Green tea, phytic acid, and inositol in combination reduced the incidence of azoxymethane-induced colon tumors in Fisher 344 male rats.

Science.gov (United States)

Khatiwada, Janak; Verghese, Martha; Davis, Shurrita; Williams, Leonard L

2011-11-01

Experimental as well as epidemiologic studies in human populations provide evidence that consumption of phytochemicals reduces the incidence of degenerative diseases. Green tea (GT) catechins are known for their antioxidative potential. Phytic acid (PA) also acts as a natural antioxidant and may have numerous health benefits. This experiment was designed to investigate the inhibitory effects of combinations of 1% and 2% GT, PA, and inositol (I) in reducing the incidence of azoxymethane-induced colon tumors in Fisher 344 male rats. After an acclimatization period of 1 week, nine groups of rats (15 rats per group) were initially assigned to consume AIN 93 G diet and later AIN 93 M diet after 20 weeks of age. Treatments were given in drinking water. All rats received azoxymethane injections (16 mg/kg of body weight) subcutaneously at 7 and 8 weeks of age. Rats were killed at 45 weeks of age by CO(2) euthanasia. Tumor incidence (93.76%) and the number of tumors per tumor-bearing rat ratio (2.25) were significantly (P<.05) higher in the control group compared with treatment groups. Glutathione S-transferase activity was significantly (P<.05) higher in rats fed combinations of 2% GT+PA+I and GT+PA (33.25 ± 1.23 and 29.83 ± 1.10 μmol/mL, respectively) compared with other groups. These findings suggest that the synergistic effect of the 2% level of GT, PA, and I may reduce the incidence of colon tumors and therefore have potential as a chemopreventive agent.

Chemopreventive evaluation of a Schiff base derived copper (II) complex against azoxymethane-induced colorectal cancer in rats.

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Hajrezaie, Maryam; Hassandarvish, Pouya; Moghadamtousi, Soheil Zorofchian; Gwaram, Nura Suleiman; Golbabapour, Shahram; Najihussien, Abdrabuh; Almagrami, Amel Abdullah; Zahedifard, Maryam; Rouhollahi, Elham; Karimian, Hamed; Fani, Somaye; Kamalidehghan, Behnam; Majid, Nazia Abdul; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen

2014-01-01

Based on the potential of Schiff base compounds to act as sources for the development of cancer chemotherapeutic agents, this in vivo study was performed to investigate the inhibitory properties of the synthetic Schiff base compound Cu(BrHAP)2 on colonic aberrant crypt foci (ACF). This study involved five groups of male rats. The negative control group was injected with normal saline once a week for 2 weeks and fed 10% Tween 20 for 10 weeks, the cancer control group was subcutaneously injected with 15 mg/kg azoxymethane once per week for two consecutive weeks, the positive control group was injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and 35 mg/kg 5-fluorouracil (injected intra-peritoneally) for 4 weeks, and the experimental groups were first injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and then fed 2.5 or 5 mg/kg of the Schiff base compound once a day for 10 weeks. Application of the Schiff base compound suppressed total colonic ACF formation by up to 72% to 74% (P<0.05) when compared with the cancer control group. Analysis of colorectal specimens revealed that treatments with the Schiff base compound decreased the mean crypt scores in azoxymethane-treated rats. Significant elevations of superoxide dismutase, glutathione peroxidase and catalase activities and a reduction in the level of malondialdehyde were also observed. Histologically, all treatment groups exhibited significant decreases in dysplasia compared to the cancer control group (P<0.05). Immunohistochemical staining demonstrated down-regulation of the PCNA protein. Comparative western blot analysis revealed that COX-2 and Bcl2 were up-regulated and Bax was down-regulated compared with the AOM control group. The current study demonstrated that the Cu(BrHAP)2 compound has promising chemoprotective activities that are evidenced by significant decreases in the numbers of ACFs in azoxymethane-induced colon cancer.

Chemopreventive Effects of Germinated Rough Rice Crude Extract in Inhibiting Azoxymethane-Induced Aberrant Crypt Foci Formation in Sprague-Dawley Rats

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Elnaz Saki

2017-01-01

Full Text Available Chemoprevention has become an important area in cancer research due to low success rate of current therapeutic modalities. Diet plays a vital role in the etiology of cancer. This research was carried out to study the chemopreventive properties of germinated rough rice (GRR crude extract in Sprague-Dawley rats induced with azoxymethane. Germination of rough rice causes significant changes in several chemical compositions of presently bioactive compounds. These compounds may prevent or postpone the inception of cancer. Fifty male Sprague-Dawley rats (6 weeks of age were randomly divided into 5 groups which were (G1 induced with azoxymethane (AOM and not given GRR (positive control, (G2 induced with AOM and given 2000 mg/kg GRR, (G3 induced with AOM and given 1000 mg/kg GRR, (G4 induced with AOM and given 500 mg/kg GRR, and (G5 not induced with AOM and not given GRR crude extract (negative control. To induce colon cancer, rats received two IP injections of AOM in saline (15 mg/kg for two subsequent weeks. Organs were removed and weighed. Aberrant crypt foci (ACF were evaluated histopathologically. β-Catenin expressions were determined by Western blot. Treatment with 2000 mg/kg GRR crude extract not only resulted in the greatest reduction in the size and number of ACF but also displayed the highest percentage of nondysplastic ACF. Treatment with 2000 mg/kg GRR also gave the lowest level of expression in β-catenin. Thus, GRR could be a promising dietary supplement for prevention of CRC.

Vanillin Differentially Affects Azoxymethane-Injected Rat Colon Carcinogenesis and Gene Expression

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Ho, Ket Li; Chong, Pei Pei; Yazan, Latifah Saiful

2012-01-01

Abstract Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rats were treated with vanillin orally and intraperitoneally at low and high concentrations and ACF density, multiplicity, and distribution were observed. The gene expression of 14 colorectal cancer-related genes was also studied. Results showed that vanillin consumed orally had no effect on ACF. However, high concentrations (300 mg/kg body weight) of vanillin administered through intraperitoneal injection could increase ACF density and ACF multiplicity. ACF were mainly found in the distal colon rather than in the mid-section and proximal colon. The expression of colorectal cancer biomarkers, protooncogenes, recombinational repair, mismatch repair, and cell cycle arrest, and tumor suppressor gene expression were also affected by vanillin. Vanillin was not cocarcinogenic when consumed orally. However, it was cocarcinogenic when being administered intraperitoneally at high concentration. Hence, the use of vanillin in food should be safe but might have cocarcinogenic potential when it is used in high concentration for therapeutic purposes. PMID:23216109

δ- and γ-tocopherols, but not α-tocopherol, inhibit colon carcinogenesis in azoxymethane-treated F344 rats.

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Guan, Fei; Li, Guangxun; Liu, Anna B; Lee, Mao-Jung; Yang, Zhihong; Chen, Yu-Kuo; Lin, Yong; Shih, Weichung; Yang, Chung S

2012-04-01

The cancer preventive activity of vitamin E has been extensively discussed, but the activities of specific forms of tocopherols have not received sufficient attention. Herein, we compared the activities of δ-tocopherol (δ-T), γ-T, and α-T in a colon carcinogenesis model. Male F344 rats, seven weeks old, were given two weekly subcutaneous injections of azoxymethane (AOM) each at a dose of 15 mg/kg body weight. Starting 1 week before the AOM injection, the animals were maintained on a modified AIN76A diet, or the same diet containing 0.2% of δ-T, γ-T, α-T, or a γ-T-rich mixture of tocopherols (γ-TmT), until the termination of the experiment at 8 weeks after the second AOM injection. δ-T treatment showed the strongest inhibitory effect, decreasing the numbers of aberrant crypt foci by 62%. γ-T and γ-TmT were also effective, but α-T was not. Immunohistochemical analysis showed that δ-T and γ-T treatments reduced the levels of 4-hydroxynonenal and nitrotyrosine and the expression of cyclin D1 in the colon, preserved the expression of PPAR-γ, and decreased the serum levels of prostaglandin E2 and 8-isoprostane. Supplementation with 0.2% δ-T, γ-T, or α-T increased the respective levels of tocopherols and their side-chain degradation metabolites in the serum and colon tissues. Rather high concentrations of δ-T and γ-T and their metabolites were found in colon tissues. Our study provides the first evidence for the much higher cancer preventive activity of δ-T and γ-T than α-T in a chemically induced colon carcinogenesis model. It further suggests that δ-T is more effective than γ-T. 2012 AACR

Effect of vitamin C on azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis-associated early colon cancer in mice.

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Jeon, Hee-Jin; Yeom, Yiseul; Kim, Yoo-Sun; Kim, Eunju; Shin, Jae-Ho; Seok, Pu Reum; Woo, Moon Jea; Kim, Yuri

2018-04-01

The objective of this study was to investigate the effects of vitamin C on inflammation, tumor development, and dysbiosis of intestinal microbiota in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced inflammation-associated early colon cancer mouse model. Male BALB/c mice were injected intraperitoneally with AOM [10 mg/kg body weight (b.w)] and given two 7-d cycles of 2% DSS drinking water with a 14 d inter-cycle interval. Vitamin C (60 mg/kg b.w. and 120 mg/kg b.w.) was supplemented by gavage for 5 weeks starting 2 d after the AOM injection. The vitamin C treatment suppressed inflammatory morbidity, as reflected by disease activity index (DAI) in recovery phase and inhibited shortening of the colon, and reduced histological damage. In addition, vitamin C supplementation suppressed mRNA levels of pro-inflammatory mediators and cytokines, including cyclooxygenase-2, microsomal prostaglandin E synthase-2, tumor necrosis factor-α, Interleukin (IL)-1β , and IL-6 , and reduced expression of the proliferation marker, proliferating cell nuclear antigen, compared to observations of AOM/DSS animals. Although the microbial composition did not differ significantly between the groups, administration of vitamin C improved the level of inflammation-related Lactococcus and JQ084893 to control levels. Vitamin C treatment provided moderate suppression of inflammation, proliferation, and certain inflammation-related dysbiosis in a murine model of colitis associated-early colon cancer. These findings support that vitamin C supplementation can benefit colonic health. Long-term clinical studies with various doses of vitamin C are warranted.

A novel NSAID derivative, phospho-ibuprofen, prevents AOM-induced colon cancer in rats

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OUYANG, NENGTAI; JI, PING; WILLIAMS, JENNIE L.

2013-01-01

The cancer chemopreventive properties and gastrointestinal toxicity of ibuprofen are well documented. Modification of existing NSAIDs has improved on the chemopreventive efficacy of this agent and reduced its toxicity. In this study, ibuprofen and a modified derivative (phospho-modified ibuprofen or p-ibuprofen) were used in a chemically induced model of colon cancer. Fisher 344 rats were injected with azoxymethane then treated with either ibuprofen (500 ppm) or p-ibuprofen (900 ppm) for 20 weeks to observe aberrant crypt foci (ACF) or 40 weeks to evaluate tumor incidence and multiplicity. β-catenin and p65 were measured in colonic tissues by immunofluorescence staining. Equal molar doses of ibuprofen (75 and 670 mg/kg) and p-ibuprofen (135 and 1,215 mg/kg) were administered to rats for 7 days to assess acute toxicity. The in vitro effect of p-ibuprofen on COX-2 and PGE2 synthesis, β-catenin expression and NF-κB activity were examined in RAW 264.7 macrophage and HCT 116 colon cancer cells. At week 20, p-ibuprofen and ibuprofen significantly reduced the multiplicity of ACF compared with control (pibuprofen and ibuprofen reduced the multiplicity of colon tumors compared with control (pibuprofen (670 mg/kg) and p-ibuprofen (1,215 mg/kg) resulted in stomach ulceration in 85.7% (6 out of 7) and 14.3% (1 out of 7) of rats, respectively, with pibuprofen and p-ibuprofen suppressed β-catenin nuclear translocation in colon cancer cells. In addition, p-ibuprofen but not ibuprofen inhibited NF-κB activation in colon cancer cells. Collectively, these results suggest that p-ibuprofen is a potential effective novel drug for long-term use in colon cancer prevention. PMID:23291777

Activins and their related proteins in colon carcinogenesis: insights from early and advanced azoxymethane rat models of colon cancer.

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Refaat, Bassem; El-Shemi, Adel Galal; Mohamed, Amr Mohamed; Kensara, Osama Adnan; Ahmad, Jawwad; Idris, Shakir

2016-11-11

Activin-A may exert pro- or anti-tumorigenic activities depending on cellular context. However, little is known about its role, or the other mature activin proteins, in colorectal carcinoma (CRC). This study measured the expression of activin βA- & βB-subunits, activin type IIA & IIB receptors, smads 2/3/4/6/7 and follistatin in CRC induced by azoxymethane (AOM) in rats. The results were compared with controls and disseminated according to the characteristics of histopathological lesions. Eighty male Wistar rats were allocated into 20 controls and the remaining were equally divided between short 'S-AOM' (15 weeks) and long 'L-AOM' (35 weeks) groups following injecting AOM for 2 weeks. Subsequent to gross and histopathological examinations and digital image analysis, the expression of all molecules was measured by immunohistochemistry and quantitative RT-PCR. Activin-A, activin-B, activin-AB and follistatin were measured by ELISA in serum and colon tissue homogenates. Colonic pre-neoplastic and cancerous lesions were identified in both AOM groups and their numbers and sizes were significantly (P colonic epithelial cells. There was a significantly (P cancerous tissues. Oppositely, a significant (P colonic lesions. Normal rat colon epithelial cells are capable of synthesising, controlling as well as responding to activins in a paracrine/autocrine manner. Colonic activin systems are pathologically altered during tumorigenesis and appear to be time and lesion-dependent. Activins could also be potential sensitive markers and/or molecular targets for the diagnosis and/or treatment of CRC. Further studies are required to illustrate the clinical value of activins and their related proteins in colon cancer.

Vanillin Differentially Affects Azoxymethane-Injected Rat Colon Carcinogenesis and Gene Expression

OpenAIRE

Ho, Ket Li; Chong, Pei Pei; Yazan, Latifah Saiful; Ismail, Maznah

2012-01-01

Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rat...

Strawberry Phytochemicals Inhibit Azoxymethane/Dextran Sodium Sulfate-Induced Colorectal Carcinogenesis in Crj: CD-1 Mice

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Ni Shi

2015-03-01

Full Text Available Human and experimental colon carcinogenesis are enhanced by a pro-inflammatory microenvironment. Pharmacologically driven chemopreventive agents and dietary variables are hypothesized to have future roles in the prevention of colon cancer by targeting these processes. The current study was designed to determine the ability of dietary lyophilized strawberries to inhibit inflammation-promoted colon carcinogenesis in a preclinical animal model. Mice were given a single i.p. injection of azoxymethane (10 mg kg−1 body weight. One week after injection, mice were administered 2% (w/v dextran sodium sulfate in drinking water for seven days and then an experimental diet containing chemically characterized lyophilized strawberries for the duration of the bioassay. Mice fed control diet, or experimental diet containing 2.5%, 5.0% or 10.0% strawberries displayed tumor incidence of 100%, 64%, 75% and 44%, respectively (p < 0.05. The mechanistic studies demonstrate that strawberries reduced expression of proinflammatory mediators, suppressed nitrosative stress and decreased phosphorylation of phosphatidylinositol 3-kinase, Akt, extracellular signal-regulated kinase and nuclear factor kappa B. In conclusion, strawberries target proinflammatory mediators and oncogenic signaling for the preventive efficacies against colon carcinogenesis in mice. This works supports future development of fully characterized and precisely controlled functional foods for testing in human clinical trials for this disease.

Inhibition of beta-catenin and KRAS expressions by Piper betle in azoxymethane-induced colon cancer of male Fischer 344 rats.

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Esa, Faezah; Ngah, Wan Zurinah Wan; Jamal, A Rahman A; Mohd Yusof, Yasmin Anum

2013-12-01

To investigate the chemopreventive effect of Piper betle (PB) on preneoplastic lesions (aberrant crypt foci [ACF]) induced by azoxymethane (AOM) in rats and its effect on colorectal cancer biomarkers (beta-catenin, KRAS, p53 and p21). A total of 32 male Fischer 344 rats were divided into phase 1 and phase 2 groups (8 and 24 weeks of AOM administration, respectively). Each phase was divided into 4 groups: control or normal saline (NS) (1 mL/kg), AOM (15 mg/kg body weight, once weekly for 2 weeks), PB (75 mg/kg body weight) and AOM + PB. PB was force-fed to rats a week after the second dose of AOM and NS. The colon was cut open longitudinally for methylene blue and immunohistochemistry staining. AOM administration showed formation of ACF at 8 and 24 weeks. PB, however, did not reduce ACF formation at either week, but it managed to reduce beta-catenin expression and KRAS found highly expressed in the AOM group of phase 1 rats. No immunoreactivities of p53 and p21 were detected in phase 2 rats, but instead inflammatory cells were visible in between the lesions. PB may act as a potential chemopreventive agent in the early stage of colon carcinogenesis by suppressing the expressions of beta-catenin and KRAS.

Bovine milk-derived α-lactalbumin inhibits colon inflammation and carcinogenesis in azoxymethane and dextran sodium sulfate-treated mice.

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Yamaguchi, Makoto; Takai, Shoko; Hosono, Akira; Seki, Taiichiro

2014-01-01

Cyclooxygenase-2 is expressed early in colon carcinogenesis and plays crucial role in the progress of the disease. Recently, we found that α-lactalbumin had anti-inflammatory activity by inhibiting cyclooxygenase-2. In experiment 1, we investigated the effects of α-lactalbumin on the colon carcinogenesis initiated with azoxymethane (AOM) followed by promotion with dextran sodium sulfate (DSS) in mice. Dietary treatment with α-lactalbumin decreased fecal occult blood score at 3 days after DSS intake. α-Lactalbumin also decreased the colon tumor at week 9. In experiment 2, AOM-treated mice were sacrificed at 7 days after DSS intake. The plasma and colon prostaglandin E2 (PGE2) levels in AOM/DSS-treated mice were higher than those in the DSS-treated mice without initiation by AOM. α-Lactalbumin decreased PGE2 in both plasma and colon. These results suggest that α-lactalbumin effectively inhibited colon carcinogenesis, and the inhibition may be due to the decreased PGE2 by inhibiting cyclooxygenase-2 at cancer promotion stages.

The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

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Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Al-Henhena, Nawal; Kunasegaran, Thubasni; Hasanpourghadi, Mohadeseh; Looi, Chung Yeng; Abd Malek, Sri Nurestri; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

2015-01-01

Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation

Effects of high fat fish oil and high fat corn oil diets on initiation of AOM-induced colonic aberrant crypt foci in male F344 rats

NARCIS (Netherlands)

Dommels, Y.E.M.; Heemskerk, S.; Berg, H. van den; Alink, G.M.; Bladeren, P.J. van; Ommen, B. van

2003-01-01

Modulating effects of high fat fish oil (HFFO) and high fat corn oil (HFCO) diets on azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) were studied in male F344 rats following 8 weeks of dietary treatment. The incidence of AOM-induced ACF was significantly lower in the proximal colon of

1-L-MT, an IDO inhibitor, prevented colitis-associated cancer by inducing CDC20 inhibition-mediated mitotic death of colon cancer cells.

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Liu, Xiuting; Zhou, Wei; Zhang, Xin; Ding, Yang; Du, Qianming; Hu, Rong

2018-04-01

Indoleamine 2,3-dioxygenase 1 (IDO1), known as IDO, catabolizes tryptophan through kynurenine pathway, whose activity is correlated with impaired clinical outcome of colorectal cancer. Here we showed that 1-L-MT, a canonical IDO inhibitor, suppressed proliferation of human colorectal cancer cells through inducing mitotic death. Our results showed that inhibition of IDO decreased the transcription of CDC20, which resulted in G2/M cycle arrest of HCT-116 and HT-29. Furthermore, 1-L-MT induced mitochondria injuries and caused apoptotic cancer cells. Importantly, 1-L-MT protected mice from azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon carcinogenesis, with reduced mortality, tumor number and size. What is more, IDO1-/- mice exhibited fewer tumor burdens and reduced proliferation in the neoplastic epithelium, while, 1-L-MT did not exhibit any further protective effects on IDO-/- mice, confirming the critical role of IDO and the protective effect of 1-L-MT-mediated IDO inhibition in CRC. Furthermore, 1-L-MT also alleviated CRC in Rag1-/- mice, demonstrating the modulatory effects of IDO independent of its role in modulating adaptive immunity. Taken together, our findings validated that the anti-proliferation effect of 1-L-MT in vitro and the prevention of CRC in vivo were through IDO-induced cell cycle disaster of colon cancer cells. Our results identified 1-L-MT as a promising candidate for the chemoprevention of CRC. © 2018 UICC.

MicroRNA-155 deletion promotes tumorigenesis in the azoxymethane-dextran sulfate sodium model of colon cancer

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Velázquez, Kandy T.; Enos, Reilly T.; McClellan, Jamie L.; Cranford, Taryn L.; Chatzistamou, Ioulia; Singh, Udai P.; Nagarkatti, Mitzi; Nagarkatti, Prakash S.; Fan, Daping

2016-01-01

Clinical studies have linked microRNA-155 (miR-155) expression in the tumor microenvironment to poor prognosis. However, whether miR-155 upregulation is predictive of a pro- or antitumorigenic response is unclear, as the limited preclinical data available remain controversial. We examined miR-155 expression in tumor tissue from colon cancer patients. Furthermore, we investigated the role of this microRNA in proliferation and apoptosis, inflammatory processes, immune cell populations, and transforming growth factor-β/SMAD signaling in a chemically induced (azoxymethane-dextran sulfate sodium) mouse model of colitis-associated colon cancer. We found a higher expression of miR-155 in the tumor region than in nontumor colon tissue of patients with colon cancer. Deletion of miR-155 in mice resulted in a greater number of polyps/adenomas, an increased symptom severity score, a higher grade of epithelial dysplasia, and a decrease in survival. Surprisingly, these findings were associated with an increase in apoptosis in the normal mucosa, but there was no change in proliferation. The protumorigenic effects of miR-155 deletion do not appear to be driven solely by dysregulation of inflammation, as both genotypes had relatively similar levels of inflammatory mediators. The enhanced tumorigenic response in miR-155−/− mice was associated with alterations in macrophages and neutrophils, as markers for these populations were decreased and increased, respectively. Furthermore, we demonstrated a greater activation of the transforming growth factor-β/SMAD pathway in miR-155−/− mice, which was correlated with the increased tumorigenesis. Given the multiple targets of miR-155, careful evaluation of its role in tumorigenesis is necessary prior to any consideration of its potential as a biomarker and/or therapeutic target in colon cancer. PMID:26744471

Green Tea, Phytic Acid, and Inositol in Combination Reduced the Incidence of Azoxymethane-Induced Colon Tumors in Fisher 344 Male Rats

OpenAIRE

Khatiwada, Janak; Verghese, Martha; Davis, Shurrita; Williams, Leonard L.

2011-01-01

Experimental as well as epidemiologic studies in human populations provide evidence that consumption of phytochemicals reduces the incidence of degenerative diseases. Green tea (GT) catechins are known for their antioxidative potential. Phytic acid (PA) also acts as a natural antioxidant and may have numerous health benefits. This experiment was designed to investigate the inhibitory effects of combinations of 1% and 2% GT, PA, and inositol (I) in reducing the incidence of azoxymethane-induce...

Prophylactic effects of triptolide on colon cancer development in ...

African Journals Online (AJOL)

Purpose: To investigate effects of triptolide on colon cancer cell growth and its capacity to prevent tumor development in an azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model of colon cancer. Methods: HCT116 cell viability and migration potential were assessed. Control and AOM/DSS-treated mice (with and ...

Hydrolysed inulin alleviates the azoxymethane-induced preneoplastic aberrant crypt foci by altering selected intestinal microbiota in Sprague-Dawley rats.

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Pattananandecha, Thanawat; Sirilun, Sasithorn; Duangjitcharoen, Yodsawee; Sivamaruthi, Bhagavathi Sundaram; Suwannalert, Prasit; Peerajan, Sartjin; Chaiyasut, Chaiyavat

2016-09-01

Context Inulin, a non-digestible carbohydrate isolated from Helianthus tuberosus L. (Asteraceae), has been shown to alter the gut beneficial bacteria including Lactobacillus spp. and Bifidobacteria. Inulin also influences the activities of intestinal microbiota that could prevent the colon cancer development. Objective This study determines the effect of hydrolysed inulin with different degrees of polymerisation on alteration of intestinal microbiota and their activities on azoxymethane (AOM)-induced preneoplastic aberrant crypt foci (ACF) in rats. Materials and methods Seventy-two male Sprague-Dawley rats were randomly divided into six groups (three control and three AOM-treated groups) and the animal were fed with either a normal diet or diet containing 10% of long-chain inulin (InuL) or short-chain inulin (InuS), respectively, for 17 weeks. Colon cancer was induced in rats by injecting AOM subcutaneously at the 8th and 9th week of the study period. At the end of the experiment, cecal contents of rats were examined for selected microbiota, organic acids, putrefactive compounds and microbial enzymes. ACF formation was microscopically examined. Results The inulin diets significantly increased the weight and decreased the pH of the caecal content. The rats fed with InuL-supplemented diet showed approximately 2.9- and 6.8-fold increases in the biomass of Lactobacillus spp. and Bifidobacteria, respectively. Naive and AOM-treated rats fed with inulin-supplemented diet showed ∼1.3- and ∼2.2-fold decreases in the biomass of Escherichia coli and Salmonella enterica serovar Typhi, respectively. Inulins significantly decreased the colonic concentration of phenol, p-cresol and indole. Reduction in the activity of microbial enzymes such as β-glucuronidase, azoreductase and nitroreductase were observed in inulin-treated animals. Reduction in the ACF formation has been observed in inulin-treated groups. Discussion and conclusion The present study demonstrates that dietary

Effects of calorie restriction and diet-induced obesity on murine colon carcinogenesis, growth and inflammatory factors, and microRNA expression.

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Susan E Olivo-Marston

Full Text Available Obesity is an established colon cancer risk factor, while preventing or reversing obesity via a calorie restriction (CR diet regimen decreases colon cancer risk. Unfortunately, the biological mechanisms underlying these associations are poorly understood, hampering development of mechanism-based approaches for preventing obesity-related colon cancer. We tested the hypotheses that diet-induced obesity (DIO would increase (and CR would decrease colon tumorigenesis in the mouse azoxymethane (AOM model. In addition, we established that changes in inflammatory cytokines, growth factors, and microRNAs are associated with these energy balance-colon cancer links, and thus represent mechanism-based targets for colon cancer prevention. Mice were injected with AOM once a week for 5 weeks and randomized to: 1 control diet; 2 30% CR diet; or 3 DIO diet. Mice were euthanized at week 5 (n = 12/group, 10 (n = 12/group, and 20 (n = 20/group after the last AOM injection. Colon tumors were counted, and cytokines, insulin-like growth factor 1 (IGF-1, IGF binding protein 3 (IGFBP-3, adipokines, proliferation, apoptosis, and expression of microRNAs (miRs were measured. The DIO diet regimen induced an obese phenotype (∼36% body fat, while CR induced a lean phenotype (∼14% body fat; controls were intermediate (∼26% body fat. Relative to controls, DIO increased (and CR decreased the number of colon tumors (p = 0.01, cytokines (p<0.001, IGF-1 (p = 0.01, and proliferation (p<0.001. DIO decreased (and CR increased IGFBP-3 and apoptosis (p<0.001. miRs including mir-425, mir-196, mir-155, mir-150, mir-351, mir-16, let-7, mir34, and mir-138 were differentially expressed between the dietary groups. We conclude that the enhancing effects of DIO and suppressive effects of CR on colon carcinogenesis are associated with alterations in several biological pathways, including inflammation, IGF-1, and microRNAs.

NoxO1 Controls Proliferation of Colon Epithelial Cells

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Franziska Moll

2018-05-01

Full Text Available AimReactive oxygen species (ROS produced by enzymes of the NADPH oxidase family serve as second messengers for cellular signaling. Processes such as differentiation and proliferation are regulated by NADPH oxidases. In the intestine, due to the exceedingly fast and constant renewal of the epithelium both processes have to be highly controlled and balanced. Nox1 is the major NADPH oxidase expressed in the gut, and its function is regulated by cytosolic subunits such as NoxO1. We hypothesize that the NoxO1-controlled activity of Nox1 contributes to a proper epithelial homeostasis and renewal in the gut.ResultsNoxO1 is highly expressed in the colon. Knockout of NoxO1 reduces the production of superoxide in colon crypts and is not subsidized by an elevated expression of its homolog p47phox. Knockout of NoxO1 increases the proliferative capacity and prevents apoptosis of colon epithelial cells. In mouse models of dextran sulfate sodium (DSS-induced colitis and azoxymethane/DSS induced colon cancer, NoxO1 has a protective role and may influence the population of natural killer cells.ConclusionNoxO1 affects colon epithelium homeostasis and prevents inflammation.

The Role of Curcumin in Modulating Colonic Microbiota During Colitis and Colon Cancer Prevention

Science.gov (United States)

McFadden, Rita-Marie T.; Larmonier, Claire B.; Shehab, Kareem W.; Midura-Kiela, Monica; Ramalingam, Rajalakshmy; Harrison, Christy A.; Besselsen, David G.; Chase, John H.; Caporaso, J. Gregory; Jobin, Christian; Ghishan, Fayez K.; Kiela, Pawel R.

2015-01-01

Background Intestinal microbiota influences the progression of colitis-associated colorectal cancer (CAC). With diet being a key determinant of the gut microbial ecology, dietary interventions are an attractive avenue for the prevention of CAC. Curcumin is the most active constituent of the ground rhizome of the Curcuma Longa plant, which has been demonstrated to have anti-inflammatory, anti-oxidative and anti-proliferative properties. Methods Il10−/− mice on 129/SvEv background were used as a model of CAC. Starting at 10 weeks of age, WT or Il10−/− mice received six weekly i.p. injections of azoxymethane (AOM) or saline, and were started on either a control or curcumin-supplemented diet. Stools were collected every 4 weeks for microbial community analysis. Mice were sacrificed at 30 weeks of age. Results Curcumin-supplemented diet increased survival, decreased colon weight/length ratio, and at 0.5%, entirely eliminated tumor burden. Although colonic histology indicated improvement with curcumin, no effects of mucosal immune responses have been observed in PBS/Il10−/− mice, and limited effects were seen in AOM/Il10−/− mice. In WT and in Il10−/− mice, curcumin increased bacterial richness, prevented age-related decrease in alpha diversity, increased the relative abundance of Lactobacillales, and decreased Coriobacterales order. Taxonomic profile of AOM/Il10−/− mice receiving curcumin was more similar to those of wild-type mice than those fed control diet. Conclusions In AOM/Il10−/− model, curcumin reduced or eliminated colonic tumor burden with limited effects on mucosal immune responses. The beneficial effect of curcumin on tumorigenesis was associated with the maintenance of a more diverse colonic microbial ecology. PMID:26218141

15-Hydroxyprostaglandin dehydrogenase inactivation as a mechanism of resistance to celecoxib chemoprevention of colon tumors.

