polyamines and MAT2A. Increased MAT2A expression provides more SAMe for polyamines biosynthesis; increased polyamine (putrescine in this case) can activate MAT2A at the transcriptional level. This along with increased ODC expression in cancer all feed forward to further enhance the proliferative capacity of the cancer cell. -- Highlights: • MAT2A knockdown depletes putrescine and leads to apoptosis. • Putrescine attenuates MAT2A knockdown-induced apoptosis and growth

Colonic cell proliferation in normal mucosa of patients with colon cancer

International Nuclear Information System (INIS)

Becciolini, A.; Balzi, M.; Faraoni, P.; Tisti, E.; Thyrion, G.Z.; Giache, V.; Bandettini, L.; Potten, C.S.

1998-01-01

Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), 3 H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns (1) with a high concentration in the bottom fifth of the crypt and (2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt. (orig.)

The Effect of Fucoidan from the Brown Alga Fucus evanescence on the Activity of α-N-Acetylgalactosaminidase of Human Colon Carcinoma Cells.

Science.gov (United States)

Bakunina, Irina; Chadova, Oksana; Malyarenko, Olesya; Ermakova, Svetlana

2018-05-10

α- N -acetylgalactosaminidase (EC 3.2.1.49) (alpha-NaGalase) catalyzes the hydrolysis of N -acetamido-2-deoxy-α-d-galactoside residues from non-reducing ends of various complex carbohydrates and glycoconjugates. It is known that human cancer cells express an alpha-NaGalase, which accumulates in the blood plasma of patients. The enzyme deglycosylates the Gc protein-derived macrophage activating factor (GcMAF) and inhibits macrophage activity acting as an immunosuppressor. The high specific activity 0.033 ± 0.002 μmol mg −1 min −1 of the enzyme was found in human colon carcinoma cells DLD-1. The alpha-NaGalase of DLD-1 cells was isolated and biochemical characterized. The enzyme exhibits maximum activity at pH 5.2 and temperature 55 °C. The K m is 2.15 mM, V max ⁻0.021 μmol min −1 mL −1 , k cat ⁻1.55 min −1 and k cat / K m ⁻0.72 min −1 mM −1 at 37 °C, pH 5.2. The effects of fucoidan from the brown alga Fucus evanescence on the activity of alpha-NaGalase in human colon carcinoma DLD-1 cells and on the biosynthesis of this enzyme were investigated. It was shown that fucoidan did not inhibit free alpha-NaGalase, however, it reduced the expression of the enzyme in the DLD-1 cells at IC 50 73 ± 4 μg mL −1 .

High hRFI expression correlates with resistance to Fluoro pyrimidines in human colon cancer cell lines and in xenografts

International Nuclear Information System (INIS)

Sasaki, S.; Tokyo Univ., Tokyo; Watanabe, T.; Konishi, T.; Kitayama, J.; Nagawa, H.; Kobunai, T.

2005-01-01

We previously reported that the over-expression of hRFI, a protein preferentially expressed in the digestive tract regions of several cancers, exhibited a tendency to inhibit TNF-α induced apoptosis. In this study, we sought to determine the potential effect of hRFI expression on the sensitivity to 5-fluorouracil (5-FU) and/or other fluoro pyrimidines. For the whole lysates of 8 colon cancer cell lines, we performed Western blotting with anti-hRFI antibody and analyzed the correlations between the expression level of hRFI and the cell lines' sensitivity to 5-FU induced apoptosis. Furthermore, for a tissue micro array consisting of 32 xenograft derived human cancer cell lines, we examined the expression levels of hRFI and survivin by immunohistochemical staining, and analyzed the correlations between the expression of each protein and the sensitivity to several chemotherapeutic agents in the xenografts examined. Both in colon cancer cell lines and in xenografts, the expression level of hRFI was correlated with resistance to 5-FU and its derivatives. This evidence suggests that hRFI may be a marker predicting the response to fluorouracil derived chemotherapeutic agents and that the reduction of the expression level of hRFI might improve the outcome of chemotherapy

Colonization and biofilm formation by Staphylococcus aureus on endothelial cell layers under flow

DEFF Research Database (Denmark)

Grønnemose, Rasmus Birkholm; Antoinette Asferg, Cecilie; Kolmos, Hans Jørn

Staphylococcus aureus is a major human pathogen and known for causing vascular infections such as sepsis and infective endocarditis. It has previously been proposed that S. aureus succeed in colonization of the endothelial wall by specific surface attachment likely followed by biofilm formation....... Furthermore, S. aureus is known to invade human cells, which has been proposed to promote persistence through immune and antibiotic evasion. In the current study, we sought to investigate endothelial colonization, invasion, and biofilm formation by S. aureus using a newly developed in vitro flow chamber model....... We show that under physiological shear rates, S. aureus utilizes cellular invasion to enable the following surface colonization and biofilm formation. These observations might help explain the success of S. aureus as a bloodstream pathogen and guide further studies in S. aureus pathogenesis...

BVES regulates EMT in human corneal and colon cancer cells and is silenced via promoter methylation in human colorectal carcinoma.

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Williams, Christopher S; Zhang, Baolin; Smith, J Joshua; Jayagopal, Ashwath; Barrett, Caitlyn W; Pino, Christopher; Russ, Patricia; Presley, Sai H; Peng, DunFa; Rosenblatt, Daniel O; Haselton, Frederick R; Yang, Jin-Long; Washington, M Kay; Chen, Xi; Eschrich, Steven; Yeatman, Timothy J; El-Rifai, Wael; Beauchamp, R Daniel; Chang, Min S

2011-10-01

The acquisition of a mesenchymal phenotype is a critical step in the metastatic progression of epithelial carcinomas. Adherens junctions (AJs) are required for suppressing this epithelial-mesenchymal transition (EMT) but less is known about the role of tight junctions (TJs) in this process. Here, we investigated the functions of blood vessel epicardial substance (BVES, also known as POPDC1 and POP1), an integral membrane protein that regulates TJ formation. BVES was found to be underexpressed in all stages of human colorectal carcinoma (CRC) and in adenomatous polyps, indicating its suppression occurs early in transformation. Similarly, the majority of CRC cell lines tested exhibited decreased BVES expression and promoter DNA hypermethylation, a modification associated with transcriptional silencing. Treatment with a DNA-demethylating agent restored BVES expression in CRC cell lines, indicating that methylation represses BVES expression. Reexpression of BVES in CRC cell lines promoted an epithelial phenotype, featuring decreased proliferation, migration, invasion, and anchorage-independent growth; impaired growth of an orthotopic xenograft; and blocked metastasis. Conversely, interfering with BVES function by expressing a dominant-negative mutant in human corneal epithelial cells induced mesenchymal features. These biological outcomes were associated with changes in AJ and TJ composition and related signaling. Therefore, BVES prevents EMT, and its epigenetic silencing may be an important step in promoting EMT programs during colon carcinogenesis.

3',5'-Cyclic diguanylic acid (c-di-GMP) inhibits basal and growth factor-stimulated human colon cancer cell proliferation

International Nuclear Information System (INIS)

Karaolis, David K.R.; Cheng, Kunrong; Lipsky, Michael; Elnabawi, Ahmed; Catalano, Jennifer; Hyodo, Mamoru; Hayakawa, Yoshihiro; Raufman, Jean-Pierre

2005-01-01

The novel cyclic dinucleotide, 3',5'-cyclic diguanylic acid, cGpGp (c-di-GMP), is a naturally occurring small molecule that regulates important signaling mechanisms in prokaryotes. Recently, we showed that c-di-GMP has 'drug-like' properties and that c-di-GMP treatment might be a useful antimicrobial approach to attenuate the virulence and pathogenesis of Staphylococcus aureus and prevent or treat infection. In the present communication, we report that c-di-GMP (≤50 μM) has striking properties regarding inhibition of cancer cell proliferation in vitro. c-di-GMP inhibits both basal and growth factor (acetylcholine and epidermal growth factor)-induced cell proliferation of human colon cancer (H508) cells. Toxicity studies revealed that exposure of normal rat kidney cells and human neuroblastoma cells to c-di-GMP at biologically relevant doses showed no lethal cytotoxicity. Cyclic dinucleotides, such as c-di-GMP, represent an attractive and novel 'drug-platform technology' that can be used not only to develop new antimicrobial agents, but also to develop novel therapeutic agents to prevent or treat cancer

Increased mRNA expression of a laminin-binding protein in human colon carcinoma: Complete sequence of a full-length cDNA encoding the protein

International Nuclear Information System (INIS)

Yow, Hsiukang; Wong, Jau Min; Chen, Hai Shiene; Lee, C.; Steele, G.D. Jr.; Chen, Lanbo

1988-01-01

Reliable markers to distinguish human colon carcinoma from normal colonic epithelium are needed particularly for poorly differentiated tumors where no useful marker is currently available. To search for markers the authors constructed cDNA libraries from human colon carcinoma cell lines and screened for clones that hybridize to a greater degree with mRNAs of colon carcinomas than with their normal counterparts. Here they report one such cDNA clone that hybridizes with a 1.2-kilobase (kb) mRNA, the level of which is ∼9-fold greater in colon carcinoma than in adjacent normal colonic epithelium. Blot hybridization of total RNA from a variety of human colon carcinoma cell lines shows that the level of this 1.2-kb mRNA in poorly differentiated colon carcinomas is as high as or higher than that in well-differentiated carcinomas. Molecular cloning and complete sequencing of cDNA corresponding to the full-length open reading frame of this 1.2-kb mRNA unexpectedly show it to contain all the partial cDNA sequence encoding 135 amino acid residues previously reported for a human laminin receptor. The deduced amino acid sequence suggests that this putative laminin-binding protein from human colon carcinomas consists of 295 amino acid residues with interesting features. There is an unusual C-terminal 70-amino acid segment, which is trypsin-resistant and highly negatively charged

Traditional Chinese Medicine Curcumin Sensitizes Human Colon Cancer to Radiation by Altering the Expression of DNA Repair-related Genes.

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Yang, Guangen; Qiu, Jianming; Wang, Dong; Tao, Yong; Song, Yihuan; Wang, Hongtao; Tang, Juping; Wang, Xing; Sun, Y U; Yang, Zhijian; Hoffman, Robert M

2018-01-01

The aim of the present study was to investigate the radio-sensitizing efficacy of curcumin, a traditional Chinese medicine (TCM) on colon cancer cells in vitro and in vivo. Human colon cancer HT-29 cells were treated with curcumin (2.5 μM), irradiation (10 Gy) and the combination of irradiation and curcumin. Cell proliferation was assessed using the MTT assay. Apoptotic cells were detected by Annexin V-PE/7-AAD analysis. PCR was performed to determine differential-expression profiling of 95 DNA-repair genes in irradiated cells and cells treated with both irradiation and curcumin. Differentially-expressed genes were confirmed by Western blotting. In vivo radio-sensitizing efficacy of curcumin was assessed in a xenograft mouse model of HT-29 colon cancer. Curcumin was administrated daily by intraperitoneal injection at 20 mg/kg/dose. Mice received irradiation (10 Gy) twice weekly. Apoptosis of the cancer cells following treatment was determined by TUNEL staining. Irradiation induced proliferation inhibition and apoptosis of HT-29 cells in vitro. Concurrent curcumin treatment sensitized the HT-29 tumor to irradiation (pcurcumin and irradiation compared with irradiation alone (pcurcumin and irradiation resulted in a significantly greater tumor-growth inhibition and apoptosis compared to irradiation treatment alone (pCurcumin sensitizes human colon cancer in vitro and in vivo to radiation. Downregulation of LIG4 and PNKP and upregulation of XRCC5 and CCNH DNA-repair-related genes were involved in the radio-sensitizing efficacy of curcumin in colon cancer. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Exosomes from human colorectal cancer induce a tumor-like behavior in colonic mesenchymal stromal cells.

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Lugini, Luana; Valtieri, Mauro; Federici, Cristina; Cecchetti, Serena; Meschini, Stefania; Condello, Maria; Signore, Michele; Fais, Stefano

2016-08-02

Cancer cells, including colorectal cancer ones (CRC), release high amounts of nanovesicles (exosomes), delivering biochemical messages for paracrine or systemic crosstalk. Mesenchymal stromal cells (MSCs) have been shown to play contradicting roles in tumor progression. CRC exosomes induce in cMSCs: i) atypical morphology, higher proliferation, migration and invasion; ii) formation of spheroids; iii) an acidic extracellular environment associated with iv) a plasma membrane redistribution of vacuolar H+-ATPase and increased expression of CEA. Colon cancer derived MSCs, which were isolated from tumor masses, produce umbilicated spheroids, a future frequently observed in the inner core of rapidly growing tumors and recapitulate the changes observed in normal colonic MSCs exposed to CRC exosomes. Tissue specific colonic (c)MSCs were exposed to primary or metastatic CRC exosomes and analysed by light and electron microscopy, proliferation in 2D and 3D cultures, migration and invasion assays, Western blot and confocal microscopy for vacuolar H+-ATPase expression. CRC exosomes are able to induce morphological and functional changes in colonic MSCs, which may favour tumor growth and its malignant progression. Our results suggest that exosomes are actively involved in cancer progression and that inhibiting tumor exosome release may represent a way to interfere with cancer.

Antiproliferative Effects of Tetrabuthylammonium Chloride Ionic Liquid on HCT 8 Human Colon Carcinoma Cells

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Gabi Dumitrescu

2017-05-01

Full Text Available The ionic liquids have attracted a great of attention in the scientific community due to their potential pharmaceutical such as antimicrobial. In this paper, the main objective was the assessment of the cytotoxic effect of tetrabutylammonium chloride against HCT 8 human colon carcinoma cell line. The cells were cultured in 75 cm2 culture flasks  using RPMI medium supplemented with 10% inactivated fetal bovine serum (FBS, penicillin (100 IU/mL and streptomycin (100 μg/mL and maintained at 37 °C and 5% CO2. Before achieving viability test, the cells were harvested using trypsin solution (0.25%. Then, the cells were seeded in 24 – well plates at a density of 5 x 105 cells/mL in 100 µL medium/well in order to reach confluence. After 24 h, the medium was replaced with fresh medium containing different concentrations of ionic liquid, respectively, 0.085, 0.17, 0.34, 0.68 and 1.36 mg /mL. Control group contained cells without treatment. Cell proliferation kinetics have been studied at 24 and 48 h after IL treatment, following trypsinization and counting total cells per plate by using a Trypan blue dye and a hemocytometer. Data obtained from the growth kinetics assay shows that the tetrabutylammonium chloride (TBAC had an inhibitory effect on the growth of cells in a concentration dependent manner. The maximum inhibitory effect on HCT 8 cells it was obtained at 1.36 mg TBAC/mL.

Antiproliferative effect of a novel nitro-oxy derivative of celecoxib in human colon cancer cells: role of COX-2 and nitric oxide.

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Bocca, Claudia; Bozzo, Francesca; Bassignana, Andrea; Miglietta, Antonella

2010-07-01

It has been shown previously that a novel nitrooxy derivative of celecoxib exerts antiproliferative and pro-apoptotic effects in human colon cancer cells. The aim of this study was to elucidate whether these biological properties depend on COX-2 inhibition and/or NO release. Therefore, the derivative was decomposed into the parent compound celecoxib and the NO donor benzyl nitrate and the biological role of each was tested in COX-2-positive (HT-29) and -negative (SW-480) colon cancer cells. The main findings were that the nitro-oxy derivative behaved like celecoxib in HT-29 cells in terms of COX-2 and ERK/MAPK inhibition, as well as induction of apoptosis, while the benzyl nitrate had no such effects. Interestingly, the beta-catenin system was activated by the nitro-oxy derivative as well as by benzyl nitrate alone more potently than by the parent compound celecoxib, suggesting a possible regulatory role for NO. In SW480 cells, these activities were substantially less pronounced, suggesting the presence of COX-2-dependent mechanisms in the modulation of these parameters.