LENUS (Irish Health Repository)

Yan, Min

2009-06-09

Pharmacologic inhibitors of the prostaglandin-synthesizing COX-2 oncogene prevent the development of premalignant human colon adenomas. However, resistance to treatment is common. In this study, we show that the adenoma prevention activity of the COX-2 inhibitor celecoxib requires the concomitant presence of the 15-hydroxyprostaglandin dehydrogenase (15-PGDH) tumor suppressor gene, and that loss of 15-PGDH expression imparts resistance to celecoxib\\'s anti-tumor effects. We first demonstrate that the adenoma-preventive activity of celecoxib is abrogated in mice genetically lacking 15-PGDH. In FVB mice, celecoxib prevents 85% of azoxymethane-induced tumors >1 mm in size, but is essentially inactive in preventing tumor induction in 15-PGDH-null animals. Indeed, celecoxib treated 15-PGDH null animals develop more tumors than do celecoxib naive WT mice. In parallel with the loss of tumor prevention activity, celecoxib-mediated suppression of colonic PGE(2) levels is also markedly attenuated in 15-PGDH-null versus WT mice. Finally, as predicted by the murine models, humans with low colonic 15-PGDH levels also exhibit celecoxib resistance. Specifically, in a colon adenoma prevention trial, in all cases tested, individuals who developed new adenomas while receiving celecoxib treatment were also found as having low colonic 15-PGDH levels.

Lack of adrenomedullin results in microbiota changes and aggravates azoxymethane and dextran sulfate sodium-induced colitis in mice

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Sonia Martinez-Herrero

2016-11-01

Full Text Available The link between intestinal inflammation, microbiota, and colorectal cancer (CRC is intriguing and the potential underlying mechanisms remain unknown. Here we evaluate the influence of adrenomedullin (AM in microbiota composition and its impact on colitis with an inducible knockout (KO mouse model for AM. Microbiota composition was analyzed in KO and wild type (WT mice by pyrosequencing. Colitis was induced in mice by administration of azoxymethane (AOM followed by dextran sulfate sodium (DSS in the drinking water. Colitis was evaluated using a clinical symptoms index, histopathological analyses, and qRT-PCR. Abrogation of the adm gene in the whole body was confirmed by PCR and qRT-PCR. KO mice exhibit significant changes in colonic microbiota: higher proportion of δ-Proteobacteria class; of Coriobacteriales order; and of other families and genera was observed in KO feces. Meanwhile these mice had a lower proportion of beneficial bacteria, such as Lactobacillus gasseri and Bifidobacterium choerinum. TLR4 gene expression was higher (p<0.05 in KO animals. AM deficient mice treated with DSS exhibited a significantly worse colitis with profound weight loss, severe diarrhea, rectal bleeding, colonic inflammation, edema, infiltration, crypt destruction, and higher levels of pro-inflammatory cytokines. No changes were observed in the expression levels of adhesion molecules. In conclusion, we have shown that lack of AM leads to changes in gut microbiota population and in a worsening of colitis conditions, suggesting that endogenous AM is a protective mediator in this pathology.

Comparative DNA adduct formation and induction of colonic aberrant crypt foci in mice exposed to 2-amino-9H-pyrido[2,3-b]indole, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline and azoxymethane

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Kim, Sangyub; Guo, Jingshu; O’Sullivan, M. Gerald; Gallaher, Daniel D.; Turesky, Robert J.

2015-01-01

Considerable evidence suggests that environmental factors, including diet and cigarette smoke, are involved in the pathogenesis of colon cancer. Carcinogenic nitroso compounds (NOC), such as N-nitrosodimethylamine (NDMA), are present in tobacco and processed red meat, and NOC have been implicated in colon cancer. Azoxymethane (AOM), commonly used for experimental colon carcinogenesis, is an isomer of NDMA, and it produces the same DNA adducts as does NDMA. Heterocyclic aromatic amines (HAAs) formed during the combustion of tobacco and high-temperature cooking of meats are also associated with an elevated risk of colon cancer. The most abundant carcinogenic HAA formed in tobacco smoke is 2-amino-9H-pyrido[2,3-b]indole (AαC), whereas 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) is the most potent carcinogenic HAA formed during the cooking of meat and fish. However, the comparative tumor-initiating potential of AαC, MeIQ, and AOM is unknown. In this report, we evaluate the formation of DNA adducts as a measure of genotoxicity, and the induction of colonic aberrant crypt foci (ACF) and dysplastic ACF, as an early measure of carcinogenic potency of these compounds in the colon of male A/J mice. Both AαC and AOM induced a greater number of DNA adducts than MeIQ in the liver and colon. AOM induced a greater number of ACF and dysplastic ACF than either AαC or MeIQ. Conversely, based on adduct levels, MeIQ-DNA adducts were more potent than AαC- and AOM-DNA adducts at inducing ACF. Long-term feeding studies are required to relate levels of DNA adducts, induction of ACF, and colon cancer by these colon genotoxicants. PMID:26734915

Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

International Nuclear Information System (INIS)

Liu, Wei-Xin; Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen; Gu, Shou-Zhi; Sang, Li-Xuan; Dai, Cong; Wang, Hai-Lan

2015-01-01

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory

Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

Energy Technology Data Exchange (ETDEWEB)

Liu, Wei-Xin, E-mail: weixinliu@yahoo.com [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Gu, Shou-Zhi [Department of Anatomy, Seirei Christopher College, Hamamatsu 433-8558 (Japan); Sang, Li-Xuan [Department of Cadre Ward II, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Dai, Cong [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Hai-Lan [Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, Guangdong (China)

2015-04-10

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory

Secondary effects induced by the colon carcinogen azoxymethane in BDIX rats

DEFF Research Database (Denmark)

Kobaek-Larsen, Morten; Fenger, Claus; Ritskes-Hoitinga, Jelmera

2004-01-01

resulted in colon carcinomas with a high frequency (75-100%) and with a high reproducibility. However, some serious side effects are associated with this carcinogen treatment. In addition to the colorectal tumours, we found small intestinal tumours, hepatic lesions and a high frequency of mesenchymal renal...... the secondary effects of the induction of colon cancer by AOM, it is advisable to use male rats only and a maximum latency period of 32 weeks....

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.

Effect of dietary galacto-oligosaccharides on azoxymethane-induced aberrant crypt foci and colorectal cancer in Fischer 344 rats

NARCIS (Netherlands)

Wijnands, M.V.W.; Schoterman, H.C.; Bruijntjes, J.P.; Hollanders, V.M.H.; Woutersen, R.A.

2001-01-01

The aim of the present study was to investigate the effects of galacto-oligosaccharides (GOS, Elix'or) on the development of aberrant crypt foci (ACF) and colorectal tumours in rats treated with azoxymethane (AOM). Two groups of 102 male Fischer 344 rats were injected twice with AOM to induce

Fatty acid and lipidomic data in normal and tumor colon tissues of rats fed diets with and without fish oil

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Zora Djuric

2017-08-01

Full Text Available Data is provided to show the detailed fatty acid and lipidomic composition of normal and tumor rat colon tissues. Rats were fed either a Western fat diet or a fish oil diet, and half the rats from each diet group were treated with chemical carcinogens that induce colon cancer (azoxymethane and dextran sodium sulfate. The data show total fatty acid profiles of sera and of all the colon tissues, namely normal tissue from control rats and both normal and tumor tissues from carcinogen-treated rats, as obtained by gas chromatography with mass spectral detection. Data from lipidomic analyses of a representative subset of the colon tissue samples is also shown in heat maps generated from hierarchical cluster analysis. These data display the utility lipidomic analyses to enhance the interpretation of dietary feeding studies aimed at cancer prevention and support the findings published in the companion paper (Effects of fish oil supplementation on prostaglandins in normal and tumor colon tissue: modulation by the lipogenic phenotype of colon tumors, Djuric et al., 2017 [1].

Goniothalamin prevents the development of chemically induced and spontaneous colitis in rodents and induces apoptosis in the HT-29 human colon tumor cell line

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Vendramini-Costa, Débora Barbosa, E-mail: vendramini.debora@gmail.com [Department of Organic Chemistry, Institute of Chemistry, University of Campinas, Campinas, SP (Brazil); Chemical, Biological and Agricultural Pluridisciplinary Research Center (CPQBA), University of Campinas, Campinas, SP (Brazil); Alcaide, Antonio [Department of Pharmacology, Faculty of Pharmacy, University of Seville, Seville (Spain); Pelizzaro-Rocha, Karin Juliane [Department of Biochemistry, Institute of Biology, University of Campinas, Campinas, SP (Brazil); Talero, Elena; Ávila-Román, Javier [Department of Pharmacology, Faculty of Pharmacy, University of Seville, Seville (Spain); Garcia-Mauriño, Sofia [Department of Plant Biology and Ecology, Faculty of Biology, University of Seville, Seville (Spain); Pilli, Ronaldo Aloise [Department of Organic Chemistry, Institute of Chemistry, University of Campinas, Campinas, SP (Brazil); Carvalho, João Ernesto de [Chemical, Biological and Agricultural Pluridisciplinary Research Center (CPQBA), University of Campinas, Campinas, SP (Brazil); Faculty of Pharmaceutical Sciences, University of Campinas, Campinas, SP (Brazil); Motilva, Virginia [Department of Pharmacology, Faculty of Pharmacy, University of Seville, Seville (Spain)

2016-06-01

Colon cancer is the third most incident type of cancer worldwide. One of the most important risk factors for colon cancer development are inflammatory bowel diseases (IBD), thus therapies focusing on IBD treatment have great potential to be used in cancer prevention. Nature has been a source of new therapeutic and preventive agents and the racemic form of the styryl-lactone goniothalamin (GTN) has been shown to be a promising antiproliferative agent, with gastroprotective, antinociceptive and anti-inflammatory effects. As inflammation is a well-known tumor promoter, the major goal of this study was to evaluate the therapeutic and preventive potentials of GTN on chemically induced and spontaneous colitis, as well as the cytotoxic effects of GTN on a human colon tumor cell line (HT-29). GTN treatments inhibited TNBS-induced acute and chronic colitis development in Wistar rats, reducing myeloperoxidase levels and inflammatory cells infiltration in the mucosa. In spontaneous-colitis using IL-10 deficient mice (C57BL/6 background), GTN prevented colitis development through downregulation of TNF-α, upregulation of SIRT-1 and inhibition of proliferation (PCNA index), without signs of toxicity after three months of treatment. In HT-29 cells, treatment with 10 μM of GTN induced apoptosis by increasing BAX/BCL2, p-JNK1/JNK1, p-P38/P38 ratios as well as through ROS generation. Caspase 8, 9 and 3 activation also occurred, suggesting caspase-dependent apoptotic pathway, culminating in PARP-1 cleavage. Together with previous data, these results show the importance of GTN as a pro-apoptotic, preventive and therapeutic agent for IBD and highlight its potential as a chemopreventive agent for colon cancer. - Highlights: • Goniothalamin (GTN) inhibits the development of TNBS-induced colitis in rats. • Moreover, GTN prevents the development of spontaneous colitis in IL-10 deficient mice. • This activity relies on downregulation of TNF-α and upregulation of SIRT-1 expression

Cathelicidin suppresses colon cancer development by inhibition of cancer associated fibroblasts

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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

Korean Solar Salt Ameliorates Colon Carcinogenesis in an AOM/DSS-Induced C57BL/6 Mouse Model.

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Ju, Jaehyun; Kim, Yeung-Ju; Park, Eui Seong; Park, Kun-Young

2017-06-01

The effects of Korean solar salt on an azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon cancer C57BL/6 mouse model were studied. Korean solar salt samples (SS-S, solar salt from S salt field; SS-Yb, solar salt from Yb salt field), nine-time-baked bamboo salt (BS-9x, made from SS-Yb), purified salt (PS), and SS-G (solar salt from Guérande, France) were orally administered at a concentration of 1% during AOM/DSS colon cancer induction, and compared for their protective effects during colon carcinogenesis in C57BL/6 mice. SS-S and SS-Yb suppressed colon length shortening and tumor counts in mouse colons. Histological evaluation by hematoxylin and eosin staining also revealed suppression of tumorigenesis by SS-S. Conversely, PS and SS-G did not show a similar suppressive efficacy as Korean solar salt. SS-S and SS-Yb promoted colon mRNA expression of an apoptosis-related factor and cell-cycle-related gene and suppressed pro-inflammatory factor. SS-Yb baked into BS-9x further promoted these anti-carcinogenic efficacies. Taken together, the results indicate that Korean solar salt, especially SS-S and SS-Yb, exhibited anti-cancer activity by modulating apoptosis- and inflammation-related gene expression during colon carcinogenesis in mice, and bamboo salt baked from SS-Yb showed enhanced anti-cancer functionality.

Refined carbohydrate enhancement of aberrant crypt foci (ACF) in rat colon induced by the food-borne carcinogen 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ)

DEFF Research Database (Denmark)

Kristiansen, E.; Meyer, Otto A.; Thorup, I.

1996-01-01

,2-dimethylhydrazine dihydrochloride (DMH) and azoxymethane (AOM), the use of a diet-related colon cancer initiator, such as the heterocyclic amine 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) formed during meat cooking, would probably give a more relevant insight into diet-related colon carcinogenesis......The aberrant crypt foci (ACF) bioassay has been used extensively to study the early effects of different dietary components on the colonic mucosa of laboratory rodents. ACF are proposed to represent preneoplastic lesions of colon cancer. Compared to the normally used initiators 1....... In the present study it is shown that a feeding regimen with continuous low IQ doses (0.03% in the diet) throughout a study period of 10 weeks has a significant effect on the induction of ACF in the colon of male F344 rats. In addition, the study illustrates that the incidence of the IQ-induced ACF can...

Chemoprevention of Colonic Aberrant Crypt Foci by Novel Schiff Based Dichlorido(4-Methoxy-2-{[2-(Piperazin-4-Ium-1-Yl)Ethyl]Iminomethyl}Phenolate)Cd Complex in Azoxymethane-Induced Colorectal Cancer in Rats

Science.gov (United States)

Hajrezaie, Maryam; Shams, Keivan; Moghadamtousi, Soheil Zorofchian; Karimian, Hamed; Hassandarvish, Pouya; Emtyazjoo, Mozhgan; Zahedifard, Maryam; Majid, Nazia Abdul; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen

2015-01-01

Schiff-based complexes as a source of cancer chemotherapeutic compounds have been subjected to the variety of anticancer studies. The in-vitro analysis confirmed the CdCl2(C14H21N3O2) complex possess cytotoxicity and apoptosis induction properties in colon cancer cells, so lead to investigate the inhibitory efficiency of the compound on colonic aberrant crypt foci (ACF). Five groups of adult male rats were used in this study: Vehicle, cancer control, positive control groups and the groups treated with 25 and 50 mg/kg of complex for 10 weeks. The rats in vehicle group were injected subcutaneously with 15 mg/kg of sterile normal saline once a week for 2 weeks and orally administered with 5% Tween-20 (5 ml/kg) for 10 weeks, other groups were injected subcutaneously with 15 mg/kg azoxymethane once a week for 2 weeks. The rats in positive groups were injected intra-peritoneally with 35 mg/kg 5-Flourouracil four times in a month. Administration of the complex suppressed total colonic ACF formation up to 73.4% (P < 0.05). The results also showed that treatment with the complex significantly reduced the level of malondialdehyde while increasing superoxide dismutase and catalase activities. Furthermore, the down-regulation of PCNA and Bcl2 and the up-regulation of Bax was confirmed by immunohistochemical staining. PMID:26201720

Synthetic triterpenoid induces 15-PGDH expression and suppresses inflammation-driven colon carcinogenesis.

Science.gov (United States)

Choi, Sung Hee; Kim, Byung-Gyu; Robinson, Janet; Fink, Steve; Yan, Min; Sporn, Michael B; Markowitz, Sanford D; Letterio, John J

2014-06-01

Colitis-associated colon cancer (CAC) develops as a result of inflammation-induced epithelial transformation, which occurs in response to inflammatory cytokine-dependent downregulation of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and subsequent suppression of prostaglandin metabolism. Agents that both enhance 15-PGDH expression and suppress cyclooxygenase-2 (COX-2) production may more effectively prevent CAC. Synthetic triterpenoids are a class of small molecules that suppress COX-2 as well as inflammatory cytokine signaling. Here, we found that administration of the synthetic triterpenoid 2-cyano-3,12-dioxooleana-1,9(11)-dien-C28-methyl ester (CDDO-Me) suppresses CAC in mice. In a spontaneous, inflammation-driven intestinal neoplasia model, deletion of Smad4 specifically in T cells led to progressive production of inflammatory cytokines, including TNF-α, IFN-γ, iNOS, IL-6, IL-1β; as well as activation of STAT1 and STAT3; along with suppression of 15-PGDH expression. Oral administration of CDDO-Me to mice with SMAD4-deficient T cells increased survival and suppressed intestinal epithelial neoplasia by decreasing production of inflammatory mediators and increasing expression of 15-PGDH. Induction of 15-PGDH by CDDO-Me was dose dependent in epithelial cells and was abrogated following treatment with TGF-β signaling inhibitors in vitro. Furthermore, CDDO-Me-dependent 15-PGDH induction was not observed in Smad3-/- mice. Similarly, CDDO-Me suppressed azoxymethane plus dextran sodium sulfate-induced carcinogenesis in wild-type animals, highlighting the potential of small molecules of the triterpenoid family as effective agents for the chemoprevention of CAC in humans.

The flavonoid compound apigenin prevents colonic inflammation and motor dysfunctions associated with high fat diet-induced obesity.

Science.gov (United States)

Gentile, Daniela; Fornai, Matteo; Colucci, Rocchina; Pellegrini, Carolina; Tirotta, Erika; Benvenuti, Laura; Segnani, Cristina; Ippolito, Chiara; Duranti, Emiliano; Virdis, Agostino; Carpi, Sara; Nieri, Paola; Németh, Zoltán H; Pistelli, Laura; Bernardini, Nunzia; Blandizzi, Corrado; Antonioli, Luca

2018-01-01

Apigenin can exert beneficial actions in the prevention of obesity. However, its putative action on obesity-associated bowel motor dysfunctions is unknown. This study examined the effects of apigenin on colonic inflammatory and motor abnormalities in a mouse model of diet-induced obesity. Male C57BL/6J mice were fed with standard diet (SD) or high-fat diet (HFD). SD or HFD mice were treated with apigenin (10 mg/Kg/day). After 8 weeks, body and epididymal fat weight, as well as cholesterol, triglycerides and glucose levels were evaluated. Malondialdehyde (MDA), IL-1β and IL-6 levels, and let-7f expression were also examined. Colonic infiltration by eosinophils, as well as substance P (SP) and inducible nitric oxide synthase (iNOS) expressions were evaluated. Motor responses elicited under blockade of NOS and tachykininergic contractions were recorded in vitro from colonic longitudinal muscle preparations. When compared to SD mice, HFD animals displayed increased body weight, epididymal fat weight and metabolic indexes. HFD mice showed increments in colonic MDA, IL-1β and IL-6 levels, as well as a decrease in let-7f expression in both colonic and epididymal tissues. HFD mice displayed an increase in colonic eosinophil infiltration. Immunohistochemistry revealed an increase in SP and iNOS expression in myenteric ganglia of HFD mice. In preparations from HFD mice, electrically evoked contractions upon NOS blockade or mediated by tachykininergic stimulation were enhanced. In HFD mice, Apigenin counteracted the increase in body and epididymal fat weight, as well as the alterations of metabolic indexes. Apigenin reduced also MDA, IL-1β and IL-6 colonic levels as well as eosinophil infiltration, SP and iNOS expression, along with a normalization of electrically evoked tachykininergic and nitrergic contractions. In addition, apigenin normalized let-7f expression in epididymal fat tissues, but not in colonic specimens. Apigenin prevents systemic metabolic alterations

Chemopreventive and Antioxidant Effect of Polyphenol Free Spirulina maxima and Its Hydrolyzed Protein Content: Investigation on Azoxymethane Treated Mice.

Science.gov (United States)

Martínez-Palma, Nikte Y; Dávila-Ortiz, Gloria; Jiménez-Martínez, Cristian; Madrigal-Bujaidar, Eduardo; Álvarez-González, Isela

2017-07-01

Spirulina maxima (Sm) is known to have nutritive value as well as a number of potentially useful biomedical properties. The initial purpose of this report was to evaluate the inhibitory effect of the alga (without its polyphenol content), on the induction of azoxymethane (AOM)-induced colon aberrant crypts (AC) in mouse. Besides, we hydrolyzed the protein content of such mixture. Our second aim was to determine the inhibitory potential of this last plant mixture on the AOM-induced colon AC in mouse. Moreover, we also determined the effect of the two indicated Sm samples on the oxidative damage caused by AOM in the colon and liver of treated mice. The experiment lasted 5 weeks. At the end, we registered the level of AC, nitric oxide, and the lipid and protein oxidation. Our results showed the following: (1) the carcinogen increased more than 18 times the amount of the AC found in the control group. (2) On the contrary, the two tested mixtures of Sm produced a significant reduction over this damage (about 45%). (3) The two tested Sm mixtures were generally able to reduce the oxidative stress markers although with variable effects which go from 59% to 100% with respect to the control mice. Therefore, the present report established that the tested Sm fractions have mouse colon anticarcinogenic potential, partially related with their antioxidant capacity. Our report also suggested the need to further evaluate specific Sm chemicals as chemopreventive agents.

Prophylactic effects of triptolide on colon cancer development in ...

African Journals Online (AJOL)

tumor development in an azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model of colon ... pancreas, the expression levels of peroxisome ... diterpenoid molecule [16-18]. Biological investigations of triptolide have revealed its.

High Endogenous Expression of Chitinase 3-Like 1 and Excessive Epithelial Proliferation with Colonic Tumor Formation in MOLF/EiJ Mice.

Directory of Open Access Journals (Sweden)

Daren Low

Full Text Available Colorectal cancer (CRC development is mediated by uncontrolled survival and proliferation of tumor progenitor cells. Using animal models to identify and study host-derived factors that underlie this process can aid interventions in preventing tumor expansion and metastasis. In healthy steady states in humans and mice (e.g. C57BL/6 strain, colonic Chitinase 3-like 1 (CHI3L1 gene expression is undetectable. However, this expression can be induced during intestinal inflammation and tumorigenesis where CHI3L1 plays an important role in tissue restitution and cell proliferation. Here, we show that a wild-derived mouse strain MOLF/EiJ expresses high levels of colonic epithelial CHI3L1 at the steady state due to several nucleotide polymorphisms in the proximal promoter regions of the CHI3L1 gene. Interestingly, these mice spontaneously developed polypoid nodules in the colon with signs of immune cell infiltrations at steady state. The CHI3L1 positive colonic epithelial cells were highly proliferative and exhibited malignant transformation and expansion when exposed in vivo to azoxymethane, one of the well-known colonic carcinogens.

Red Wine and Pomegranate Extracts Suppress Cured Meat Promotion of Colonic Mucin-Depleted Foci in Carcinogen-Induced Rats.

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Bastide, Nadia M; Naud, Nathalie; Nassy, Gilles; Vendeuvre, Jean-Luc; Taché, Sylviane; Guéraud, Françoise; Hobbs, Ditte A; Kuhnle, Gunter G; Corpet, Denis E; Pierre, Fabrice H F

2017-01-01

Processed meat intake is carcinogenic to humans. We have shown that intake of a workshop-made cured meat with erythorbate promotes colon carcinogenesis in rats. We speculated that polyphenols could inhibit this effect by limitation of endogenous lipid peroxidation and nitrosation. Polyphenol-rich plant extracts were added to the workshop-made cured meat and given for 14 days to rats and 100 days to azoxymethane-induced rats to evaluate the inhibition of preneoplastic lesions. Colons of 100-d study were scored for precancerous lesions (mucin-depleted foci, MDF), and biochemical end points of peroxidation and nitrosation were measured in urinary and fecal samples. In comparison with cured meat-fed rats, dried red wine, pomegranate extract, α-tocopherol added at one dose to cured meat and withdrawal of erythorbate significantly decreased the number of MDF per colon (but white grape and rosemary extracts did not). This protection was associated with the full suppression of fecal excretion of nitrosyl iron, suggesting that this nitroso compound might be a promoter of carcinogenesis. At optimized concentrations, the incorporation of these plant extracts in cured meat might reduce the risk of colorectal cancer associated with processed meat consumption.

Oral administration of a recombinant cholera toxin B subunit promotes mucosal healing in the colon.

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Baldauf, K J; Royal, J M; Kouokam, J C; Haribabu, B; Jala, V R; Yaddanapudi, K; Hamorsky, K T; Dryden, G W; Matoba, N

2017-07-01

Cholera toxin B subunit (CTB) is a component of a licensed oral cholera vaccine. However, CTB has pleiotropic immunomodulatory effects whose impacts on the gut are not fully understood. Here, we found that oral administration in mice of a plant-made recombinant CTB (CTBp) significantly increased several immune cell populations in the colon lamina propria. Global gene expression analysis revealed that CTBp had more pronounced impacts on the colon than the small intestine, with significant activation of TGFβ-mediated pathways in the colon epithelium. The clinical relevance of CTBp-induced impacts on colonic mucosa was examined. In a human colon epithelial model using Caco2 cells, CTBp, but not the non-GM1-binding mutant G33D-CTBp, induced TGFβ-mediated wound healing. In a dextran sodium sulfate (DSS) acute colitis mouse model, oral administration of CTBp protected against colon mucosal damage as manifested by mitigated body weight loss, decreased histopathological scores, and blunted escalation of inflammatory cytokine levels while inducing wound healing-related genes. Furthermore, biweekly oral administration of CTBp significantly reduced disease severity and tumorigenesis in the azoxymethane/DSS model of ulcerative colitis and colon cancer. Altogether, these results demonstrate CTBp's ability to enhance mucosal healing in the colon, highlighting its potential application in ulcerative colitis therapy besides cholera vaccination.

The chemopreventive action of bromelain, from pineapple stem (Ananas comosus L.), on colon carcinogenesis is related to antiproliferative and proapoptotic effects.

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Romano, Barbara; Fasolino, Ines; Pagano, Ester; Capasso, Raffaele; Pace, Simona; De Rosa, Giuseppe; Milic, Natasa; Orlando, Pierangelo; Izzo, Angelo A; Borrelli, Francesca

2014-03-01

Colorectal cancer is an important health problem across the world. Here, we investigated the possible antiproliferative/proapoptotic effects of bromelain (from the pineapple stem Ananas comosus L., family Bromeliaceae) in a human colorectal carcinoma cell line and its potential chemopreventive effect in a murine model of colon cancer. Proliferation and apoptosis were evaluated in human colon adenocarcinoma (Caco-2) cells by the (3) H-thymidine incorporation assay and caspase 3/7 activity measurement, respectively. Extracellular signal-related kinase (ERK) and Akt expression were evaluated by Western blot analysis, reactive oxygen species production by a fluorimetric method. In vivo, bromelain was evaluated using the azoxymethane murine model of colon carcinogenesis. Bromelain reduced cell proliferation and promoted apoptosis in Caco-2 cells. The effect of bromelain was associated to downregulation of pERK1/2/total, ERK, and pAkt/Akt expression as well as to reduction of reactive oxygen species production. In vivo, bromelain reduced the development of aberrant crypt foci, polyps, and tumors induced by azoxymethane. Bromelain exerts antiproliferative and proapoptotic effects in colorectal carcinoma cells and chemopreventive actions in colon carcinogenesis in vivo. Bromelain-containing foods and/or bromelain itself may represent good candidates for colorectal cancer chemoprevention. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nuclear Magnetic Resonance-Based Metabolomics Approach to Evaluate the Prevention Effect of Camellia nitidissima Chi on Colitis-Associated Carcinogenesis

Directory of Open Access Journals (Sweden)

Ming-Hui Li

2017-07-01

Full Text Available Colorectal cancer (CRC is one of the most common malignant tumors worldwide, occurring in the colon or rectum portion of large intestine. With marked antioxidant, anti-inflammation and anti-tumor activities, Camellia nitidissima Chi has been used as an effective treatment of cancer. The azoxymethane/dextran sodium sulfate (AOM/DSS induced CRC mice model was established and the prevention effect of C. nitidissima Chi extracts on the evolving of CRC was evaluated by examination of neoplastic lesions, histopathological inspection, serum biochemistry analysis, combined with nuclear magnetic resonance (NMR-based metabolomics and correlation network analysis. C. nitidissima Chi extracts could significantly inhibit AOM/DSS induced CRC, relieve the colonic pathology of inflammation and ameliorate the serum biochemistry, and could significantly reverse the disturbed metabolic profiling toward the normal state. Moreover, the butanol fraction showed a better efficacy than the water-soluble fraction of C. nitidissima Chi. Further development of C. nitidissima Chi extracts as a potent CRC inhibitor was warranted.

15-Hydroxyprostaglandin dehydrogenase is an in vivo suppressor of colon tumorigenesis.

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Myung, Seung-Jae; Rerko, Ronald M; Yan, Min; Platzer, Petra; Guda, Kishore; Dotson, Angela; Lawrence, Earl; Dannenberg, Andrew J; Lovgren, Alysia Kern; Luo, Guangbin; Pretlow, Theresa P; Newman, Robert A; Willis, Joseph; Dawson, Dawn; Markowitz, Sanford D

2006-08-08

15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is a prostaglandin-degrading enzyme that is highly expressed in normal colon mucosa but is ubiquitously lost in human colon cancers. Herein, we demonstrate that 15-PGDH is active in vivo as a highly potent suppressor of colon neoplasia development and acts in the colon as a required physiologic antagonist of the prostaglandin-synthesizing activity of the cyclooxygenase 2 (COX-2) oncogene. We first show that 15-PGDH gene knockout induces a marked 7.6-fold increase in colon tumors arising in the Min (multiple intestinal neoplasia) mouse model. Furthermore, 15-PGDH gene knockout abrogates the normal resistance of C57BL/6J mice to colon tumor induction by the carcinogen azoxymethane (AOM), conferring susceptibility to AOM-induced adenomas and carcinomas in situ. Susceptibility to AOM-induced tumorigenesis is mediated by a marked induction of dysplasia, proliferation, and cyclin D1 expression throughout microscopic aberrant crypt foci arising in 15-PGDH null colons and is concomitant with a doubling of prostaglandin E(2) in 15-PGDH null colonic mucosa. A parallel role for 15-PGDH loss in promoting the earliest steps of colon neoplasia in humans is supported by our finding of a universal loss of 15-PGDH expression in microscopic colon adenomas recovered from patients with familial adenomatous polyposis, including adenomas as small as a single crypt. These models thus delineate the in vivo significance of 15-PGDH-mediated negative regulation of the COX-2 pathway and moreover reveal the particular importance of 15-PGDH in opposing the neoplastic progression of colonic aberrant crypt foci.

Effects of Two Traditional Chinese Cooking Oils, Canola and Pork, on pH and Cholic Acid Content of Faeces and Colon Tumorigenesis in Kunming Mice.

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He, Xiao-Qiong; Duan, Jia-Li; Zhou, Jin; Song, Zhong-Yu; Cichello, Simon Angelo

2015-01-01

Faecal pH and cholate are two important factors that can affect colon tumorigenesis, and can be modified by diet. In this study, the effects of two Chinese traditional cooking oils (pork oil and canola/rapeseed oil) on the pH and the cholic acid content in feces, in addition to colon tumorigenesis, were studied in mice. Kunming mice were randomized into various groups; negative control group (NCG), azoxymethane control group (ACG), pork oil group (POG), and canola oil Ggroup (COG). Mice in the ACG were fed a basic rodent chow; mice in POG and COG were given 10% cooking oil rodent chow with the respective oil type. All mice were given four weekly AOM (azoxymethane) i.p. injections (10 mg/kg). The pH and cholic acid of the feces were examined every two weeks. Colon tumors, aberrant crypt foci and organ weights were examined 32 weeks following the final AOM injection. The results showed that canola oil significantly decreased faecal pH in female mice (P0.05). Pork oil significantly increased the feces pH in both male and female mice (Pcooking oil effects faecal pH, but does not affect the faecal cholic acid content and thus AOM-induced colon neoplastic ACF is modified by dietary fat.

Weight loss following diet-induced obesity does not alter colon tumorigenesis in the AOM mouse model.

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Velázquez, Kandy T; Enos, Reilly T; Carson, Meredith S; Cranford, Taryn L; Bader, Jackie E; Chatzistamou, Ioulia; Singh, Udai P; Nagarkatti, Prakash S; Nagarkatti, Mitzi; Davis, J Mark; Carson, James A; Murphy, E Angela

2016-10-01

Obesity presents a significant public health concern given its association with increased cancer incidence, unfavorable prognosis, and metastasis. However, there is very little literature on the effects of weight loss, following obesity, on risk for colon cancer or liver cancer. Therefore, we sought to study whether intentional weight loss through diet manipulation was capable of mitigating colon and liver cancer in mice. We fed mice with a high-fat diet (HFD) comprised of 47% carbohydrates, 40% fat, and 13% protein for 20 wk to mimic human obesity. Subsequently, azoxymethane (AOM) was used to promote colon and liver carcinogenesis. A subset of obese mice was then switched to a low-fat diet (LFD) containing 67.5% carbohydrate, 12.2% fat, and 20% protein to promote intentional weight loss. Body weight loss and excess fat reduction did not protect mice from colon cancer progression and liver dysplastic lesion in the AOM-chemical-cancer model even though these mice had improved blood glucose and leptin levels. Intentional weight loss in AOM-treated mice actually produced histological changes that resemble dysplastic alterations in the liver and presented a higher percentage of F4/80 + CD206 + macrophages and activated T cells (CD4 + CD69 + ) in the spleen and lymph nodes, respectively. In addition, the liver of AOM-treated mice exposed to a HFD during the entire period of the experiment exhibited a marked increase in proliferation and pNF-κB activation. Altogether, these data suggest that intentional weight loss following chemical-induced carcinogenesis does not affect colon tumorigenesis but may in fact negatively impact liver repair mechanisms. Copyright © 2016 the American Physiological Society.

[Changes of expression of miR-155 in colitis-associated colonic carcinogenesis].

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Li, Weiwei; Han, Wenxiao; Zhao, Xinhua; Wang, Hongying

2014-04-01

To investigate the changes of miR-155 and its target genes in colitis-associated carcinogenesis. Colitis-associated colon cancer was induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in C57BL/6 mice. Mice of three different stages during the development of colon cancer were obtained, named AD1, AD2 and AD3, respectively. A control group of mice without any treatment and a DSS only group representing chronic inflammation without cancer were set up as well. Colon tissue was collected and expression of miR-155 in the colon tissues was measured by real-time fluorescent quantitative PCR. TargetScan and PicTar were used to predict potential target genes of miR-155, which were then preliminarily screened with our gene expression microarray database of AOM-DSS mouse model. Regular PCR was used to confirm the changes of the expression of these potential target genes in AOM-DSS mouse model. Colitis-associated colon cancer was effectively induced by azoxymethane and dextran sulfate sodium in C57BL/6 mice. Histological examination revealed that the evolution process was sequentially from normal, mild dysplasia, moderate dysplasia, and severe dysplasia to adenocarcinoma in the AOM-DSS mouse model. The level of miR-155 was gradually elevated with the formation of colitis-associated colon cancer. There was no significant difference between the levels of miR-155 expression in the DSS group (0.005 6 ± 0.003 7) and control group (0.012 0 ± 0.005 1) (P > 0.05), but the level of miR-155 in the AD3 group (0.054 4 ± 0.027 0) was significantly higher than that of the DSS group (0.005 6 ± 0.003 7)(P Bcorl1, Cacna1c, Rspo2 and Foxo3 were potential target genes of miR-155 in the AOM-DSS mouse model. Changes of Kcna1 and Cacna1c in the AOM-DSS mouse model were validated to be consistent with the changes obtained with the gene expression microarray. The up-regulation of miR-155 is related to colitis-associated carcinogenesis, but is irrelevant to chronic inflammation in the

Gene expression profile and genomic alterations in colonic tumours induced by 1,2-dimethylhydrazine (DMH) in rats

International Nuclear Information System (INIS)

Femia, Angelo Pietro; Luceri, Cristina; Toti, Simona; Giannini, Augusto; Dolara, Piero; Caderni, Giovanna

2010-01-01

Azoxymethane (AOM) or 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis in rats shares many phenotypical similarities with human sporadic colon cancer and is a reliable model for identifying chemopreventive agents. Genetic mutations relevant to human colon cancer have been described in this model, but comprehensive gene expression and genomic analysis have not been reported so far. Therefore, we applied genome-wide technologies to study variations in gene expression and genomic alterations in DMH-induced colon cancer in F344 rats. For gene expression analysis, 9 tumours (TUM) and their paired normal mucosa (NM) were hybridized on 4 × 44K Whole rat arrays (Agilent) and selected genes were validated by semi-quantitative RT-PCR. Functional analysis on microarray data was performed by GenMAPP/MappFinder analysis. Array-comparative genomic hybridization (a-CGH) was performed on 10 paired TUM-NM samples hybridized on Rat genome arrays 2 × 105K (Agilent) and the results were analyzed by CGH Analytics (Agilent). Microarray gene expression analysis showed that Defcr4, Igfbp5, Mmp7, Nos2, S100A8 and S100A9 were among the most up-regulated genes in tumours (Fold Change (FC) compared with NM: 183, 48, 39, 38, 36 and 32, respectively), while Slc26a3, Mptx, Retlna and Muc2 were strongly down-regulated (FC: -500; -376, -167, -79, respectively). Functional analysis showed that pathways controlling cell cycle, protein synthesis, matrix metalloproteinases, TNFα/NFkB, and inflammatory responses were up-regulated in tumours, while Krebs cycle, the electron transport chain, and fatty acid beta oxidation were down-regulated. a-CGH analysis showed that four TUM out of ten had one or two chromosomal aberrations. Importantly, one sample showed a deletion on chromosome 18 including Apc. The results showed complex gene expression alterations in adenocarcinomas encompassing many altered pathways. While a-CGH analysis showed a low degree of genomic imbalance, it is interesting to

Fermented dairy products modulate Citrobacter rodentium-induced colonic hyperplasia.

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Collins, James W; Chervaux, Christian; Raymond, Benoit; Derrien, Muriel; Brazeilles, Rémi; Kosta, Artemis; Chambaud, Isabelle; Crepin, Valerie F; Frankel, Gad

2014-10-01

We evaluated the protective effects of fermented dairy products (FDPs) in an infection model, using the mouse pathogen Citrobacter rodentium (CR). Treatment of mice with FDP formulas A, B, and C or a control product did not affect CR colonization, organ specificity, or attaching and effacing lesion formation. Fermented dairy product A (FDP-A), but neither the supernatant from FDP-A nor β-irradiated (IR) FDP-A, caused a significant reduction in colonic crypt hyperplasia and CR-associated pathology. Profiling the gut microbiota revealed that IR-FDP-A promoted higher levels of phylotypes belonging to Alcaligenaceae and a decrease in Lachnospiraceae (Ruminococcus) during CR infection. Conversely, FDP-A prevented a decrease in Ruminococcus and increased Turicibacteraceae (Turicibacter). Importantly, loss of Ruminococcus and Turicibacter has been associated with susceptibility to dextran sodium sulfate-induced colitis. Our results demonstrate that viable bacteria in FDP-A reduced CR-induced colonic crypt hyperplasia and prevented the loss of key bacterial genera that may contribute to disease pathology. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

Chemoprevention of colon carcinogenesis by polyethylene glycol: suppression of epithelial proliferation via modulation of SNAIL/beta-catenin signaling.

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Roy, Hemant K; Kunte, Dhananjay P; Koetsier, Jennifer L; Hart, John; Kim, Young L; Liu, Yang; Bissonnette, Marc; Goldberg, Michael; Backman, Vadim; Wali, Ramesh K

2006-08-01

Polyethylene glycol (PEG) is one of the most potent chemopreventive agents against colorectal cancer; however, the mechanisms remain largely unexplored. In this study, we assessed the ability of PEG to target cyclin D1-beta-catenin-mediated hyperproliferation in the azoxymethane-treated rat model and the human colorectal cancer cell line, HT-29. Azoxymethane-treated rats were randomized to AIN-76A diet alone or supplemented with 5% PEG-8000. After 30 weeks, animals were euthanized and biopsies of aberrant crypt foci and uninvolved crypts were subjected to immunohistochemical and immunoblot analyses. PEG markedly suppressed both early and late markers of azoxymethane-induced colon carcinogenesis (fractal dimension by 80%, aberrant crypt foci by 64%, and tumors by 74%). In both azoxymethane-treated rats and HT-29 cells treated with 5% PEG-3350 for 24 hours, PEG decreased proliferation (45% and 52%, respectively) and cyclin D1 (78% and 56%, respectively). Because beta-catenin is the major regulator of cyclin D1 in colorectal cancer, we used the T-cell factor (Tcf)-TOPFLASH reporter assay to show that PEG markedly inhibited beta-catenin transcriptional activity. PEG did not alter total beta-catenin expression but rather its nuclear localization, leading us to assess E-cadherin expression (a major determinant of beta-catenin subcellular localization), which was increased by 73% and 71% in the azoxymethane-rat and HT-29 cells, respectively. We therefore investigated the effect of PEG treatment on levels of the negative regulator of E-cadherin, SNAIL, and observed a 50% and 75% decrease, respectively. In conclusion, we show, for the first time, a molecular mechanism through which PEG imparts its antiproliferative and hence profound chemopreventive effect.

Long-term organ culture of adult rat colon

DEFF Research Database (Denmark)

Shamsuddin, A.K.M.; Barrett, L.A.; Autrup, Herman

1978-01-01

. The effect of in vivo carcinogen pretreatment was also studied. The explant culture from control untreated animals showed good epithelial differentiation with crypts until 6 weeks. In contrast, the explants from animals pretreated with 4 weekly doses of azoxymethane consistently showed epithelial......Colon explants from adult rats were maintained in culture for over 3 months in our laboratories with good epithelial preservation and cellular differentiation. The light and transmission electron microscopic features of rat colon mucosa during the culture period are described. In all the explants...

[In vitro and in vivo effects of mango pulp (Mangifera indica cv. Azucar) in colon carcinogenesis].

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Corrales-Bernal, Andrea; Amparo Urango, Luz; Rojano, Benjamín; Maldonado, Maria Elena

2014-03-01

Mango pulp contains ascorbic acid, carotenoids, polyphenols, terpenoids and fiber which are healthy and could protect against colon cancer. The aim of this study was to evaluate the antiproliferative and preventive capacity of an aqueous extract of Mangifera indica cv. Azúcar on a human colon adenocarcinoma cell line (SW480) and in a rodent model of colorectal cancer, respectively. The content of total phenolics, flavonoids and carotenoids were also analyzed in the extract. SW480 cell growth was inhibited in a dose and time dependent manner by 22.3% after a 72h exposure to the extract (200 µg/ mL). Colon carcinogenesis was initiated in Balb/c mice by two intra-peritoneal injections of azoxymethane (AOM) at the third and fourth week of giving mango in drinking water (0.3%, 0.6%, 1.25%). After 10 weeks of treatment, in the colon of mice receiving 0.3% mango, aberrant crypt foci formation was inhibited more than 60% (p=0,05) and the inhibition was dose-dependent when compared with controls receiving water. These results show that mango pulp, a natural food, non toxic, part of human being diet, contains bioactive compounds able to reduce growth of tumor cells and to prevent the appearance of precancerous lesions in colon during carcinogenesis initiation.

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

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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

Induction of colonic aberrant crypts in mice by feeding apparent N-nitroso compounds derived from hot dogs

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Davis, Michael E; Lisowyj, Michal P; Zhou, Lin; Wisecarver, James L; Gulizia, James M; Shostrom, Valerie K; Naud, Nathalie; Corpet, Denis E; Mirvish, Sidney S

2012-01-01

Nitrite-preserved meats (e.g., hot dogs) may help cause colon cancer because they contain N-nitroso compounds. We tested whether purified hot-dog-derived total apparent N-nitroso compounds (ANC) could induce colonic aberrant crypts, which are putative precursors of colon cancer. We purified ANC precursors in hot dogs and nitrosated them to produce ANC. In preliminary tests, CF1 mice received 1 or 3 i.p. injections of 5mg azoxymethane (AOM)/kg. In Experiments 1 and 2, female A/J mice received ANC in diet. In Experiment 1, ANC dose initially dropped sharply because the ANC precursors had mostly decomposed but, later in Experiment 1 and throughout Experiment 2, ANC remained at 85 nmol/g diet. Mice were killed after 8 (AOM tests) or 17–34 (ANC tests) wk. Median numbers of aberrant crypts in the distal 2 cm of the colon for 1 and 3 AOM injections, CF1 controls, ANC (Experiment 1), ANC (Experiment 2),and untreated A/J mice were 31, 74, 12, 20, 12, and 5–6, with P ANC tests. Experiment 2 showed somewhat increased numbers of colonic mucin-depleted foci in the ANC-treated group. We conclude that hot-dog-derived ANC induced significant numbers of aberrant crypts in the mouse colon. PMID:22293095

Comparative study of 1,2-dimethylhydrazine and azoxymethane on the induction of colorectal cancer in rats

Directory of Open Access Journals (Sweden)

Mario Jorge Jucá

2014-07-01

Full Text Available The induced colorectal carcinogenesis in rodents has a long history and currently uses the substances 1,2-dimethylhydrazine and azoxymethane. Objective: The aim of this study was to compare the inductive effect of the substances azoxymethane and 1,2-dimethylhydrazine in colorectal carcinogenesis. Method: 30 randomly chosen male Wistar rats were divided into four groups. G1 group was treated with 1,2-dimethylhydrazine and C1 was its control group; G2 group was treated azoxymethane and C2 was its control group. The animals were weekly weighed until euthanasia, when their intestines were removed, processed and analyzed by an experienced pathologist. Results: Among the control groups (C1 and C2 no histologic changes were observed; moderate dysplasia was detected in G2 group; hyperplasia, mild dysplasia, severe dysplasia and carcinoma were observed in G1 group. When this study compared the cost of the substances, 1,2-dimethylhydrazine was more than 50 times less expensive than azoxymethane. Conclusion: Azoxymethane is able to promote histological changes consistent with colorectal carcinogenesis. 1,2-Dimethylhydrazine produced neoplasia and dysplasia, and, compared to the azoxymethane, was more efficient in the induction of colorectal cancer. Resumo: A carcinogênese colorretal induzida em roedores tem longa história e utiliza, atualmente, as substâncias 1,2 dimetil-hidrazina (DMH e azoximetano (AOM. Objetivo: Comparar o efeito indutivo das substâncias AOM e DMH para o câncer colorretal (CCR. Método: 30 ratos Wistar machos foram randomizados em quatro grupos. O grupo G1 foi inoculado com DMH, o grupo C1 foi seu controle; G2 recebeu o AOM e C2 foi seu controle. Os animais foram pesados semanalmente até a eutanásia, quando tiveram seus intestinos retirados, processados e analisados por um patologista experiente. Resultados: Os animais dos grupos de controle apresentaram tecido colorretal normal e os animais do grupo G2 apresentaram um padrão de

Brewers’ Rice: A By-Product from Rice Processing Provides Natural Hepatorenal Protection in Azoxymethane-Induced Oxidative Stress in Rats

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Bee Ling Tan

2015-01-01

Full Text Available Brewers’ rice, which is known locally as temukut, is a mixture of broken rice, rice bran, and rice germ. Our present study was designed to identify the effect of brewers’ rice on the attenuation of liver and kidney damage induced by azoxymethane (AOM. Alanine transaminase (ALT, alkaline phosphatase (ALP, aspartate transaminase (AST, creatinine, and urea were evaluated to understand potential hepatoprotective effects and the ability of brewers’ rice to attenuate kidney pathology induced by AOM treatment. Liver and kidney tissues were evaluated by hematoxylin and eosin (H&E staining. Overall analyses revealed that brewers’ rice improved the levels of serum markers in a manner associated with better histopathological outcomes, which indicated that brewers’ rice could enhance recovery from hepatocyte and kidney damage. Taken together, these results suggest that brewers’ rice could be used in future applications to combat liver and kidney disease.

Colon cancer chemoprevention by a novel NO chimera that shows anti-inflammatory and antiproliferative activity in vitro and in vivo.

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Hagos, Ghenet K; Carroll, Robert E; Kouznetsova, Tatiana; Li, Qian; Toader, Violeta; Fernandez, Patricia A; Swanson, Steven M; Thatcher, Gregory R J

2007-08-01

Chemopreventive agents in colorectal cancer possess either antiproliferative or anti-inflammatory actions. Nonsteroidal anti-inflammatory drugs (NSAID) and cyclooxygenase-2 inhibitors have shown promise, but are compromised by side effects. Nitric oxide donor NSAIDs are organic nitrates conjugated via a labile linker to an NSAID, originally designed for use in pain relief, that have shown efficacy in colorectal cancer chemoprevention. The NO chimera, GT-094, is a novel nitrate containing an NSAID and disulfide pharmacophores, a lead compound for the design of agents specifically for colorectal cancer. GT-094 is the first nitrate reported to reduce aberrant crypt foci (by 45%) when administered after carcinogen in the standard azoxymethane rat model of colorectal cancer. Analysis of proximal and distal colon tissue from 8- and 28-week rat/azoxymethane studies showed that GT-094 treatment reduced colon crypt proliferation by 30% to 69%, reduced inducible NO synthase (iNOS) levels by 33% to 67%, reduced poly(ADP-ribose)polymerase-1 expression and cleavage 2- to 4-fold, and elevated levels of p27 in the distal colon 3-fold. Studies in cancer cell cultures recapitulated actions of GT-094: antiproliferative activity and transient G(2)-M phase cell cycle block were measured in Caco-2 cells; apoptotic activity was examined but not observed; anti-inflammatory activity was seen in the inhibition of up-regulation of iNOS and endogenous NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells. In summary, antiproliferative, anti-inflammatory, and cytoprotective activity observed in vivo and in vitro support GT-094 as a lead compound for the design of NO chimeras for colorectal cancer chemoprevention.

PGE2-induced colon cancer growth is mediated by mTORC1

International Nuclear Information System (INIS)

Dufour, Marc; Faes, Seraina; Dormond-Meuwly, Anne; Demartines, Nicolas; Dormond, Olivier

2014-01-01

Highlights: • PGE 2 activates mTORC1 in colon cancer cells. • Inhibition of mTORC1 blocks PGE 2 induced colon cancer cell growth. • mTORC1 is a signaling intermediary in PGE 2 induced colon cancer cell responses. - Abstract: The inflammatory prostaglandin E 2 (PGE 2 ) cytokine plays a key role in the development of colon cancer. Several studies have shown that PGE 2 directly induces the growth of colon cancer cells and furthermore promotes tumor angiogenesis by increasing the production of the vascular endothelial growth factor (VEGF). The signaling intermediaries implicated in these processes have however not been fully characterized. In this report, we show that the mechanistic target of rapamycin complex 1 (mTORC1) plays an important role in PGE 2 -induced colon cancer cell responses. Indeed, stimulation of LS174T cells with PGE 2 increased mTORC1 activity as observed by the augmentation of S6 ribosomal protein phosphorylation, a downstream effector of mTORC1. The PGE 2 EP 4 receptor was responsible for transducing the signal to mTORC1. Moreover, PGE 2 increased colon cancer cell proliferation as well as the growth of colon cancer cell colonies grown in matrigel and blocking mTORC1 by rapamycin or ATP-competitive inhibitors of mTOR abrogated these effects. Similarly, the inhibition of mTORC1 by downregulation of its component raptor using RNA interference blocked PGE 2 -induced LS174T cell growth. Finally, stimulation of LS174T cells with PGE 2 increased VEGF production which was also prevented by mTORC1 inhibition. Taken together, these results show that mTORC1 is an important signaling intermediary in PGE 2 mediated colon cancer cell growth and VEGF production. They further support a role for mTORC1 in inflammation induced tumor growth

The effects of a "low-risk" diet on cell proliferation and enzymatic parameters of preneoplastic rat colon.

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Goettler, D; Rao, A V; Bird, R P

1987-01-01

The relationship between various dietary constituents and colon cancer has been demonstrated by previous research. This study was conducted to investigate the combined effects of several dietary constituents on the preneoplastic stage of azoxymethane (AOM)-induced colon cancer in rats. A nutritionally adequate, "low-risk" (LR) diet was formulated through the modulation of dietary fat, fiber, protein, vitamins A and E, and selenium. Female F344 rats were given three weekly subcutaneous injections of AOM and were maintained on either the LR diet or a "high-risk" (HR) diet. After 12 weeks, the rats were killed and the following parameters were determined: pH of colon contents, fecal beta-glucuronidase activity, tissue ornithine decarboxylase (ODC) activity, and colonic labeling index. The pH of the colon contents and incremental labeling index were lower in the group given the LR diet and treated with AOM compared with the group given the HR diet and treated with AOM; however, no statistically significant dietary effects were observed for beta-glucuronidase and ODC activities. The results of this study indicated that the colons of rats fed the LR diet exhibited different proliferative characteristics than did the colons of rats fed the HR diet.

Diet, genes, and microbes: complexities of colon cancer prevention.

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Birt, Diane F; Phillips, Gregory J

2014-01-01

Colorectal cancer is one of the leading causes of cancer-related deaths in the United States, and generally, as countries climb the economic ladder, their rates of colon cancer increase. Colon cancer was an early disease where key genetic mutations were identified as important in disease progression, and there is considerable interest in determining whether specific mutations sensitize the colon to cancer prevention strategies. Epidemiological studies have revealed that fiber- and vegetable-rich diets and physical activity are associated with reduced rates of colon cancer, while consumption of red and processed meat, or alcoholic beverages, and overconsumption as reflected in obesity are associated with increased rates. Animal studies have probed these effects and suggested directions for further refinement of diet in colon cancer prevention. Recently a central role for the microorganisms in the gastrointestinal tract in colon cancer development is being probed, and it is hypothesized that the microbes may integrate diet and host genetics in the etiology of the disease. This review provides background on dietary, genetic, and microbial impacts on colon cancer and describes an ongoing project using rodent models to assess the ability of digestion-resistant starch in the integration of these factors with the goal of furthering colon cancer prevention.

Dietary aloe vera gel powder and extract inhibit azoxymethane- induced colorectal aberrant crypt foci in mice fed a high- fat diet.

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Chihara, Takeshi; Shimpo, Kan; Kaneko, Takaaki; Beppu, Hidehiko; Higashiguchi, Takashi; Sonoda, Shigeru; Tanaka, Miyuki; Yamada, Muneo; Abe, Fumiaki

2015-01-01

Aloe vera gel exhibits protective effects against insulin resistance as well as lipid-lowering and anti-diabetic effects. The anti-diabetic compounds in this gel were identified as Aloe-sterols. Aloe vera gel extract (AVGE) containing Aloe-sterols has recently been produced using a new procedure. We previously reported that AVGE reduced large-sized intestinal polyps in Apc-deficient Min mice fed a high fat diet (HFD), suggesting that Aloe vera gel may protect against colorectal cancer. In the present study, we examined the effects of Aloe vera gel powder (AVGP) and AVGE on azoxymethane-induced colorectal preneoplastic aberrant crypt foci (ACF) in mice fed a HFD. Male C57BL/6J mice were given a normal diet (ND), HFD, HFD containing 0.5% carboxymethyl cellulose solution, which was used as a solvent for AVGE (HFDC), HFD containing 3% or 1% AVGP, and HFDC containing 0.0125% (H-) or 0.00375% (L-) AVGE. The number of ACF was significantly lower in mice given 3% AVGP and H-AVGE than in those given HFD or HFDC alone. Moreover, 3% AVGP, H-AVGE and L-AVGE significantly decreased the mean Ki-67 labeling index, assessed as a measure of cell proliferation in the colonic mucosa. In addition, hepatic phase II enzyme glutathione S-transferase mRNA levels were higher in the H-AVGE group than in the HFDC group. These results suggest that both AVGP and AVGE may have chemopreventive effects on colorectal carcinogenesis under the HFD condition. Furthermore, the concentration of Aloe-sterols was similar between 3% AVGP and H-AVGE, suggesting that Aloe-sterols were the main active ingredients in this experiment.

PGE{sub 2}-induced colon cancer growth is mediated by mTORC1

Energy Technology Data Exchange (ETDEWEB)

Dufour, Marc, E-mail: Marc.dufour@chuv.ch; Faes, Seraina, E-mail: Seraina.faes@chuv.ch; Dormond-Meuwly, Anne, E-mail: Anne.meuwly-Dormond@chuv.ch; Demartines, Nicolas, E-mail: Demartines@chuv.ch; Dormond, Olivier, E-mail: Olivier.dormond@chuv.ch

2014-09-05

Highlights: • PGE{sub 2} activates mTORC1 in colon cancer cells. • Inhibition of mTORC1 blocks PGE{sub 2} induced colon cancer cell growth. • mTORC1 is a signaling intermediary in PGE{sub 2} induced colon cancer cell responses. - Abstract: The inflammatory prostaglandin E{sub 2} (PGE{sub 2}) cytokine plays a key role in the development of colon cancer. Several studies have shown that PGE{sub 2} directly induces the growth of colon cancer cells and furthermore promotes tumor angiogenesis by increasing the production of the vascular endothelial growth factor (VEGF). The signaling intermediaries implicated in these processes have however not been fully characterized. In this report, we show that the mechanistic target of rapamycin complex 1 (mTORC1) plays an important role in PGE{sub 2}-induced colon cancer cell responses. Indeed, stimulation of LS174T cells with PGE{sub 2} increased mTORC1 activity as observed by the augmentation of S6 ribosomal protein phosphorylation, a downstream effector of mTORC1. The PGE{sub 2} EP{sub 4} receptor was responsible for transducing the signal to mTORC1. Moreover, PGE{sub 2} increased colon cancer cell proliferation as well as the growth of colon cancer cell colonies grown in matrigel and blocking mTORC1 by rapamycin or ATP-competitive inhibitors of mTOR abrogated these effects. Similarly, the inhibition of mTORC1 by downregulation of its component raptor using RNA interference blocked PGE{sub 2}-induced LS174T cell growth. Finally, stimulation of LS174T cells with PGE{sub 2} increased VEGF production which was also prevented by mTORC1 inhibition. Taken together, these results show that mTORC1 is an important signaling intermediary in PGE{sub 2} mediated colon cancer cell growth and VEGF production. They further support a role for mTORC1 in inflammation induced tumor growth.

Chemopreventive effects of PBI-Se, a selenium-containing analog of PBIT, on AOM-induced aberrant crypt foci in F344 rats.

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Janakiram, Naveena B; Mohammed, Altaf; Ravillah, Durgadevi; Choi, Chang In; Zhang, Yuting; Desai, Dhimant; Amin, Shantu; Rao, Chinthalapally V

2013-08-01

Inducible nitric oxide synthase (iNOS) is a potential target for the treatment of inflammation and cancer. Previously, we showed that the selective iNOS inhibitor S,S'-1,4-phenylenebis(1,2-ethanediyl)bis-isothiourea (PBIT) caused significant inhibition of colon carcinogenesis induced by azoxymethane (AOM), although it did not completely abrogate NO production due to the exogenous bioavailability of NO and NO generation by eNOS in tumor tissues. To create an iNOS-targeting molecule that may have additional benefits, a novel isosteric analog of PBIT, PBI-Se, was developed, in which sulfur was replaced with selenium. Chemopreventive efficacy of PBI-Se was evaluated in an AOM-induced rat colon carcinogenesis model using aberrant crypt foci (ACF) as the endpoint. At 7 weeks of age, rats (12/group) were fed the control diet (AIN 76A) and then colonic ACF were induced with two AOM treatments. Three days later, rats were fed diets containing PBI-Se (0-20 ppm) for 8 weeks, and then ACF were evaluated histopathologically. Dietary administration of 10 or 20 ppm of PBI-Se significantly suppressed AOM-induced total colonic ACF formation (32 or 41%, pPBI-Se was dose-dependent and was half the dose of PBIT for inhibiting total ACF in rats. Both PBIT and PBI-Se induced dose-dependent apoptosis in CaCo2 cells and caused a significant decrease in the cell cycle proteins cyclin D1 (70%, pPBI-Se (2 and 4  µM) significantly decreased the LPS-induced cytokine interleukin-6 level. Incorporation of selenium into the structure of PBIT provided the agent with additional novel cytotoxic and immunologic properties. Results from the in vitro and in vivo bioassays suggest that PBI-Se could be developed further for the prevention and treatment of colon cancer.

[6]-Gingerol induces caspase-dependent apoptosis and prevents PMA-induced proliferation in colon cancer cells by inhibiting MAPK/AP-1 signaling.

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E K Radhakrishnan

Full Text Available We report mechanism-based evidence for the anticancer and chemopreventive efficacy of [6]-gingerol, the major active principle of the medicinal plant, Ginger (Zingiber officinale, in colon cancer cells. The compound was evaluated in two human colon cancer cell lines for its cytotoxic effect and the most sensitive cell line, SW-480, was selected for the mechanistic evaluation of its anticancer and chemopreventive efficacy. The non-toxic nature of [6]-gingerol was confirmed by viability assays on rapidly dividing normal mouse colon cells. [6]-gingerol inhibited cell proliferation and induced apoptosis as evidenced by externalization of phosphatidyl serine in SW-480, while the normal colon cells were unaffected. Sensitivity to [6]-gingerol in SW-480 cells was associated with activation of caspases 8, 9, 3 &7 and cleavage of PARP, which attests induction of apoptotic cell death. Mechanistically, [6]-gingerol down-regulated Phorbol Myristate Acetate (PMA induced phosphorylation of ERK1/2 and JNK MAP kinases and activation of AP-1 transcription factor, but had only little effects on phosphorylation of p38 MAP kinase and activation of NF-kappa B. Additionally, it complemented the inhibitors of either ERK1/2 or JNK MAP kinase in bringing down the PMA-induced cell proliferation in SW-480 cells. We report the inhibition of ERK1/2/JNK/AP-1 pathway as a possible mechanism behind the anticancer as well as chemopreventive efficacy of [6]-gingerol against colon cancer.