Emigrating Beyond Earth Human Adaptation and Space Colonization

CERN Document Server

Smith, Cameron M

2012-01-01

For four million years humankind has been actively expanding geographically and in doing so has adapted to a wide variety of hostile environments. Now we are looking towards the ultimate adaptation - the colonization of space. Emigrating Beyond Earth illustrates that this is not a technocratic endeavor, but a natural continuation of human evolution; a journey not just for the engineer and rocket scientist, but for everyman. Based on the most current understanding of our universe, human adaptation and evolution, the authors explain why space colonization must be planned as an adaptation to, rather than the conquest of, space. Emigrating Beyond Earth argues that space colonization is an insurance policy for our species, and that it isn't about rockets and robots, it's about humans doing what we've been doing for four million years: finding new places and new ways to live. Applying a unique anthropological approach, the authors outline a framework for continued human space exploration and offer a glimpse of a po...

Human milk lactoferrin inactivates two putative colonization factors expressed by Haemophilus influenzae.

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Qiu, J; Hendrixson, D R; Baker, E N; Murphy, T F; St Geme, J W; Plaut, A G

1998-10-13

Haemophilus influenzae is a major cause of otitis media and other respiratory tract disease in children. The pathogenesis of disease begins with colonization of the upper respiratory mucosa, a process that involves evasion of local immune mechanisms and adherence to epithelial cells. Several studies have demonstrated that human milk is protective against H. influenzae colonization and disease. In the present study, we examined the effect of human milk on the H. influenzae IgA1 protease and Hap adhesin, two autotransported proteins that are presumed to facilitate colonization. Our results demonstrated that human milk lactoferrin efficiently extracted the IgA1 protease preprotein from the bacterial outer membrane. In addition, lactoferrin specifically degraded the Hap adhesin and abolished Hap-mediated adherence. Extraction of IgA1 protease and degradation of Hap were localized to the N-lobe of the bilobed lactoferrin molecule and were inhibited by serine protease inhibitors, suggesting that the lactoferrin N-lobe may contain serine protease activity. Additional experiments revealed no effect of lactoferrin on the H. influenzae P2, P5, and P6 outer-membrane proteins, which are distinguished from IgA1 protease and Hap by the lack of an N-terminal passenger domain or an extracellular linker region. These results suggest that human milk lactoferrin may attenuate the pathogenic potential of H. influenzae by selectively inactivating IgA1 protease and Hap, thereby interfering with colonization. Future studies should examine the therapeutic potential of lactoferrin, perhaps as a supplement in infant formulas.

Antioxidant Activity of Inulin and Its Role in the Prevention of Human Colonic Muscle Cell Impairment Induced by Lipopolysaccharide Mucosal Exposure

Science.gov (United States)

Guarino, Michele Pier Luca; Locato, Vittoria; Cocca, Silvia; Cimini, Sara; Palma, Rossella; Alloni, Rossana; De Gara, Laura; Cicala, Michele

2014-01-01

Background Fructans, such as inulin, are dietary fibers which stimulate gastro-intestinal (GI) function acting as prebiotics. Lipopolysaccharide (LPS) impairs GI motility, through production of reactive oxygen species. The antioxidant activity of various fructans was tested and the protective effect of inulin on colonic smooth muscle cell (SMC) impairment, induced by exposure of human mucosa to LPS, was assessed in an ex vivo experimental model. Methods The antioxidant capacity of fructans was measured in an in vitro system that simulates cooking and digestion processes. Human colonic mucosa and submucosa, obtained from disease-free margins of resected segments for cancer, were sealed between two chambers, with the mucosal side facing upwards with Krebs solution with or without purified LPS from a pathogenic strain of Escherichia coli (O111:B4) and inulin (Frutafit IQ), and the submucosal side facing downwards into Krebs solution. The solutions on the submucosal side were collected following mucosal exposure to Krebs in the absence (N-undernatant) or presence of LPS (LPS-undernatant) or LPS+inulin (LPS+INU-undernatant). Undernatants were tested for their antioxidant activity and the effects on SMCs contractility. Inulin protective effects on mucosa and submucosa layers were assessed measuring the protein oxidation level in the experimental conditions analyzed. Results Antioxidant activity of inulin, which was significantly higher compared to simple sugars, remained unaltered despite cooking and digestion processes. Inulin protected the mucosal and submucosal layers against protein oxidation. Following exposure to LPS-undernatant, a significant decrease in maximal acetylcholine (Ach)-induced contraction was observed when compared to the contraction induced in cells incubated with the N-undernatant (4±1% vs 25±5% respectively, PInulin (35±5%). Conclusions Inulin protects the human colon mucosa from LPS-induced damage and this effect appears to be related to the

Crohn's disease of the colon: ultrastructural changes in submuscular interstitial cells of Cajal

DEFF Research Database (Denmark)

Rumessen, Jüri Johs.; Vanderwinden, Jean-Marie; Horn, Thomas

2011-01-01

of the submuscular plexus were often empty and dilated. Fibroblast-like cells selectively encased macrophages and mast cells. The cytological changes in ICC-SMP in CD are thus similar to changes seen in ulcerative colitis and may be of pathophysiological significance with regard to the motility and sensory......Interstitial cells of Cajal (ICC) at the submuscular border of the human colon (ICC-SMP) are the proposed pacemaker cells of the musculature. In patients with Crohn's disease (CD) of the colon, ICC-SMP showed characteristic cytological changes from controls. The changes comprised secondary...... lysosomes in connection with lipid droplets and cytoplasmic vacuoles or multiple empty, confluent and often outbulging vacuoles merging with cisterns of granular endoplasmic reticulum and clusters of glycogen granules. These changes were most pronounced in patients with macroscopical mucosal inflammation...

Multifaceted Interpretation of Colon Cancer Stem Cells.

Science.gov (United States)

Hatano, Yuichiro; Fukuda, Shinya; Hisamatsu, Kenji; Hirata, Akihiro; Hara, Akira; Tomita, Hiroyuki

2017-07-05

Colon cancer is one of the leading causes of cancer-related deaths worldwide, despite recent advances in clinical oncology. Accumulating evidence sheds light on the existence of cancer stem cells and their role in conferring therapeutic resistance. Cancer stem cells are a minor fraction of cancer cells, which enable tumor heterogeneity and initiate tumor formation. In addition, these cells are resistant to various cytotoxic factors. Therefore, elimination of cancer stem cells is difficult but essential to cure the malignant foci completely. Herein, we review the recent evidence for intestinal stem cells and colon cancer stem cells, methods to detect the tumor-initiating cells, and clinical significance of cancer stem cell markers. We also describe the emerging problems of cancer stem cell theory, including bidirectional conversion and intertumoral heterogeneity of stem cell phenotype.

GM-CSF produced by non-hematopoietic cells is required for early epithelial cell proliferation and repair of injured colonic mucosa1,2

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Egea, Laia; McAllister, Christopher S.; Lakhdari, Omar; Minev, Ivelina; Shenouda, Steve; Kagnoff, Martin F.

2012-01-01

GM-CSF is a growth factor that promotes the survival and activation of macrophages and granulocytes, and dendritic cell (DC) differentiation and survival in vitro. The mechanism by which exogenous GM-CSF ameliorates the severity of Crohn’s disease in humans and colitis in murine models has been considered mainly to reflect its activity on myeloid cells. We used GM-CSF deficient (GM-CSF−/−) mice to probe the functional role of endogenous host-produced GM-CSF in a colitis model induced after injury to the colon epithelium. Dextran sodium sulfate (DSS) at doses that resulted in little epithelial damage and mucosal ulceration in wild type (WT) mice resulted in marked colon ulceration and delayed ulcer healing in GM-CSF−/− mice. Colon crypt epithelial cell proliferation in vivo was significantly decreased in GM-CSF−/− mice at early times after DSS injury. This was paralleled by decreased expression of crypt epithelial cell genes involved in cell cycle, proliferation, and wound healing. Decreased crypt cell proliferation and delayed ulcer healing in GM-CSF−/− mice were rescued by exogenous GM-CSF, indicating the lack of a developmental abnormality in the epithelial cell proliferative response in those mice. Non-hematopoietic cells and not myeloid cells produced the GM-CSF important for colon epithelial proliferation after DSS-induced injury as revealed by bone marrow chimera and DC depletion experiments, with colon epithelial cells being the cellular source of GM-CSF. Endogenous epithelial cell produced GM-CSF has a novel non-redundant role in facilitating epithelial cell proliferation and ulcer healing in response to injury of the colon crypt epithelium. PMID:23325885

Monoterpene bisindole alkaloids, from the African medicinal plant Tabernaemontana elegans, induce apoptosis in HCT116 human colon carcinoma cells.

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Mansoor, Tayyab A; Borralho, Pedro M; Dewanjee, Saikat; Mulhovo, Silva; Rodrigues, Cecília M P; Ferreira, Maria-José U

2013-09-16

Tabernaemontana elegans is a medicinal plant used in African traditional medicine to treat several ailments including cancer. The aims of the present study were to identify anti-cancer compounds, namely apoptosis inducers, from Tabernaemontana elegans, and hence to validate its usage in traditional medicine. Six alkaloids, including four monomeric indole (1-3, and 6) and two bisindole (4 and 5) alkaloids, were isolated from the methanolic extract of Tabernaemontana elegans roots. The structures of these compounds were characterized by 1D and 2D NMR spectroscopic and mass spectrometric data. Compounds 1-6 along with compound 7, previously isolated from the leaves of the same species, were evaluated for in vitro cytotoxicity against HCT116 human colon carcinoma cells by the MTS metabolism assay. The cytotoxicity of the most promising compounds was corroborated by Guava-ViaCount flow cytometry assays. Selected compounds were next studied for apoptosis induction activity in HCT116 cells, by evaluation of nuclear morphology following Hoechst staining, and by caspase-3 like activity assays. Among the tested compounds (1-7), the bisindole alkaloids tabernaelegantine C (4) and tabernaelegantinine B (5) were found to be cytotoxic to HCT116 cells at 20 µM, with compound 5 being more cytotoxic than the positive control 5-Fluorouracil (5-FU), at a similar dose. In fact, even at 0.5 µM, compound 5 was more potent than 5-FU. Compounds 4 and 5 induced characteristic patterns of apoptosis in HCT116 cancer cells including, cell shrinkage, condensation, fragmentation of the nucleus, blebbing of the plasma membrane and chromatin condensation. Further, general caspase-3-like activity was increased in cells exposed to compounds 4 and 5, corroborating the nuclear morphology evaluation assays. Bisindole alkaloids tabernaelegantine C (4) and tabernaelegantinine B (5) were characterized as potent apoptosis inducers in HCT116 human colon carcinoma cells and as possible lead/scaffolds for

Malignant transformation of human colon epithelial cells by benzo[c]phenanthrene dihydrodiolepoxides as well as 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine

International Nuclear Information System (INIS)

Herbst, Uta; Fuchs, Judith Iris; Teubner, Wera; Steinberg, Pablo

2006-01-01

Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HCAs) ingested with food have repeatedly been suggested to be involved in the malignant transformation of colon epithelial cells. In order to test this hypothesis, HCEC cells (SV40 large T antigen-immortalized human colon epithelial cells) were incubated with a racemic mixture of benzo[c]phenanthrene dihydrodiol epoxides (B[c]PhDE), extremely potent carcinogenic PAH metabolites in vivo, or with 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine (N-OH-PhIP), the N-hydroxylated metabolite of the most abundant HCA in cooked meat. First, it was shown that HCEC cells express sulfotransferase 1A1, which is needed to metabolize N-OH-PhIP to the corresponding N-sulfonyloxy derivative, the direct precursor molecule of genotoxic nitrenium ions. Thereafter, exponentially growing HCEC cells were exposed five times to 0.1 μg (0.37 nmol) B[c]PhDE/ml for 30 min or 0.72 μg (3 nmol) N-OH-PhIP/ml for 24 h. Chemically treated HCEC cells showed an enhanced saturation density and grew faster than the corresponding solvent-treated cell cultures. After five treatment cycles, HCEC B[c]PhDE as well as HCEC N-OH-PhIP cells lost cell-cell contact inhibition and started piling up and forming foci in the culture flasks. Furthermore, HCEC B[c]PhDE and HCEC N-OH-PhIP cells were injected i.m. into SCID mice. Within 6 weeks after injection, eight animals out of eight injected with HCEC B[c]PhDE or HCEC N-OH-PhIP cells developed tumors at the site of injection, thus demonstrating the high tumorigenic potential of the HCEC B[c]PhDE and HCEC N-OH-PhIP cell cultures. Taken together, we show for the first time that the abovementioned active PAH metabolites as well as N-OH-PhIP are indeed able to malignantly transform human colon epithelial cells in vitro

Colon carcinogenesis: influence of Western diet-induced obesity and targeting stem cells using dietary bioactive compounds.

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Kasdagly, Maria; Radhakrishnan, Sridhar; Reddivari, Lavanya; Veeramachaneni, D N Rao; Vanamala, Jairam

2014-01-01

Colon cancer strikes more than 1 million people annually and is responsible for more than 500,000 cancer deaths worldwide. Recent evidence suggests that the majority of malignancies, including colon cancer are driven by cancer stem cells (CSCs) that are resistant to current chemotherapeutic approaches leading to cancer relapse. Wnt signaling plays a critical role in colon stem cell renewal and carcinogenesis. Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), a Wnt target gene, and aldehyde dehydrogenase 1 B1 (ALDH1B1) are good markers for normal and malignant human colon stem cells. Diet contributes to 20% to 42% of all human cancers and 50% to 90% of colon cancer. Recent evidence shows that the Western diet has a causative link to colon cancer; however, mechanisms of action are not fully elucidated. Western diet-induced obesity elevates systemic insulin-like growth factor-1 and insulin levels, which could lead to elevated proliferation and suppressed apoptosis of CSCs through PI3K/AKT/Wnt pathway. Although conventional chemotherapy targets the PI3K/AKT pathways and can significantly reduce tumor size, it fails to eliminate CSCs and has serious side effects. Dietary bioactive compounds such as grape seed extract, curcumin, lycopene, and resveratrol have promising chemopreventive effects, without serious side effects on various types of cancers due to their direct and indirect actions on CSC self-renewal pathways such as the Wnt pathway. Understanding the role of CSCs in diet-induced colon cancer will aid in development of evidence-based dietary chemopreventive strategies and/or therapeutic agents targeting CSCs. Copyright © 2014 Elsevier Inc. All rights reserved.

Cell surface response of chemically transformed, malignant mouse embryonal fibroblasts and human colon cancer cells to the maturation-promoting agent, N,N-dimethylformamide

International Nuclear Information System (INIS)

Marks, M.E.