Local oral immunization with synthetic peptides induces a dual mucosal IgG and salivary IgA antibody response and prevents colonization of Streptococcus mutans.

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Lehner, T; Haron, J; Bergmeier, L A; Mehlert, A; Beard, R; Dodd, M; Mielnik, B; Moore, S

1989-01-01

A small cell surface antigen of Streptococcus mutans was partially sequenced and the amino terminal peptides of 11, 15 and 20 amino acid residues and a dimer of the 15 and 20 residues peptides were synthesized. The synthetic peptides (SP) were used in topical oral immunization of the gingivomucosal epithelium of macaque monkeys. Sequential examination for antibodies over a period of up to 30 weeks revealed that six applications of the linear or cyclized SP11 and a random SP11 induced negligible or very low antibody levels. In contrast, the SP17 (SP15 with added cysteine at each terminus), SP21 (SP20 with one cysteine) and the dimer (SP35) induced significant anti-SP as well as anti-native streptococcal antibodies in the gingival fluid and in saliva. The functional significance of this immune response was examined by studying its effect on oral colonization of S. mutans following feeding of a carbohydrate-rich diet. Whereas control animals, sham-immunized with a random SP of 11 residues, showed increased colonization of the teeth by S. mutans, there was no colonization or a significant reduction in colonization of animals immunized with the cyclized SP17, linear SP21 or dimerized SP35. These experiments suggest that local immunization with SP derived from the sequences of a streptococcal cell surface antigen induce a dual local immune response of gingival IgG and salivary IgA antibodies against the SP and native SA. These antibodies may be involved in preventing colonization of S. mutans, which is the principal agent in the development of dental caries. PMID:2759661

Conjugated linoleic acid ameliorates inflammation-induced colorectal cancer in mice through activation of PPARgamma.

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Evans, Nicholas P; Misyak, Sarah A; Schmelz, Eva M; Guri, Amir J; Hontecillas, Raquel; Bassaganya-Riera, Josep

2010-03-01

Conjugated linoleic acid (CLA) exerts a protective effect on experimental inflammatory bowel disease and shows promise as a chemopreventive agent against colorectal cancer (CRC) in mice, although the mechanisms by which it exerts its beneficial effects against malignancies in the gut are not completely understood. Mice lacking PPARgamma in immune and epithelial cells and PPARgamma-expressing littermates were fed either control or CLA-supplemented (1 g CLA/100 g) diets to determine the role of PPARgamma in inflammation-induced CRC. To induce tumor formation and colitis, mice were treated with azoxymethane and then challenged with 2% dextran sodium sulfate, respectively. Dietary CLA ameliorated disease activity, decreased colitis, and prevented adenocarcinoma formation in the PPARgamma-expressing floxed mice but not in the tissue-specific PPARgamma-null mice. Dietary CLA supplementation significantly decreased the percentages of macrophages in the mesenteric lymph nodes (MLN) regardless of the genotype and increased regulatory T cell numbers in MLN of PPARgamma-expressing, but not in the tissue-specific, PPARgamma-null mice. Colonic tumor necrosis factor-alpha mRNA expression was significantly suppressed in CLA-fed, PPARgamma-expressing mice. This study suggests CLA ameliorates colitis and prevents tumor formation in part through a PPARgamma-dependent mechanism.

E-cadherin Mediates the Preventive Effect of Vitamin D3 in Colitis-associated Carcinogenesis.

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Xin, Yu; He, Longmei; Luan, Zijian; Lv, Hong; Yang, Hong; Zhou, Ying; Zhao, Xinhua; Zhou, Weixun; Yu, Songlin; Tan, Bei; Wang, Hongying; Qian, Jiaming

2017-09-01

Vitamin D3 is beneficial in ameliorating or preventing inflammation and carcinogenesis. Here, we evaluated if vitamin D3 has a preventive effect on colitis-associated carcinogenesis. Administration of azoxymethane (AOM), followed with dextran sulfate sodium (DSS), was used to simulate colitis-associated colon cancer in mice. The supplement of vitamin D3 at different dosages (15, 30, 60 IU·g·w), started before AOM or immediately after DSS treatment (post 60), was sustained to the end of the experiment. Dietary vitamin D3 significantly reduced the number of tumors and tumor burden in a dose-dependent manner. Of note, vitamin D3 in high doses showed significant preventive effects on carcinogenesis regardless of administration before or after AOM-DSS treatment. Cell proliferation decreased in vitamin D3 groups compared with the control group after inhibition of expression of β-catenin and its downstream target gene cyclin D1 in the colon. In vitro, vitamin D3 reduced the transcriptional activity and nuclear level of β-catenin, and it also increased E-cadherin expression and its binding affinity for β-catenin. Moreover, repression of E-cadherin was rescued by supplemental vitamin D3 in mouse colons. Taken together, our results indicate that vitamin D3 effectively suppressed colonic carcinogenesis in the AOM-DSS mouse model. Our findings further suggest that upregulation of E-cadherin contributes to the preventive effect of vitamin D3 on β-catenin activity.

Dietary Factors Modulate Colonic Tumorigenesis Through the Interaction of Gut Microbiota and Host Chloride Channels.

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Zhang, Yong; Kang, Chao; Wang, Xiao-Lan; Zhou, Min; Chen, Meng-Ting; Zhu, Xiao-Hui; Liu, Kai; Wang, Bin; Zhang, Qian-Yong; Zhu, Jun-Dong; Mi, Man-Tian

2018-03-01

In recent decades, the association among diet, gut microbiota, and the risk of colorectal cancer (CRC) has been established. Gut microbiota and associated metabolites, such as bile acids and butyrate, are now known to play a key role in CRC development. The aim of this study is to identify that the progression to CRC is influenced by cholic acid, sodium butyrate, a high-fat diet, or different dose of dihydromyricetin (DMY) interacted with gut microbiota. An AOM/DSS (azoxymethan/dextran sodium sulfate) model is established to study the gut microbiota compsition before and after tumor formation during colitis-induced tumorigenesis. All above dietary factors profoundly influence the composition of gut microbiota and host colonic tumorigenesis. In addition, mice with DMY-modified initial microbiota display different degrees of chemically induced tumorigenesis. Mechanism analysis reveals that gut microbiota-associated chloride channels participated in colon tumorigenesis. Gut microbiota changes occur in the hyperproliferative stage before tumor formation. Gut microbiota and host chloride channels, both of which are regulated by dietary factors, are associated with CRC development. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

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LENUS (Irish Health Repository)

Yan, Min

2009-06-09

Pharmacologic inhibitors of the prostaglandin-synthesizing COX-2 oncogene prevent the development of premalignant human colon adenomas. However, resistance to treatment is common. In this study, we show that the adenoma prevention activity of the COX-2 inhibitor celecoxib requires the concomitant presence of the 15-hydroxyprostaglandin dehydrogenase (15-PGDH) tumor suppressor gene, and that loss of 15-PGDH expression imparts resistance to celecoxib\\'s anti-tumor effects. We first demonstrate that the adenoma-preventive activity of celecoxib is abrogated in mice genetically lacking 15-PGDH. In FVB mice, celecoxib prevents 85% of azoxymethane-induced tumors >1 mm in size, but is essentially inactive in preventing tumor induction in 15-PGDH-null animals. Indeed, celecoxib treated 15-PGDH null animals develop more tumors than do celecoxib naive WT mice. In parallel with the loss of tumor prevention activity, celecoxib-mediated suppression of colonic PGE(2) levels is also markedly attenuated in 15-PGDH-null versus WT mice. Finally, as predicted by the murine models, humans with low colonic 15-PGDH levels also exhibit celecoxib resistance. Specifically, in a colon adenoma prevention trial, in all cases tested, individuals who developed new adenomas while receiving celecoxib treatment were also found as having low colonic 15-PGDH levels.

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

[Evaluation of knowledge about colon cancer prevention versus other tumors].

Science.gov (United States)

Sanguinetti, José María; Henry, Nicolás; Ocaña, Domingo; Polesel, Julio Lotero

2015-06-01

In Argentina almost 7% of deaths are due to different cancers with screening strategies. Evaluate knowledge about cancer prevention compared with other tumors. Materials. A descriptive and comparative study. A survey between April and June 2013 in Salta City, province of Salta, Argentina. Correct answers were considered. Statistical analysis: Descriptive (mean and percentage), comparative Chi square Test (significance level Pmama and cervix. 20% (CI 0,13-0,28) knew that colon cancer has a genetic predisposition and 58% (CI 0,48-0,67) about mama. 73% (CI 0,63-0,8) received information about cancer prevention. The main source of information was the physician. 46% (CI 0,36-0,55) received medical care in private institutions. Those who had social security, higher educational levels and medical care in private institutions had better knowledge about cancer prevention except in colon cancer. The global results showed levels below 70% in general but extremely low in colon cancer. Not having social security, receiving medical care in public institutions and having a low educational level are related with poor knowledge about cancer prevention except for colon and prostate cancer.

Lactulose mediates suppression of dextran sodium sulfate-induced colon inflammation by increasing hydrogen production.

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Chen, Xiao; Zhai, Xiao; Shi, Jiazi; Liu, Wen Wu; Tao, Hengyi; Sun, Xuejun; Kang, Zhimin

2013-06-01

Molecular hydrogen (H2) is a potent antioxidant and able to protect organs from oxidative stress injuries. Orally administered lactulose, a potent H2 inducer, is digested by colon microflora and significantly increases H2 production, indicating its potential anti-inflammatory action. To evaluate the anti-inflammatory effects of lactulose on dextran sodium sulfate (DSS)-induced colitis in mice. Mice were randomly assigned into seven groups, receiving regular distilled water, H2-rich saline (peritoneal injection), DSS, oral lactulose (0.1, 0.15, 0.2 ml/10 g, respectively), and lactulose (0.2 ml/10 g) + oral antibiotics. The mouse model of human ulcerative colitis was established by supplying mice with water containing DSS. The H2 breath test was used to determine the exhaled H2 concentration. Body weight, colitis score, colon length, pathological features and tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), maleic dialdehyde (MDA) and marrow peroxidase (MPO) levels in colon lesions were evaluated. After 7 days, DSS-induced loss of body weight, increase of colitis score, shortening of colon length, pathological changes and elevated levels of TNF-α, IL-1β, MDA, and MPO in colon lesions, were significantly suppressed by oral lactulose administration and intraperitoneally injected H2-rich saline. Ingestion of antibiotics significantly compromised the anti-inflammatory effects of lactulose. The H2 breath test showed that lactulose administration significantly induced hydrogen production and that antibiotics administration could inhibit H2 production. Lactulose can prevent the development of DSS-induced colitis and alleviate oxidative stress in the colon, as measured by MDA and MPO, probably by increasing endogenous H2 production.

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

NARCIS (Netherlands)

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

2016-01-01

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

The Potential Use of N-Myristoyltransferase as a Biomarker in the Early Diagnosis of Colon Cancer

International Nuclear Information System (INIS)

Kumar, Sujeet; Dimmock, Jonathan R; Sharma, Rajendra K

2011-01-01

Colon cancer is one of the most common malignant diseases and a major cause of mortality in the Western world. Metastasis to lymph nodes and other gastrointestinal organs, especially to the liver and lungs, is most common and occurs in up to 25% of cancer patients when initially diagnosed. The majority of colon cancers develop from noncancerous adenomatous polyps on the lining of the colon which grow over the years to become cancerous. If detected early, the surgical resections of the growth, often in combination with chemotherapy, significantly increases life expectancy. We have shown that the enzyme N-myristoyltransferase (NMT) which carries out lipid modification of several proteins (including many of those involved in oncogenesis) is expressed at higher levels in cancerous tissues from the colon. We have also shown that in peripheral blood mononuclear cells (PBMC) and bone marrow (BM) cells collected from colon cancer patients and from azoxymethane-induced rats the expression and localization of NMT is altered. We have observed strong positivity for NMT in immunohistochemical analysis for PBMC from colon cancer patients as compared to control groups. Furthermore, in the bone marrow (BM) mononuclear cells, NMT was found to be confined to the nuclei whereas in control groups it was observed to be located in the cytoplasm. In conclusion, this strikingly differential localization offers the basis of a potential investigational tool for screening or diagnosis of individuals at risk for or suspected of having colon cancer

Protein expression analysis of inflammation-related colon carcinogenesis

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Yasui Yumiko

2009-01-01

Full Text Available Background: Chronic inflammation is a risk factor for colorectal cancer (CRC development. The aim of this study was to determine the differences in protein expression between CRC and the surrounding nontumorous colonic tissues in the mice that received azoxymethane (AOM and dextran sodium sulfate (DSS using a proteomic analysis. Materials and Methods: Male ICR mice were given a single intraperitoneal injection of AOM (10 mg/kg body weight, followed by 2% (w/v DSS in their drinking water for seven days, starting one week after the AOM injection. Colonic adenocarcinoma developed after 20 weeks and a proteomics analysis based on two-dimensional gel electrophoresis and ultraflex TOF/TOF mass spectrometry was conducted in the cancerous and nontumorous tissue specimens. Results: The proteomic analysis revealed 21 differentially expressed proteins in the cancerous tissues in comparison to the nontumorous tissues. There were five markedly increased proteins (beta-tropomyosin, tropomyosin 1 alpha isoform b, S100 calcium binding protein A9, and an unknown protein and 16 markedly decreased proteins (Car1 proteins, selenium-binding protein 1, HMG-CoA synthase, thioredoxin 1, 1 Cys peroxiredoxin protein 2, Fcgbp protein, Cytochrome c oxidase, subunit Va, ETHE1 protein, and 7 unknown proteins. Conclusions: There were 21 differentially expressed proteins in the cancerous tissues of the mice that received AOM and DSS. Their functions include metabolism, the antioxidant system, oxidative stress, mucin production, and inflammation. These findings may provide new insights into the mechanisms of inflammation-related colon carcinogenesis and the establishment of novel therapies and preventative strategies to treat carcinogenesis in the inflamed colon.

Circumvention and reactivation of the p53 oncogene checkpoint in mouse colon tumors.

Science.gov (United States)

Aizu, Wataru; Belinsky, Glenn S; Flynn, Christopher; Noonan, Emily J; Boes, Colleen C; Godman, Cassandra A; Doshi, Bindi; Nambiar, Prashant R; Rosenberg, Daniel W; Giardina, Charles

2006-10-16

The p53 tumor suppressor protein is sequence-normal in azoxymethane (AOM)-induced mouse colon tumors, making them a good model for human colon cancers that retain a wild type p53 gene. Cellular localization and co-immunoprecipitation experiments using a cell line derived from an AOM-induced colon tumor (AJ02-NM(0) cells) pointed to constitutively expressed Mdm2 as being an important negative regulator of p53 in these cells. Although the Mdm2 inhibitory protein p19/ARF was expressed in AJ02-NM(0) cells, its level of expression was not sufficient for p53 activation. We tested the response of AJ02-NM(0) cells to the recently developed Mdm2 inhibitor, Nutlin-3. Nutlin-3 was found to activate p53 DNA binding in AJ02-NM(0) cells, to a level comparable to doxorubicin and 5-fluorouracil (5-FU). In addition, Nutlin-3 increased expression of the p53 target genes Bax and PERP to a greater extent than doxorubicin or 5-FU, and triggered a G2/M phase arrest in these cells, compared to a G1 arrest triggered by doxorubicin and 5-FU. The differences in the cellular response may be related to differences in the kinetics of p53 activation and/or its post-translational modification status. In an ex vivo experiment, Nutlin-3 was found to activate p53 target gene expression and apoptosis in AOM-induced tumor tissue, but not in normal adjacent mucosa. Our data indicate that Mdm2 inhibitors may be an effective means of selectively targeting colon cancers that retain a sequence-normal p53 gene while sparing normal tissue and that the AOM model is an appropriate model for the preclinical development of these drugs.

Role of phytochemicals in colon cancer prevention. A nutrigenomics approach

NARCIS (Netherlands)

Erk, van M.J.

2004-01-01

Specific food compounds, especially from fruits and vegetables, may protect against development of colon cancer. In this thesis effects and mechanisms of various phytochemicals in relation to colon cancer prevention were studied through application of large-scale gene expression profiling.

Inhibition of autophagy exerts anti-colon cancer effects via apoptosis induced by p53 activation and ER stress

International Nuclear Information System (INIS)

Sakitani, Kosuke; Hirata, Yoshihiro; Hikiba, Yohko; Hayakawa, Yoku; Ihara, Sozaburo; Suzuki, Hirobumi; Suzuki, Nobumi; Serizawa, Takako; Kinoshita, Hiroto; Sakamoto, Kei; Nakagawa, Hayato; Tateishi, Keisuke; Maeda, Shin; Ikenoue, Tsuneo; Kawazu, Shoji; Koike, Kazuhiko

2015-01-01

Although some molecularly targeted drugs for colorectal cancer are used clinically and contribute to a better prognosis, the current median survival of advanced colorectal cancer patients is not sufficient. Autophagy, a basic cell survival mechanism mediated by recycling of cellular amino acids, plays an important role in cancer. Recently, autophagy has been highlighted as a promising new molecular target. The unfolded protein response (UPR) reportedly act in complementary fashion with autophagy in intestinal homeostasis. However, the roles of UPR in colon cancer under autophagic inhibition remain to be elucidated. We aim to clarify the inhibitory effect of autophagy on colon cancer. We crossed K19 CreERT and Atg5 flox/flox mice to generate Atg5 flox/flox /K19 CreERT mice. Atg5 flox/flox /K19 CreERT mice were first treated with azoxymethane/dextran sodium sulfate and then injected with tamoxifen to inhibit autophagy in CK19-positive epithelial cells. To examine the anti-cancer mechanisms of autophagic inhibition, we used colon cancer cell lines harboring different p53 gene statuses, as well as small interfering RNAs (siRNAs) targeting Atg5 and immunoglobulin heavy-chain binding protein (BiP), a chaperone to aid folding of unfolded proteins. Colon tumors in Atg5 flox/flox /K19 CreERT mice showed loss of autophagic activity and decreased tumor size (the total tumor diameter was 28.1 mm in the control and 20.7 mm in Atg5 flox/flox /K19 CreERT mice, p = 0.036). We found that p53 and UPR/endoplasmic reticulum (ER) stress-related proteins, such as cleaved caspase 3, and CAAT/enhancer-binding protein homologous protein, are up-regulated in colon tumors of Atg5 flox/flox /K19 CreERT mice. Although Atg5 and BiP silencing, respectively, increased apoptosis in p53 wild type cells, Atg5 silencing alone did not show the same effect on apoptosis in p53 mutant cells. However, co-transfection of Atg5 and BiP siRNAs led to increased apoptosis in p53 mutant cells. Blocking autophagy

Chemopreventive Effect of Aster glehni on Inflammation-Induced Colorectal Carcinogenesis in Mice

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Kyung-Sook Chung

2018-02-01

Full Text Available Although Aster glehni is a common dietary herb that has various bioactivities, including anti-diabetic, anti-adipogenic, and anti-inflammatory effects, A. glehni has not been studied in colon cancer. Therefore, we hypothesized the chemopreventive effects of an ethanol extract of A. glehni (AG on azoxymethane/dextran sulfate sodium (AOM/DSS-induced colitis-associated cancer (CAC in mice. In this study, we found that treatment with AG significantly attenuated the AOM/DSS-induced enlargement of the spleen and shortening of the colon. In addition, colonic tumor formation, colonic damage, and increased muscle thickness were significantly reduced in AOM/DSS-induced mice fed AG. Treatment with AG also reduced intestinal interleukin (IL-1β, IL-6, and tumor necrosis factor (TNF-α production and decreased inducible nitric oxide synthase (iNOS and cyclooxygenase (COX-2 protein expression in mice with AOM/DSS-induced CAC. Furthermore, AG reduced nuclear factor (NF-κB activation via phosphorylation and degradation of inhibitor of kappa Bα (IκBα, leading to inhibition of NF-κB p65 nuclear translocation. It also downregulated the expression of NF-κB-related proteins, including the B-cell lymphoma 2 (Bcl-2 family and inhibitors of apoptosis proteins (IAPs, in mice with AOM/DSS-induced CAC. Taken together, these findings suggest that the treatment with AG inhibited colitis-associated colon carcinogenesis in mice, and this chemopreventive effect was strongly mediated by suppression of the NF-κB signaling pathway, indicating that AG could be a promising protective agent against CAC.

Dietary compounds that induce cancer preventive phase 2 enzymes activate apoptosis at comparable doses in HT29 colon carcinoma cells.

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Kirlin, W G; Cai, J; DeLong, M J; Patten, E J; Jones, D P

1999-10-01

Dietary agents that induce glutathione S-transferases and related detoxification systems (Phase 2 enzyme inducers) are thought to prevent cancer by enhancing elimination of chemical carcinogens. The present study shows that compounds of this group (benzyl isothiocyanate, allyl sulfide, dimethyl fumarate, butylated hydroxyanisole) activated apoptosis in human colon carcinoma (HT29) cells in culture over the same concentration ranges that elicited increases in enzyme activity (5-25, 25-100, 10-100, 15-60 micromol/L, respectively). Pretreatment of cells with sodium butyrate, an agent that induces HT29 cell differentiation, resulted in parallel increases in Phase 2 enzyme activities and induction of apoptosis in response to the inducers. Cell death characteristics included apoptotic morphological changes, appearance of cells at sub-G1 phase on flow cytometry, caspase activation, DNA fragmentation and TUNEL-positive staining. The results suggest that dietary Phase 2 inducers may protect against cancer by a mechanism distinct from and in addition to that associated with enhanced elimination of carcinogens. If this occurs in vivo, diets high in such compounds could eliminate precancerous cells by apoptosis at time points well after initial exposure to chemical mutagens and carcinogens.

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

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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.

65Zn kinetics as a biomarker of DMH induced colon carcinogenesis

International Nuclear Information System (INIS)

Chadha, Vijayta Dani

2012-01-01

Dietary factors are considered crucial for the prevention of initiating events in the multistep progression of colon carcinoma. There is substantial evidence that zinc may play a pivotal role in host defense against several malignancies, including colon cancer. The present study was conducted to evaluate the kinetics of zinc utilization following experimental colon carcinogenesis in rat model. The rats were segregated into two groups viz., untreated control and DMH treated. Colon carcinogenesis was established through weekly subcutaneous injections of DMH (30mg/Kg body weight) for 16 weeks. Whole body 65 Zn kinetics followed two compartment kinetics, with Tb1 representing the initial fast component of the biological half-life and Tb2, the slower component. The present study revealed a significant depression in the Tb1 and Tb2 components of 65 Zn in DMH treated rats. Further, DMH treatment caused a significant increase in the percent uptake values of 65 Zn in the colon, small intestine, kidney and blood, whereas a significant decrease was observed in the liver. Subcellular distribution revealed a significant increase in 65 Zn uptake in the mitochondrial and microsomal fractions following 16 weeks of DMH supplementation. The present study demonstrated a slow mobilization of zinc during promotion of experimentally induced colon carcinogenesis and provides a physiological basis for the role of zinc in colon tumorigenesis, a paradigm which may have clinical implications in the management of colon cancer. (author)

Inhibition of colon carcinogenesis by a standardized Cannabis sativa extract with high content of cannabidiol.

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Romano, Barbara; Borrelli, Francesca; Pagano, Ester; Cascio, Maria Grazia; Pertwee, Roger G; Izzo, Angelo A

2014-04-15

Colon cancer is a major public health problem. Cannabis-based medicines are useful adjunctive treatments in cancer patients. Here, we have investigated the effect of a standardized Cannabis sativa extract with high content of cannabidiol (CBD), here named CBD BDS, i.e. CBD botanical drug substance, on colorectal cancer cell proliferation and in experimental models of colon cancer in vivo. Proliferation was evaluated in colorectal carcinoma (DLD-1 and HCT116) as well as in healthy colonic cells using the MTT assay. CBD BDS binding was evaluated by its ability to displace [(3)H]CP55940 from human cannabinoid CB1 and CB2 receptors. In vivo, the effect of CBD BDS was examined on the preneoplastic lesions (aberrant crypt foci), polyps and tumours induced by the carcinogenic agent azoxymethane (AOM) as well as in a xenograft model of colon cancer in mice. CBD BDS and CBD reduced cell proliferation in tumoral, but not in healthy, cells. The effect of CBD BDS was counteracted by selective CB1 and CB2 receptor antagonists. Pure CBD reduced cell proliferation in a CB1-sensitive antagonist manner only. In binding assays, CBD BDS showed greater affinity than pure CBD for both CB1 and CB2 receptors, with pure CBD having very little affinity. In vivo, CBD BDS reduced AOM-induced preneoplastic lesions and polyps as well as tumour growth in the xenograft model of colon cancer. CBD BDS attenuates colon carcinogenesis and inhibits colorectal cancer cell proliferation via CB1 and CB2 receptor activation. The results may have some clinical relevance for the use of Cannabis-based medicines in cancer patients. Copyright © 2013 Elsevier GmbH. All rights reserved.

Role of neutral ceramidase in colon cancer.

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García-Barros, Mónica; Coant, Nicolas; Kawamori, Toshihiko; Wada, Masayuki; Snider, Ashley J; Truman, Jean-Philip; Wu, Bill X; Furuya, Hideki; Clarke, Christopher J; Bialkowska, Agnieszka B; Ghaleb, Amr; Yang, Vincent W; Obeid, Lina M; Hannun, Yusuf A

2016-12-01

Alterations in sphingolipid metabolism, especially ceramide and sphingosine 1-phosphate, have been linked to colon cancer, suggesting that enzymes of sphingolipid metabolism may emerge as novel regulators and targets in colon cancer. Neutral ceramidase (nCDase), a key enzyme in sphingolipid metabolism that hydrolyzes ceramide into sphingosine, is highly expressed in the intestine; however, its role in colon cancer has not been defined. Here we show that molecular and pharmacological inhibition of nCDase in colon cancer cells increases ceramide, and this is accompanied by decreased cell survival and increased apoptosis and autophagy, with minimal effects on noncancerous cells. Inhibition of nCDase resulted in loss of β-catenin and inhibition of ERK, components of pathways relevant for colon cancer development. Furthermore, inhibition of nCDase in a xenograft model delayed tumor growth and increased ceramide while decreasing proliferation. It is noteworthy that mice lacking nCDase treated with azoxymethane were protected from tumor formation. Taken together, these studies show that nCDase is pivotal for regulating initiation and development of colon cancer, and these data suggest that this enzyme is a suitable and novel target for colon cancer therapy.-García-Barros, M., Coant, N., Kawamori, T., Wada, M., Snider, A. J., Truman, J.-P., Wu, B. X., Furuya, H., Clarke, C. J., Bialkowska, A. B., Ghaleb, A., Yang, V. W., Obeid, L. M., Hannun, Y. A. Role of neutral ceramidase in colon cancer. © FASEB.

A new model to study the role of arachidonic acid in colon cancer pathophysiology

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Fan, Yang-Yi; Callaway, Evelyn; Monk, Jennifer M.; Goldsby, Jennifer S.; Yang, Peiying; Vincent, Logan; Chapkin, Robert S.

2016-01-01

A significant increase in cyclooxygenase 2 (COX2) gene expression has been shown to promote cylcooxygenase-dependent colon cancer development. Controversy associated with the role of COX2 inhibitors indicates that additional work is needed to elucidate the effects of arachidonic acid (AA) derived (cyclooxygenase and lipoxygenase) eicosanoids in cancer initiation, progression and metastasis. We have recently developed a novel Fads1 knockout mouse model, which allows for the investigation of AA-dependent eicosanoid deficiency without the complication of essential fatty acid deficiency. Interestingly, the survival rate of Fads1 null mice is severely compromised after 2 months on a semi-purified AA-free diet, which precludes long-term chemoprevention studies. Therefore, in this study, dietary AA levels were titrated to determine the minimal level required for survival, while maintaining a distinct AA-deficient phenotype. Null mice supplemented with AA (0.1, 0.4, 0.6, 2.0%, w/w) in the diet exhibited a dose-dependent increase (P diet were injected with a colon-specific carcinogen (azoxymethane) in order to assess cancer susceptibility. Null mice exhibited significantly (P < 0.05) reduced levels/multiplicity of aberrant crypt foci (ACF) as compared to wild type sibling littermate control mice. These data indicate that (i) basal/minimal dietary AA supplementation (0.6%) expands the utility of the Fads1 Null mouse model for long-term cancer prevention studies, and (ii) that AA content in the colonic epithelium modulates colon cancer risk. PMID:27339171

Protein S-glutathionylation induced by hypoxia increases hypoxia-inducible factor-1α in human colon cancer cells.

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Jeon, Daun; Park, Heon Joo; Kim, Hong Seok

2018-01-01

Hypoxia is a common characteristic of many types of solid tumors. Intratumoral hypoxia selects for tumor cells that survive in a low oxygen environment, undergo epithelial-mesenchymal transition, are more motile and invasive, and show gene expression changes driven by hypoxia-inducible factor-1α (HIF-1α) activation. Therefore, targeting HIF-1α is an attractive strategy for disrupting multiple pathways crucial for tumor growth. In the present study, we demonstrated that hypoxia increases the S-glutathionylation of HIF-1α and its protein levels in colon cancer cells. This effect is significantly prevented by decreasing oxidized glutathione as well as glutathione depletion, indicating that S-glutathionylation and the formation of protein-glutathione mixed disulfides is related to HIF-1α protein levels. Moreover, colon cancer cells expressing glutaredoxin 1 are resistant to inducing HIF-1α and expressing hypoxia-responsive genes under hypoxic conditions. Therefore, S-glutathionylation of HIF-1α induced by tumor hypoxia may be a novel therapeutic target for the development of new drugs. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective Immunity and Reduced Renal Colonization Induced by Vaccines Containing Recombinant Leptospira interrogans Outer Membrane Proteins and Flagellin Adjuvant

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Monaris, D.; Sbrogio-Almeida, M. E.; Dib, C. C.; Canhamero, T. A.; Souza, G. O.; Vasconcellos, S. A.; Ferreira, L. C. S.

2015-01-01

Leptospirosis is a global zoonotic disease caused by different Leptospira species, such as Leptospira interrogans, that colonize the renal tubules of wild and domestic animals. Thus far, attempts to develop effective leptospirosis vaccines, both for humans and animals, have failed to induce immune responses capable of conferring protection and simultaneously preventing renal colonization. In this study, we evaluated the protective immunity induced by subunit vaccines containing seven different recombinant Leptospira interrogans outer membrane proteins, including the carboxy-terminal portion of the immunoglobulinlike protein A (LigAC) and six novel antigens, combined with aluminum hydroxide (alum) or Salmonella flagellin (FliC) as adjuvants. Hamsters vaccinated with the different formulations elicited high antigen-specific antibody titers. Immunization with LigAC, either with alum or flagellin, conferred protective immunity but did not prevent renal colonization. Similarly, animals immunized with LigAC or LigAC coadministered with six leptospiral proteins with alum adjuvant conferred protection but did not reduce renal colonization. In contrast, immunizing animals with the pool of seven antigens in combination with flagellin conferred protection and significantly reduced renal colonization by the pathogen. The present study emphasizes the relevance of antigen composition and added adjuvant in the efficacy of antileptospirosis subunit vaccines and shows the complex relationship between immune responses and renal colonization by the pathogen. PMID:26108285

Celecoxib induces proliferation and Amphiregulin production in colon subepithelial myofibroblasts, activating erk1-2 signaling in synergy with EGFR.

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Benelli, Roberto; Venè, Roberta; Minghelli, Simona; Carlone, Sebastiano; Gatteschi, Beatrice; Ferrari, Nicoletta

2013-01-01

The COX-2 inhibitor Celecoxib, tested in phase III trials for the prevention of sporadic colon adenomas, reduced the appearance of new adenomas, but was unable to affect the incidence of colon cancer. Moreover the 5years follow-up showed that patients discontinuing Celecoxib treatment had an increased incidence of adenomas as compared to the placebo arm. In the APC(min/+) mouse model short term treatment with Celecoxib reduced gut adenomas, but a prolonged administration of the drug induced fibroblast activation and intestinal fibrosis with a final tumor burden. The way Celecoxib could directly activate human colon myofibroblasts (MF) has not yet been investigated. We found that MF are activated by non toxic doses of Celecoxib. Celecoxib induces erk1-2 and Akt phosphorylation within 5'. This short term activation is apparently insufficient to cause phenotypic changes, but the contemporary triggering of EGFR causes an impressive synergic effect inducing MF proliferation and the neo-expression and release of Amphiregulin (AREG), a well known EGFR agonist involved in colon cancer progression. As a confirm to these observations, the erk inhibitor U0126 and the EGFR inhibitors Tyrphostin and Cetuximab were able to contrast AREG induction. Our data provide evidence that Celecoxib directly activates MF empowering EGFR signaling. According to these results the association with EGFR (or erk1-2) inhibitors could abolish the off-target activity of Celecoxib, possibly extending the potential of this drug for colon cancer prevention. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Immunohistochemical study of p53 overexpression in radiation-induced colon cancers

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Minami, Kazunori; Hayashi, Nobuyuki; Mokarim, A.; Matsuzaki, Sumihiro; Ito, Masahiro; Sekine, Ichiro.

1998-01-01

The expressions of p53 and proliferating cell nuclear antigen (PCNA) were studied immunohistochemically from paraffin sections of 7 cases (9 lesions) of radiation-induced colon cancer and 42 cases of spontaneous colon cancer. Age distribution of radiation-induced and spontaneous colon cancer were 68.1 years (range, 56 to 77 years) and 67.4 years (range, 31 to 85 years), respectively. Among the radiation-induced colon cancers, there were 3 lesions of mucinous carcinoma (33%), a much higher than found for spontaneous mucinous cancer. Immunohistochemically, p53 protein expression was detected in 7/9 (78%) of radiation-induced cancers and in 23/42 (55%) of spontaneous colon cancers. χ 2 analysis found no significant differences between radiation-induced and spontaneous colon cancers in age distribution or p53-positive staining for frequency, histopathology, or Dukes'' classification. In radiation colitis around the cancers including aberrant crypts, spotted p53 staining and abnormal and scattered PCNA-positive staining were observed. In histologically normal cells, p53 staining was almost absent and PCNA-positive staining was regularly observed in the lower half of the crypt. In radiation colitis including aberrant glands, cellular proliferation increased and spotted p53 expression was observed. This study suggests that radiation colitis and aberrant glands might possess malignant potential and deeply associate with carcinogenesis of radiation-induced colon cancer. (author)

Conjugated Linoleic Acid Ameliorates Inflammation-Induced Colorectal Cancer in Mice through Activation of PPARγ1–3

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Evans, Nicholas P.; Misyak, Sarah A.; Schmelz, Eva M.; Guri, Amir J.; Hontecillas, Raquel; Bassaganya-Riera, Josep

2010-01-01

Conjugated linoleic acid (CLA) exerts a protective effect on experimental inflammatory bowel disease and shows promise as a chemopreventive agent against colorectal cancer (CRC) in mice, although the mechanisms by which it exerts its beneficial effects against malignancies in the gut are not completely understood. Mice lacking PPARγ in immune and epithelial cells and PPARγ-expressing littermates were fed either control or CLA-supplemented (1 g CLA/100 g) diets to determine the role of PPARγ in inflammation-induced CRC. To induce tumor formation and colitis, mice were treated with azoxymethane and then challenged with 2% dextran sodium sulfate, respectively. Dietary CLA ameliorated disease activity, decreased colitis, and prevented adenocarcinoma formation in the PPARγ-expressing floxed mice but not in the tissue-specific PPARγ-null mice. Dietary CLA supplementation significantly decreased the percentages of macrophages in the mesenteric lymph nodes (MLN) regardless of the genotype and increased regulatory T cell numbers in MLN of PPARγ-expressing, but not in the tissue-specific, PPARγ-null mice. Colonic tumor necrosis factor-α mRNA expression was significantly suppressed in CLA-fed, PPARγ-expressing mice. This study suggests CLA ameliorates colitis and prevents tumor formation in part through a PPARγ-dependent mechanism. PMID:20089779

Celecoxib prevents colitis associated colon carcinogenesis: an upregulation of apoptosis.

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Setia, Shruti; Nehru, Bimla; Sanyal, Sankar N

2014-12-01

Uncontrolled cell proliferation and suppressed apoptosis are the critical events transforming a normal cell to a cancerous one wherein the inflammatory microenvironment supports this oncogenic transformation. The process of colon carcinogenesis may be aggravated in chronic inflammatory conditions such as ulcerative colitis where non-steroidal anti-inflammatory drugs (NSAIDs) may effectively prevent the cellular and molecular events. Western blots and immunofluorescent analysis of DNA mismatch repair enzymes, cell cycle regulators and pro- and anti-apoptotic proteins were performed in dextran sulfate sodium (DSS)-induced ulcerative colitis and 1,2-dimethyl benz(a)anthracene (DMH)-induced colon cancer. Also, apoptotic studies were done in isolated colonocytes using fluorescent staining and in paraffin sections using TUNEL assay. An upregulation of cell cycle regulators: cyclin D1/cdk4 and cyclin E/cdk2 and anti-apoptotic Bcl-2, along with the suppression of DNA repair enzymes: MLH1 and MSH2; tumour suppressors: p53, p21and Rb and pro-apoptotic proteins: Bax and Bad were observed in the DSS, DMH and DSS+DMH groups. Proliferating cell nuclear antigen (PCNA) was also overexpressed in these groups. The ultimate executioner of the apoptotic pathway; caspase-3, was suppressed in these groups. Apoptotic studies in colonocytes and paraffin sections revealed suppressed apoptosis in these groups. These effects were corrected with the administration of a second generation NSAID, celecoxib along with the treatment of DSS and DMH. The chemopreventive action of celecoxib in colitis mediated colon carcinogenesis may include the regulation of DNA mismatch repair enzymes, cell cycle check points, cell proliferation and apoptosis. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

δ- and γ-tocopherols inhibit phIP/DSS-induced colon carcinogenesis by protection against early cellular and DNA damages.

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Chen, Jayson X; Liu, Anna; Lee, Mao-Jung; Wang, Hong; Yu, Siyuan; Chi, Eric; Reuhl, Kenneth; Suh, Nanjoo; Yang, Chung S

2017-01-01

Tocopherols, the major forms of vitamin E, are a family of fat-soluble compounds that exist in alpha (α-T), beta (β-T), gamma (γ-T), and delta (δ-T) variants. A cancer preventive effect of vitamin E is suggested by epidemiological studies. However, past animal studies and human intervention trials with α-T, the most active vitamin E form, have yielded disappointing results. A possible explanation is that the cancer preventive activity of α-T is weak compared to other tocopherol forms. In the present study, we investigated the effects of δ-T, γ-T, and α-T (0.2% in diet) in a novel colon cancer model induced by the meat-derived dietary carcinogen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and promoted by dextran sodium sulfate (DSS)-induced colitis in CYP1A-humanized (hCYP1A) mice. PhIP/DSS treatments induced multiple polypoid tumors, mainly tubular adenocarcinomas, in the middle to distal colon of the hCYP1A mice after 10 wk. Dietary supplementation with δ-T and γ-T significantly reduced colon tumor formation and suppressed markers of oxidative and nitrosative stress (i.e., 8-oxo-dG and nitrotyrosine) as well as pro-inflammatory mediators (i.e., NF-κB p65 and p-STAT3) in tumors and adjacent tissues. By administering δ-T at different time periods, we obtained results suggesting that the inhibitory effect of δ-T against colon carcinogenesis is mainly due to protection against early cellular and DNA damages caused by PhIP. α-T was found to be ineffective in inhibiting colon tumors and less effective in attenuating the molecular changes. Altogether, we demonstrated strong cancer preventive effects of δ-T and γ-T in a physiologically relevant model of human colon cancer. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Chemo prevention of Tea Polyphenols against Tumor Growth of Hepato-Colon Cancer Induced by Azoxy methane in Rats

International Nuclear Information System (INIS)

Heibashy, M.I.A.; Mazen, G.M.A.

2008-01-01

This investigation was conducted to evaluate the chemo prevention of tea polyphenols as anticancer agent in rats which were injected with azoxy methane (AOM) which is a potent hepato-colon carcinogen agents in rodents. The obtained data revealed a significant elevation in serum tumor markers, carcino-embryonic antigen (CEA), alpha-fetoprotein (AFP) and cancer antigen (CA 1 9.9) in carcinogenic rats in comparison to their corresponding normal control ones. Also, there was a significant increase in the content of cytochrome P 4 50 and the activity of alcohol dehydrogenase (ADH) in both liver and colon as well as a significant elevation in the activities of methoxyresorufin-O-dealkylase (MRD), ethoxyresorutin-O-dealkylase (ERD) and pentoxyresorufin-O- dealkylase (PRD) in liver microsomes. While, glutathione content (GSH) and glutathione peroxidase (Gp x ) activity were decreased significantly in liver and colon as a result of cancer induction. On the other hand, the supplementation of black or green tea before induction of cancer in rats led to a considerable correction in all previous parameters studied. These amelioration effects dependent on magic biochemical properties of flavanols (catechins) and type of tea. In conclusion, tea polyphenols have appreciable anti-cancer efficacy on hepato colon cancer in rats. The underlying mechanisms of through which tea counteracted hepato-colon cancer were discussed

Role of pomegranate and citrus fruit juices in colon cancer prevention

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Jaganathan, Saravana Kumar; Vellayappan, Muthu Vignesh; Narasimhan, Gayathri; Supriyanto, Eko

2014-01-01

Colorectal cancer is the second leading cause of cancer-related deaths in the United States. Recent studies prove that though chemotherapeutic agents are being used for the treatment of colon cancer, they become non-effective when the cancer progresses to an invasive stage. Since consumption of certain dietary agents has been linked with various cancers, fruit juices have been investigated for their consistently protective effect against colon cancer. The unique biochemical composition of fruit juices is responsible for their anticancer properties. In this review, the chemo-preventive effect of fruit juices such as pomegranate and citrus juices against colon cancer are discussed. For this purpose, the bioavailability, in vitro and in vivo effects of these fruit juices on colorectal cancer are highlighted. Moreover, there is a scarcity of studies involving human trials to estimate the preventive nature of these juices against colon cancer. This review will support the need for more preclinical tests with these crude juices and their constituents in different colorectal cancer cell lines and also some epidemiological studies in order to have a better understanding and promote pomegranate and citrus juices as crusaders against colon cancer. PMID:24782614

Colonic aberrant crypt formation accompanies an increase of opportunistic pathogenic bacteria in C57BL/6 mice fed a high-fat diet.

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Zeng, Huawei; Ishaq, Suzanne L; Liu, Zhenhua; Bukowski, Michael R

2018-04-01

The increasing worldwide incidence of colon cancer has been linked to obesity and consumption of a high-fat Western diet. To test the hypothesis that a high-fat diet (HFD) promotes colonic aberrant crypt (AC) formation in a manner associated with gut bacterial dysbiosis, we examined the susceptibility to azoxymethane (AOM)-induced colonic AC and microbiome composition in C57/BL6 mice fed a modified AIN93G diet (AIN, 16% fat, energy) or an HFD (45% fat, energy) for 14 weeks. Mice receiving the HFD exhibited increased plasma leptin, body weight, body fat composition and inflammatory cell infiltration in the ileum compared with those in the AIN group. Consistent with the gut inflammatory phenotype, we observed an increase in colonic AC, plasma interleukin-6, tumor necrosis factor-α, monocyte chemoattractant protein-1 and inducible nitric oxide synthase in the ileum of the HFD-AOM group compared with the AIN-AOM group. Although the HFD and AIN groups did not differ in bacterial species number, the HFD and AIN diets resulted in different bacterial community structures in the colon. The abundance of certain short-chain fatty acid (SCFA) producing bacteria (e.g., Barnesiella) and fecal SCFA (e.g., acetic acid) content were lower in the HFD-AOM group compared with the AIN and AIN-AOM groups. Furthermore, we identified a high abundance of Anaeroplasma bacteria, an opportunistic pathogen in the HFD-AOM group. Collectively, we demonstrate that an HFD promotes AC formation concurrent with an increase of opportunistic pathogenic bacteria in the colon of C57BL/6 mice. Published by Elsevier Inc.

Effect of diets fortified with tomatoes or onions with variable quercetin-glycoside content on azoxymethane-induced aberrant crypt foci in the colon of rats

NARCIS (Netherlands)

Femia, A.P.; Caderni, G.; Ianni, M.; Salvadori, M.; Schijlen, E.G.W.M.; Collins, G.; Bovy, A.G.; Dolara, P.

2003-01-01

Background: Onion and tomato are vegetables widely consumed by humans and epidemiological studies show an inverse association between vegetable consumption and colon cancer risk; however, the effect on colon cancer of diets containing high levels of vegetables like onion and tomato are not clear.

Lectin histochemistry of 1,2-dimethylhydrazine-induced rat colon neoplasia.

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Freeman, H J

1983-10-01

Lectins linked to fluorescein were used as carbohydrate probes to examine the goblet cell mucin and epithelial cell surface glycoconjugate alterations in an experimental rodent model of colonic neoplasia induced with parenteral 1,2-dimethylhydrazine dihydrochloride. Lectins derived from Triticum vulgare (WGA), Ricinus communis (RCA1), and Limulus polyphemus (LPA) showed reduced labeling of goblet cell mucin in these tumors, while binding with peanut lectin from Arachis hypogaea (PNA), a lectin ordinarily failing to bind to mucin in normal colon, was positive. In addition, RCA1 and LPA showed increased cell surface labeling of neoplastic epithelial cells. Finally, alterations were observed in lectin binding to "transitional" colonic mucosa adjacent to colonic tumors from carcinogen-treated rats. These findings indicate that significant alterations in both membrane and mucin glycoconjugates occur in colonic tumors and mucosa adjacent to tumors in a chemically induced experimental animal model of human colon cancer.

MicroRNA-449a deficiency promotes colon carcinogenesis.

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Niki, Masanori; Nakajima, Kohei; Ishikawa, Daichi; Nishida, Jun; Ishifune, Chieko; Tsukumo, Shin-Ichi; Shimada, Mitsuo; Nagahiro, Shinji; Mitamura, Yoshinori; Yasutomo, Koji

2017-09-06

MicroRNAs have broad roles in tumorigenesis and cell differentiation through regulation of target genes. Notch signaling also controls cell differentiation and tumorigenesis. However, the mechanisms through which Notch mediates microRNA expression are still unclear. In this study, we aimed to identify microRNAs regulated by Notch signaling. Our analysis found that microRNA-449a (miR-449a) was indirectly regulated by Notch signaling. Although miR-449a-deficient mice did not show any Notch-dependent defects in immune cell development, treatment of miR-449a-deficient mice with azoxymethane (AOM) or dextran sodium sulfate (DSS) increased the numbers and sizes of colon tumors. These effects were associated with an increase in intestinal epithelial cell proliferation following AOM/DSS treatment. In patients with colon cancer, miR-449a expression was inversely correlated with disease-free survival and histological scores and was positively correlated with the expression of MLH1 for which loss-of function mutations have been shown to be involved in colon cancer. Colon tissues of miR-449a-deficient mice showed reduced Mlh1 expression compared with those of wild-type mice. Thus, these data suggested that miR-449a acted as a key regulator of colon tumorigenesis by controlling the proliferation of intestinal epithelial cells. Additionally, activation of miR-449a may represent an effective therapeutic strategy and prognostic marker in colon cancer.

Mesenchymal stem cells and conditioned medium avert enteric neuropathy and colon dysfunction in guinea pig TNBS-induced colitis.

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Robinson, Ainsley M; Sakkal, Samy; Park, Anthony; Jovanovska, Valentina; Payne, Natalie; Carbone, Simona E; Miller, Sarah; Bornstein, Joel C; Bernard, Claude; Boyd, Richard; Nurgali, Kulmira

2014-12-01

Damage to the enteric nervous system (ENS) associated with intestinal inflammation may underlie persistent alterations to gut functions, suggesting that enteric neurons are viable targets for novel therapies. Mesenchymal stem cells (MSCs) offer therapeutic benefits for attenuation of neurodegenerative diseases by homing to areas of inflammation and exhibiting neuroprotective, anti-inflammatory, and immunomodulatory properties. In culture, MSCs release soluble bioactive factors promoting neuronal survival and suppressing inflammation suggesting that MSC-conditioned medium (CM) provides essential factors to repair damaged tissues. We investigated whether MSC and CM treatments administered by enema attenuate 2,4,6-trinitrobenzene-sulfonic acid (TNBS)-induced enteric neuropathy and motility dysfunction in the guinea pig colon. Guinea pigs were randomly assigned to experimental groups and received a single application of TNBS (30 mg/kg) followed by 1 × 10(6) human bone marrow-derived MSCs, 300 μl CM, or 300 μl unconditioned medium 3 h later. After 7 days, the effect of these treatments on enteric neurons was assessed by histological, immunohistochemical, and motility analyses. MSC and CM treatments prevented inflammation-associated weight loss and gross morphological damage in the colon; decreased the quantity of immune infiltrate in the colonic wall (P ChAT, and nNOS immunoreactivity (P < 0.05); and alleviated inflammation-induced colonic dysmotility (contraction speed; P < 0.001, contractions/min; P < 0.05). These results provide strong evidence that both MSC and CM treatments can effectively prevent damage to the ENS and alleviate gut dysfunction caused by TNBS-induced colitis. Copyright © 2014 the American Physiological Society.

Lucky number seven: RNase 7 can prevent Staphylococcus aureus skin colonization.

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Cho, John S; Xuan, Caiyun; Miller, Lloyd S

2010-12-01

Staphylococcus aureus colonization is a major risk factor for infection. In this issue, Simanski et al. demonstrate that the antimicrobial peptide RNase 7 is essential for preventing S. aureus colonization in human skin. These findings suggest that therapeutic interventions aimed at targeting RNase 7 production in the skin may be a novel strategy to protect against S. aureus infections.

Effect of complex polyphenols on colon carcinogenesis.

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Caderni, G; Remy, S; Cheynier, V; Morozzi, G; Dolara, P

1999-06-01

Complex polyphenols and tannins from wine (WCPT) are being considered increasingly as potential cancer chemopreventive agents, since epidemiological studies suggest that populations consuming a high amount of polyphenols in the diet may have a lower incidence of some types of cancer. We studied the effect of WCPT on a series of parameters related to colon carcinogenesis in rats. WCPT were administered to F344 rats at a dose of 14 or 57 mg/kg/d, mixed with the diet. The higher dose is about ten times the exposure to polyphenols of a moderate drinker of red wine. In rats treated with WCPT, we measured fecal bile acids and long chain fatty acids, colon mucosa cell proliferation, apoptosis and, after administration of colon carcinogens, the number and size of aberrant crypt foci (ACF) and nuclear aberrations. Colon mucosa proliferation was not varied by chronic administration (90 d) of WCPT (14 or 57 mg/kg/d). The highest dose of WCPT decreased the number of cells in the colon crypts, but did not increase apoptosis. WCPT (57 mg/kg) administered before or after the administration of azoxymethane (AOM) did not vary the number or multiplicity of ACF in the colon. The number of nuclear aberrations (NA) in colon mucosa was studied after administration of 1,2-dimethylhydrazine (DMH) and 2-amino-3-methylimidazo (4,5-f)quinoline (IQ), colon-specific carcinogens which require metabolic activation. The effect of DMH and IQ was not varied by pre-feeding WCPT (57 mg/kg) for 10 d. Similarly, the levels of total, secondary bile acids and long chain fatty acids did not varied significantly in animals fed WCPT for 90 d. WCPT administration does not influence parameters related to colon carcinogenesis in the rat.

Sucrose and IQ induced mutations in rat colon by independent

DEFF Research Database (Denmark)

Hansen, Max; Hald, M. T.; Autrup, H.

2004-01-01

Sucrose-rich diets have repeatedly been observed to have co-carcinogenic actions in colon and liver of rats and to increase the number of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) induced aberrant crypt foci in rat colon. To investigate a possible interaction between sucrose and IQ...... on the genotoxicity in rat liver and colon, we gave Big Blue rats(TM) a diet containing sucrose (0%, 3.45% or 13.4% w/w) and/or IQ (70 ppm) for a period of 3 weeks. Sucrose and IQ increased the mutation frequency in the colon. The effect of combined treatments with IQ and sucrose on the mutation frequencies...... was additive indicating that sucrose and IQ act independently. This was supported by the mutation spectra where sucrose expands the background mutations in the colon, whereas IQ, in other studies, more specifically has induced G:C --> T:A transversions. In the liver IQ increased the mutation frequency, whereas...

Chemoprevention by Probiotics During 1,2-Dimethylhydrazine-Induced Colon Carcinogenesis in Rats.

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Walia, Sohini; Kamal, Rozy; Dhawan, D K; Kanwar, S S

2018-04-01

Probiotics are believed to have properties that lower the risk of colon cancer. However, the mechanisms by which they exert their beneficial effects are relatively unknown. To assess the impact of probiotics in preventing induction of colon carcinogenesis in rats. The rats were divided into six groups viz., normal control, Lactobacillus plantarum (AdF10)-treated, Lactobacillus rhamnosus GG (LGG)-treated, 1,2-dimethylhydrazine (DMH)-treated, L. plantarum (AdF10) + DMH-treated and L. rhamnosus GG (LGG) + DMH-treated. Both the probiotics were supplemented daily at a dose of 2 × 10 10 cells per day. DMH at a dose of 30 mg/kg body weight was administered subcutaneously twice a week for the first 4 weeks and then once every week for a duration of 16 weeks. Glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and catalase as protein expression of genes involved in apoptosis were assessed during DMH-induced colon carcinogenesis in rats. DMH treatment decreased the activity of GSH, GPx, GST, SOD and catalase. However, AdF10 and LGG supplementation to DMH-treated rats significantly increased the activity of these enzymes. Further, DMH treatment revealed alterations in the protein expressions of various genes involved in the p53-mediated apoptotic pathway such as p53, p21, Bcl-2, Bax, caspase-9 and caspase-3, which, however, were shifted towards normal control levels upon simultaneous supplementation with probiotics. The present study suggests that probiotics can provide protection against oxidative stress and apoptotic-related protein disregulation during experimentally induced colon carcinogenesis.

Intestinal colonization of IL-2 deficient mice with non-colitogenic B. vulgatus prevents DC maturation and T-cell polarization.

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Martina Müller

Full Text Available BACKGROUND: IL-2 deficient (IL-2(-/- mice mono-colonized with E. coli mpk develop colitis whereas IL-2(-/--mice mono-colonized with B. vulgatus mpk do not and are even protected from E. coli mpk induced colitis. METHODOLOGY/PRINCIPAL FINDINGS: We investigated if mono-colonization with E. coli mpk or B. vulgatus mpk differentially modulates distribution, activation and maturation of intestinal lamina propria (LP dendritic cells (DC. LP DC in mice mono-colonized with protective B. vulgatus mpk or co-colonized with E. coli mpk/B. vulgatus mpk featured a semi-mature LP DC phenotype (CD40(loCD80(loMHC-II(hi whereas mono-colonization with colitogenic E. coli mpk induced LP DC activation and maturation prior to onset of colitis. Accordingly, chemokine receptor (CCR 7 surface expression was more strikingly enhanced in mesenteric lymph node DC from E. coli mpk than B. vulgatus mpk mono- or co-colonized mice. Mature but not semi-mature LP DC promoted Th1 polarization. As B. vulgatus mpk promotes differentiation of semi-mature DC presumably by IL-6, mRNA and protein expression of IL-6 was investigated in LP DC. The data demonstrated that IL-6 mRNA and protein was increased in LP DC of B. vulgatus mpk as compared to E. coli mpk mono-colonized IL-2(-/--mice. The B. vulgatus mpk mediated suppression of CCR7 expression and DC migration was abolished in IL-6(-/--DC in vitro. CONCLUSIONS/SIGNIFICANCE: From this data we conclude that the B. vulgatus triggered IL-6 secretion by LP DC in absence of proinflammatory cytokines such as IL-12 or TNF-alpha induces a semi-mature LP DC phenotype, which might prevent T-cell activation and thereby the induction of colitis in IL-2(-/--mice. The data provide new evidence that IL-6 might act as an immune regulatory cytokine in the mucosa by targeting intestinal DC.

Lactobacillus salivarius Ren prevent the early colorectal carcinogenesis in 1, 2-dimethylhydrazine-induced rat model.

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Zhu, J; Zhu, C; Ge, S; Zhang, M; Jiang, L; Cui, J; Ren, F

2014-07-01

The objective of this study was to investigate the impact of Lactobacillus salivarius Ren (LS) on modulating colonic micro flora structure and influencing host colonic health in a rat model with colorectal precancerous lesions. Male F344 rats were injected with 1, 2-dimethylhydrazine (DMH) and treated with LS of two doses (5 × 10(8) and 1 × 10(10) CFU kg(-1) body weight) for 15 weeks. The colonic microflora profiles, luminal metabolites, epithelial proliferation and precancerous lesions [aberrant crypt foci (ACF)] were determined. A distinct segregation of colonic microflora structures was observed in LS-treated group. The abundance of one Prevotella-related strain was increased, and the abundance of one Bacillus-related strain was decreased by LS treatment. These changes were accompanied by increased short-chain fatty acid levels and decreased azoreductase activity. LS treatment also reduced the number of ACF by c. 40% and suppressed epithelial proliferation. Lactobacillus salivarius Ren improved the colonic microflora structures and the luminal metabolisms in addition preventing the early colorectal carcinogenesis in DMH-induced rat model. Colonic microflora is an important factor in colorectal carcinogenesis. Modulating the structural shifts of microflora may provide a novel option for preventing colorectal carcinogenesis. This study suggested a potential probiotic-based approach to modulate the intestinal microflora in the prevention of colorectal carcinogenesis. © 2014 The Society for Applied Microbiology.

Lactobacillus rhamnosus induced epithelial cell apoptosis, ameliorates inflammation and prevents colon cancer development in an animal model.

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Gamallat, Yaser; Meyiah, Abdo; Kuugbee, Eugene D; Hago, Ahmed Musa; Chiwala, Gift; Awadasseid, Annoor; Bamba, Djibril; Zhang, Xin; Shang, Xueqi; Luo, Fuwen; Xin, Yi

2016-10-01

Probiotics have been suggested as prophylactic measure in colon carcinogenesis. This study aimed at determining the potential prophylactic activity of Lactobacillus rhamnosus GG CGMCC 1.2134 (LGG) strain on colorectal carcinogenesis via measuring its effect on Nuclear factor kappa B (NFκB) inflammatory pathway and apoptosis. 64 Sprague Dawley rats were grouped into four as follows; Group 1 (Healthy control), Group 2 (LGG), Group 3 (cancer control Dimethyl hydrazine (DMH)) and Group 4 (LGG+DMH). LGG was administered orally to LGG and LGG+DMH groups. Colon carcinogenesis was chemically induced in LGG+DMH and DMH groups by weekly injection of 40mg/kg DMH. Animals were sacrificed after 25 weeks of experiment and tumor characteristics assessed. The change in expression of NFκB-p65, COX-2, TNFα, Bcl-2, Bax, iNOS, VEGFα, β-catenin, Casp3 and p53 were evaluated by western blotting and qRT-PCR. LGG treatment significantly reduced tumor incidence, multiplicity and volume in LGG+DMH treatment group compared to DMH cancer control group. Also, LGG treatment reduced the expression of β-catenin and the inflammatory proteins NFκB-p65, COX-2 and TNFα; the anti-apoptotic protein Bcl-2, but increased the expression of the pro-apoptotic proteins Bax, casp3 and p53 compared with DMH group. LGG have a potential protection effect against colon carcinogenesis; inducing apoptosis and ameliorating inflammation, and may hold a promise as bio-therapeutic dietary agent. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Red meat and colon cancer : dietary haem-induced colonic cytotoxicity and epithelial hyperproliferation are inhibited by calcium

NARCIS (Netherlands)

Sesink, ALA; Termont, DSML; Kleibeuker, JH; Van der Meer, R

2001-01-01

High intake of red meat is associated with increased colon cancer risk. We have shown earlier that this may be due to the high haem content of red meat, because dietary haem increased cytolytic activity of faecal water and colonic epithelial proliferation. Dietary calcium inhibits diet-induced

Pre-treatment with Bifidobacterium breve UCC2003 modulates Citrobacter rodentium-induced colonic inflammation and organ specificity.

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Collins, James W; Akin, Ali R; Kosta, Artemis; Zhang, Ning; Tangney, Mark; Francis, Kevin P; Frankel, Gad

2012-11-01

Citrobacter rodentium, which colonizes the gut mucosa via formation of attaching and effacing (A/E) lesions, causes transmissible colonic hyperplasia. The aim of this study was to evaluate whether prophylactic treatment with Bifidobacterium breve UCC2003 can improve the outcome of C. rodentium infection. Six-week-old albino C57BL/6 mice were pre-treated for 3 days with B. breve, challenged with bioluminescent C. rodentium and administered B. breve or PBS-C for 8 days post-infection; control mice were either administered B. breve and mock-infected with PBS, or mock-treated with PBS-C and mock-infected with PBS. C. rodentium colonization was monitored by bacterial enumeration from faeces and by a combination of both 2D bioluminescence imaging (BLI) and composite 3D diffuse light imaging tomography with µCT imaging (DLIT-µCT). At day 8 post-infection, colons were removed and assessed for crypt hyperplasia, histology by light microscopy, bacterial colonization by immunofluorescence, and A/E lesion formation by electron microscopy. Prophylactic administration of B. breve did not prevent C. rodentium colonization or A/E lesion formation. However, this treatment did alter C. rodentium distribution within the large intestine and significantly reduced colonic crypt hyperplasia at the peak of bacterial infection. These results show that B. breve could not competitively exclude C. rodentium, but reduced pathogen-induced colonic inflammation.