1985-01-01

The lactoperoxidase/ 125 I radioiodination procedure was used to probe the cell surface of normal, nontransformed AKR-2B mouse embryo fibroblasts and malignant, permanently methylcholanthrene-transformed AKR-2B (AKR-MCA) cells to establish the relationship between cell surface changes and transformation/differentiation in this call system. AKR-MCA cells displayed surface alterations secondary to N,N-dimethylformamide (DFM)-promoted differentiation. Growth of AKR-MCA cells in DMF virtually eliminated the 85,000 and 63,000 molecular weight surface proteins susceptible to radioiodination and increased surface material of ∼200,000 molecular weight. Thus, surface profiles of DFM-treated AKR-MCA cells were essentially identical to those of nontransformed AKR-2B cells. Experimentation was extended to a cultured human colon cancer cell line (HCT MOSER). HCT MOSER cells exposed to DMF manifested marked, reversible morphological and surface changes which occurred as a function of time of growth in DMF and DMF concentration. Interestingly, material reactive with anti-fibronectin was found on the surfaces and in the culture medium of DFM-treated HCT MOSER cells

Osteopontin mediates Citrobacter rodentium-induced colonic epithelial cell hyperplasia and attaching-effacing lesions.

Science.gov (United States)

Wine, Eytan; Shen-Tu, Grace; Gareau, Mélanie G; Goldberg, Harvey A; Licht, Christoph; Ngan, Bo-Yee; Sorensen, Esben S; Greenaway, James; Sodek, Jaro; Zohar, Ron; Sherman, Philip M

2010-09-01

Although osteopontin (OPN) is up-regulated in inflammatory bowel diseases, its role in disease pathogenesis remains controversial. The objective of this study was to determine the role of OPN in host responses to a non-invasive bacterial pathogen, Citrobacter rodentium, which serves as a murine infectious model of colitis. OPN gene knockout and wild-type mice were infected orogastrically with either C. rodentium or Luria-Bertani (LB) broth. Mouse-derived OPN(+/+) and OPN(-/-) fibroblasts were incubated with C. rodentium and attaching-effacing lesions were demonstrated using transmission electron microscopy and immunofluorescence. Colonic expression of OPN was increased by C. rodentium infection of wild-type mice. Furthermore, colonic epithelial cell hyperplasia, the hallmark of C. rodentium infection, was reduced in OPN(-/-) mice, and spleen enlargement by infection was absent in OPN(-/-) mice. Rectal administration of OPN to OPN(-/-) mice restored these effects. There was an 8- to 17-fold reduction in bacterial colonization in OPN(-/-) mice, compared with wild-type mice, which was accompanied by reduced attaching-effacing lesions, both in infected OPN(-/-) mice and OPN(-/-) mouse fibroblasts. Moreover, adhesion pedestals were restored in OPN(-/-) cells complemented with human OPN. Therefore, lack of OPN results in decreased pedestal formation, colonization, and colonic epithelial cell hyperplasia responses to C. rodentium infection, indicating that OPN impacts disease pathogenesis through bacterial attachment and altered host immune responses.

Effects of airborne particulate matter on alternative pre-mRNA splicing in colon cancer cells

Energy Technology Data Exchange (ETDEWEB)

Buggiano, Valeria; Petrillo, Ezequiel; Alló, Mariano; Lafaille, Celina [Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires (Argentina); Redal, María Ana [Instituto de Ciencias Básicas y Medicina Experimental, Hospital Italiano de Buenos Aires (Argentina); Alghamdi, Mansour A. [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia); Khoder, Mamdouh I. [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia); Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah (Saudi Arabia); Shamy, Magdy [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia); Muñoz, Manuel J., E-mail: mmunoz@fbmc.fcen.uba.ar [Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires (Argentina); and others

2015-07-15

Alternative pre-mRNA splicing plays key roles in determining tissue- and species-specific cell differentiation as well as in the onset of hereditary disease and cancer, being controlled by multiple post- and co-transcriptional regulatory mechanisms. We report here that airborne particulate matter, resulting from industrial pollution, inhibits expression and specifically affects alternative splicing at the 5′ untranslated region of the mRNA encoding the bone morphogenetic protein BMP4 in human colon cells in culture. These effects are consistent with a previously reported role for BMP4 in preventing colon cancer development, suggesting that ingestion of particulate matter could contribute to the onset of colon cell proliferation. We also show that the underlying mechanism might involve changes in transcriptional elongation. This is the first study to demonstrate that particulate matter causes non-pleiotropic changes in alternative splicing. - Highlights: • Airborne particulate matter (PM10) affects alternative splicing in colon cells. • PM10 upregulates one of the two mRNA variants of the growth factor BMP-4. • This variant has a longer 5′ unstranslated region and introduces an upstream AUG. • By regulating BMP-4 mRNA splicing PM10 inhibits total expression of BMP-4 protein. • BMP-4 downregulation was previously reported to be associated to colon cancer.

Identification of a Novel Substance P–Neurokinin-1 Receptor MicroRNA-221-5p Inflammatory Network in Human Colonic Epithelial CellsSummary

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Kai Fang

2015-09-01

Full Text Available Background & Aims: Substance P (SP, a neuropeptide member of the tachykinin family, plays a critical role in colitis. MicroRNAs (miRNAs are small noncoding RNAs that negatively regulate gene expression. We examined whether SP modulates expression of microRNAs in human colonic epithelial cells. Methods: We performed microRNA profiling analysis of SP-stimulated human colonic epithelial NCM460 cells overexpressing neurokinin-1 receptor (NCM460-NK-1R. Targets of SP-regulated microRNAs were validated by real-time polymerase chain reaction (RT-PCR. Functions of miRNAs were tested in NCM460-NK-1R cells and the trinitrobenzene sulfonic acid (TNBS and dextran sulfate sodium (DSS models of colitis. Results: SP stimulated differential expression of 29 microRNAs, including miR-221-5p, the highest up-regulated miR (by 12.6-fold upon SP stimulation. Bioinformatic and luciferase reporter analyses identified interleukin-6 receptor (IL-6R mRNA as a direct target of miR-221-5p in NCM460 cells. Accordingly, SP exposure of NCM460-NK-1R cells increased IL-6R mRNA expression, and overexpression of miR-221-5p reduced IL-6R expression. Nuclear factor κB and c-Jun N-terminal kinase inhibition decreased SP-induced miR-221-5p expression. MiR-221-5p expression was increased in both TNBS- and DSS-induced colitis and in colonic biopsy samples from ulcerative colitis but not Crohn’s disease patients compared with controls. In mice, intracolonic administration of a miR-221-5p chemical inhibitor exacerbated TNBS- and DSS-induced colitis and increased colonic tumor necrosis factor-α, C-X-C motif chemokine 10 (Cxcl10, and collagen, type II, α 1 (Col2α1 mRNA expression. In situ hybridization in TNBS- and DSS-exposed colons revealed increased miR-221-5p expression primarily in colonocytes. Conclusions: Our results reveal a novel NK-1R-miR-221-5p-IL-6R network that protects from colitis. The use of miR-221-5p mimics may be a promising approach for colitis

An ultrastructural study of the effect of neomycin on the colon in the human subject and in the conventional and the germ-free mouse.

Science.gov (United States)

Aluwihare, A P

1971-05-01

An electron microscopic study of the colon of normal mice and human subjects and those treated with neomycin is reported; there is a close resemblance between the mouse and human colons. After rapid disinfection of the colon, there is epithelial cell damage due to a toxic effect of the drug, a reduction in epithelial turnover accompanying the change in flora, and an important reduction in the cellularity of the lamina propria mainly due to a reduction in inflammatory cells. The changes in the lamina propria probably represent changes in the antipathogenetic defences of the host.

Silencing of the hTERT gene by shRNA inhibits colon cancer SW480 cell growth in vitro and in vivo.

Directory of Open Access Journals (Sweden)

Ai-Qun Liu

Full Text Available Human telomerase reverse transcriptase (hTERT is the key enzyme responsible for synthesizing and maintaining the telomeres on the ends of chromosomes, and it is essential for cell proliferation. This has made hTERT a focus of oncology research and an attractive target for anticancer drug development. In this study, we designed a small interfering RNA (siRNA targeting the catalytic subunit of hTERT and tested its effects on the growth of telomerase-positive human colon carcinoma SW480 cells in vitro, as well as on the tumorigenicity of these cells in nude mice. Transient and stable transfection of hTERT siRNA into colon cancer SW480 cells suppressed hTERT expression, reduced telomerase activity and inhibited cell growth and proliferation. Knocking down hTERT expression in SW480 tumors xenografted into nude mice significantly slowed tumor growth and promoted tumor cell apoptosis. Our results suggest that hTERT is involved in carcinogenesis of human colon carcinoma, and they highlight the therapeutic potential of a hTERT knock-down approach.

Resveratrol suppresses IGF-1 induced human colon cancer cell proliferation and elevates apoptosis via suppression of IGF-1R/Wnt and activation of p53 signaling pathways

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Radhakrishnan Sridhar

2010-05-01

Full Text Available Abstract Background Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene, a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. Methods We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. Results Resveratrol (100-150 μM exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G0/G1-S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. Conclusions For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and

Resveratrol suppresses IGF-1 induced human colon cancer cell proliferation and elevates apoptosis via suppression of IGF-1R/Wnt and activation of p53 signaling pathways

International Nuclear Information System (INIS)

Vanamala, Jairam; Reddivari, Lavanya; Radhakrishnan, Sridhar; Tarver, Chris

2010-01-01

Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene), a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity) and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. Resveratrol (100-150 μM) exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G 0 /G 1 -S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and activation of p53, suggesting its potential role as a

microRNA-143 down-regulates Hexokinase 2 in colon cancer cells

DEFF Research Database (Denmark)

Gregersen, Lea Haarup; Jacobsen, Anders; Frankel, Lisa

2012-01-01

a significant enrichment of miR-143 seed sites in their 3' UTRs. Here we report the identification of Hexokinase 2 (HK2) as a direct target of miR-143. We show that re-introduction of miR-143 in the colon cancer cell line DLD-1 results in a decreased lactate secretion. CONCLUSION: We have identified...... and validated HK2 as a miR-143 target. Furthermore, our results indicate that miR-143 mediated down-regulation of HK2 affects glucose metabolism in colon cancer cells. We hypothesize that loss of miR-143-mediated repression of HK2 can promote glucose metabolism in cancer cells, contributing to the shift towards......ABSTRACT: BACKGROUND: MicroRNAs (miRNAs) are well recognized as gene regulators and have been implicated in the regulation of development as well as human diseases. miR-143 is located at a fragile site on chromosome 5 frequently deleted in cancer, and has been reported to be down...

Deoxycholic acid and selenium metabolite methylselenol exert common and distinct effects on cell cycle, apoptosis, and MAP kinase pathway in HCT116 human colon cancer cells.

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Zeng, Huawei; Botnen, James H; Briske-Anderson, Mary

2010-01-01

The cell growth inhibition induced by bile acid deoxycholic acid (DCA) may cause compensatory hyperproliferation of colonic epithelial cells and consequently increase colon cancer risk. On the other hand, there is increasing evidence for the efficacy of certain forms of selenium (Se) as anticancer nutrients. Methylselenol has been hypothesized to be a critical Se metabolite for anticancer activity in vivo. In this study, we demonstrated that both DCA (75-300 micromol/l) and submicromolar methylselenol inhibited colon cancer cell proliferation by up to 64% and 63%, respectively. In addition, DCA and methylselenol each increased colon cancer cell apoptosis rate by up to twofold. Cell cycle analyses revealed that DCA induced an increase in only the G1 fraction with a concomitant drop in G2 and S-phase; in contrast, methylselenol led to an increase in the G1 and G2 fractions with a concomitant drop only in the S-phase. Although both DCA and methylselenol significantly promoted apoptosis and inhibited cell growth, examination of mitogen-activated protein kinase (MAPK) pathway activation showed that DCA, but not methylselenol, induced SAPK/JNK1/2, p38 MAPK, ERK1/2 activation. Thus, our data provide, for the first time, the molecular basis for opposite effects of methylselenol and DCA on colon tumorigenesis.

Titanium dioxide nanoparticles activate IL8-related inflammatory pathways in human colonic epithelial Caco-2 cells

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Krüger, Kristin; Cossais, François; Neve, Horst; Klempt, Martin

2014-05-01

Nanosized titanium dioxide (TiO2) particles are widely used as food additive or coating material in products of the food and pharmaceutical industry. Studies on various cell lines have shown that TiO2 nanoparticles (NPs) induced the inflammatory response and cytotoxicity. However, the influences of TiO2 NPs' exposure on inflammatory pathways in intestinal epithelial cells and their differentiation have not been investigated so far. This study demonstrates that TiO2 NPs with particle sizes ranging between 5 and 10 nm do not affect enterocyte differentiation but cause an activation of inflammatory pathways in the human colon adenocarcinoma cell line Caco-2. 5 and 10 nm NPs' exposures transiently induce the expression of ICAM1, CCL20, COX2 and IL8, as determined by quantitative PCR, whereas larger particles (490 nm) do not. Further, using nuclear factor (NF)-κB reporter gene assays, we show that NP-induced IL8 mRNA expression occurs, in part, through activation of NF-κB and p38 mitogen-activated protein kinase pathways.

Inhibitory Effects of Probiotic Lactobacillus on the Growth of Human Colonic Carcinoma Cell Line HT-29.

Science.gov (United States)

Chen, Zhung-Yuan; Hsieh, You-Miin; Huang, Chun-Chih; Tsai, Cheng-Chih

2017-01-10

This study was conducted to investigate the inhibitory effect of Lactobacillus cells and supernatants on the growth of the human colon cancer cell line HT-29. Our study results indicated that the PM153 strain exhibits the best adhesion ability and the highest survival in the gastrointestinal tract simulation experiment. Furthermore, after an 8-h co-culture of PM153 and HT-29 cells, the PM153 strain can induce the secretion of nitric oxide from the HT-29 cells. In addition, after the co-culture of the BCRC17010 strain (10⁸ cfu/mL) and HT-29 cells, the Bax/Bcl-2 ratio in the HT-29 cells was 1.19, which showed a significant difference from the other control and LAB groups ( p strain exerts a pro-apoptotic effect on the HT-29 cells. Upon co-culture with HT-29 cells for 4, 8 and 12 h, the BCRC14625 strain (10⁸ cfu/mL) demonstrated a significant increase in lactate dehydrogenase (LDH) activity ( p strains have ability to inhibit the growth of the colorectal cancer cell line HT-29 Bax/Bcl-2 pathway or NO production. In summary, we demonstrated that the BCRC17010 strain, good abilities of adhesion and increased LDH release, was the best probiotic potential for inhibition of HT-29 growth amongst the seven LAB strains tested in vitro.

Deoxynivalenol (DON) is toxic to human colonic, lung and monocytic cell lines, but does not increase the IgE response in a mouse model for allergy

International Nuclear Information System (INIS)

Instanes, Christine; Hetland, Geir

2004-01-01

We examined whether the common crop mycotoxin deoxynivalenol (DON) from Fusarium species is toxic to human colonic (Caco-2), lung (A549) and monocytic (U937) cell lines. Moreover, since DON reportedly induces increased levels of Th2 cytokines and total IgE, and we have observed that mould extracts adjuvated allergy development in mice, possible adjuvant effect of DON on allergy was studied in a mouse model. For all the cells, exposure to DON for 24 h reduced cellular protein synthesis, proliferation and survival rate dose-dependently. In addition, production of IL-8 in the U937 cell line increased up to eight-fold at levels of DON just lower than the most toxic one, suggesting that IL-8 can be used as an additional index for cytotoxicity in mononuclear phagocytes. However, DON did not increase levels of allergen-specific IgE or IgG1 in the mouse model for allergy. These results suggest that DON, when inhaled or ingested, may have toxic effect on human alveolar macrophages and epithelial cells in lungs and colon, but does not increase the allergic response to allergens

How dysregulated colonic crypt dynamics cause stem cell overpopulation and initiate colon cancer.