Effect of dietary fiber on the activity of intestinal and fecal beta-glucuronidase activity during 1,2-dimethylhydrazine induced colon carcinogenesis.

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Manoj, G; Thampi, B S; Leelamma, S; Menon, P V

2001-01-01

The effects of fiber isolated from black gram (Phaseolus mungo) and coconut (Cocos nucifera) kernel on the metabolic activity of intestinal and fecal beta glucuronidase activity during 1,2-dimethylhydrazine induced colon carcinogenesis were studied. The results indicated that the inclusion of fiber from black gram and coconut kernel generally supported lower specific activities and less fecal output of beta-glucuronidase than did the fiber free diet. This study suggests that the fibers isolated from coconut or black gram may potentially play a role in preventing the formation of colon tumors induced by the carcinogen 1,2-dimethylhydrazine by reducing the activity of the intestinal as well as fecal beta-glucuronidase.

Identifying molecular targets of lifestyle modifications in colon cancer prevention

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Molly Marie Derry

2013-05-01

Full Text Available One in four deaths in the United States is cancer-related, and colorectal cancer (CRC is the second leading cause of cancer-associated deaths. Screening strategies are utilized but have not reduced disease incidence or mortality. In this regard, there is an interest in cancer preventive strategies focusing on lifestyle intervention, where specific etiologic factors involved in cancer initiation, promotion, and progression could be targeted. For example, exposure to dietary carcinogens, such as nitrosamines and polycyclic aromatic hydrocarbons influences colon carcinogenesis. Furthermore, dietary deficiencies could alter sensitivity to genetic damage and influence carcinogen metabolism contributing to CRC. High alcohol consumption increases the risk of mutations including the fact that acetaldehyde, an ethanol metabolite, is classified as a group 1 carcinogen. Tobacco smoke exposure is also a risk factor for cancer development; ~20% of CRCs are associated with smoking. Additionally, obese patients have a higher risk of cancer development, which is further supported by the fact that physical activity decreases CRC risk by 55%. Similarly, chronic inflammatory conditions also increase the risk of CRC development. Moreover, the circadian clock alters digestion and regulates other biochemical, physiological and behavioral processes that could positively influence CRC. Taken together, colon carcinogenesis involves a number of etiological factors, and therefore, to create effective preventive strategies, molecular targets need to be identified and beleaguered prior to disease progression. With this in mind, the following is a comprehensive review identifying downstream target proteins of the above lifestyle risk factors, which are modulated during colon carcinogenesis and could be targeted for CRC prevention by novel agents including phytochemicals.

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

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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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

Triptolide downregulates Rac1 and the JAK/STAT3 pathway and inhibits colitis-related colon cancer progression

DEFF Research Database (Denmark)

Wang, Zhipeng; Jin, Haifeng; Xu, Ruodan

2009-01-01

ability to block progress of colitis to colon cancer, and its molecular mechanism of action are investigated. A mouse model for colitis-induced colorectal cancer was used to test the effect of triptolide on cancer progression. Treatment of mice with triptolide decreased the incidence of colon cancer...... formation, and increased survival rate. Moreover, triptolide decreased the incidence of tumors in nude mice inoculated with cultured colon cancer cells dose-dependently. In vitro, triptolide inhibited the proliferation, migration and colony formation of colon cancer cells. Secretion of IL6 and levels of JAK....... This suggests that triptolide might be a candidate for prevention of colitis induced colon cancer because it reduces inflammation and prevents tumor formation and development....

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.

Maternal antibiotic-induced early changes in microbial colonization selectively modulate colonic permeability and inducible heat shock proteins, and digesta concentrations of alkaline phosphatase and TLR-stimulants in swine offspring.

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Marie-Edith Arnal

Full Text Available Elevated intake of high energy diets is a risk factor for the development of metabolic diseases and obesity. High fat diets cause alterations in colonic microbiota composition and increase gut permeability to bacterial lipopolysaccharide, and subsequent low-grade chronic inflammation in mice. Chronic inflammatory bowel diseases are increasing worldwide and may involve alterations in microbiota-host dialog. Metabolic disorders appearing in later life are also suspected to reflect changes in early programming. However, how the latter affects the colon remains poorly studied. Here, we hypothesized that various components of colonic physiology, including permeability, ion exchange and protective inducible heat shock proteins (HSP are influenced in the short- and long-terms by early disturbances in microbial colonization. The hypothesis was tested in a swine model. Offspring were born to control mothers (n = 12 or mothers treated with the antibiotic (ATB amoxicillin around parturition (n = 11. Offspring were slaughtered between 14 and 42 days of age to study short-term effects. For long-term effects, young adult offspring from the same litters consumed a normal or a palm oil-enriched diet for 4 weeks between 140 and 169 days of age. ATB treatment transiently modified maternal fecal microbiota although the minor differences observed for offspring colonic microbiota were nonsignificant. In the short-term, consistently higher HSP27 and HSP70 levels and transiently increased horseradish peroxidase permeability in ATB offspring colon were observed. Importantly, long-term consequences included reduced colonic horseradish peroxidase permeability, and increased colonic digesta alkaline phosphatase (AP and TLR2- and TLR4-stimulant concentrations in rectal digesta in adult ATB offspring. Inducible HSP27 and HSP70 did not change. Interactions between early ATB treatment and later diet were noted for paracellular permeability and concentrations of colonic

Mechanisms linking dietary fiber, gut microbiota and colon cancer prevention.

Science.gov (United States)

Zeng, Huawei; Lazarova, Darina L; Bordonaro, Michael

2014-02-15

Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carcinogens within the intestinal lumen and to promote healthy gut microbiota, which modifies the host's metabolism in various ways. Elucidation of the mechanisms by which dietary fiber-dependent changes in gut microbiota enhance bile acid deconjugation, produce short chain fatty acids, and modulate inflammatory bioactive substances can lead to a better understanding of the beneficial role of dietary fiber. This article reviews the current knowledge concerning the mechanisms via which dietary fiber protects against colon cancer.

The influence of simple sugars and starch given during pre- or post-initiation on aberrant crypt foci in rat colon

DEFF Research Database (Denmark)

Poulsen, Morten; Mølck, Anne-Marie; Thorup, Inger

2001-01-01

The aim of the present study was to investigate the enhancing effect of dietary sugar on the development of aberrant crypt foci (ACF) in male F344 rats initiated with azoxymethane (AOM). The potential role of sugar as either a co-initiator or a promoter was investigated by giving diets high...... in sucrose and dextrin (61%) during either the pre-initiation, the initiation, and/or the post initiation stage of the ACF development. The colonic cell proliferation, activity of colonic phase II enzymes, and a biomarker of lipid peroxidation were additionally examined in order to obtain information...... on the specific mechanisms involved in the suggested effect of sucrose and dextrin on ACF development. The number of large sized and the total number of ACF were significantly increased by feeding sucrose and dextrin in the post-initiation period. No positive association between colonic cell proliferation and ACF...

Glucosinolates from pak choi and broccoli induce enzymes and inhibit inflammation and colon cancer differently.

Science.gov (United States)

Lippmann, Doris; Lehmann, Carsten; Florian, Simone; Barknowitz, Gitte; Haack, Michael; Mewis, Inga; Wiesner, Melanie; Schreiner, Monika; Glatt, Hansruedi; Brigelius-Flohé, Regina; Kipp, Anna P

2014-06-01

High consumption of Brassica vegetables is considered to prevent especially colon carcinogenesis. The content and pattern of glucosinolates (GSLs) can highly vary among different Brassica vegetables and may, thus, affect the outcome of Brassica intervention studies. Therefore, we aimed to feed mice with diets containing plant materials of the Brassica vegetables broccoli and pak choi. Further enrichment of the diets by adding GSL extracts allowed us to analyze the impact of different amounts (GSL-poor versus GSL-rich) and different patterns (broccoli versus pak choi) of GSLs on inflammation and tumor development in a model of inflammation-triggered colon carcinogenesis (AOM/DSS model). Serum albumin adducts were analyzed to confirm the up-take and bioactivation of GSLs after feeding the Brassica diets for four weeks. In agreement with their high glucoraphanin content, broccoli diets induced the formation of sulforaphane-lysine adducts. Levels of 1-methoxyindolyl-3-methyl-histidine adducts derived from neoglucobrassicin were the highest in the GSL-rich pak choi group. In the colon, the GSL-rich broccoli and the GSL-rich pak choi diet up-regulated the expression of different sets of typical Nrf2 target genes like Nqo1, Gstm1, Srxn1, and GPx2. GSL-rich pak choi induced the AhR target gene Cyp1a1 but did not affect Ugt1a1 expression. Both colitis and tumor number were drastically reduced after feeding the GSL-rich pak choi diet while the other three diets had no effect. GSLs can act anti-inflammatory and anti-carcinogenic but both effects depend on the specific amount and pattern of GSLs within a vegetable. Thus, a high Brassica consumption cannot be generally considered to be cancer-preventive.

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.

Voluntary exercise inhibits intestinal tumorigenesis in ApcMin/+ mice and azoxymethane/dextran sulfate sodium-treated mice

International Nuclear Information System (INIS)

Ju, Jihyeung; Nolan, Bonnie; Cheh, Michelle; Bose, Mousumi; Lin, Yong; Wagner, George C; Yang, Chung S

2008-01-01

Epidemiological studies suggest that physical activity reduces the risk of colon cancer in humans. Results from animal studies, however, are inconclusive. The present study investigated the effects of voluntary exercise on intestinal tumor formation in two different animal models, Apc Min/+ mice and azoxymethane (AOM)/dextran sulfate sodium (DSS)-treated mice. In Experiments 1 and 2, five-week old female Apc Min/+ mice were either housed in regular cages or cages equipped with a running wheel for 6 weeks (for mice maintained on the AIN93G diet; Experiment 1) or 9 weeks (for mice on a high-fat diet; Experiment 2). In Experiment 3, male CF-1 mice at 6 weeks of age were given a dose of AOM (10 mg/kg body weight, i.p.) and, 12 days later, 1.5% DSS in drinking fluid for 1 week. The mice were then maintained on a high-fat diet and housed in regular cages or cages equipped with a running wheel for 16 weeks. In the Apc Min/+ mice maintained on either the AIN93G or the high-fat diet, voluntary exercise decreased the number of small intestinal tumors. In the AOM/DSS-treated mice maintained on a high-fat diet, voluntary exercise also decreased the number of colon tumors. In Apc Min/+ mice, voluntary exercise decreased the ratio of serum insulin like growth factor (IGF)-1 to IGF binding protein (BP)-3 levels. It also decreased prostaglandin E 2 and nuclear β-catenin levels, but increased E-cadherin levels in the tumors. These results indicate hat voluntary exercise inhibited intestinal tumorigenesis in Apc Min/+ mice and AOM/DSS-treated mice, and the inhibitory effect is associated with decreased IGF-1/IGFBP-3 ratio, aberrant β-catenin signaling, and arachidonic acid metabolism

[Dietary prevention and treatment of diverticular disease of the colon].

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Milewska, Magdalena; Sińska, Beata; Kluciński, Andrzej

2015-04-01

Diverticular disease is more often categorized as a civilization disease that affects both women and men, especially at an old age. The pathophysiology remains complex and arises from the interaction between dietary fiber intake, bowel motility and mucosal changes in the colon. Obesity, smoking, low physical activity, low-fiber diet (poor in vegetables, fruit, whole grain products, seeds and nuts) are among factors that increase the risk for developing diverticular disease. Additionally, the colonic outpouchings may be influenced by involutional changes of the gastrointestinal tract. Therefore, the fiber rich diet (25-40 g/day) plays an important role in prevention, as well as nonpharmacological treatment of uncomplicated diverticular disease. The successful goal of the therapy can be achieved by well-balanced diet or fiber supplements intake. Research indicate the effectiveness of probiotics in dietary management during the remission process. Moreover, drinking of appropriate water amount and excluding from the diet products decreasing colonic transit time - should be also applied. © 2015 MEDPRESS.

A modified R-type bacteriocin specifically targeting Clostridium difficile prevents colonization of mice without affecting gut microbiota diversity.

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Gebhart, Dana; Lok, Stephen; Clare, Simon; Tomas, Myreen; Stares, Mark; Scholl, Dean; Donskey, Curtis J; Lawley, Trevor D; Govoni, Gregory R

2015-03-24

Clostridium difficile is a leading cause of nosocomial infections worldwide and has become an urgent public health threat requiring immediate attention. Epidemic lineages of the BI/NAP1/027 strain type have emerged and spread through health care systems across the globe over the past decade. Limiting person-to-person transmission and eradicating C. difficile, especially the BI/NAP1/027 strain type, from health care facilities are difficult due to the abundant shedding of spores that are impervious to most interventions. Effective prophylaxis for C. difficile infection (CDI) is lacking. We have genetically modified a contractile R-type bacteriocin ("diffocin") from C. difficile strain CD4 to kill BI/NAP1/027-type strains for this purpose. The natural receptor binding protein (RBP) responsible for diffocin targeting was replaced with a newly discovered RBP identified within a prophage of a BI/NAP1/027-type target strain by genome mining. The resulting modified diffocins (a.k.a. Avidocin-CDs), Av-CD291.1 and Av-CD291.2, were stable and killed all 16 tested BI/NAP1/027-type strains. Av-CD291.2 administered in drinking water survived passage through the mouse gastrointestinal (GI) tract, did not detectably alter the mouse gut microbiota or disrupt natural colonization resistance to C. difficile or the vancomycin-resistant Enterococcus faecium (VREF), and prevented antibiotic-induced colonization of mice inoculated with BI/NAP1/027-type spores. Given the high incidence and virulence of the pathogen, preventing colonization by BI/NAP1/027-type strains and limiting their transmission could significantly reduce the occurrence of the most severe CDIs. This modified diffocin represents a prototype of an Avidocin-CD platform capable of producing targetable, precision anti-C. difficile agents that can prevent and potentially treat CDIs without disrupting protective indigenous microbiota. Treatment and prevention strategies for bacterial diseases rely heavily on traditional

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.

Capecitabine treatment of HCT-15 colon cancer cells induces ...

African Journals Online (AJOL)

HCT-15 cells caused condensation of DNA and induced apoptosis in a concentration- ... Conclusion: Capecitabine treatment causes inhibition of colon cancer growth via the mitochondrial ... fluoropyrimidine aimed to selectively transfer 5-.

Changes in colonic motility induced by sennosides in dogs: evidence of a prostaglandin mediation.

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Staumont, G; Fioramonti, J; Frexinos, J; Bueno, L

1988-01-01

The effects of sennosides on colonic motility were investigated in eight conscious dogs chronically fitted with two strain gauge transducers in the proximal colon, an intracolonic silicone catheter and a polyethylene catheter implanted in a branch of the right colonic artery. Oral sennosides (30 mg/kg) inhibited colonic motility for 12 to 18 h after a three to six hours delay, and associated with giant contractions and diarrhoea. The minimal oral dose of sennosides to produce such changes varied from 5 to 15 mg/kg. Intracolonic sennosides at the minimal effective dose and at 30 mg/kg reproduced the effects of oral sennosides, but with a shorter latency (0.5-1.5 h). Intracolonic PGE2 (100 micrograms/kg) in viscous gel medium or intra-arterial PGE2 (10 micrograms/h) inhibited colonic motility and induced giant contractions often associated with defecation. The colonic motor changes induced by intracolonic sennosides at the minimal effective dose, but not those induced by intracolonic PGE2, were blocked by intra-arterial indomethacin (10 micrograms/h) or piroxicam (5 micrograms/h). These results suggest that colonic motor actions of sennosides are mediated through a local prostaglandins synthesis, as they were blocked by cyclooxygenase inhibitor and reproduced by PGE2. PMID:3197991

Calreticulin is a fine tuning molecule in epibrassinolide-induced apoptosis through activating endoplasmic reticulum stress in colon cancer cells.

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Obakan-Yerlikaya, Pinar; Arisan, Elif Damla; Coker-Gurkan, Ajda; Adacan, Kaan; Ozbey, Utku; Somuncu, Berna; Baran, Didem; Palavan-Unsal, Narcin

2017-06-01

Epibrassinolide (EBR), a member of brassinostreoids plant hormones with cell proliferation promoting role in plants, is a natural polyhydroxysteroid with structural similarity to steroid hormones of vertebrates. EBR has antiproliferative and apoptosis-inducing effect in various cancer cells. Although EBR has been shown to affect survival and mitochondria-mediated apoptosis pathways in a p53-independent manner, the exact molecular targets of EBR are still under investigation. Our recent SILAC (Stable Isotope Labeling by Amino Acids in Cell Culture) data showed that the most significantly altered protein after EBR treatment was calreticulin (CALR). CALR, a chaperone localized in endoplasmic reticulum (ER) lumen, plays role in protein folding and buffering Ca 2+ ions. The alteration of CALR may cause ER stress and unfolded protein response correspondingly the induction of apoptosis. Unfolded proteins are conducted to 26S proteasomal degradation following ubiquitination. Our study revealed that EBR treatment caused ER stress and UPR by altering CALR expression causing caspase-dependent apoptosis in HCT 116, HT29, DLD-1, and SW480 colon cancer cells. Furthermore, 48 h EBR treatment did not caused UPR in Fetal Human Colon cells (FHC) and Mouse Embryonic Fibroblast cells (MEF). In addition our findings showed that HCT 116 colon cancer cells lacking Bax and Puma expression still undergo UPR and related apoptosis. CALR silencing and rapamycin co-treatment prevented EBR-induced UPR and apoptosis, whereas 26S proteasome inhibition further increased the effect of EBR in colon cancer cells. All these findings showed that EBR is an ER stress and apoptotic inducer in colon cancer cells without affecting non-malignant cells. © 2017 Wiley Periodicals, Inc.

Dietary Selenium Deficiency Exacerbates DSS-Induced Epithelial Injury and AOM/DSS-Induced Tumorigenesis

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Barrett, Caitlyn W.; Singh, Kshipra; Motley, Amy K.; Lintel, Mary K.; Matafonova, Elena; Bradley, Amber M.; Ning, Wei; Poindexter, Shenika V.; Parang, Bobak; Reddy, Vishruth K.; Chaturvedi, Rupesh; Fingleton, Barbara M.; Washington, Mary K.; Wilson, Keith T.; Davies, Sean S.; Hill, Kristina E.; Burk, Raymond F.; Williams, Christopher S.

2013-01-01

Selenium (Se) is an essential micronutrient that exerts its functions via selenoproteins. Little is known about the role of Se in inflammatory bowel disease (IBD). Epidemiological studies have inversely correlated nutritional Se status with IBD severity and colon cancer risk. Moreover, molecular studies have revealed that Se deficiency activates WNT signaling, a pathway essential to intestinal stem cell programs and pivotal to injury recovery processes in IBD that is also activated in inflammatory neoplastic transformation. In order to better understand the role of Se in epithelial injury and tumorigenesis resulting from inflammatory stimuli, we examined colonic phenotypes in Se-deficient or -sufficient mice in response to dextran sodium sulfate (DSS)-induced colitis, and azoxymethane (AOM) followed by cyclical administration of DSS, respectively. In response to DSS alone, Se-deficient mice demonstrated increased morbidity, weight loss, stool scores, and colonic injury with a concomitant increase in DNA damage and increases in inflammation-related cytokines. As there was an increase in DNA damage as well as expression of several EGF and TGF-β pathway genes in response to inflammatory injury, we sought to determine if tumorigenesis was altered in the setting of inflammatory carcinogenesis. Se-deficient mice subjected to AOM/DSS treatment to model colitis-associated cancer (CAC) had increased tumor number, though not size, as well as increased incidence of high grade dysplasia. This increase in tumor initiation was likely due to a general increase in colonic DNA damage, as increased 8-OHdG staining was seen in Se-deficient tumors and adjacent, non-tumor mucosa. Taken together, our results indicate that Se deficiency worsens experimental colitis and promotes tumor development and progression in inflammatory carcinogenesis. PMID:23861820

Adrenaline-induced colonic K+ secretion is mediated by KCa1.1 (BK) channels

DEFF Research Database (Denmark)

Sørensen, Mads Vaarby; Sausbier, Matthias; Ruth, Peter

2010-01-01

. However, the secretory K(+) channel responsible for cAMP-induced K(+) secretion remains to be defined. In this study we used the Ussing chamber to identify adrenaline-induced electrogenic K(+) secretion. We found that the adrenaline-induced electrogenic ion secretion is a compound effect dominated...... variants in colonic enterocytes (STREX and ZERO). Importantly, the ZERO variant known to be activated by cAMP is differentially up-regulated in enterocytes from animals on a high K(+) diet. In summary, these results strongly suggest that the adrenaline-induced distal colonic K(+) secretion is mediated...

Methyl Sartortuoate Inhibits Colon Cancer Cell Growth by Inducing Apoptosis and G2/M-Phase Arrest.

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Lan, Qiusheng; Li, Shoufeng; Lai, Wei; Xu, Heyang; Zhang, Yang; Zeng, Yujie; Lan, Wenjian; Chu, Zhonghua

2015-08-17

The potential anti-neoplastic activity of terpenoids is of continued interest. In this study, we investigate whether methyl sartortuoate, a terpenoid isolated from soft coral, induced cell cycle arrest and apoptosis in a human colon cancer cell line. Culture studies found that methyl sartortuoate inhibited colon cancer cell (LoVo and RKO) growth and caused apoptotic death in a concentration- and time-dependent manner, by activation of caspase-8, caspase-9, caspase-3, p53 and Bax, and inactivation of B-cell lymphoma 2 (Bcl-2) apoptosis regulating proteins. Methyl sartortuoate treatment led to reduced expression of cdc2 and up-regulated p21 and p53, suggesting that Methyl sartortuoate induced G2-M arrest through modulation of p53/p21/cdc2 pathways. Methyl sartortuoate also up-regulated phospho-JNK and phospho-p38 expression levels. This resulted in cell cycle arrest at the G2-M phase and apoptosis in LoVo and RKO cells. Treatment with the JNK inhibitor SP600125 and the p38 MAPK inhibitor SB203580 prevented methyl sartortuoate-induced apoptosis in LoVo cells. Moreover, methyl sartortuoate also prevented neoplasm growth in NOD-SCID nude mice inoculated with LoVo cells. Taken together, these findings suggest that methyl sartortuoate is capable of leading to activation of caspase-8, -9, -3, increasing p53 and Bax/Bcl-2 ratio apoptosis through MAPK-dependent apoptosis and results in G2-M phase arrest in LoVo and RKO cells. Thus, methyl sartortuoate may be a promising anticancer candidate.

Optical coherence tomography imaging of colonic crypts in a mouse model of colorectal cancer

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Welge, Weston A.; Barton, Jennifer K.

2016-03-01

Aberrant crypt foci (ACF) are abnormal epithelial lesions that precede development of colonic polyps. As the earliest morphological change in the development of colorectal cancer, ACF is a highly studied phenomenon. The most common method of imaging ACF is chromoendoscopy using methylene blue as a contrast agent. Narrow- band imaging is a contrast-agent-free modality for imaging the colonic crypts. Optical coherence tomography (OCT) is an attractive alternative to chromoendoscopy and narrow-band imaging because it can resolve the crypt structure at sufficiently high sampling while simultaneously providing depth-resolved data. We imaged in vivo the distal 15 mm of colon in the azoxymethane (AOM) mouse model of colorectal cancer using a commercial swept-source OCT system and a miniature endoscope designed and built in-house. We present en face images of the colonic crypts and demonstrate that different patterns in healthy and adenoma tissue can be seen. These patterns correspond to those reported in the literature. We have previously demonstrated early detection of colon adenoma using OCT by detecting minute thickening of the mucosa. By combining mucosal thickness measurement with imaging of the crypt structure, OCT can be used to correlate ACF and adenoma development in space and time. These results suggest that OCT may be a superior imaging modality for studying the connection between ACF and colorectal cancer.

Phenolic extract from oleaster (Olea europaea var. Sylvestris) leaves reduces colon cancer growth and induces caspase-dependent apoptosis in colon cancer cells via the mitochondrial apoptotic pathway.

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Zeriouh, Wafa; Nani, Abdelhafid; Belarbi, Meriem; Dumont, Adélie; de Rosny, Charlotte; Aboura, Ikram; Ghanemi, Fatima Zahra; Murtaza, Babar; Patoli, Danish; Thomas, Charles; Apetoh, Lionel; Rébé, Cédric; Delmas, Dominique; Khan, Naim Akhtar; Ghiringhelli, François; Rialland, Mickael; Hichami, Aziz

2017-01-01

Dietary polyphenols, derived from natural products, have received a great interest for their chemopreventive properties against cancer. In this study, we investigated the effects of phenolic extract of the oleaster leaves (PEOL) on tumor growth in mouse model and on cell death in colon cancer cell lines. We assessed the effect of oleaster leaf infusion on HCT116 (human colon cancer cell line) xenograft growth in athymic nude mice. We observed that oleaster leaf polyphenol-rich infusion limited HCT116 tumor growth in vivo. Investigations of PEOL on two human CRC cell lines showed that PEOL induced apoptosis in HCT116 and HCT8 cells. We demonstrated an activation of caspase-3, -7 and -9 by PEOL and that pre-treatment with the pan-caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), prevented PEOL-induced cell death. We observed an involvement of the mitochondrial pathway in PEOL-induced apoptosis evidenced by reactive oxygen species (ROS) production, a decrease of mitochondrial membrane potential, and cytochrome c release. Increase in intracellular Ca2+ concentration induced by PEOL represents the early event involved in mitochondrial dysfunction, ROS-induced endoplasmic reticulum (ER) stress and apoptosis induced by PEOL, as ruthenium red, an inhibitor of mitochondrial calcium uptake inhibited apoptotic effect of PEOL, BAPTA/AM inhibited PEOL-induced ROS generation and finally, N-acetyl-L-cysteine reversed ER stress and apoptotic effect of PEOL. These results demonstrate that polyphenols from oleaster leaves might have a strong potential as chemopreventive agent in colorectal cancer.

Induced terpene accumulation in Norway spruce inhibits bark beetle colonization in a dose-dependent manner.

Directory of Open Access Journals (Sweden)

Tao Zhao

Full Text Available Tree-killing bark beetles (Coleoptera, Scolytinae are among the most economically and ecologically important forest pests in the northern hemisphere. Induction of terpenoid-based oleoresin has long been considered important in conifer defense against bark beetles, but it has been difficult to demonstrate a direct correlation between terpene levels and resistance to bark beetle colonization.To test for inhibitory effects of induced terpenes on colonization by the spruce bark beetle Ips typographus (L. we inoculated 20 mature Norway spruce Picea abies (L. Karsten trees with a virulent fungus associated with the beetle, Ceratocystis polonica (Siem. C. Moreau, and investigated induced terpene levels and beetle colonization in the bark.Fungal inoculation induced very strong and highly variable terpene accumulation 35 days after inoculation. Trees with high induced terpene levels (n = 7 had only 4.9% as many beetle attacks (5.1 vs. 103.5 attacks m(-2 and 2.6% as much gallery length (0.029 m m(-2 vs. 1.11 m m(-2 as trees with low terpene levels (n = 6. There was a highly significant rank correlation between terpene levels at day 35 and beetle colonization in individual trees. The relationship between induced terpene levels and beetle colonization was not linear but thresholded: above a low threshold concentration of ∼100 mg terpene g(-1 dry phloem trees suffered only moderate beetle colonization, and above a high threshold of ∼200 mg terpene g(-1 dry phloem trees were virtually unattacked.This is the first study demonstrating a dose-dependent relationship between induced terpenes and tree resistance to bark beetle colonization under field conditions, indicating that terpene induction may be instrumental in tree resistance. This knowledge could be useful for developing management strategies that decrease the impact of tree-killing bark beetles.

α-fetoprotein involvement during glucocorticoid-induced precocious maturation in rat colon.

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Chen, Min; Sun, Peng; Liu, Xiao-Yan; Dong, Dan; Du, Jun; Gu, Luo; Ge, Ying-Bin

2011-06-28

To investigate the role of α-fetoprotein (AFP), a cancer-associated fetal glycoprotein, in glucocorticoid-induced precocious maturation in rat colon. Colons from suckling Sprague-Dawley rats were used in this study. Corticosterone acetate at a dose of 100 μg/g body weight was given to normal pups on days 7, 9 and 11 after birth to induce hypercorticoidism. Control animals were injected with identical volumes of normal saline. Some rats receiving corticosterone 7 d after birth were also treated with mifepristone (RU38486), a glucocorticoid cytoplasm receptor antagonist to investigate the effects of glucocorticoids (GCs). The morphological changes of the crypt depth and villous height of the villous zone in colon were observed as indices of colon maturation. Expression levels of AFP in colons were detected by reverse transcriptase polymerase chain reaction and Western blotting. To identify the cellular localization of AFP in developing rat colons, double-immunofluorescent staining was performed using antibodies to specific mesenchymal cell marker and AFP. Corticosterone increased the crypt depth and villous height in the colon of 8- and 10-d-old rats with hypercorticoidism compared with that in the control animals (120% in 8-d-old rats and 118% in 10-d-old rats in villous height, P = 0.021; 145% in 8-d-old rats and 124% in 10-d-old rats in crypt depth, P = 0.017). These increases were accompanied by an increase of AFP expression in both mRNA and protein (2.5-folds in 8-d-old and 2.5-folds in 10-d-old rats higher than in control animals, P = 0.035; 1.8-folds in 8-d-old and 1.3-folds in 10-d-old rats higher than in control animals, P = 0.023). Increased crypt depth and villous height and increased expression of AFP in the colon of rats with hypercorticoidism were blocked by mifepristone. Both had positive staining for AFP or vimentin, and overlapped in mesenchymal cells at each tested colon. GCs promote the development of rat colon. AFP appears to be involved, in

HMG-CoA reductase regulates CCL17-induced colon cancer cell migration via geranylgeranylation and RhoA activation

International Nuclear Information System (INIS)

Al-Haidari, Amr A.; Syk, Ingvar; Thorlacius, Henrik

2014-01-01

Highlights: • Simvastatin blocked CCL17-induced and CCR4-dependent RhoA activation in HT29 cells. • CCL17/CCR4-mediated migration of colon cancer cells was antagonised by simvastatin. • Cell migration recovered by adding Mevalonate and geranylgeranyl pyrophosphate. • Targeting HMG-CoA reductase might be useful to inhibit colon cancer metastasis. - Abstract: Background: Simvastatin is widely used to lower cholesterol levels in patients with cardiovascular diseases, although accumulating evidence suggests that statins, such as simvastatin, also exert numerous anti-tumoral effects. Aim: The aim of this study was to examine the effect of simvastatin on colon cancer cell migration. Methods: Migration assays were performed to evaluate CCL17-induced colon cancer cell (HT-29) chemotaxis. In vitro tumor growth and apoptosis were assessed using a proliferation assay and annexin V assay, respectively. Active RhoA protein levels in CCL17-stimulated colon cancer cells were quantified using a G-LISA assay. Results: We found that simvastatin dose-dependently decreased CCL17-induced colon cancer cell migration. Simvastatin had no effect on colon cancer cell proliferation or apoptosis. Inhibition of beta chemokine receptor 4, CCR4, reduced CCL17-evoked activation of RhoA in colon cancer cells. Moreover, administration of mevalonate reversed the inhibitory effect of simvastatin on CCL17-induced colon cancer cell migration. Interestingly, co-incubation with geranylgeranyl pyrophosphate (GGPP) antagonized the inhibitory impact of simvastatin on colon cancer cell migration triggered by CCL17. Moreover, we observed that simvastatin decreased CCL17-induced activation of RhoA in colon cancer cells. Administration of mevalonate and GGPP reversed the inhibitory effect of simvastatin on CCL17-provoked RhoA activation in colon cancer cells. Conclusions: Taken together, our findings show for the first time that HMG-CoA reductase regulates CCL17-induced colon cancer cell migration via

Effects of Lactobacillus salivarius Ren on cancer prevention and intestinal microbiota in 1, 2-dimethylhydrazine-induced rat model.