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Boman, Bruce M; Fields, Jeremy Z; Cavanaugh, Kenneth L; Guetter, Arthur; Runquist, Olaf A

2008-05-01

Based on investigation of the earliest colonic tissue alteration in familial adenomatous polyposis (FAP) patients, we present the hypothesis that initiation of colorectal cancer by adenomatous polyposis coli (APC) mutation is mediated by dysregulation of two cellular mechanisms. One involves differentiation, which normally decreases the proportion (proliferative fraction) of colonic crypt cells that can proliferate; the other is a cell cycle mechanism that simultaneously increases the probability that proliferative cells are in S phase. In normal crypts, stem cells (SC) at the crypt bottom generate rapidly proliferating cells, which undergo differentiation while migrating up the crypt. Our modeling of normal crypts suggests that these transitions are mediated by mechanisms that regulate proliferative fraction and S-phase probability. In FAP crypts, the population of rapidly proliferating cells is shifted upwards, as indicated by the labeling index (LI; i.e., crypt distribution of cells in S phase). Our analysis of FAP indicates that these transitions are delayed because the proliferative fraction and S-phase probability change more slowly as a function of crypt level. This leads to expansion of the proliferative cell population, including a subpopulation that has a low frequency of S-phase cells. We previously reported that crypt SC overpopulation explains the LI shift. Here, we determine that SCs (or cells having high stemness) are proliferative cells with a low probability of being in S phase. Thus, dysregulation of mechanisms that control proliferative fraction and S-phase probability explains how APC mutations induce SC overpopulation at the crypt bottom, shift the rapidly proliferating cell population upwards, and initiate colon tumorigenesis.

Musa paradisiaca inflorescence induces human colon cancer cell death by modulating cascades of transcriptional events.

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K B, Arun; Madhavan, Aravind; T R, Reshmitha; Thomas, Sithara; Nisha, P

2018-01-24

Colorectal cancer (CRC) is one of the leading causes of cancer death, and diet plays an important role in the etiology of CRC. Traditional medical practitioners in many South Asian countries use plantain inflorescence to treat various gastro-intestinal ailments. The aim of the present study was to investigate the anticancer effects of extracts of inflorescence of Musa paradisiaca against HT29 human colon cancer cells and elucidate the mechanism of these effects by studying the modulation of cascades of transcriptional events. In vitro assays depicted that methanol extract of Musa paradisiaca inflorescence (PIMET) was cytotoxic to HT29 cells. PIMET induced DNA damage and arrested the cell cycle at the G2/M phase. Expression studies showed that PIMET pretreatment upregulates pro-apoptotic Bcl2 and downregulates anti-apoptotic Bax proteins. Different assays showed that the deregulation of pro/antiapoptotic proteins reduces the mitochondrial membrane potential and ATP production; moreover, it enhances cytochrome c release, which triggers the apoptotic pathway, and further cleaves caspase 3 and PARP proteins, resulting in apoptosis. Changes in the protein expression profile of HT29 cells after PIMET treatment were analyzed using mass-spectrometry-based proteomics. PIMET treatment significantly altered the expression of HT29 protein; interestingly, X-linked inhibitor of apoptosis protein was also downregulated. Alteration in the expression of this protein has significant effects, leading to HT29 cell death.

Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

LENUS (Irish Health Repository)

Alzamora, Rodrigo

2011-01-01

Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 ± 8 μM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCα and PKA, but had no effect on p42\\/p44 MAPK and PKCδ. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE (∼65%), an inhibitor of PKCα and to a smaller extent by inhibition of p38 MAPK with SB202190 (∼15%). Berberine treatment induced an increase in association between PKCα and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCα-dependent pathway.

Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

LENUS (Irish Health Repository)

Alzamora, Rodrigo

2012-02-01

Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 +\\/- 8 muM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCalpha and PKA, but had no effect on p42\\/p44 MAPK and PKCdelta. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE ( approximately 65%), an inhibitor of PKCalpha and to a smaller extent by inhibition of p38 MAPK with SB202190 ( approximately 15%). Berberine treatment induced an increase in association between PKCalpha and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCalpha-dependent pathway.

Serological analysis of human anti-human antibody responses in colon cancer patients treated with repeated doses of humanized monoclonal antibody A33.

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Ritter, G; Cohen, L S; Williams, C; Richards, E C; Old, L J; Welt, S

2001-09-15

Mouse monoclonal antibody A33 (mAb A33) recognizes a M(r) 43,000 cell surface glycoprotein (designated A33) expressed in human colonic epithelium and colon cancer but absent from most other normal tissues. In patients, mAb A33 localizes with high specificity to colon cancer and is retained for up to 6 weeks in the cancer but cleared rapidly from normal colon (5-6 days). As a carrier of (125)I or (131)I, mAb A33 has shown antitumor activity. Induction of strong human anti-mouse antibody (immunoglobulin; HAMA) responses in patients, however, limits the use of the murine mAb A33 to very few injections. A humanized version of this antibody (huAb A33) has been prepared for Phase I and II clinical studies in patients with colon cancer. In those studies, immunogenicity of huAb A33 has been monitored using a novel, highly sensitive BIACORE method, which allows measurement of human anti-human antibodies (HAHAs) without the use of secondary reagents. We found that 63% (26 of 41) of the patients treated with repeated doses of huAb A33 developed HAHAs against a conformational antigenic determinant located in the V(L) and V(H) regions of huAb A33. Detailed serological analysis showed two distinct types of HAHAs. HAHA of type I (49% of patients) was characterized by an early onset with peak HAHA levels after 2 weeks of treatment, which declined with ongoing huAb A33 treatment. HAHA of type II (17% of patients) was characterized by a typically later onset of HAHA than in type I and by progressively increasing HAHA levels with each subsequent huAb A33 administration. Colon cancer patients with type I HAHAs did not develop infusion-related adverse events. In contrast, HAHA of type II was indicative of infusion-related adverse events. By using this new method, we were able to distinguish these two types of HAHAs in patients while on antibody treatment, allowing patients to be removed from study prior to the onset of severe infusion-related adverse events.

Arctigenin induces apoptosis in colon cancer cells through ROS/p38MAPK pathway.

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Li, Qing-chun; Liang, Yun; Tian, Yuan; Hu, Guang-rui

2016-01-01

In the current study the antiproliferative effect of arctigenin, plant lignin, was evaluated on human colon cancer cell line HT-29. Furthermore, attempts were made to explore the signaling mechanism which may be responsible for its effect. Cell growth inhibition was assessed by MTT and LDH assays. Flow cytometric analysis was performed to determine cell arrest in the cell cycle phase and apoptosis. Furthermore, to confirm the apoptotic activity of arctigenin, caspase-9 and -3 activities analysis was performed. The levels of reactive oxygen species (ROS) and p38 mitogen activated protein kinase (MAPK) were investigated to determine their role in inducing apoptosis in arctigenin-treated HT-29 colon cancer cell line. MTT and LDH results demonstrated significant cell growth inhibitory effect of arctigenin on HT-29 cells in a dose-dependent manner. Furthermore, increase in cell number arrested at G2/M phase was observed in flow cytometric analysis upon arctigenin treatment. In addition, arctigenin increased the apoptotic ratio in a dose-dependent manner. The involvement of intrinsic apoptotic pathway was indicated by the activation of caspase-9 and -3. Moreover, increased ROS production, activation of p38 MAPK and changes in mitochondrial membrane potential (ΔΨm) also revealed the role of intrinsic apoptotic signaling pathway in cell growth inhibition after arctigenin exposure. Arctigenin induces apoptosis in HT-29 colon cancer cells by regulating ROS and p38 MAPK pathways.

PPARδ deficiency disrupts hypoxia-mediated tumorigenic potential of colon cancer cells.

Science.gov (United States)

Jeong, Eunshil; Koo, Jung Eun; Yeon, Sang Hyeon; Kwak, Mi-Kyoung; Hwang, Daniel H; Lee, Joo Young

2014-11-01

Peroxisome proliferator-activated receptor (PPAR) δ is highly expressed in colon epithelial cells and closely linked to colon carcinogenesis. However, the role of PPARδ in colon cancer cells in a hypoxic tumor microenvironment is not fully understood. We found that expression of the tumor-promoting cytokines, IL-8 and VEGF, induced by hypoxia (colon cancer cells. Consequently, PPARδ-knockout colon cancer cells exposed to hypoxia and deferoxamine failed to stimulate endothelial cell vascularization and macrophage migration/proliferation, whereas wild-type cells were able to induce angiogenesis and macrophage activation in response to hypoxic stress. Hypoxic stress induced transcriptional activation of PPARδ, but not its protein expression, in HCT116 cells. Exogenous expression of p300 potentiated deferoxamine-induced PPARδ transactivation, while siRNA knockdown of p300 abolished hypoxia- and deferoxamine-induced PPARδ transactivation. PPARδ associated with p300 upon hypoxic stress as demonstrated by coimmunoprecipitation studies. PI3K inhibitors or siRNA knockdown of Akt suppressed the PPARδ transactivation induced by hypoxia and deferoxamine in HCT116 cells, leading to decreased expression of IL-8 and VEGF. Collectively, these results reveal that PPARδ is required for hypoxic stress-mediated cytokine expression in colon cancer cells, resulting in promotion of angiogenesis, macrophage recruitment, and macrophage proliferation in the tumor microenvironment. p300 and the PI3K/Akt pathway play a role in the regulation of PPARδ transactivation induced by hypoxic stress. Our results demonstrate the positive crosstalk between PPARδ in tumor cells and the hypoxic tumor microenvironment and provide potential therapeutic targets for colon cancer. © 2014 Wiley Periodicals, Inc.

Impact of Mesenchymal Stem Cell secreted PAI-1 on colon cancer cell migration and proliferation

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Hogan, Niamh M. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Joyce, Myles R. [Department of Colorectal Surgery, University College Hospital, Galway (Ireland); Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy [Regenerative Medicine Institute, National University of Ireland, Galway (Ireland); Kerin, Michael J. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Dwyer, Roisin M., E-mail: roisin.dwyer@nuigalway.ie [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland)

2013-06-14

Highlights: •MSCs were directly co-cultured with colorectal cancer (CRC) cells on 3D scaffolds. •MSCs influence CRC protein/gene expression, proliferation and migration. •We report a significant functional role of MSC-secreted PAI-1 in colon cancer. -- Abstract: Mesenchymal Stem Cells are known to engraft and integrate into the architecture of colorectal tumours, with little known regarding their fate following engraftment. This study aimed to investigate mediators of Mesenchymal Stem Cell (MSC) and colon cancer cell (CCC) interactions. Mesenchymal Stem Cells and colon cancer cells (HT29 and HCT-116) were cultured individually or in co-culture on 3-dimensional scaffolds. Conditioned media containing all secreted factors was harvested at day 1, 3 and 7. Chemokine secretion and expression were analyzed by Chemi-array, ELISA (Macrophage migration inhibitory factor (MIF), plasminogen activator inhibitor type 1 (PAI-1)) and RQ-PCR. Colon cancer cell migration and proliferation in response to recombinant PAI-1, MSCs and MSCs + antibody to PAI-1 was analyzed using Transwell inserts and an MTS proliferation assay respectively. Chemi-array revealed secretion of a wide range of factors by each cell population, including PAI-1and MIF. ELISA analysis revealed Mesenchymal Stem Cells to secrete the highest levels of PAI-1 (MSC mean 10.6 ng/mL, CCC mean 1.01 ng/mL), while colon cancer cells were the principal source of MIF. MSC-secreted PAI-1 stimulated significant migration of both CCC lines, with an antibody to the chemokine shown to block this effect (67–88% blocking,). A cell-line dependant effect on CCC proliferation was shown for Mesenchymal Stem Cell-secreted PAI-1 with HCT-116 cells showing decreased proliferation at all concentrations, and HT29 cells showing increased proliferation in the presence of higher PAI-1 levels. This is the first study to identify PAI-1 as an important mediator of Mesenchymal Stem Cell/colon cancer cell interactions and highlights the

Impact of Mesenchymal Stem Cell secreted PAI-1 on colon cancer cell migration and proliferation

International Nuclear Information System (INIS)

Hogan, Niamh M.; Joyce, Myles R.; Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy; Kerin, Michael J.; Dwyer, Roisin M.

2013-01-01

Highlights: •MSCs were directly co-cultured with colorectal cancer (CRC) cells on 3D scaffolds. •MSCs influence CRC protein/gene expression, proliferation and migration. •We report a significant functional role of MSC-secreted PAI-1 in colon cancer. -- Abstract: Mesenchymal Stem Cells are known to engraft and integrate into the architecture of colorectal tumours, with little known regarding their fate following engraftment. This study aimed to investigate mediators of Mesenchymal Stem Cell (MSC) and colon cancer cell (CCC) interactions. Mesenchymal Stem Cells and colon cancer cells (HT29 and HCT-116) were cultured individually or in co-culture on 3-dimensional scaffolds. Conditioned media containing all secreted factors was harvested at day 1, 3 and 7. Chemokine secretion and expression were analyzed by Chemi-array, ELISA (Macrophage migration inhibitory factor (MIF), plasminogen activator inhibitor type 1 (PAI-1)) and RQ-PCR. Colon cancer cell migration and proliferation in response to recombinant PAI-1, MSCs and MSCs + antibody to PAI-1 was analyzed using Transwell inserts and an MTS proliferation assay respectively. Chemi-array revealed secretion of a wide range of factors by each cell population, including PAI-1and MIF. ELISA analysis revealed Mesenchymal Stem Cells to secrete the highest levels of PAI-1 (MSC mean 10.6 ng/mL, CCC mean 1.01 ng/mL), while colon cancer cells were the principal source of MIF. MSC-secreted PAI-1 stimulated significant migration of both CCC lines, with an antibody to the chemokine shown to block this effect (67–88% blocking,). A cell-line dependant effect on CCC proliferation was shown for Mesenchymal Stem Cell-secreted PAI-1 with HCT-116 cells showing decreased proliferation at all concentrations, and HT29 cells showing increased proliferation in the presence of higher PAI-1 levels. This is the first study to identify PAI-1 as an important mediator of Mesenchymal Stem Cell/colon cancer cell interactions and highlights the

Antioxidant activity of inulin and its role in the prevention of human colonic muscle cell impairment induced by lipopolysaccharide mucosal exposure.

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Valentina Pasqualetti

Full Text Available BACKGROUND: Fructans, such as inulin, are dietary fibers which stimulate gastro-intestinal (GI function acting as prebiotics. Lipopolysaccharide (LPS impairs GI motility, through production of reactive oxygen species. The antioxidant activity of various fructans was tested and the protective effect of inulin on colonic smooth muscle cell (SMC impairment, induced by exposure of human mucosa to LPS, was assessed in an ex vivo experimental model. METHODS: The antioxidant capacity of fructans was measured in an in vitro system that simulates cooking and digestion processes. Human colonic mucosa and submucosa, obtained from disease-free margins of resected segments for cancer, were sealed between two chambers, with the mucosal side facing upwards with Krebs solution with or without purified LPS from a pathogenic strain of Escherichia coli (O111:B4 and inulin (Frutafit IQ, and the submucosal side facing downwards into Krebs solution. The solutions on the submucosal side were collected following mucosal exposure to Krebs in the absence (N-undernatant or presence of LPS (LPS-undernatant or LPS+inulin (LPS+INU-undernatant. Undernatants were tested for their antioxidant activity and the effects on SMCs contractility. Inulin protective effects on mucosa and submucosa layers were assessed measuring the protein oxidation level in the experimental conditions analyzed. RESULTS: Antioxidant activity of inulin, which was significantly higher compared to simple sugars, remained unaltered despite cooking and digestion processes. Inulin protected the mucosal and submucosal layers against protein oxidation. Following exposure to LPS-undernatant, a significant decrease in maximal acetylcholine (Ach-induced contraction was observed when compared to the contraction induced in cells incubated with the N-undernatant (4±1% vs 25±5% respectively, P<0.005 and this effect was completely prevented by pre-incubation of LPS with Inulin (35±5%. CONCLUSIONS: Inulin protects

Scaffold-Free Coculture Spheroids of Human Colonic Adenocarcinoma Cells and Normal Colonic Fibroblasts Promote Tumorigenicity in Nude Mice

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Jong-il Park

2016-02-01

Full Text Available The aim of this study was to form a scaffold-free coculture spheroid model of colonic adenocarcinoma cells (CACs and normal colonic fibroblasts (NCFs and to use the spheroids to investigate the role of NCFs in the tumorigenicity of CACs in nude mice. We analysed three-dimensional (3D scaffold-free coculture spheroids of CACs and NCFs. CAC Matrigel invasion assays and tumorigenicity assays in nude mice were performed to examine the effect of NCFs on CAC invasive behaviour and tumorigenicity in 3D spheroids. We investigated the expression pattern of fibroblast activation protein-α (FAP-α by immunohistochemical staining. CAC monocultures did not form densely-packed 3D spheroids, whereas cocultured CACs and NCFs formed 3D spheroids. The 3D coculture spheroids seeded on a Matrigel extracellular matrix showed higher CAC invasiveness compared to CACs alone or CACs and NCFs in suspension. 3D spheroids injected into nude mice generated more and faster-growing tumors compared to CACs alone or mixed suspensions consisting of CACs and NCFs. FAP-α was expressed in NCFs-CACs cocultures and xenograft tumors, whereas monocultures of NCFs or CACs were negative for FAP-α expression. Our findings provide evidence that the interaction between CACs and NCFs is essential for the tumorigenicity of cancer cells as well as for tumor propagation.

Nuclear microscopy of rat colon epithelial cells

International Nuclear Information System (INIS)

Ren, M.; Rajendran, Reshmi; Ng, Mary; Udalagama, Chammika; Rodrigues, Anna E.; Watt, Frank; Jenner, Andrew Michael

2011-01-01

Using Nuclear microscopy, we have investigated iron distributions in the colons of Sprague Dawley rats, in order to elucidate heme uptake. Four groups of five Sprague Dawley rats (mean weight 180 g) were fed different purified diets containing either heme diet (2.5% w/w hemoglobin), high fat diet (HFD) (18% w/w fat, 1% w/w cholesterol), 'western' diet (combination of hemoglobin 2.5% and 18% fat, 1% cholesterol) or control diet (7% w/w fat). After 4 weeks, animals were sacrificed by exsanguination after anaesthesia. Thin sections of frozen colon tissue were taken, freeze dried and scanned using nuclear microscopy utilising the techniques PIXE, RBS and STIM. The new data acquisition system (IonDaq) developed in CIBA was used to obtain high resolution images and line scans were used to map the iron distributions across the colon boundaries. The nuclear microscope results indicate that when HFD is given in addition to heme, the iron content of the epithelial cells that line the colon decreases, and the zinc in the smooth muscle wall increases. This implies that the level of heme and fat in diet has an important role in colon health, possibly by influencing epithelial cells directly or changing luminal composition such as bacterial flora or levels of metabolites and cytotoxins.

Nuclear microscopy of rat colon epithelial cells

Science.gov (United States)

Ren, M.; Rajendran, Reshmi; Ng, Mary; Udalagama, Chammika; Rodrigues, Anna E.; Watt, Frank; Jenner, Andrew Michael

2011-10-01

Using Nuclear microscopy, we have investigated iron distributions in the colons of Sprague Dawley rats, in order to elucidate heme uptake. Four groups of five Sprague Dawley rats (mean weight 180 g) were fed different purified diets containing either heme diet (2.5% w/w hemoglobin), high fat diet (HFD) (18% w/w fat, 1% w/w cholesterol), 'western' diet (combination of hemoglobin 2.5% and 18% fat, 1% cholesterol) or control diet (7% w/w fat). After 4 weeks, animals were sacrificed by exsanguination after anaesthesia. Thin sections of frozen colon tissue were taken, freeze dried and scanned using nuclear microscopy utilising the techniques PIXE, RBS and STIM. The new data acquisition system (IonDaq) developed in CIBA was used to obtain high resolution images and line scans were used to map the iron distributions across the colon boundaries. The nuclear microscope results indicate that when HFD is given in addition to heme, the iron content of the epithelial cells that line the colon decreases, and the zinc in the smooth muscle wall increases. This implies that the level of heme and fat in diet has an important role in colon health, possibly by influencing epithelial cells directly or changing luminal composition such as bacterial flora or levels of metabolites and cytotoxins.

Nuclear microscopy of rat colon epithelial cells

Energy Technology Data Exchange (ETDEWEB)

Ren, M., E-mail: phyrenmq@nus.edu.sg [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Rajendran, Reshmi [Lab of Molecular Imaging, Singapore Bioimaging Consotium, 11 Biopolis Way, 02-02 Helios, Singapore 138667 (Singapore); Ng, Mary [Department of Pharmacology, National University of Singapore (Singapore); Udalagama, Chammika; Rodrigues, Anna E.; Watt, Frank [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Jenner, Andrew Michael [Illawara Health and Medical Research Institute (IHMRI), University of Wollongong, NSW 2522 (Australia)

2011-10-15

Using Nuclear microscopy, we have investigated iron distributions in the colons of Sprague Dawley rats, in order to elucidate heme uptake. Four groups of five Sprague Dawley rats (mean weight 180 g) were fed different purified diets containing either heme diet (2.5% w/w hemoglobin), high fat diet (HFD) (18% w/w fat, 1% w/w cholesterol), 'western' diet (combination of hemoglobin 2.5% and 18% fat, 1% cholesterol) or control diet (7% w/w fat). After 4 weeks, animals were sacrificed by exsanguination after anaesthesia. Thin sections of frozen colon tissue were taken, freeze dried and scanned using nuclear microscopy utilising the techniques PIXE, RBS and STIM. The new data acquisition system (IonDaq) developed in CIBA was used to obtain high resolution images and line scans were used to map the iron distributions across the colon boundaries. The nuclear microscope results indicate that when HFD is given in addition to heme, the iron content of the epithelial cells that line the colon decreases, and the zinc in the smooth muscle wall increases. This implies that the level of heme and fat in diet has an important role in colon health, possibly by influencing epithelial cells directly or changing luminal composition such as bacterial flora or levels of metabolites and cytotoxins.

Epithelial and Mesenchymal Cells in the Bovine Colonic Mucosa Differ in Their Responsiveness to Escherichia coli Shiga Toxin 1

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Cells in the depth of the crypts in the bovine colon express CD77 molecules that potentially act as receptors for Shiga toxins (Stx). The implication of this finding for the intestinal colonization 25 of cattle with human pathogenic Stx-producing Escherichia coli (STEC) remains undefined. We used f...

Fermentation supernatants of Lactobacillus delbrueckii inhibit growth of human colon cancer cells and induce apoptosis through a caspase 3-dependent pathway.

Science.gov (United States)

Wan, Ying; Xin, Yi; Zhang, Cuili; Wu, Dachang; Ding, Dapeng; Tang, Li; Owusu, Lawrence; Bai, Jing; Li, Weiling

2014-05-01

Probiotic bacteria are known to exert a wide range of beneficial effects on their animal hosts. Therefore, the present study explored the effect of the supernatants obtained from Lactobacillus delbrueckii fermentation (LBF) on colon cancer. The results indicated that the proliferation of LBF solution-treated colon cancer SW620 cells was arrested and accumulated in the G1 phase in a concentration-dependent manner. The LBF solution efficiently induced apoptosis through the intrinsic caspase 3-depedent pathway, with a corresponding decreased expression of Bcl-2. The activity of matrix metalloproteinase 9, which is associated with the invasion of colon cancer cells, was also decreased in the LBF-treated cells. In conclusion, the results demonstrate the antitumor effect of LBF in vitro and may contribute to the development of novel therapies for the treatment of colon cancer.

Streptococcus sanguinis as an opportunistic bacteria in human oral cavity: Adherence, colonization, and invasion

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Hening Tjaturina Pramesti

2017-08-01

Full Text Available Streptococcus sanguinis (formerly S. sanguis is a Gram-positive, facultative anaerobe,  nonmotile , normal  inhabitant of the human oral cavity, and  a member of  the viridans group of streptococci. Among the streptococcus, S. sanguinis is a  primary colonizer in the human tooth surface or it is recognize as a ‘pioneer’ by forming dental plaque. The aim of this paper is to review the role of Streptococcus sanguinis  in the adherence to and  invasion of  human tissues.  S. sanguinis  has been reported  that it is associated  with healthy  tooth  surfaces  but not with caries. S. sanguinis  tend to involved in an interspecies interactions with Streptococcus mutans, which is known as  competition/coexistence within dental biofilm.  In their colonization, this bacteria used enzyme sortase A (SrtA to cleave  LPXTG-containing proteins sequence and  anchored  the  cell wall, while virulence factors  in infective endocarditis  involved housekeeping functions such as cell wall synthesis, amino acid and nucleic acid synthesis, and the ability to survive under anaerobic conditions.

Ultrastructural Histopathology of Vervet Monkey Colonic Epithelium After In Vitro Exposure to Cell-free Supernatants of Shigella Cultures

OpenAIRE

Hill, R. R.; Collins, N. E.; Cowley, H. M.

2011-01-01

The full dysentery syndrome of human shigellosis is often preceded by a transient diarrhoea that may be induced by bacterial extracellular products before invasion of the colonic mucosa and development of subsequent pathology. To examine this hypothesis, we studied the effects of cell-free cultures of Shigella sp. on the ultrastructure of monkey colonic epithelium in vitro. Clinical isolates of shigella strains were grown in a niche-simulating medium. Sheets of colon wall collected from verve...

Targeted inhibition of the phosphoinositide 3-kinase impairs cell proliferation, survival, and invasion in colon cancer

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Yang F

2017-09-01

Full Text Available Fei Yang,1,* Jun-Yi Gao,2,* Hua Chen,1 Zhen-Hua Du,1 Xue-Qun Zhang,3 Wei Gao4 1Department of Pathology, Jinan Central Hospital Affiliated to Shandong University, Jinan, 2Department of Clinical Medicine, Weifang Medical College, Weifang, 3Graduate School, Taishan Medical University, Xintai, 4Department of Oncology, Jinan Central Hospital Affiliated to Shandong University, Jinan, People’s Republic of China *These authors contributed equally to this work Background: Colon cancer is the third most common cancer in the world, and its metastasis and drug resistance are challenging for its effective treatment. The PI3K/Akt/mTOR pathway plays a crucial role in the pathogenesis of colon cancer. The aim of this study was to investigate the targeting of PI3K in colon cancer cells HT-29 and HCT-116 in vitro. Methods: In HT-29 and HCT-116 cells, BEZ235, a dual inhibitor of PI3K/mTOR, and shRNAtarget to PI3KCA were used to inhibit PI3K/Akt/mTOR pathway. The inhibition efficiency of PI3K/Akt/mTOR pathway was detected by RT-PCR and Western blot. Cell proliferation, migration, invasion, and apoptosis were evaluated by Cell Counting Kit-8, Transwell, and flow cytometry assays. The expression of apoptosis-related proteins (cleavage caspase 3, Bcl-2, Bax, and Bim were also detected. Results: We found that in HT-29 and HCT-116 cells, the treatment of BEZ235 (1 µM and PI3KCA knockdown inhibited the activation of PI3K/Akt/mTOR pathway and significantly suppressed cell proliferation, migration, and invasion of HT-29 and HCT-116 cells. In addition, we confirmed that knockdown of BEZ235 and PI3KCA induced cell apoptosis through the upregulated levels of cleavage caspase 3 and Bax and downregulated expression of Bcl-2 and Bim. Conclusion: Our results indicated that targeted inhibition of the PI3K/Akt/mTOR pathway impaired cell proliferation, survival, and invasion in human colon cancer. Keywords: human colon cancer, PI3K/Akt/mTOR pathway, BEZ235, PI3KCA knockdown

Effects of targeted delivery of propionate to the human colon on appetite regulation, body weight maintenance and adiposity in overweight adults

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Chambers, Edward S; Viardot, Alexander; Psichas, Arianna; Morrison, Douglas J; Murphy, Kevin G; Zac-Varghese, Sagen E K; MacDougall, Kenneth; Preston, Tom; Tedford, Catriona; Finlayson, Graham S; Blundell, John E; Bell, Jimmy D; Thomas, E Louise; Mt-Isa, Shahrul; Ashby, Deborah; Gibson, Glen R; Kolida, Sofia; Dhillo, Waljit S; Bloom, Stephen R; Morley, Wayne; Clegg, Stuart; Frost, Gary

2015-01-01

Objective The colonic microbiota ferment dietary fibres, producing short chain fatty acids. Recent evidence suggests that the short chain fatty acid propionate may play an important role in appetite regulation. We hypothesised that colonic delivery of propionate would increase peptide YY (PYY) and glucagon like peptide-1 (GLP-1) secretion in humans, and reduce energy intake and weight gain in overweight adults. Design To investigate whether propionate promotes PYY and GLP-1 secretion, a primary cultured human colonic cell model was developed. To deliver propionate specifically to the colon, we developed a novel inulin-propionate ester. An acute randomised, controlled cross-over study was used to assess the effects of this inulin-propionate ester on energy intake and plasma PYY and GLP-1 concentrations. The long-term effects of inulin-propionate ester on weight gain were subsequently assessed in a randomised, controlled 24-week study involving 60 overweight adults. Results Propionate significantly stimulated the release of PYY and GLP-1 from human colonic cells. Acute ingestion of 10 g inulin-propionate ester significantly increased postprandial plasma PYY and GLP-1 and reduced energy intake. Over 24 weeks, 10 g/day inulin-propionate ester supplementation significantly reduced weight gain, intra-abdominal adipose tissue distribution, intrahepatocellular lipid content and prevented the deterioration in insulin sensitivity observed in the inulin-control group. Conclusions These data demonstrate for the first time that increasing colonic propionate prevents weight gain in overweight adult humans. Trial registration number NCT00750438. PMID:25500202

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells

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Santarmaki, Valentina; Aindelis, Georgios; Tompoulidou, Evgenia; Lamprianidou, Eleftheria E.; Saxami, Georgia; Ypsilantis, Petros; Lampri, Evangeli S.; Simopoulos, Constantinos; Kotsianidis, Ioannis; Galanis, Alex; Kourkoutas, Yiannis; Dimitrellou, Dimitra; Chlichlia, Katerina

2016-01-01

Probiotic microorganisms such as lactic acid bacteria (LAB) exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof) on murine (CT26) and human (HT29) colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 109 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells). In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 109 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain. PMID:26849051

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells.

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Angeliki Tiptiri-Kourpeti

Full Text Available Probiotic microorganisms such as lactic acid bacteria (LAB exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof on murine (CT26 and human (HT29 colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 10(9 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells. In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 10(9 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain.