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Zhang, Ming; Fan, Xing; Fang, Bing; Zhu, Chengzhen; Zhu, Jun; Ren, Fazheng

2015-06-01

Probiotics have been suggested as a prophylactic measure in colon cancer. The aim of this study was to investigate the impact of Lactobacillus salivarius Ren (Ren) in modulating colonic microbiota structure and colon cancer incidence in a rat model after injection with 1,2-dimethyl hydrazine (DMH). The results indicated that oral administration of Ren could effectively suppress DMH-induced colonic carcinogenesis. A significant decrease in cancer incidence (87.5% to 25%) was detected in rats fed with a dose of 5 × 10(10) CFU/kg bodyweight per day. Using denaturing gradient gel electrophoresis and Real-time PCR combined with multivariate statistical methods, we demonstrated that injection with DMH significantly altered the rat gut microbiota, while Ren counteracted these DMH-induced adverse effects and promoted reversion of the gut microbiota close to the healthy state. Tvalue biplots followed by band sequencing identified 21 bacterial strains as critical variables affected by DMH and Ren. Injection of DMH significantly increased the amount of Ruminococcus species (sp.) and Clostridiales bacteria, as well as decreasing the Prevotella sp. Administration of Ren reduced the amount of Ruminococcus sp., Clostridiales bacteria, and Bacteroides dorei, and increased the amount of Prevotella. Real-time PCR results were consistent with the results derived by t-value biplots. These findings suggested that Ren is a potential agent for colon cancer prevention. In conclusion, the results in the present study suggest a potential therapeutic approach based on the modulation of intestinal microflora by probiotics may be beneficial in the prevention of colorectal carcinogenesis.

Bilirubin prevents acute DSS-induced colitis by inhibiting leukocyte infiltration and suppressing upregulation of inducible nitric oxide synthase.

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Zucker, Stephen D; Vogel, Megan E; Kindel, Tammy L; Smith, Darcey L H; Idelman, Gila; Avissar, Uri; Kakarlapudi, Ganesh; Masnovi, Michelle E

2015-11-15

Bilirubin is thought to exert anti-inflammatory effects by inhibiting vascular cell adhesion molecule-1 (VCAM-1)-dependent leukocyte migration and by suppressing the expression of inducible nitric oxide synthase (iNOS). As VCAM-1 and iNOS are important mediators of tissue injury in the dextran sodium sulfate (DSS) murine model of inflammatory colitis, we examined whether bilirubin prevents colonic injury in DSS-treated mice. Male C57BL/6 mice were administered 2.5% DSS in the drinking water for 7 days, while simultaneously receiving intraperitoneal injections of bilirubin (30 mg/kg) or potassium phosphate vehicle. Disease activity was monitored, peripheral blood counts and serum nitrate levels were determined, and intestinal specimens were analyzed for histological injury, leukocyte infiltration, and iNOS expression. The effect of bilirubin on IL-5 production by HSB-2 cells and on Jurkat cell transendothelial migration also was determined. DSS-treated mice that simultaneously received bilirubin lost less body weight, had lower serum nitrate levels, and exhibited reduced disease severity than vehicle-treated animals. Concordantly, histopathological analyses revealed that bilirubin-treated mice manifested significantly less colonic injury, including reduced infiltration of eosinophils, lymphocytes, and monocytes, and diminished iNOS expression. Bilirubin administration also was associated with decreased eosinophil and monocyte infiltration into the small intestine, with a corresponding increase in peripheral blood eosinophilia. Bilirubin prevented Jurkat migration but did not alter IL-5 production. In conclusion, bilirubin prevents DSS-induced colitis by inhibiting the migration of leukocytes across the vascular endothelium and by suppressing iNOS expression. Copyright © 2015 the American Physiological Society.

Chemopreventive effect of artesunate in 1,2-dimethylhydrazine-induced rat colon carcinogenesis

Directory of Open Access Journals (Sweden)

Sazal Patyar

2017-01-01

Full Text Available Artesunate (ART is a semisynthetic derivative of artemisinin. Artemisinin and its derivatives have shown profound cytotoxicity and antitumor activity in addition to antimalarial activity in various studies. As the in vivo chemopreventive efficacy of ART in colon carcinogenesis has not been investigated so far, the aim of the current study was to study the chemopreventive effect of ART in 1,2-dimethylhydrazine (DMH-induced rat colon carcinogenesis. Animals were divided into four groups (n = 6: Group I - vehicle (1 mM ethylenediaminetetraacetic acid, Group II - DMH (20 mg/kg, Group III - DMH + 5-fluorouracil (81 mg/kg, Group IV - DMH + ART (6.7 mg/kg. After completion of 15 weeks of treatment, rats were sacrificed under ether anesthesia by cervical dislocation for assessment of lipid peroxidation (LPO, antioxidant status, average number of aberrant crypt foci (ACF, and cytokine levels. ART administration significantly decreased the average number of ACF/microscopic field. Similarly, LPO level was decreased and antioxidant activities were enhanced after ART treatment. ART decreased the levels of proinflammatory cytokines and induced apoptosis in the colons of DMH-treated rats. The results of this study suggest that ART has a beneficial effect against chemically induced colonic preneoplastic progression in rats.

Curcumin and salsalate suppresses colonic inflammation and procarcinogenic signaling in high-fat-fed, azoxymethane-treated mice

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High-fat diets (HFDs) and excess adiposity increase proinflammatory cytokines in the colon, altering gene expression in a manner that promotes the development of colorectal cancer (CRC). Thus, compounds that reduce this biochemical inflammation are potential chemopreventive agents. Curcumin (CUR), a...

Obesity-related colon cancer: dietary factors and their mechanisms of anticancer action.

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Zeng, Huawei; Lazarova, Darina L

2012-02-01

Overweight/obesity is an epidemic in the US as well as in other developed countries, affecting two-thirds of Americans and an estimated 2.3 billion people worldwide. Obesity increases the risk for Type 2 diabetes, cardiovascular disease and cancer. For example, epidemiological studies have established a strong association between obesity and colon cancer. It is generally accepted that metabolic changes associated with overweight/obesity, particularly abdominal obesity and changes in adipocyte function, contribute to the increased risk of colon cancer. Understanding the mechanisms underlying this association is important for the development of preventive strategies for colon cancer. Part of these preventive strategies may be based on dietary factors, such as vitamins, minerals (e.g. selenium), fibre, phytochemicals and phenolic compounds. These anticancer nutrients may counteract the molecular changes associated with obesity. The present article reviews the evidence that inflammation and insulin resistance induced by obesity are the molecular mediators of the association between obesity and colon cancer. We also evaluate the evidence for the ability of dietary factors to target the obesity-induced changes and, thus, protect against colon cancer. © 2011 The Authors. Clinical and Experimental Pharmacology and Physiology © 2011 Blackwell Publishing Asia Pty Ltd.

Rice bran phytochemicals and dietary colon chemoprevention teamwork

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A growing body of evidence supports that dietary rice bran exhibits gastrointestinal cancer control and prevention activity using carcinogen induced animal models and human colon cancer cell lines. Our laboratory has recently reported metabolomic differences in rice from globally and genetically dis...

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

Science.gov (United States)

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.

Hypoxia-inducible factor-1α induces multidrug resistance protein in colon cancer

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Lv Y

2015-07-01

Full Text Available Yingqian Lv, Shan Zhao, Jinzhu Han, Likang Zheng, Zixin Yang, Li Zhao Department of Oncology, The Second Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, People’s Republic of China Abstract: Multidrug resistance is the major cause of chemotherapy failure in many solid tumors, including colon cancer. Hypoxic environment is a feature for all solid tumors and is important for the development of tumor resistance to chemotherapy. Hypoxia-inducible factor (HIF-1α is the key transcription factor that mediates cellular response to hypoxia. HIF-1α has been shown to play an important role in tumor resistance; however, the mechanism is still not fully understood. Here, we found that HIF-1α and the drug resistance-associated gene multidrug resistance associated protein 1 (MRP1 were induced by treatment of colon cancer cells with the hypoxia-mimetic agent cobalt chloride. Inhibition of HIF-1α by RNA interference and dominant-negative protein can significantly reduce the induction of MRP1 by hypoxia. Bioinformatics analysis showed that a hypoxia response element is located at -378 to -373 bp upstream of the transcription start site of MRP1 gene. Luciferase reporter assay combined with mutation analysis confirmed that this element is essential for hypoxia-mediated activation of MRP gene. Furthermore, RNA interference revealed that HIF-1α is necessary for this hypoxia-driven activation of MRP1 promoter. Importantly, chromatin immunoprecipitation analysis demonstrated that HIF-1α could directly bind to this HRE site in vivo. Together, these data suggest that MRP1 is a downstream target gene of HIF-1α, which provides a potential novel mechanism for HIF-1α-mediated drug resistance in colon cancer and maybe other solid tumors as well. Keywords: hypoxia, hypoxia-inducible factor-1α, multidrug resistance associated protein, transcriptional regulation, chemotherapy tolerance

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

Recent advances in the treatment of colonic diverticular disease and prevention of acute diverticulitis

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Elisei, Walter; Tursi, Antonio

2016-01-01

The incidence of diverticulosis and diverticular disease of the colon is increasing worldwide. Although the majority of patients remains asymptomatic long-life, the prevalence of diverticular disease of the colon, including acute diverticulitis, is substantial and is becoming a significant burden on National Health Systems in terms of direct and indirect costs. Focus is now being drawn on identifying the correct therapeutic approach by testing various treatments. Fiber, non-absorbable antibiotics and probiotics seem to be effective in treating symptomatic and uncomplicated patients, and 5-aminosalicylic acid might help prevent acute diverticulitis. Unfortunately, robust evidence on the effectiveness of a medical strategy to prevent acute diverticulitis recurrence is still lacking. We herein provide a concise review on the effectiveness and future perspectives of these treatments. PMID:26752946

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.

CALCIUM AND THE PREVENTION OF COLON CANCER

NARCIS (Netherlands)

WELBERG, JWM; KLEIBEUKER, JH; VANDERMEER, R; MULDER, NH; DEVRIES, EGE

1991-01-01

Diet is a major determinant of colon cancer risk. Calcium may protect against colon cancer, presumably by binding cytotoxic bile acids and fatty acids. Numerous studies support this proposition. In subjects at risk for colon cancer oral calcium supplementation has been shown to reduce rectal

Loss of claudin-3 expression induces IL6/gp130/Stat3 signaling to promote colon cancer malignancy by hyperactivating Wnt/β-catenin signaling.

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Ahmad, R; Kumar, B; Chen, Z; Chen, X; Müller, D; Lele, S M; Washington, M K; Batra, S K; Dhawan, P; Singh, A B

2017-11-23

The hyperactivated Wnt/β-catenin signaling acts as a switch to induce epithelial to mesenchymal transition and promote colorectal cancer. However, due to its essential role in gut homeostasis, therapeutic targeting of this pathway has proven challenging. Additionally, IL-6/Stat-3 signaling, activated by microbial translocation through the dysregulated mucosal barrier in colon adenomas, facilitates the adenoma to adenocarcinomas transition. However, inter-dependence between these signaling pathways and key mucosal barrier components in regulating colon tumorigenesis and cancer progression remains unclear. In current study, we have discovered, using a comprehensive investigative regimen, a novel and tissue-specific role of claudin-3, a tight junction integral protein, in inhibiting colon cancer progression by serving as the common rheostat of Stat-3 and Wnt-signaling activation. Loss of claudin-3 also predicted poor patient survival. These findings however contrasted an upregulated claudin-3 expression in other cancer types and implicated role of the epigenetic regulation. Claudin-3-/- mice revealed dedifferentiated and leaky colonic epithelium, and developed invasive adenocarcinoma when subjected to colon cancer. Wnt-signaling hyperactivation, albeit in GSK-3β independent manner, differentiated colon cancer in claudin-3-/- mice versus WT-mice. Claudin-3 loss also upregulated the gp130/IL6/Stat3 signaling in colonic epithelium potentially assisted by infiltrating immune components. Genetic and pharmacological studies confirmed that claudin-3 loss induces Wnt/β-catenin activation, which is further exacerbated by Stat-3-activation and help promote colon cancer. Overall, these novel findings identify claudin-3 as a therapeutic target for inhibiting overactivation of Wnt-signaling to prevent CRC malignancy.

Dysregulation of microRNAs in colonic field carcinogenesis: implications for screening.

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Dhananjay P Kunte

Full Text Available Colorectal cancer (CRC screening tests often have a trade-off between efficacy and patient acceptability/cost. Fecal tests (occult blood, methylation engender excellent patient compliance but lack requisite performance underscoring the need for better population screening tests. We assessed the utility of microRNAs (miRNAs as markers of field carcinogenesis and their potential role for CRC screening using the azoxymethane (AOM-treated rat model. We found that 63 miRNAs were upregulated and miR-122, miR-296-5p and miR-503# were downregulated in the uninvolved colonic mucosa of AOM rats. We monitored the expression of selected miRNAs in colonic biopsies of AOM rats at 16 weeks and correlated it with tumor development. We noted that the tumor bearing rats had significantly greater miRNA modulation compared to those without tumors. The miRNAs showed good diagnostic performance with an area under the receiver operator curve (AUROC of >0.7. We also noted that the miRNA induction in the colonic mucosa was mirrorred in the mucus layer fecal colonocytes isolated from AOM rat stool and the degree of miRNA induction was greater in the tumor bearing rats compared to those without tumors. Lastly, we also noted significant miRNA modulation in the Pirc rats- the genetic model of colon carcinogenesis, both in the uninvolved colonic mucosa and the fecal colonocytes. We thus demonstrate that miRNAs are excellent markers of field carcinogenesis and could accurately predict future neoplasia. Based on our results, we propose an accurate, inexpensive, non-invasive miRNA test for CRC risk stratification based on rectal brushings or from abraded fecal colonocytes.

Dietary fish oil modulates the effect of dimethylhydrazine-induced colon cancer in rats

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Rasmy, G. E.; Khalil, W. K. B.; Moharib, S. A.; Kawab, A. A.; Jwanny, E. W.

2011-07-01

This study was conducted to examine the efficacy of fish oil supplementation in male wistar rat colon carcinogenesis. In order to induce colon cancer, the rats were given a weekly subcutaneous injection of 1,2-Dimethylhydrazine (DMH) at a dose of 20 mg/kg b.w. for five weeks. Afterwards, some of the rats ingested fish oil for either 4 weeks (DMH-FO4 group), or 17 weeks (DMH-FO17 group). The remaining rats continued without any supplementation for the same 4 weeks (DMH4 group), or 17 weeks (DMH17 group). Another two groups of rats did not receive the DMH and were given fish oil (FO17 group) or a normal diet only and considered as the control group (CN group). At the end of the experiment, the rats were sacrificed; and were subsequently subjected to biochemical and molecular biological analyses as well as histopathological examinations. The results showed increased levels of lactate dehydrogenase (LDH), malondialdehyde (MDA) and alkaline phosphatase (ALP) activities in the DMH rats compared to the control. The liver and colonic changes that were induced by DMH were significantly improved through fish oil supplementation in the DMH-FO17 group. The molecular analysis revealed that DMH treatment induced the expression alterations of genes p53, p27 and p21 and increased DNA band patterns related to cancer, while both FO17 and DMH-FO17 groups showed much better results. A histopathological examination of the DMH17 group revealed colon adenocarcinoma and several lesions in rat liver tissues. An improvement in the histopathological picture was seen in the livers and colons of groups DMHFO17. In conclusion, the present results demonstrated the anti-carciongenic effect of herring fish oil against DMH induced colon carcinogenesis in rats. The inhibitory effect of FO was due to the modulation of elevated biochemical parameters, DNA damage, gene expression and histopathological lesions caused by DMH. (Author) 70 refs.

An apple oligogalactan prevents against inflammation and carcinogenesis by targeting LPS/TLR4/NF-κB pathway in a mouse model of colitis-associated colon cancer.

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Liu, Li; Li, Yu H; Niu, Yin B; Sun, Yang; Guo, Zhen J; Li, Qian; Li, Chen; Feng, Juan; Cao, Shou S; Mei, Qi B

2010-10-01

Evidence strongly supported a link between inflammation and cancer. Patients with colitis have high risk for development of colon cancer. Nuclear factor-kappa B (NF-κB), partially induced by lipopolysaccharide (LPS) binding to Toll-like receptor (TLR) 4, is a vital molecule in supervising the transformation of colitis to colon cancer. It could be a good strategy to prevent colitis carcinogenesis for targeting LPS/TLR4/NF-κB pathway. In the present study, we obtained an oligogalactan composed of five galacturonic acids from apple pectin and evaluated its protective efficacy on intestinal toxicities and carcinogenesis in a mouse model of colitis-associated colon cancer induced by 1,2-dimethylhydrazine and dextran sodium sulfate (DSS). The apple oligogalactan (AOG) was highly effective against intestinal toxicities and carcinogenesis and decreased the elevated levels of TLR4 and tumor necrosis factor-α (TNF-α) induced by inflammation in vivo in this model system. In vitro studies, AOG alone only slightly increased the levels of protein expression and messenger RNA of TLR4, phosphorylation of IκBα and production of TNF-α in HT-29 cells. However, AOG significantly decreased the elevation of all the biomarkers induced by LPS when it was combined with LPS. The effect of AOG may be related to membrane internalization and redistribution of TLR4 from cell membrane to cytoplasm. AOG is active against inflammation and carcinogenesis through targeting LPS/TLR4/NF-κB pathway. Both AOG and LPS are agonists of TLR4 for sharing the same ligand but AOG has a much lower intrinsic activity than that of LPS. AOG may be useful for treatment of colitis and prevention of carcinogenesis in the clinics.

Short Chain Fatty Acids in the Colon and Peripheral Tissues: A Focus on Butyrate, Colon Cancer, Obesity and Insulin Resistance

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Sean M. McNabney

2017-12-01

Full Text Available Increased dietary fiber consumption has been associated with many beneficial effects, including amelioration of obesity and insulin resistance. These effects may be due to the increased production of short chain fatty acids, including propionate, acetate and butyrate, during fermentation of the dietary fiber in the colon. Indeed, oral and dietary supplementation of butyrate alone has been shown to prevent high fat-diet induced obesity and insulin resistance. This review focuses on sources of short chain fatty acids, with emphasis on sources of butyrate, mechanisms of fiber and butyrate metabolism in the gut and its protective effects on colon cancer and the peripheral effects of butyrate supplementation in peripheral tissues in the prevention and reversal of obesity and insulin resistance.

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

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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.

Lactobacillus salivarius CTC2197 Prevents Salmonella enteritidis Colonization in Chickens

OpenAIRE

Pascual, Mònica; Hugas, Marta; Badiola, Jose Ignacio; Monfort, Josep Maria; Garriga, Margarita

1999-01-01

A rifampin-resistant Lactobacillus salivarius strain, CTC2197, was assessed as a probiotic in poultry, by studying its ability to prevent Salmonella enteritidis C-114 colonization in chickens. When the probiotic strain was dosed by oral gavage together with S. enteritidis C-114 directly into the proventriculus in 1-day-old Leghorn chickens, the pathogen was completely removed from the birds after 21 days. The same results were obtained when the probiotic strain was also administered through t...

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.

Increase in intracellular PGE2 induces apoptosis in Bax-expressing colon cancer cell

International Nuclear Information System (INIS)

Lalier, Lisenn; Pedelaborde, François; Braud, Christophe; Menanteau, Jean; M Vallette, François; Olivier, Christophe

2011-01-01

NSAIDs exhibit protective properties towards some cancers, especially colon cancer. Yet, it is not clear how they play their protective role. PGE 2 is generally shown as the only target of the NSAIDs anticancerous activity. However, PGE 2 known targets become more and more manifold, considering both the molecular pathways involved and the target cells in the tumour. The role of PGE 2 in tumour progression thus appears complex and multipurpose. To gain understanding into the role of PGE 2 in colon cancer, we focused on the activity of PGE 2 in apoptosis in colon cancer cell lines. We observed that an increase in intracellular PGE 2 induced an apoptotic cell death, which was dependent on the expression of the proapoptotic protein Bax. This increase was induced by increasing PGE 2 intracellular concentration, either by PGE 2 microinjection or by the pharmacological inhibition of PGE 2 exportation and enzymatic degradation. We present here a new sight onto PGE 2 in colon cancer cells opening the way to a new prospective therapeutic strategy in cancer, alternative to NSAIDs

Cytotoxicity of p-chloroamphetamine in dimethylhydrazine-induced carcinomata of rat colon.

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Tutton, P J; Barkla, D H

1979-01-01

Previous studies have shown that several serotonin-related compounds are cytotoxic to dimethylhydrazine-induced carcinomata of the colon of rat. This paper reports the cytotoxicity of another serotonin-related compound, p-chloroamphetamine.

Complex of MUC1, CIN85 and Cbl in Colon Cancer Progression and Metastasis

International Nuclear Information System (INIS)

Cascio, Sandra; Finn, Olivera J.

2015-01-01

We previously reported that CIN85, an 85 KDa protein known to be involved in tumor cell migration and metastasis through its interaction with Cbl, associates with MUC1 in tumor cells. MUC1/CIN85 complex also regulates migration and invasion of tumor cells in vitro. Here, we examined specifically human colon carcinoma tissue microarrays (TMA) by immunohistochemistry for the expression of MUC1 and CIN85 and their potential role in cancer progression and metastasis. We detected a significant increase in expression of both MUC1 and CIN85 associated with advanced tumor stage and lymph node metastasis. We further investigated if Cbl could also be present in the MUC1/CIN85 complex. Co-immunoprecipitation assay showed that Cbl co-localized both with CIN85 and with MUC1 in a human colon cancer cell line. To begin to investigate the in vivo relevance of MUC1 overexpression and association with CIN85 and Cbl in cancer development and progression, we used human MUC1 transgenic mice that express MUC1 on the colonic epithelial cells, treated with azoxymethane to initiate and dextran sulfate sodium (AOM/DSS) to promote colorectal carcinogenesis. MUC1.Tg mice showed higher tumor incidence and decreased survival when compared with wild-type mice. Consistent with the in vitro data, the association of MUC1, CIN85 and Cbl was detected in colon tissues of AOM/DSS-treated MUC1 transgenic mice. MUC1/CIN85/Cbl complex appears to contribute to promotion and progression of colon cancer and thus increased expression of MUC1, CIN85 and Cbl in early stage colon cancer might be predictive of poor prognosis

Complex of MUC1, CIN85 and Cbl in Colon Cancer Progression and Metastasis

Energy Technology Data Exchange (ETDEWEB)

Cascio, Sandra, E-mail: sac131@pitt.edu [Department of Immunology, University of Pittsburgh School of Medicine, E1040 Biomedical Science Tower, Pittsburgh, PA 15261 (United States); Fondazione Ri.Med, via Bandiera, Palermo 90133 (Italy); Finn, Olivera J., E-mail: sac131@pitt.edu [Department of Immunology, University of Pittsburgh School of Medicine, E1040 Biomedical Science Tower, Pittsburgh, PA 15261 (United States)

2015-02-10

We previously reported that CIN85, an 85 KDa protein known to be involved in tumor cell migration and metastasis through its interaction with Cbl, associates with MUC1 in tumor cells. MUC1/CIN85 complex also regulates migration and invasion of tumor cells in vitro. Here, we examined specifically human colon carcinoma tissue microarrays (TMA) by immunohistochemistry for the expression of MUC1 and CIN85 and their potential role in cancer progression and metastasis. We detected a significant increase in expression of both MUC1 and CIN85 associated with advanced tumor stage and lymph node metastasis. We further investigated if Cbl could also be present in the MUC1/CIN85 complex. Co-immunoprecipitation assay showed that Cbl co-localized both with CIN85 and with MUC1 in a human colon cancer cell line. To begin to investigate the in vivo relevance of MUC1 overexpression and association with CIN85 and Cbl in cancer development and progression, we used human MUC1 transgenic mice that express MUC1 on the colonic epithelial cells, treated with azoxymethane to initiate and dextran sulfate sodium (AOM/DSS) to promote colorectal carcinogenesis. MUC1.Tg mice showed higher tumor incidence and decreased survival when compared with wild-type mice. Consistent with the in vitro data, the association of MUC1, CIN85 and Cbl was detected in colon tissues of AOM/DSS-treated MUC1 transgenic mice. MUC1/CIN85/Cbl complex appears to contribute to promotion and progression of colon cancer and thus increased expression of MUC1, CIN85 and Cbl in early stage colon cancer might be predictive of poor prognosis.

Mechanisms underlying 3-bromopyruvate-induced cell death in colon cancer.

Science.gov (United States)

Sun, Yiming; Liu, Zhe; Zou, Xue; Lan, Yadong; Sun, Xiaojin; Wang, Xiu; Zhao, Surong; Jiang, Chenchen; Liu, Hao

2015-08-01

3-Bromopyruvate (3BP) is an energy-depleting drug that inhibits Hexokinase II activity by alkylation during glycolysis, thereby suppressing the production of ATP and inducing cell death. As such, 3BP can potentially serve as an anti-tumorigenic agent. Our previous research showed that 3BP can induce apoptosis via AKT /protein Kinase B signaling in breast cancer cells. Here we found that 3BP can also induce colon cancer cell death by necroptosis and apoptosis at the same time and concentration in the SW480 and HT29 cell lines; in the latter, autophagy was also found to be a mechanism of cell death. In HT29 cells, combined treatment with 3BP and the autophagy inhibitor 3-methyladenine (3-MA) exacerbated cell death, while viability in 3BP-treated cells was enhanced by concomitant treatment with the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp fluoromethylketone (z-VAD-fmk) and the necroptosis inhibitor necrostatin (Nec)-1. Moreover, 3BP inhibited tumor growth in a SW480 xenograft mouse model. These results indicate that 3BP can suppress tumor growth and induce cell death by multiple mechanisms at the same time and concentration in different types of colon cancer cell by depleting cellular energy stores.

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.

Probiotic Strain Lactobacillus casei BL23 Prevents Colitis-Associated Colorectal Cancer

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Elsa Jacouton

2017-11-01

Full Text Available The gut microbiota plays a major role in intestinal health, and an imbalance in its composition can lead to chronic gut inflammation and a predisposition to developing colorectal cancer (CRC. Currently, the use of probiotic bacteria represents an emerging alternative to treat and prevent cancer. Moreover, consumption of these beneficial bacteria may also favorably modulate the composition of the gut microbiota, which has been described in several studies to play an important role in CRC carcinogenesis. In this context, the aim of this study was to assess the protective effect of oral treatment with Lactobacillus casei BL23, a probiotic strain well known for its anti-inflammatory and anticancer properties. First, CRC was induced in C57BL6 mice by a single intraperitoneal injection with azoxymethane (8 mg/kg, followed by four courses of dextran sodium sulfate (2.5% in drinking water that were separated by an adjustable recovery period. At the time of sacrifice (day 46, tumor incidence, histological scores, and epithelial proliferation were determined in colon samples. Our results show that L. casei BL23 significantly protected mice against CRC development; specifically, L. casei BL23 treatment reduced histological scores and proliferative index values. In addition, our analysis revealed that L. casei BL23 had an immunomodulatory effect, mediated through the downregulation of the IL-22 cytokine, and an antiproliferative effect, mediated through the upregulation of caspase-7, caspase-9, and Bik. Finally, L. casei BL23 treatment tended to counterbalance CRC-induced dysbiosis in mice, as demonstrated by an analysis of fecal microbiota. Altogether our results demonstrate the high potential of L. casei BL23 for the development of new, probiotic-based strategies to fight CRC.

Tumor associated macrophages protect colon cancer cells from TRAIL-induced apoptosis through IL-1beta-dependent stabilization of Snail in tumor cells.

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Pawan Kaler

2010-07-01

Full Text Available We recently reported that colon tumor cells stimulate macrophages to release IL-1beta, which in turn inactivates GSK3beta and enhances Wnt signaling in colon cancer cells, generating a self-amplifying loop that promotes the growth of tumor cells.Here we describe that macrophages protect HCT116 and Hke-3 colon cancer cells from TRAIL-induced apoptosis. Inactivation of IL-1beta by neutralizing IL-1beta antibody, or silencing of IL-1beta in macrophages inhibited their ability to counter TRAIL-induced apoptosis. Accordingly, IL-1beta was sufficient to inhibit TRAIL-induced apoptosis. TRAIL-induced collapse of the mitochondrial membrane potential (Delta psi and activation of caspases were prevented by macrophages or by recombinant IL-1beta. Pharmacological inhibition of IL-1beta release from macrophages by vitamin D(3, a potent chemopreventive agent for colorectal cancer, restored the ability of TRAIL to induce apoptosis of tumor cells cultured with macrophages. Macrophages and IL-1beta failed to inhibit TRAIL-induced apoptosis in HCT116 cells expressing dnIkappaB, dnAKT or dnTCF4, confirming that they oppose TRAIL-induced cell death through induction of Wnt signaling in tumor cells. We showed that macrophages and IL-1beta stabilized Snail in tumor cells in an NF-kappaB/Wnt dependent manner and that Snail deficient tumor cells were not protected from TRAIL-induced apoptosis by macrophages or by IL-1beta, demonstrating a crucial role of Snail in the resistance of tumor cells to TRAIL.We have identified a positive feedback loop between tumor cells and macrophages that propagates the growth and promotes the survival of colon cancer cells: tumor cells stimulate macrophages to secrete IL-1beta, which in turn, promotes Wnt signaling and stabilizes Snail in tumor cells, conferring resistance to TRAIL. Vitamin D(3 halts this amplifying loop by interfering with the release of IL-1beta from macrophages. Accordingly, vitamin D(3 sensitizes tumor cells to TRAIL-induced

Oncogenic KRAS activates an embryonic stem cell-like program in human colon cancer initiation.