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells.

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Tiptiri-Kourpeti, Angeliki; Spyridopoulou, Katerina; Santarmaki, Valentina; Aindelis, Georgios; Tompoulidou, Evgenia; Lamprianidou, Eleftheria E; Saxami, Georgia; Ypsilantis, Petros; Lampri, Evangeli S; Simopoulos, Constantinos; Kotsianidis, Ioannis; Galanis, Alex; Kourkoutas, Yiannis; Dimitrellou, Dimitra; Chlichlia, Katerina

2016-01-01

Probiotic microorganisms such as lactic acid bacteria (LAB) exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof) on murine (CT26) and human (HT29) colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 10(9) CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells). In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 10(9) CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain.

Ursodeoxycholic acid inhibits the proliferation of colon cancer cells by regulating oxidative stress and cancer stem-like cell growth

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Kim, EuiJoo

2017-01-01

Introduction The regulation of reactive oxygen species (ROS) exists as a therapeutic target for cancer treatments. Previous studies have shown that ursodeoxycholic acid (UDCA) suppresses the proliferation of colon cancer cells. The aim of this study was to evaluate the effect of UDCA upon the proliferation of colon cancer cells as a direct result of the regulation of ROS. Method Colon cancer cell lines (HT29 and HCT116) were treated with UDCA. The total number of cells and the number of dead cells were determined using cell counters. A fluorescein isothiocyanate-bromodeoxyuridine flow kit was used to analyze cell cycle variations. Upon exposure to UDCA, the protein levels of p27, p21, CDK2, CDK4 and CDK6 were determined using western blotting, and qRT-PCR was used to determine levels of mRNA. We preformed dichlorofluorescindiacetate (DCF-DA) staining to detect alteration of intracellular ROS using fluorescence activated cell sorting (FACS). Colon cancer stem-like cell lines were generated by tumorsphere culture and treated with UDCA for seven days. The total number of tumorspheres was determined using microscopy. Results We found that UDCA reduced the total number of colon cancer cells, but did not increase the number of dead cells. UDCA inhibited the G1/S and G2/M transition phases in colon cancer cells. UDCA induced expression of cell cycle inhibitors such as p27 and p21. However, it was determined that UDCA suppressed levels of CDK2, CDK4, and CDK6. UDCA regulated intracellular ROS generation in colon cancer cells, and induced activation of Erk1/2. Finally, UDCA inhibited formation of colon cancer stem-like cells. Conclusion Our results indicate that UDCA suppresses proliferation through regulation of oxidative stress in colon cancer cells, as well as colon cancer stem-like cells. PMID:28708871

Antioxidant potential of buffalo and cow milk Cheddar cheeses to tackle human colon adenocarcinoma (Caco-2 cells

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Nuzhat Huma

2018-02-01

Full Text Available Objective The aim of present study was to assess the anti-oxidant potential of water-soluble peptides (WSPs extract derived from buffalo and cow milk Cheddar cheeses at different stages of ripening. Methods The antioxidant potential of WSPs extract was assessed through 2,2’-azinobis-3-ethylbenzothiazoline-6sulfonic acid (ABTS-radical scavenging activity. In addition, impact of WSPs extract on cell viability and production of reactive oxygen species (ROS in human colon adenocarcinoma Caco-2 (tert-butylhydroperoxide-induced cell lines was also evaluated. Results The ABTS-radical scavenging activity increased progressively with ripening period and dose-dependently in both cheeses. However, peptide extract from buffalo milk Cheddar cheese demonstrated relatively higher activity due to higher contents of water-soluble nitrogen. Intracellular ROS production in Caco-2 cells decreased significantly (p<0.05 till 150th day of cheese ripening and remained constant thereafter. Additionally, dose-dependent response of WSPs extract on antioxidant activity was noticed in the Caco-2 cell line. Conclusion On the basis of current in vitro study, the Cheddar cheese WSPs extract can protect intestinal epithelium against oxidative stress due to their antioxidant activity.

Gamma (γ) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (γ) expression in SW 480 human colon cancer cell lines

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Campbell, Sharon E; Stone, William L; Whaley, Sarah G; Qui, Min; Krishnan, Koyamangalath

2003-01-01

Background Tocopherols are lipid soluble antioxidants that exist as eight structurally different isoforms. The intake of γ-tocopherol is higher than α-tocopherol in the average US diet. The clinical results of the effects of vitamin E as a cancer preventive agent have been inconsistent. All published clinical trials with vitamin E have used α-tocopherol. Recent epidemiological, experimental and molecular studies suggest that γ-tocopherol may be a more potent chemopreventive form of vitamin E compared to the more-studied α-tocopherol. γ-Tocopherol exhibits differences in its ability to detoxify nitrogen dioxide, growth inhibitory effects on selected cancer cell lines, inhibition of neoplastic transformation in embryonic fibroblasts, and inhibition of cyclooxygenase-2 (COX-2) activity in macrophages and epithelial cells. Peroxisome proliferator activator receptor γ (PPARγ) is a promising molecular target for colon cancer prevention. Upregulation of PPARγ activity is anticarcinogenic through its effects on downstream genes that affect cellular proliferation and apoptosis. The thiazolidine class of drugs are powerful PPARγ ligands. Vitamin E has structural similarity to the thiazolidine, troglitazone. In this investigation, we tested the effects of both α and γ tocopherol on the expression of PPARγ mRNA and protein in SW 480 colon cancer cell lines. We also measured the intracellular concentrations of vitamin E in SW 480 colon cancer cell lines. Results We have discovered that the α and γ isoforms of vitamin E upregulate PPARγ mRNA and protein expression in the SW480 colon cancer cell lines. γ-Tocopherol is a better modulator of PPARγ expression than α-tocopherol at the concentrations tested. Intracellular concentrations increased as the vitamin E concentration added to the media was increased. Further, γ-tocopherol-treated cells have higher intracellular tocopherol concentrations than those treated with the same concentrations of �

Gamma (γ) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (γ) expression in SW 480 human colon cancer cell lines

International Nuclear Information System (INIS)

Campbell, Sharon E; Stone, William L; Whaley, Sarah G; Qui, Min; Krishnan, Koyamangalath

2003-01-01

Tocopherols are lipid soluble antioxidants that exist as eight structurally different isoforms. The intake of γ-tocopherol is higher than α-tocopherol in the average US diet. The clinical results of the effects of vitamin E as a cancer preventive agent have been inconsistent. All published clinical trials with vitamin E have used α-tocopherol. Recent epidemiological, experimental and molecular studies suggest that γ-tocopherol may be a more potent chemopreventive form of vitamin E compared to the more-studied α-tocopherol. γ-Tocopherol exhibits differences in its ability to detoxify nitrogen dioxide, growth inhibitory effects on selected cancer cell lines, inhibition of neoplastic transformation in embryonic fibroblasts, and inhibition of cyclooxygenase-2 (COX-2) activity in macrophages and epithelial cells. Peroxisome proliferator activator receptor γ (PPARγ) is a promising molecular target for colon cancer prevention. Upregulation of PPARγ activity is anticarcinogenic through its effects on downstream genes that affect cellular proliferation and apoptosis. The thiazolidine class of drugs are powerful PPARγ ligands. Vitamin E has structural similarity to the thiazolidine, troglitazone. In this investigation, we tested the effects of both α and γ tocopherol on the expression of PPARγ mRNA and protein in SW 480 colon cancer cell lines. We also measured the intracellular concentrations of vitamin E in SW 480 colon cancer cell lines. We have discovered that the α and γ isoforms of vitamin E upregulate PPARγ mRNA and protein expression in the SW480 colon cancer cell lines. γ-Tocopherol is a better modulator of PPARγ expression than α-tocopherol at the concentrations tested. Intracellular concentrations increased as the vitamin E concentration added to the media was increased. Further, γ-tocopherol-treated cells have higher intracellular tocopherol concentrations than those treated with the same concentrations of α-tocopherol. Our data suggest that

Identifying colon cancer risk modules with better classification performance based on human signaling network.

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Qu, Xiaoli; Xie, Ruiqiang; Chen, Lina; Feng, Chenchen; Zhou, Yanyan; Li, Wan; Huang, Hao; Jia, Xu; Lv, Junjie; He, Yuehan; Du, Youwen; Li, Weiguo; Shi, Yuchen; He, Weiming

2014-10-01

Identifying differences between normal and tumor samples from a modular perspective may help to improve our understanding of the mechanisms responsible for colon cancer. Many cancer studies have shown that signaling transduction and biological pathways are disturbed in disease states, and expression profiles can distinguish variations in diseases. In this study, we integrated a weighted human signaling network and gene expression profiles to select risk modules associated with tumor conditions. Risk modules as classification features by our method had a better classification performance than other methods, and one risk module for colon cancer had a good classification performance for distinguishing between normal/tumor samples and between tumor stages. All genes in the module were annotated to the biological process of positive regulation of cell proliferation, and were highly associated with colon cancer. These results suggested that these genes might be the potential risk genes for colon cancer. Copyright © 2013. Published by Elsevier Inc.

Uptake and cytotoxicity of poly(D,L-lactide-co-glycolide) nanoparticles in human colon adenocarcinoma cells

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Katsikari, A. [Laboratory of General Microbiology, Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Sciences and Mathematics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Patronidou, Chr.; Kiparissides, C. [Section of Analysis, Design and Control of Chemical Processes and Plants, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Arsenakis, M., E-mail: arsenaki@bio.auth.g [Laboratory of General Microbiology, Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Sciences and Mathematics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)

2009-12-15

The main objectives of the present study were to evaluate the cytotoxicity and the mechanisms of uptake of biodegradable lactic acid-glycolic acid copolymer (PLGA) nanoparticle carrier systems in vitro using the human colon adenocarcinoma cell line Caco2. Nanoparticles (NPs) (PLGA 75:25) with an average diameter of 299.5 nm containing bovine serum albumin labeled with fluorescein isothiocyanate (BSA-FITC) as a fluorescent model protein marker were formulated by the double emulsion technique. Various parameters influencing the internalization process by Caco2 cells including concentration of NPs, duration of contact time and cell culture conditions were studied. After overnight exposure of NPs to cells at 37 deg. C, the cell uptake capacity varied in accord with NP concentration, over the 25-800 mug/ml concentration range tested. Maximal uptake of nanoparticles at 37 deg. C occurred at 4 h and was inhibited significantly at 4 deg. C. The extent of NPs internalization was evaluated by confocal laser scanning microscopy. Potential NP toxicity evaluated by modified MTS and lactate dehydrogenase (LDH) colorimetric cytotoxicity tests, measuring mitochondrial activity and membrane integrity respectively, showed that cell viability is significantly reduced at PLGA nanoparticle concentrations greater than 700 mug/ml after 24 and 48 h respectively. The results obtained in vitro for BSA-FITC loaded PLGA nanoparticles underline their potential as carriers for peptide delivery and their utility for the study of NP cell transport and trafficking mechanisms.

Influence of ethacrynic acid on glutathione S-transferase pi transcript and protein half-lives in human colon cancer cells.

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Shen, H; Ranganathan, S; Kuzmich, S; Tew, K D

1995-10-12

Ethacrynic acid (EA) is a plant phenolic acid that is both an inhibitor and an inducer of glutathione S-transferase (GST) activity. To determine contributory factors in the increased GST activity caused by EA treatment, human colon carcinoma HT29 cells were compared with a cloned EA-resistant population (HT6-8) maintained in medium containing 72 microM EA. Several factors are involved in the increased expression of GST pi in HT6-8. For example, nuclear run-on experiments showed an approximately 2-fold increase in the rate of transcription of GST pi. In addition, the half-life of GST pi transcript was increased from 4.1 (wild type, HT29, HT4-1) to 8.4 hr. The half-life of GST pi protein was 1-2 hr in HT4-1 cells versus 8-9 hr in HT6-8 cells. When either human ovarian carcinoma cells (SKOV3) or human prostatic carcinoma cells (DU145) were treated with EA, the half-life of the GST pi transcript was also increased. The transcript half-lives of another thiol-metabolism enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), and a phase II detoxification enzyme, dihydrodiol dehydrogenase (DDH), were also increased in HT6-8, SKOV3 and DU145 cells treated with EA. However, the half-lives of transcripts from "housekeeping genes," such as glyceraldehyde 3-phosphate dehydrogenase (G3PDH), beta-actin and beta-tubulin, were not changed in these cell lines following EA. Apparently, a number of coordinated factors are involved in EA-enhanced expression of GST pi and other detoxification enzymes.

Colonic Fermentation: A Neglected Topic in Human Physiology Education

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Valeur, Jorgen; Berstad, Arnold

2010-01-01

Human physiology textbooks tend to limit their discussion of colonic functions to those of absorbing water and electrolytes and storing waste material. However, the colon is a highly active metabolic organ, containing an exceedingly complex society of microbes. By means of fermentation, gastrointestinal microbes break down nutrients that cannot be…

Effects of the differentiating agents sodium butyrate and N-methylformamide on the oxygen enhancement ratio of human colon tumor cells

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Hallows, K.R.; Bliven, S.F.; Leith, J.T.

1988-01-01

We have previously shown that chronic adaptation of human tumor cells to the differentiation-inducing agents N-methylformamide (NMF) and sodium butyrate (NAB) increases the sensitivity of oxic cells to graded single doses of X rays. These studies were carried out to define the sensitivity of hypoxic cells after adaptation. Clone A colon tumor cells were grown for three passages in medium containing 170 mM NMF or 2 mM NAB and irradiated in suspension culture, after gassing with either oxygen (60 min) or ultrapure nitrogen (90 min), and complete survival curves were generated. Using the linear-quadratic equation to describe the data, it was found that NMF and NAB produced increased X-ray killing of hypoxic cells. At the 10% level of survival, the dose-modifying factors were about 1.20 and 1.25 for NMF- and NAB-adapted hypoxic cells, respectively, as compared to hypoxic control cells. However, since both oxic and hypoxic cells exhibited increased sensitivity after NMF and NAB adaptation, there was no major change in the oxygen enhancement ratio

ER-Stress-Induced Differentiation Sensitizes Colon Cancer Stem Cells to Chemotherapy

NARCIS (Netherlands)

Wielenga, Mattheus C. B.; Colak, Selcuk; Heijmans, Jarom; van Lidth de Jeude, Jooske F.; Rodermond, Hans M.; Paton, James C.; Paton, Adrienne W.; Vermeulen, Louis; Medema, Jan Paul; van den Brink, Gijs R.

2015-01-01

Colon cancer stem cells (colon-CSCs) are more resistant to conventional chemotherapy than differentiated cancer cells. This subset of therapy refractory cells is therefore believed to play an important role in post-therapeutic tumor relapse. In order to improve the rate of sustained response to

Nicotine promotes cell proliferation via α7-nicotinic acetylcholine receptor and catecholamine-synthesizing enzymes-mediated pathway in human colon adenocarcinoma HT-29 cells

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Wong, Helen Pui Shan; Yu Le; Lam, Emily Kai Yee; Tai, Emily Kin Ki; Wu, William Ka Kei; Cho, Chi Hin

2007-01-01

Cigarette smoking has been implicated in colon cancer. Nicotine is a major alkaloid in cigarette smoke. In the present study, we showed that nicotine stimulated HT-29 cell proliferation and adrenaline production in a dose-dependent manner. The stimulatory action of nicotine was reversed by atenolol and ICI 118,551, a β 1 - and β 2 -selective antagonist, respectively, suggesting the role of β-adrenoceptors in mediating the action. Nicotine also significantly upregulated the expression of the catecholamine-synthesizing enzymes [tyrosine hydroxylase (TH), dopamine-β-hydroxylase (DβH) and phenylethanolamine N-methyltransferase]. Inhibitor of TH, a rate-limiting enzyme in the catecholamine-biosynthesis pathway, reduced the actions of nicotine on cell proliferation and adrenaline production. Expression of α7-nicotinic acetylcholine receptor (α7-nAChR) was demonstrated in HT-29 cells. Methyllycaconitine, an α7-nAChR antagonist, reversed the stimulatory actions of nicotine on cell proliferation, TH and DβH expression as well as adrenaline production. Taken together, through the action on α7-nAChR nicotine stimulates HT-29 cell proliferation via the upregulation of the catecholamine-synthesis pathway and ultimately adrenaline production and β-adrenergic activation. These data reveal the contributory role α7-nAChR and β-adrenoceptors in the tumorigenesis of colon cancer cells and partly elucidate the carcinogenic action of cigarette smoke on colon cancer

Colonic inflammation in mice is improved by cigarette smoke through iNKT cells recruitment.

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Muriel Montbarbon

Full Text Available Cigarette smoke (CS protects against intestinal inflammation during ulcerative colitis. Immunoregulatory mechanisms sustaining this effect remain unknown. The aim of this study was to assess the effects of CS on experimental colitis and to characterize the intestinal inflammatory response at the cellular and molecular levels. Using the InExpose® System, a smoking device accurately reproducing human smoking habit, we pre-exposed C57BL/6 mice for 2 weeks to CS, and then we induced colitis by administration of dextran sodium sulfate (DSS. This system allowed us to demonstrate that CS exposure improved colonic inflammation (significant decrease in clinical score, body weight loss and weight/length colonic ratio. This improvement was associated with a significant decrease in colonic proinflammatory Th1/Th17 cytokine expression, as compared to unexposed mice (TNF (p=0.0169, IFNγ (p<0.0001, and IL-17 (p=0.0008. Smoke exposure also induced an increased expression of IL-10 mRNA (p=0.0035 and a marked recruitment of iNKT (invariant Natural Killer T; CD45+ TCRβ+ CD1d tetramer+ cells in the colon of DSS-untreated mice. Demonstration of the role of iNKT cells in CS-dependent colitis improvement was performed using two different strains of NKT cells deficient mice. Indeed, in Jα18KO and CD1dKO animals, CS exposure failed to induce significant regulation of DSS-induced colitis both at the clinical and molecular levels. Thus, our study demonstrates that iNKT cells are pivotal actors in the CS-dependent protection of the colon. These results highlight the role of intestinal iNKT lymphocytes and their responsiveness to environmental stimuli. Targeting iNKT cells would represent a new therapeutic way for inflammatory bowel diseases.

Frondoside A Enhances the Anti-Cancer Effects of Oxaliplatin and 5-Fluorouracil on Colon Cancer Cells

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Samir Attoub

2018-05-01

Full Text Available Over recent years, we have demonstrated that Frondoside A, a triterpenoid glycoside isolated from an Atlantic sea cucumber, has potent in vitro and in vivo anti-cancer effects against human pancreatic, breast, and lung cancer. We have also demonstrated that Frondoside A is able to potentiate and/or synergize the anti-cancer effects of major classical cytotoxic agents, namely, gemcitabine, paclitaxel, and cisplatin, in the treatment of pancreatic, breast, and lung cancer, respectively. This study evaluates the impact of Frondoside A alone and in combination with the standard cytotoxic drugs oxaliplatin and 5-fluorouracil (5-FU in the treatment of colon cancer using three human colon cancer cell lines, namely, HT-29, HCT-116, and HCT8/S11. We demonstrate that Frondoside A, oxaliplatin, and 5-FU cause a concentration- and time-dependent reduction in the number of HT-29 colon cancer cells. A concentration of 2.5 µM of Frondoside A led to almost 100% inhibition of cell numbers at 72 h. A similar effect was only observed with a much higher concentration (100 µM of oxaliplatin or 5-FU. The reduction in cell numbers by Frondoside A, oxaliplatin, and 5-FU was also confirmed in two other colon cancer cell lines, namely, HCT8/S11 and HCT-116, treated for 48 h. The combinations of low concentrations of these drugs for 48 h in vitro clearly demonstrated that Frondoside A enhances the inhibition of cell numbers induced by oxaliplatin or 5-FU. Similarly, such a combination also efficiently inhibited colony growth in vitro. Interestingly, we found that the inhibition of ERK1/2 phosphorylation was significantly enhanced when Frondoside A was used in combination treatments. Moreover, we show that Frondoside A and 5-FU, when used alone, induce a concentration-dependent induction of apoptosis and that their pro-apoptotic effect is dramatically enhanced when used in combination. We further demonstrate that apoptosis induction upon the treatment of colon cancer

Expression of ICAM-1 in colon epithelial cells

DEFF Research Database (Denmark)

Vainer, Ben; Sørensen, Susanne; Seidelin, Jakob

2003-01-01

Studies have suggested that in ulcerative colitis (UC), intercellular adhesion molecule-1 (ICAM-1) is involved in migration of leukocytes toward the colonic epithelium. A suitable in vitro model of chronic colonic inflammation does not exist, and the role of the epithelium is based on monolayers ...... of cancer cells. Conflicting results exist on epithelial ICAM-1 expression, and the aim of this study was to compare the expression in various models of colonic epithelium.......Studies have suggested that in ulcerative colitis (UC), intercellular adhesion molecule-1 (ICAM-1) is involved in migration of leukocytes toward the colonic epithelium. A suitable in vitro model of chronic colonic inflammation does not exist, and the role of the epithelium is based on monolayers...

Neurotensin receptor 1 gene activation by the Tcf/beta-catenin pathway is an early event in human colonic adenomas.

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Souazé, Frédérique; Viardot-Foucault, Véronique; Roullet, Nicolas; Toy-Miou-Leong, Mireille; Gompel, Anne; Bruyneel, Erik; Comperat, Eva; Faux, Maree C; Mareel, Marc; Rostène, William; Fléjou, Jean-François; Gespach, Christian; Forgez, Patricia

2006-04-01

Alterations in the Wnt/APC (adenomatous polyposis coli) signalling pathway, resulting in beta-catenin/T cell factor (Tcf)-dependent transcriptional gene activation, are frequently detected in familial and sporadic colon cancers. The neuropeptide neurotensin (NT) is widely distributed in the gastrointestinal tract. Its proliferative and survival effects are mediated by a G-protein coupled receptor, the NT1 receptor. NT1 receptor is not expressed in normal colon epithelial cells, but is over expressed in a number of cancer cells and tissues suggesting a link to the outgrowth of human colon cancer. Our results demonstrate that the upregulation of NT1 receptor occurring in colon cancer is the result of Wnt/APC signalling pathway activation. We first established the functionality of the Tcf response element within the NT1 receptor promoter. Consequently, we observed the activation of NT1 receptor gene by agents causing beta-catenin cytosolic accumulation, as well as a strong decline of endogenous receptor when wt-APC was restored. At the cellular level, the re-establishment of wt-APC phenotype resulted in the impaired functionality of NT1 receptor, like the breakdown in NT-induced intracellular calcium mobilization and the loss of NT pro-invasive effect. We corroborated the Wnt/APC signalling pathway on the NT1 receptor promoter activation with human colon carcinogenesis, and showed that NT1 receptor gene activation was perfectly correlated with nuclear or cytoplasmic beta-catenin localization while NT1 receptor was absent when beta-catenin was localized at the cell-cell junction in early adenomas of patients with familial adenomatous polyposis, hereditary non-polyposis colorectal cancer and loss of heterozygosity tumours. In this report we establish a novel link in vitro between the Tcf/beta-catenin pathway and NT1 receptor promoter activation.

Differential expression of nanog1 and nanogp8 in colon cancer cells

International Nuclear Information System (INIS)

Ishiguro, Tatsuya; Sato, Ai; Ohata, Hirokazu; Sakai, Hiroaki; Nakagama, Hitoshi; Okamoto, Koji

2012-01-01

Highlights: ► Nanog is expressed in a majority of colon cancer cell lines examined. ► Both nanog1 and nanogp8 are expressed in colon cancer cells with varying ratios. ► Nanog mediates cell proliferation of colon cancer cells. ► Nanog predominantly localizes in cytoplasm of colon cancer cells. -- Abstract: Nanog, a homeodomain transcription factor, is an essential regulator for promotion of self-renewal of embryonic stem cells and inhibition of their differentiation. It has been demonstrated that nanog1 as well as nanogp8, a retrogene of nanog1, is preferentially expressed in advanced stages of several types of cancer, suggesting their involvement during cancer progression. Here, we investigated the expression of Nanog in well-characterized colon cancer cell lines. Expression of Nanog was detectable in 5 (HCT116, HT29, RKO, SW48, SW620) out of seven cell lines examined. RNA expression analyses of nanog1 and nanogp8 indicated that, while nanog1 was a major form in SW620 as well as in teratoma cells Tera-2, nanogp8 was preferentially expressed in HT29 and HCT116. In accordance with this, shRNA-mediated knockdown of nanog1 caused the reduction of Nanog in SW620 but not in HT29. Inhibition of Nanog in SW620 cells negatively affected cell proliferation and tumor formation in mouse xenograft. Biochemical subcellular fractionation and immunostaining analyses revealed predominant localization of Nanog in cytoplasm in SW620 and HT29, while it was mainly localized in nucleus in Tera-2. Our data indicate that nanog1 and nanogp8 are differentially expressed in colon cancer cells, and suggest that their expression contributes to proliferation of colon cancer cells.

Differential expression of nanog1 and nanogp8 in colon cancer cells

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Ishiguro, Tatsuya; Sato, Ai; Ohata, Hirokazu; Sakai, Hiroaki [Division of Cancer Differentiation, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Nakagama, Hitoshi, E-mail: hnakagam@ncc.go.jp [Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Okamoto, Koji, E-mail: kojokamo@ncc.go.jo [Division of Cancer Differentiation, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)

2012-02-10

Highlights: Black-Right-Pointing-Pointer Nanog is expressed in a majority of colon cancer cell lines examined. Black-Right-Pointing-Pointer Both nanog1 and nanogp8 are expressed in colon cancer cells with varying ratios. Black-Right-Pointing-Pointer Nanog mediates cell proliferation of colon cancer cells. Black-Right-Pointing-Pointer Nanog predominantly localizes in cytoplasm of colon cancer cells. -- Abstract: Nanog, a homeodomain transcription factor, is an essential regulator for promotion of self-renewal of embryonic stem cells and inhibition of their differentiation. It has been demonstrated that nanog1 as well as nanogp8, a retrogene of nanog1, is preferentially expressed in advanced stages of several types of cancer, suggesting their involvement during cancer progression. Here, we investigated the expression of Nanog in well-characterized colon cancer cell lines. Expression of Nanog was detectable in 5 (HCT116, HT29, RKO, SW48, SW620) out of seven cell lines examined. RNA expression analyses of nanog1 and nanogp8 indicated that, while nanog1 was a major form in SW620 as well as in teratoma cells Tera-2, nanogp8 was preferentially expressed in HT29 and HCT116. In accordance with this, shRNA-mediated knockdown of nanog1 caused the reduction of Nanog in SW620 but not in HT29. Inhibition of Nanog in SW620 cells negatively affected cell proliferation and tumor formation in mouse xenograft. Biochemical subcellular fractionation and immunostaining analyses revealed predominant localization of Nanog in cytoplasm in SW620 and HT29, while it was mainly localized in nucleus in Tera-2. Our data indicate that nanog1 and nanogp8 are differentially expressed in colon cancer cells, and suggest that their expression contributes to proliferation of colon cancer cells.

Evidence for Two Modes of Synergistic Induction of Apoptosis by Mapatumumab and Oxaliplatin in Combination with Hyperthermia in Human Colon Cancer Cells

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Song, Xinxin; Kim, Seog-Young; Lee, Yong J.

2013-01-01

Colorectal cancer is the third leading cause of cancer-related mortality in the world-- the main cause of death from colorectal cancer is hepatic metastases, which can be treated with isolated hepatic perfusion (IHP). Searching for the most clinically relevant approaches for treating colorectal metastatic disease by isolated hepatic perfusion (IHP), we developed the application of oxaliplatin concomitantly with hyperthermia and humanized death receptor 4 (DR4) antibody mapatumumab (Mapa), and investigated the molecular mechanisms of this multimodality treatment in human colon cancer cell lines CX-1 and HCT116 as well as human colon cancer stem cells Tu-12, Tu-21 and Tu-22. We showed here, in this study, that the synergistic effect of the multimodality treatment-induced apoptosis was caspase dependent and activated death signaling via both the extrinsic apoptotic pathway and the intrinsic pathway. Death signaling was activated by c-Jun N-terminal kinase (JNK) signaling which led to Bcl-xL phosphorylation at serine 62, decreasing the anti-apoptotic activity of Bcl-xL, which contributed to the intrinsic pathway. The downregulation of cellular FLICE inhibitory protein long isoform (c-FLIPL) in the extrinsic pathway was accomplished through ubiquitination at lysine residue (K) 195 and protein synthesis inhibition. Overexpression of c-FLIPL mutant (K195R) and Bcl-xL mutant (S62A) completely abrogated the synergistic effect. The successful outcome of this study supports the application of multimodality strategy to patients with colorectal hepatic metastases who fail to respond to standard chemoradiotherapy that predominantly targets the mitochondrial apoptotic pathway. PMID:24013390

Methylselenol, a selenium metabolite, plays common and different roles in cancerous colon HCT116 cell and noncancerous NCM460 colon cell proliferation.

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Zeng, Huawei; Briske-Anderson, Mary; Wu, Min; Moyer, Mary P

2012-01-01

Methylselenol is hypothesized to be a critical selenium metabolite for anticancer action, and differential chemopreventive effects of methylselenol on cancerous and noncancerous cells may play an important role. In this study, the submicromolar concentrations of methylselenol were generated by incubating methionase with seleno-L methionine, and colon-cancer-derived HCT-116 cells and noncancerous colon NCM460 cells were exposed to methylselenol. Methylselenol exposure inhibited cell growth and led to an increase in G1 and G2 fractions with a concomitant drop in S-phase and an induction of apoptosis in HCT116, but to a much lesser extent in NCM460 colon cells. Similarly, the examination of mitogen-activated protein kinase (MAPK) and cellular myelocytomatosis oncogene (c-Myc) signaling status revealed that methylselenol inhibited the phosphorylation of extracellular-regulated kinase1/2 and p38 mitogen-activated protein kinase and the expression of c-Myc in HCT116 cells, but also to a lesser extent in NCM460 cells. The other finding is that methylselenol inhibits sarcoma kinase phosphorylation in HCT116 cells. In contrast, methylselenol upregulated the phosphorylation of sarcoma and focal adhesion kinase survival signals in the noncancerous NCM460 cells. Collectively, methylselenol's stronger potential of inhibiting cell proliferation/survival signals in the cancerous HCT116 cells when compared with that in noncancerous NCM460 cells may partly explain the potential of methylselenol's anticancer action.

Evaluation of an in vitro faecal degradation method for early assessment of the impact of colonic degradation on colonic absorption in humans.

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Tannergren, Christer; Borde, Anders; Boreström, Cecilia; Abrahamsson, Bertil; Lindahl, Anders

2014-06-16

The objective of this study was to develop and evaluate an in vitro method to investigate bacterial-mediated luminal degradation of drugs in colon in humans. This would be a valuable tool for the assessment of drug candidates during early drug development, especially for compounds intended to be developed as oral extended release formulations. Freshly prepared faecal homogenate from healthy human volunteers (n=3-18), dog (n=6) and rat (colon and caecal content, n=3) was homogenised with 3.8 parts (w/w) physiological saline under anaerobical conditions. Four model compounds (almokalant, budesonide, ximelagatran and metoprolol) were then incubated (n=3-18) separately in the human faecal homogenate for up to 120min at 37°C. In addition, ximelagatran was also incubated in the faecal or colonic content from dog and rat. The mean (±SD) in vitro half-life for almokalant, budesonide and ximelagatran was 39±1, 68±21 and 26±12min, respectively, in the human faecal homogenate. Metoprolol was found to be stable in the in vitro model. The in vitro degradation data was then compared to literature data on fraction absorbed after direct colon administration in humans. The percentage of drug remaining after 60min of in vitro incubation correlated (R(2)=0.90) with the fraction absorbed from colon in humans. The mean in vitro half-life of ximelagatran was similar in human faeces (26±12min) and rat colon content (34±31min), but significantly (pdegradation in vivo was rapidly degraded in the faecal homogenates as well as quantitatively since a correlation was established between percentage degraded in vitro at 60min and fraction absorbed in the colon for the model drugs, which have no other absorption limiting properties. Also, the method is easy to use from a technical point of view, which suggests that the method is suitable for use in early assessment of colonic absorption of extended release formulation candidates. Further improvement of the confidence in the use of the

Prostaglandin E2 stimulates Fas ligand expression via the EP1 receptor in colon cancer cells.

LENUS (Irish Health Repository)

O'Callaghan, G

2012-02-03

Fas ligand (FasL\\/CD95L) is a member of the tumour necrosis factor superfamily that triggers apoptosis following crosslinking of the Fas receptor. Despite studies strongly implicating tumour-expressed FasL as a major inhibitor of the anti-tumour immune response, little is known about the mechanisms that regulate FasL expression in tumours. In this study, we show that the cyclooxygenase (COX) signalling pathway, and in particular prostaglandin E(2) (PGE(2)), plays a role in the upregulation of FasL expression in colon cancer. Suppression of either COX-2 or COX-1 by RNA interference in HCA-7 and HT29 colon tumour cells reduced FasL expression at both the mRNA and protein level. Conversely, stimulation with PGE(2) increased FasL expression and these cells showed increased cytotoxicity against Fas-sensitive Jurkat T cells. Prostaglandin E(2)-induced FasL expression was mediated by signalling via the EP1 receptor. Moreover, immunohistochemical analysis using serial sections of human colon adenocarcinomas revealed a strong positive correlation between COX-2 and FasL (r=0.722; P<0.0001) expression, and between EP1 receptor and FasL (r=0.740; P<0.0001) expression, in the tumour cells. Thus, these findings indicate that PGE(2) positively regulates FasL expression in colon tumour cells, adding another pro-neoplastic activity to PGE(2).

NADPH oxidase 1 supports proliferation of colon cancer cells by modulating reactive oxygen species-dependent signal transduction.

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Juhasz, Agnes; Markel, Susan; Gaur, Shikha; Liu, Han; Lu, Jiamo; Jiang, Guojian; Wu, Xiwei; Antony, Smitha; Wu, Yongzhong; Melillo, Giovanni; Meitzler, Jennifer L; Haines, Diana C; Butcher, Donna; Roy, Krishnendu; Doroshow, James H

2017-05-12

Reactive oxygen species (ROS) play a critical role in cell signaling and proliferation. NADPH oxidase 1 (NOX1), a membrane-bound flavin dehydrogenase that generates O 2 ̇̄ , is highly expressed in colon cancer. To investigate the role that NOX1 plays in colon cancer growth, we used shRNA to decrease NOX1 expression stably in HT-29 human colon cancer cells. The 80-90% decrease in NOX1 expression achieved by RNAi produced a significant decline in ROS production and a G 1 /S block that translated into a 2-3-fold increase in tumor cell doubling time without increased apoptosis. The block at the G 1 /S checkpoint was associated with a significant decrease in cyclin D 1 expression and profound inhibition of mitogen-activated protein kinase (MAPK) signaling. Decreased steady-state MAPK phosphorylation occurred concomitant with a significant increase in protein phosphatase activity for two colon cancer cell lines in which NOX1 expression was knocked down by RNAi. Diminished NOX1 expression also contributed to decreased growth, blood vessel density, and VEGF and hypoxia-inducible factor 1α (HIF-1α) expression in HT-29 xenografts initiated from NOX1 knockdown cells. Microarray analysis, supplemented by real-time PCR and Western blotting, revealed that the expression of critical regulators of cell proliferation and angiogenesis, including c-MYC, c-MYB, and VEGF, were down-regulated in association with a decline in hypoxic HIF-1α protein expression downstream of silenced NOX1 in both colon cancer cell lines and xenografts. These studies suggest a role for NOX1 in maintaining the proliferative phenotype of some colon cancers and the potential of NOX1 as a therapeutic target in this disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Gastric and colonic mantle cell lymphoma - incidental discovery.

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Pitigoi, Dan; Stoica, Victor; Stoia, Razvan; Dobrea, Camelia; Becheanu, Gabriel; Diculescu, Mircea

2009-03-01

A 65-year old patient, with no medical history, was admitted for lower gastrointestinal bleeding. On clinical examination the patient seemed to be in good health. However the examination was completed with a rectosigmoidoscopy revealing the presence of mucosal erosions, ulcerations, multiple papulae. The histopathological examination raised the suspicion of a colonic lymphoma. Gastric biopsies suggested a gastric MALT type lymphoma associated to the colonic lymphoma, but the immunohistochemical profile corresponded to a mantle cell lymphoma. In spite of the general poor prognosis of mantle cell lymphoma, our patient had a good clinical and endoscopic response to the standard cyclophosphamide, vincristine, prednisone (CVP) therapy. The cases of gastric and colonic mantle lymphoma are rare, the response to therapy is poor; fortunately, our patient had a complete resolution after completion of the six cycles of chemotherapy.

Identification of downstream metastasis-associated target genes regulated by LSD1 in colon cancer cells.

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Chen, Jiang; Ding, Jie; Wang, Ziwei; Zhu, Jian; Wang, Xuejian; Du, Jiyi

2017-03-21

This study aims to identify downstream target genes regulated by lysine-specific demethylase 1 (LSD1) in colon cancer cells and investigate the molecular mechanisms of LSD1 influencing invasion and metastasis of colon cancer. We obtained the expression changes of downstream target genes regulated by small-interfering RNA-LSD1 and LSD1-overexpression via gene expression profiling in two human colon cancer cell lines. An Affymetrix Human Transcriptome Array 2.0 was used to identify differentially expressed genes (DEGs). We screened out LSD1-target gene associated with proliferation, metastasis, and invasion from DEGs via Gene Ontology and Pathway Studio. Subsequently, four key genes (CABYR, FOXF2, TLE4, and CDH1) were computationally predicted as metastasis-related LSD1-target genes. ChIp-PCR was applied after RT-PCR and Western blot validations to detect the occupancy of LSD1-target gene promoter-bound LSD1. A total of 3633 DEGs were significantly upregulated, and 4642 DEGs were downregulated in LSD1-silenced SW620 cells. A total of 4047 DEGs and 4240 DEGs were upregulated and downregulated in LSD1-overexpressed HT-29 cells, respectively. RT-PCR and Western blot validated the microarray analysis results. ChIP assay results demonstrated that LSD1 might be negative regulators for target genes CABYR and CDH1. The expression level of LSD1 is negatively correlated with mono- and dimethylation of histone H3 lysine4(H3K4) at LSD1- target gene promoter region. No significant mono-methylation and dimethylation of H3 lysine9 methylation was detected at the promoter region of CABYR and CDH1. LSD1- depletion contributed to the upregulation of CABYR and CDH1 through enhancing the dimethylation of H3K4 at the LSD1-target genes promoter. LSD1- overexpression mediated the downregulation of CABYR and CDH1expression through decreasing the mono- and dimethylation of H3K4 at LSD1-target gene promoter in colon cancer cells. CABYR and CDH1 might be potential LSD1-target genes in colon

miR-4458 suppresses glycolysis and lactate production by directly targeting hexokinase2 in colon cancer cells

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Qin, Yaguang; Cheng, Chuanyao; Lu, Hong, E-mail: honglu6512@163.com; Wang, Yaqiu

2016-01-01

miR-4458, a new tumor-suppressor, was reported to down-regulated in human hepatocellular carcinoma. The expression status, roles and inhibitory mechanisms of miR-4458 in other tumors still need to be clarified. The aim of this study is to investigate the effects of miR-4458 and to elucidate the potential mechanism in colon cancer cells. Using bioinformatic databases, we predicted that hexokinase2 (HK2), a rate-limiting enzyme in the glycolytic pathway, was a target of miR-4458, so the effects of miR-4458 on glycolysis and lactate production was assessed in colon cancer cells. We found that miR-4458 was down-regulated and HK2 was up-regulated in colon cancer cells. Overexpression of miR-4458 inhibited proliferation, glycolysis, and lactate production under both normoxic and hypoxic conditions. Luciferase activity assays showed that HK2 was a direct target of miR-4458. Moreover, knockdown of HK2 by specific RNAi also suppressed proliferation, glycolysis, and lactate production under both normoxic and hypoxic conditions. In conclusion, our findings suggested that miR-4458 inhibited the progression of colon cancer cells by inhibition of glycolysis and lactate production via directly targeting HK2 mRNA. - Highlights: • miR-4458 is down-regulated in colon cancer cells. • miR-4458 suppresses proliferation, glycolysis, and lactate production. • HK2 is a target of miR-4458. • HK2 knockdown inhibits proliferation, glycolysis, and lactate production.

Abrogation of Gli3 expression suppresses the growth of colon cancer cells via activation of p53

International Nuclear Information System (INIS)

Kang, Han Na; Oh, Sang Cheul; Kim, Jun Suk; Yoo, Young A.

2012-01-01

p53, the major human tumor suppressor, appears to be related to sonic hedgehog (Shh)–Gli-mediated tumorigenesis. However, the role of p53 in tumor progression by the Shh–Gli signaling pathway is poorly understood. Herein we investigated the critical regulation of Gli3–p53 in tumorigenesis of colon cancer cells and the molecular mechanisms underlying these effects. RT-PCR analysis indicated that the mRNA level of Shh and Gli3 in colon tumor tissues was significantly higher than corresponding normal tissues (P < 0.001). The inhibition of Gli3 by treatment with Gli3 siRNA resulted in a clear decrease in cell proliferation and enhanced the level of expression of p53 proteins compared to treatment with control siRNA. The half-life of p53 was dramatically increased by treatment with Gli3 siRNA. In addition, treatment with MG132 blocked MDM2-mediated p53 ubiquitination and degradation, and led to accumulation of p53 in Gli3 siRNA-overexpressing cells. Importantly, ectopic expression of p53 siRNA reduced the ability of Gli3 siRNA to suppress proliferation of those cells compared with the cells treated with Gli3 siRNA alone. Moreover, Gli3 siRNA sensitized colon cancer cells to treatment with anti-cancer agents (5-FU and bevacizumab). Taken together, our studies demonstrate that loss of Gli3 signaling leads to disruption of the MDM2–p53 interaction and strongly potentiate p53-dependent cell growth inhibition in colon cancer cells, indicating a basis for the rational use of Gli3 antagonists as a novel treatment option for colon cancer.

Cytotoxicity and Apoptotic Effects of Polyphenols from Sugar Beet Molasses on Colon Carcinoma Cells in Vitro

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Mingshun Chen

2016-06-01

Full Text Available Three polyphenols were isolated and purified from sugar beet molasses by ultrasonic-aid extraction and various chromatographic techniques, and their structures were elucidated by spectral analysis. Cytotoxicity and the molecular mechanism were measured by methyl thiazolyl tetrazolium (MTT assay, flow cytometry, caspase-3 activity assay and Western blot assay. The results showed that gallic acid, cyanidin-3-O-glucoside chloride and epicatechin have cytotoxicity to the human colon, hepatocellular and breast cancer cells. Cyanidin-3-O-glucoside chloride showed its cytotoxicity against various tumor cell lines, particularly against colon cancer Caco-2 cells with half maximal inhibitory concentration (IC50 value of 23.21 ± 0.14 μg/mL in vitro. Cyanidin-3-O-glucoside chloride may be a potential candidate for the treatment of colon cancer. In the mechanism study, cyanidin-3-O-glucoside chloride increased the ratio of cell cycle at G0/G1 phase and reduced cyclin D1 expression on Caco-2 cells. Cyanidin-3-O-glucoside chloride decreased mutant p21 expression, and increased the ratio of Bax/Bcl-2 and the activation of caspase-3 to induce apoptosis.

Inhibition of autophagy induced by TSA sensitizes colon cancer cell to radiation.

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He, Gang; Wang, Yan; Pang, Xueli; Zhang, Bo

2014-02-01

Radiotherapy is one of the main treatments for clinical cancer therapy. However, its application was limited due to lack of radiosensitivity in some cancers. Trichostatin A (TSA) is a classic histone deacetylases inhibitor (HDACi) that specifically inhibits the biochemical functions of HDAC and is demonstrated to be an active anticancer drug. However, whether it could sensitize colon cancer to radiation is not clear. Our results showed that TSA enhanced the radiosensitivity of colon cancer cells as determined by CCK-8 and clonogenic survival assay. Moreover, apoptotic cell death induced by radiation was enhanced by TSA treatment. Additionally, TSA also induced autophagic response in colon cancer cells, while autophagy inhibition led to cell apoptosis and enhanced the radiosensitivity of colon cancer cells. Our data suggested that inhibition of cytoprotective autophagy sensitizes cancer cell to radiation, which might be further investigated for clinical cancer radiotherapy.

Continued colonization of the human genome by mitochondrial DNA.

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Miria Ricchetti

2004-09-01

Full Text Available Integration of mitochondrial DNA fragments into nuclear chromosomes (giving rise to nuclear DNA sequences of mitochondrial origin, or NUMTs is an ongoing process that shapes nuclear genomes. In yeast this process depends on double-strand-break repair. Since NUMTs lack amplification and specific integration mechanisms, they represent the prototype of exogenous insertions in the nucleus. From sequence analysis of the genome of Homo sapiens, followed by sampling humans from different ethnic backgrounds, and chimpanzees, we have identified 27 NUMTs that are specific to humans and must have colonized human chromosomes in the last 4-6 million years. Thus, we measured the fixation rate of NUMTs in the human genome. Six such NUMTs show insertion polymorphism and provide a useful set of DNA markers for human population genetics. We also found that during recent human evolution, Chromosomes 18 and Y have been more susceptible to colonization by NUMTs. Surprisingly, 23 out of 27 human-specific NUMTs are inserted in known or predicted genes, mainly in introns. Some individuals carry a NUMT insertion in a tumor-suppressor gene and in a putative angiogenesis inhibitor. Therefore in humans, but not in yeast, NUMT integrations preferentially target coding or regulatory sequences. This is indeed the case for novel insertions associated with human diseases and those driven by environmental insults. We thus propose a mutagenic phenomenon that may be responsible for a variety of genetic diseases in humans and suggest that genetic or environmental factors that increase the frequency of chromosome breaks provide the impetus for the continued colonization of the human genome by mitochondrial DNA.