Science.gov (United States)

Le Rolle, Anne-France; Chiu, Thang K; Zeng, Zhaoshi; Shia, Jinru; Weiser, Martin R; Paty, Philip B; Chiu, Vi K

2016-01-19

Colorectal cancer is the third most frequently diagnosed cancer worldwide. Prevention of colorectal cancer initiation represents the most effective overall strategy to reduce its associated morbidity and mortality. Activating KRAS mutation (KRASmut) is the most prevalent oncogenic driver in colorectal cancer development, and KRASmut inhibition represents an unmet clinical need. We apply a systems-level approach to study the impact of KRASmut on stem cell signaling during human colon cancer initiation by performing gene set enrichment analysis on gene expression from human colon tissues. We find that KRASmut imposes the embryonic stem cell-like program during human colon cancer initiation from colon adenoma to stage I carcinoma. Expression of miR145, an embryonic SC program inhibitor, promotes cell lineage differentiation marker expression in KRASmut colon cancer cells and significantly suppresses their tumorigenicity. Our data support an in vivo plasticity model of human colon cancer initiation that merges the intrinsic stem cell properties of aberrant colon stem cells with the embryonic stem cell-like program induced by KRASmut to optimize malignant transformation. Inhibition of the embryonic SC-like program in KRASmut colon cancer cells reveals a novel therapeutic strategy to programmatically inhibit KRASmut tumors and prevent colon cancer.

Radiation-induced dysfunction of colonic transport: role of enteric nervous system and of serotonine

International Nuclear Information System (INIS)

Francois, Agnes

1998-01-01

One of the most commonly observed features of radiation-induced injury of the gastrointestinal tract is the appearance of severe diarrhea. One difficulty in understanding the origin of radiation-induced diarrhea is the multiplicity of factors implicated, depending on the type of radiation, the dose received and the irradiated field. Colonic transport is regulated for a great part by the enteric nervous system (ENS), in close association with immunocompetent cells, especially mast cells. The aim of this study was to investigate whether the neuro-immune regulation of colonic transport could be implicated in radiation-induced attenuation and recovery of colonic functions. Male Wistar rats were whole-body irradiated at 3.8 Gy neutron or 5 and 10 Gy gamma. At 1 and 3 days after exposure, the colonic epithelium was hypo-responsive to neural stimulation (submucosal plexus). Mechanistic studies were performed after 10 Gy exposure. The decreased colonic transport was associated with the disappearance of both submucosal mast cells and histamine-mediated pathway, together with decreased responses to exogenous histamine. Similarly, the response to exogenous 5-HT was decreased, without any modification of either the neural (5-HT 3 ) or non-neural (5-HT 4 ) pathways. Seven days after exposure, colonic transport capacity returned to normal in spite of the absence of mast cells. However these observations were associated with the reappearance of a histaminergic pathway, the origin of which is still unknown. The part played by 5-HT 3 receptors was increased, together with the appearance of a neurally-associated 5-HT4 receptor-pathway. These results suggest that the decreased influence of the ENS on colonic transport observed 1 and 3 days after exposure may be due to both the disappearance of neuro-immune links and the hypo-responsiveness of colonic epithelium to the mediators released by ENS. The functional recovery at seven days may be related on one hand to the return of altered

Trypanosomiasis-induced megacolon illustrates how myenteric neurons modulate the risk for colon cancer in rats and humans.

Directory of Open Access Journals (Sweden)

Vinicius Kannen

2015-04-01

Full Text Available Trypanosomiasis induces a remarkable myenteric neuronal degeneration leading to megacolon. Very little is known about the risk for colon cancer in chagasic megacolon patients. To clarify whether chagasic megacolon impacts on colon carcinogenesis, we investigated the risk for colon cancer in Trypanosoma cruzi (T. cruzi infected patients and rats.Colon samples from T. cruzi-infected and uninfected patients and rats were histopathologically investigated with colon cancer biomarkers. An experimental model for chemical myenteric denervation was also performed to verify the myenteric neuronal effects on colon carcinogenesis. All experiments complied the guidelines and approval of ethical institutional review boards.No colon tumors were found in chagasic megacolon samples. A significant myenteric neuronal denervation was observed. Epithelial cell proliferation and hyperplasia were found increased in chagasic megacolon. Analyzing the argyrophilic nucleolar organiser regions within the cryptal bottom revealed reduced risk for colon cancer in Chagas' megacolon patients. T. cruzi-infected rats showed a significant myenteric neuronal denervation and decreased numbers of colon preneoplastic lesions. In chemical myenteric denervated rats preneoplastic lesions were reduced from the 2nd wk onward, which ensued having the colon myenteric denervation significantly induced.Our data suggest that the trypanosomiasis-related myenteric neuronal degeneration protects the colon tissue from carcinogenic events. Current findings highlight potential mechanisms in tropical diseases and cancer research.

Electrical stimulation induces propagated colonic contractions in an experimental model.

Science.gov (United States)

Aellen, S; Wiesel, P H; Gardaz, J-P; Schlageter, V; Bertschi, M; Virag, N; Givel, J-C

2009-02-01

Direct colonic electrical stimulation may prove to be a treatment option for specific motility disorders such as chronic constipation. The aim of this study was to provoke colonic contractions using electrical stimulation delivered from a battery-operated device. Electrodes were inserted into the caecal seromuscular layer of eight anaesthetized pigs. Contractions were induced by a neurostimulator (Medtronic 3625). Caecal motility was measured simultaneously by video image analysis, manometry and a technique assessing colonic transit. Caecal contractions were generated using 8-10 V amplitude, 1000 micros pulse width, 120 Hz frequency for 10-30 s, with an intensity of 7-15 mA. The maximal contraction strength was observed after 20-25 s. Electrical stimulation was followed by a relaxation phase of 1.5-2 min during which contractions propagated orally and aborally over at least 10 cm. Spontaneous and stimulated caecal motility values were significantly different for both intraluminal pressure (mean(s.d.) 332(124) and 463(187) mmHg respectively; P < 0.001, 42 experiments) and movement of contents (1.6(0.9) and 3.9(2.8) mm; P < 0.001, 40 experiments). Electrical stimulation modulated caecal motility, and provoked localized and propagated colonic contractions.

Vanillin improves and prevents trinitrobenzene sulfonic acid-induced colitis in mice.

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Wu, Shih-Lu; Chen, Jaw-Chyun; Li, Chia-Cheng; Lo, Hsin-Yi; Ho, Tin-Yun; Hsiang, Chien-Yun

2009-08-01

Inflammatory bowel disease (IBD) is chronic inflammatory and relapsing disease of the gut. It has been known that activation of nuclear factor-kappaB (NF-kappaB) and production of proinflammatory cytokines play important roles in the pathogenesis of IBD. In this study, the effect of vanillin (4-hydroxy-3-methoxybenzaldehyde), a potent nuclear factor-kappaB (NF-kappaB) inhibitor, was evaluated in mice with trinitrobenzene sulfonic acid (TNBS)-induced colitis. Oral administration of vanillin improved macroscopic and histological features of TNBS-induced colitis in a dose-dependent manner. Vanillin not only prevented TNBS-induced colitis but also ameliorated the established colitis. By in vivo NF-kappaB bioluminescence imaging, electrophoretic mobility shift assay, and Western blot, we found that vanillin suppressed in vivo NF-kappaB activities through the inhibition of p65 translocation, inhibitor of nuclear factor-kappaB(IkappaB)-alpha phosphorylation, and IkappaB kinase activation. Furthermore, vanillin reduced the expressions of proinflammatory cytokines [interleukin (IL)-1beta, IL-6, interferon-gamma, and tumor necrosis factor-alpha] and stimulated the expression of anti-inflammatory cytokine (IL-4) in colonic tissues. In conclusion, this work identified vanillin as an anti-inflammatory compound with the capacity to prevent and ameliorate TNBS-induced colitis. Due to its safety, vanillin could be a potent candidate for the treatment of IBD.

Cytomegalovirus-induced colonic stricture presenting as acute intestinal obstruction in an immunocompetent adult.

Science.gov (United States)

Dinesh, B V; Selvaraju, Karthikeyan; Kumar, Sampath; Thota, Sumath

2013-09-10

Cytomegalovirus (CMV) infection causes significant morbidty and mortality in immunopromised patients. Though it is usually silent in immunocompetent adults, rarely it can cause serious life-threatening complications. Gastrointestinal tract is one of the commonly involved organs, where it produces a spectrum of clinical manifestation ranging from mild non-specific abdominal pain and diarrhoea to severe infection with toxic megacolon and death. We present a 65-year-old immunocompetent male patient admitted with acute colonic obstruction secondary to CMV-induced colonic stricture, highlighting the importance of considering it as a differential diagnosis for colonic obstruction and reviewing its management.

Dietary heme induces instantaneous oxidative stress but delayed cytotoxicity and compensatory hyperproliferation in mouse colon

NARCIS (Netherlands)

IJssennagger, Noortje; Rijnierse, A.; Wit, de Nicole; Boekschoten, Mark; Dekker, Jan; Schonewille, Arjan; Muller, Michael; Meer, van der Roelof

2013-01-01

Red meat consumption is associated with an increased colon cancer risk. Heme, present in red meat, injures the colon surface epithelium by luminal cytotoxicity and reactive oxygen species. This surface injury is compensated by hyperproliferation and hyperplasia of crypt cells, which was induced by a

Probiotic Bifidobacterium breve induces IL-10-producing Tr1 cells in the colon.

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Seong Gyu Jeon

Full Text Available Specific intestinal microbiota has been shown to induce Foxp3(+ regulatory T cell development. However, it remains unclear how development of another regulatory T cell subset, Tr1 cells, is regulated in the intestine. Here, we analyzed the role of two probiotic strains of intestinal bacteria, Lactobacillus casei and Bifidobacterium breve in T cell development in the intestine. B. breve, but not L. casei, induced development of IL-10-producing Tr1 cells that express cMaf, IL-21, and Ahr in the large intestine. Intestinal CD103(+ dendritic cells (DCs mediated B. breve-induced development of IL-10-producing T cells. CD103(+ DCs from Il10(-/-, Tlr2(-/-, and Myd88(-/- mice showed defective B. breve-induced Tr1 cell development. B. breve-treated CD103(+ DCs failed to induce IL-10 production from co-cultured Il27ra(-/- T cells. B. breve treatment of Tlr2(-/- mice did not increase IL-10-producing T cells in the colonic lamina propria. Thus, B. breve activates intestinal CD103(+ DCs to produce IL-10 and IL-27 via the TLR2/MyD88 pathway thereby inducing IL-10-producing Tr1 cells in the large intestine. Oral B. breve administration ameliorated colitis in immunocompromised mice given naïve CD4(+ T cells from wild-type mice, but not Il10(-/- mice. These findings demonstrate that B. breve prevents intestinal inflammation through the induction of intestinal IL-10-producing Tr1 cells.

Probiotic Bifidobacterium breve induces IL-10-producing Tr1 cells in the colon.

Science.gov (United States)

Jeon, Seong Gyu; Kayama, Hisako; Ueda, Yoshiyasu; Takahashi, Takuya; Asahara, Takashi; Tsuji, Hirokazu; Tsuji, Noriko M; Kiyono, Hiroshi; Ma, Ji Su; Kusu, Takashi; Okumura, Ryu; Hara, Hiromitsu; Yoshida, Hiroki; Yamamoto, Masahiro; Nomoto, Koji; Takeda, Kiyoshi

2012-01-01

Specific intestinal microbiota has been shown to induce Foxp3(+) regulatory T cell development. However, it remains unclear how development of another regulatory T cell subset, Tr1 cells, is regulated in the intestine. Here, we analyzed the role of two probiotic strains of intestinal bacteria, Lactobacillus casei and Bifidobacterium breve in T cell development in the intestine. B. breve, but not L. casei, induced development of IL-10-producing Tr1 cells that express cMaf, IL-21, and Ahr in the large intestine. Intestinal CD103(+) dendritic cells (DCs) mediated B. breve-induced development of IL-10-producing T cells. CD103(+) DCs from Il10(-/-), Tlr2(-/-), and Myd88(-/-) mice showed defective B. breve-induced Tr1 cell development. B. breve-treated CD103(+) DCs failed to induce IL-10 production from co-cultured Il27ra(-/-) T cells. B. breve treatment of Tlr2(-/-) mice did not increase IL-10-producing T cells in the colonic lamina propria. Thus, B. breve activates intestinal CD103(+) DCs to produce IL-10 and IL-27 via the TLR2/MyD88 pathway thereby inducing IL-10-producing Tr1 cells in the large intestine. Oral B. breve administration ameliorated colitis in immunocompromised mice given naïve CD4(+) T cells from wild-type mice, but not Il10(-/-) mice. These findings demonstrate that B. breve prevents intestinal inflammation through the induction of intestinal IL-10-producing Tr1 cells.

Dietary elevated sucrose modulation of diesel-induced genotoxicity in the colon and liver of Big Blue rats

DEFF Research Database (Denmark)

Risom, L.; Moller, P.; Hansen, Max

2003-01-01

Earlier studies have indicated that sucrose possesses either co-carcinogenic or tumor-promoter effects in colon carcinogenesis induced by genotoxic carcinogens. In this study we investigated the role of sucrose on diesel exhaust particle (DEP)-induced genotoxicity in the colonic mucosa and liver......-breaks and DNA adducts in liver. DEP and sucrose treatment did not have any effect on mutation frequency in colon and liver. Oxidative DNA damage detected as 8-oxodG (8-oxo-7,8-dihydro-2'-deoxyguanosine) and endonuclease III or formamidopyrimidine DNA glycosylase sensitive sites was unaltered in colon and liver....... The mRNA expression levels of the DNA repair enzymes N-methylpurine DNA glycosylase (MPG), 8-oxoguanine DNA glycosylase (OGG1) and ERCC1 (part of the nucleotide excision repair complex) measured by reverse transcription-polymerase chain reaction were increased in liver by DEP feeding. In colon...

Deoxycholate, an Endogenous Cytotoxin/Genotoxin, Induces the Autophagic Stress-Survival Pathway: Implications for Colon Carcinogenesis

Directory of Open Access Journals (Sweden)

Claire M. Payne

2009-01-01

Full Text Available We report that deoxycholate (DOC, a hydrophobic bile acid associated with a high-fat diet, activates the autophagic pathway in non-cancer colon epithelial cells (NCM-460, and that this activation contributes to cell survival. The DOC-induced increase in autophagy was documented by an increase in autophagic vacuoles (detected using transmission electron microscopy, increased levels of LC3-I and LC3-II (western blotting, an increase in acidic vesicles (fluorescence spectroscopy of monodansycadaverine and lysotracker red probes, and increased expression of the autophagic protein, beclin-1 (immunohistochemistry/western blotting. The DOC-induced increase in beclin-1 expression was ROS-dependent. Rapamycin (activator of autophagy pre-treatment of NCM-460 cells significantly (P<.05 decreased, and 3-MA (inhibitor of autophagy significantly (P<.05 increased the cell loss caused by DOC treatment, alone. Rapamycin pre-treatment of the apoptosis-resistant colon cancer cell line, HCT-116RC (developed in our laboratory, resulted in a significant decrease in DOC-induced cell death. Bafilomycin A1 and hydroxychloroquine (inhibitors of the autophagic process increased the DOC-induced percentage of apoptotic cells in HCT-116RC cells. It was concluded that the activation of autophagy by DOC has important implications for colon carcinogenesis and for the treatment of colon cancer in conjunction with commonly used chemotherapeutic agents.

Chemopreventive effect of Cynodon dactylon (L.) Pers. extract against DMH-induced colon carcinogenesis in experimental animals.

Science.gov (United States)

Albert-Baskar, Arul; Ignacimuthu, Savarimuthu

2010-07-01

The present study was aimed at evaluating the chemopreventive property of Cynodon dactylon. The antioxidant, antiproliferative and apoptotic potentials of the plant were investigated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, nitric oxide radical scavenging activity (NO(-)) and MTT assay on four cancer cell lines (COLO 320 DM, MCH-7, AGS, A549) and a normal cell line (VERO). In vivo chemopreventive property of the plant extract was studied in DMH-induced colon carcinogenesis. The methanolic extract of C. dactylon was found to be antiproliferative and antioxidative at lower concentrations and induced apoptotic cell death in COLO 320 DM cells. Treatment with methanolic extract of C. dactylon increased the levels of antioxidant enzymes and reduced the number of dysplastic crypts in DMH-induced colon of albino rats. The present investigation revealed the anticancer potential of methanolic extract of C. dactylon in COLO 320 DM cells and experimentally induced colon carcinogenesis in rats.

Dietary heme-mediated PPARα activation does not affect the heme-induced epithelial hyperproliferation and hyperplasia in mouse colon.

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Noortje Ijssennagger

Full Text Available Red meat consumption is associated with an increased colon cancer risk. Heme, present in red meat, injures the colon surface epithelium by luminal cytotoxicity and reactive oxygen species. This surface injury is overcompensated by hyperproliferation and hyperplasia of crypt cells. Transcriptome analysis of mucosa of heme-fed mice showed, besides stress- and proliferation-related genes, many upregulated lipid metabolism-related PPARα target genes. The aim of this study was to investigate the role of PPARα in heme-induced hyperproliferation and hyperplasia. Male PPARα KO and WT mice received a purified diet with or without heme. As PPARα is proposed to protect against oxidative stress and lipid peroxidation, we hypothesized that the absence of PPARα leads to more surface injury and crypt hyperproliferation in the colon upon heme-feeding. Heme induced luminal cytotoxicity and lipid peroxidation and colonic hyperproliferation and hyperplasia to the same extent in WT and KO mice. Transcriptome analysis of colonic mucosa confirmed similar heme-induced hyperproliferation in WT and KO mice. Stainings for alkaline phosphatase activity and expression levels of Vanin-1 and Nrf2-targets indicated a compromised antioxidant defense in heme-fed KO mice. Our results suggest that the protective role of PPARα in antioxidant defense involves the Nrf2-inhibitor Fosl1, which is upregulated by heme in PPARα KO mice. We conclude that PPARα plays a protective role in colon against oxidative stress, but PPARα does not mediate heme-induced hyperproliferation. This implies that oxidative stress of surface cells is not the main determinant of heme-induced hyperproliferation and hyperplasia.

Ischemic or toxic injury: A challenging diagnosis and treatment of drug-induced stenosis of the sigmoid colon.

Science.gov (United States)

Zhang, Zong-Ming; Lin, Xiang-Chun; Ma, Li; Jin, An-Qin; Lin, Fang-Cai; Liu, Zhuo; Liu, Li-Min; Zhang, Chong; Zhang, Na; Huo, Li-Juan; Jiang, Xue-Liang; Kang, Feng; Qin, Hong-Jun; Li, Qiu-Yang; Yu, Hong-Wei; Deng, Hai; Zhu, Ming-Wen; Liu, Zi-Xu; Wan, Bai-Jiang; Yang, Hai-Yan; Liao, Jia-Hong; Luo, Xu; Li, You-Wei; Wei, Wen-Ping; Song, Meng-Meng; Zhao, Yue; Shi, Xue-Ying; Lu, Zhao-Hui

2017-06-07

A 48-year-old woman was admitted with 15-mo history of abdominal pain, diarrhea and hematochezia, and 5-mo history of defecation difficulty. She had been successively admitted to nine hospitals, with an initial diagnosis of inflammatory bowel disease with stenotic sigmoid colon. Findings from computed tomography virtual colonoscopy, radiography with meglumine diatrizoate, endoscopic balloon dilatation, metallic stent implantation and later overall colonoscopy, coupled with the newfound knowledge of compound Qingdai pill-taking, led to a subsequent diagnosis of ischemic or toxic bowel disease with sigmoid colon stenosis. The patient was successfully treated by laparoscopic sigmoid colectomy, and postoperative pathological examination revealed ischemic or toxic injury of the sigmoid colon, providing a final diagnosis of drug-induced sigmoid colon stenosis. This case highlights that adequate awareness of drug-induced colon stenosis has a decisive role in avoiding misdiagnosis and mistreatment. The diagnostic and therapeutic experiences learnt from this case suggest that endoscopic balloon expansion and colonic metallic stent implantation as bridge treatments were demonstrated as crucial for the differential diagnosis of benign colonic stenosis. Skillful surgical technique and appropriate perioperative management helped to ensure the safety of our patient in subsequent surgery after long-term use of glucocorticoids.

The role of substance P in the maintenance of colonic hypermotility induced by repeated stress in rats.

Science.gov (United States)

Lu, Ping; Luo, Hesheng; Quan, Xiaojing; Fan, Han; Tang, Qincai; Yu, Guang; Chen, Wei; Xia, Hong

2016-04-01

The mechanism underlying chronic stress-induced gastrointestinal (GI) dysmotility has not been fully elucidated and GI hormones have been indicated playing a role in mediating stress-induced changes in GI motor function. Our objective was to study the possible role of substance P (SP) in the colonic hypermotility induced by repeated water avoidance stress (WAS) which mimics irritable bowel syndrome. Male Wistar rats were submitted to WAS or sham WAS (SWAS) (1h/day) for up to 10 consecutive days. Enzyme Immunoassay Kit was used to detect the serum level of SP. The expression of neurokinin-1 receptor (NK1R) was investigated by Immunohistochemistry and Western blotting. The spontaneous contraction of muscle strip was studied in an organ bath system. L-type calcium channel currents (ICa,L) of smooth muscle cells (SMCs) were recorded by whole-cell patch-clamp technique. Fecal pellet expulsion and spontaneous contraction of proximal colon in rats were increased after repeated WAS. The serum level of SP was elevated following WAS. Immunohistochemistry proved the expression of NK1R in mucosa, muscularis and myenteric plexus. Western blotting demonstrated stress-induced up-regulation of NK1R in colon devoid of mucosa and submucosa. Repeated WAS increased the contractile activities of longitudinal muscle and circular muscle strips induced by SP and this effect was reversed by a selective NK1R antagonist. The ICa,L of SMCs in the WAS rats were drastically increased compared to controls after addition of SP. Increased serum SP level and up-regulated NK1R in colon may contribute to stress-induced colonic hypermotility. And L-type calcium channels play a potentially important role in the process of WAS-induced dysmotility. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simethicone to prevent colonic bubbles during CT colonography performed with polyethylene glycol lavage and iohexol tagging: a randomized clinical trial.

Science.gov (United States)

Hong, Gil-Sun; Park, Seong Ho; Kim, Bohyun; Lee, Ju Hee; Kim, Jin Cheon; Yu, Chang Sik; Baek, Seunghee; Lee, Jong Seok; Kim, Hyun Jin

2015-04-01

The purpose of this study was to determine whether the occurrence of numerous colonic bubbles during CT colonography (CTC) performed with polyethylene glycol cleansing and oral iohexol fecal/fluid tagging could be prevented by use of simethicone. Adults with suspected colonic neoplasia who had been randomly assigned to control and simethicone intervention groups underwent CTC after cleansing with 4 L of polyethylene glycol, tagging with 50 mL of 350 mg I/mL oral iohexol, and without (control) or with (intervention) oral administration of 200 mg of simethicone. Colonic segments in the control and intervention groups were evaluated for amount of colonic bubbles during CTC. A 6-point grading system was used in which 0 indicated no bubbles and 5 indicated that more than three fourths of the air-distended mucosa was covered with bubbles. The primary endpoint was a per-patient colonic bubble grade, derived as an average of the segmental grades. Eighty adults with suspected colonic neoplasia were randomly assigned to the control (40 patients) and simethicone intervention (40 patients) groups. A total of 659 colonic segments in the control group and 689 segments in the intervention group were evaluated for amount of colonic bubbles during CTC. The per-patient colonic bubble score was significantly lower in the simethicone intervention group than in the control group. The mean score was 0.0±0.1 (SD) versus 1.2±0.8 (pgrade 0, and 16 (2.3%) were grade 1. In contrast, in the control group, 226 (34.3%) segments were grade 0; 173 (26.3%), grade 1; 175 (26.6%), grade 2; 45 (6.8%), grade 3; 23 (3.5%), grade 4; and 17 (2.6%), grade 5. The colonic bubbles associated with fecal/fluid tagging with iohexol can be successfully prevented by adding simethicone to the colonic preparation.

The influence of arachidonic acid metabolites on cell division in the intestinal epithelium and in colonic tumors.

Science.gov (United States)

Petry, F M; Tutton, P J; Barkla, D H

1984-09-01

Various metabolites of arachidonic acid are now known to influence cell division. In this paper the effects on cell proliferation of arachidonic acid, some inhibitors of arachidonic acid metabolism and some analogs of arachidonic acid metabolites is described. The epithelial cell proliferation rate in the jejunum, in the descending colon and in dimethylhydrazine-induced tumors of rat colon was measured using a stathmokinetic technique. Administration of arachidonic acid resulted in retardation of cell proliferation in each of the tissues examined. A cyclooxygenase inhibitor (Flurbiprofen) prevented this effect of arachidonic acid in the jejunal crypts and in colonic tumors, but not in colonic crypts. In contrast, inhibitors of both cyclooxygenase and lipoxygenase (Benoxaprofen and BW755c) prevented the effect of arachidonic acid in the colonic crypts and reduced its effect on colonic tumours but did not alter its effect on the jejunum. An inhibitor of thromoboxane A2 synthetase (U51,605) was also able to prevent the inhibitory effect of arachidonic acid on colonic tumors. Treatment with 16,16-dimethyl PGE2 inhibited cell proliferation in jejunal crypts and in colonic tumors, as did a thromboxane A2 mimicking agent, U46619. Nafazatrom, an agent that stimulates prostacyclin synthesis and inhibits lypoxygenase, promoted cell proliferation in the jejunal crypts and colonic crypts, but inhibited cell proliferation in colonic tumours.

Dietary low-dose sucrose modulation of IQ-induced genotoxicity in the colon and liver of Big Blue((TM)) rats

DEFF Research Database (Denmark)

Moller, P.; Hansen, Max; Autrup, H.

2003-01-01

Earlier studies have indicated that sucrose increases 2-amino-3-methylimidazo[4,5-f]quinoline (IQ)-induced aberrant crypt foci in the colon. In this study, we investigated the role of sucrose in IQ-induced genotoxicity of the colon mucosa and liver. Big Blue(TM) rats were fed with IQ (20 ppm...... in feed) and/or sucrose (3.45 or 6.85 wt.% in feed) for 3 weeks. IQ increased DNA strand breaks in the colon, whereas the mutation frequency was increased in the liver. The level of IQ-induced DNA adducts was elevated in both colon mucosa cells and liver. In the liver, high sucrose intake increased...... the level of DNA adducts above that of IQ and low sucrose intake. Oxidative DNA damage detected in terms of 7-hydro-8-oxo-2'-deoxyguanosine by HPLC-EC, or endonuclease HI or formamidopyrimidine DNA glycosylase sensitive sites were unaltered in the colon and liver. Expression of ERCC1 and OGG1 mRNA levels...

Radiation-induced colon cancer with high frequency microsatellite instability (MSI-H), report of a case

International Nuclear Information System (INIS)

Arai, Masami; Ueno, Masashi; Koizumi, Koichi

2002-01-01

We report a 67-year-old female with radiation-induced colon cancer which developed 23 years after radiation therapy for cancer of the endometrium. She was strongly suspected to be a case of hereditary nonpolyposis colorectal cancer (HNPCC) due to her clinical manifestations, i.e. metachronous multiple cancer developed in the endometrium and colon. MSI test and immunohistochemistry for mismatch repair (MMR) proteins revealed that MSI was highly positive and expression of hMSH2 was lost in the colon cancers. Further, on examining the genetic change, the point mutation, ACG→ATG, responsible for amino acid change, was detected in codon8 (exon1) of the hMSH2 gene. The change, however, could be a polymorphism of this gene and further analyses were necessitated to confirm the genetic background for HNPCC. Interestingly, three cancers with adenoma were located in the mucosa of radiation colitis, in which several atypical glands were also found. This is the only case of radiation-induced colorectal cancer with MSI-H in our hospital. Because of our previous studies, we believe that the genetic pathway in carcinogenesis of the radiation-induced colon cancer is different from that of HNPCC, despite their having several kinds of clinical and pathological features in common. (author)

Radiation-induced colon cancer with high frequency microsatellite instability (MSI-H), report of a case

Energy Technology Data Exchange (ETDEWEB)

Arai, Masami; Ueno, Masashi; Koizumi, Koichi [Japanese Foundation for Cancer Research, Tokyo (Japan). Hospital] [and others

2002-07-01

We report a 67-year-old female with radiation-induced colon cancer which developed 23 years after radiation therapy for cancer of the endometrium. She was strongly suspected to be a case of hereditary nonpolyposis colorectal cancer (HNPCC) due to her clinical manifestations, i.e. metachronous multiple cancer developed in the endometrium and colon. MSI test and immunohistochemistry for mismatch repair (MMR) proteins revealed that MSI was highly positive and expression of hMSH2 was lost in the colon cancers. Further, on examining the genetic change, the point mutation, ACG{yields}ATG, responsible for amino acid change, was detected in codon8 (exon1) of the hMSH2 gene. The change, however, could be a polymorphism of this gene and further analyses were necessitated to confirm the genetic background for HNPCC. Interestingly, three cancers with adenoma were located in the mucosa of radiation colitis, in which several atypical glands were also found. This is the only case of radiation-induced colorectal cancer with MSI-H in our hospital. Because of our previous studies, we believe that the genetic pathway in carcinogenesis of the radiation-induced colon cancer is different from that of HNPCC, despite their having several kinds of clinical and pathological features in common. (author)

Bone Marrow Cell Therapy on 1,2-Dimethylhydrazine (DMH)-Induced Colon Cancer in Rats.

Science.gov (United States)

El-Khadragy, Manal F; Nabil, Heba M; Hassan, Basmaa N; Tohamy, Amany A; Waaer, Hanaa F; Yehia, Hany M; Alharbi, Afra M; Moneim, Ahmed Esmat Abdel

2018-01-01

Stem cell based therapies are being under focus due to their possible role in treatment of various tumors. Bone marrow stem cells believed to have anticancer potential and are preferred for their activities by stimulating the immune system, migration to the site of tumor and ability for inducting apoptosis in cancer cells. The current study was aimed to investigate the tumor suppressive effects of bone marrow cells (BMCs) in 1,2-dimethylhydrazine (DMH)-induced colon cancer in rats. The rats were randomly allocated into four groups: control, BMCs alone, DMH alone and BMCs with DMH. BMCs were injected intrarectally while DMH was injected subcutaneously at 20 mg/kg body weight once a week for 15 weeks. Histopathological examination and gene expression of survivin, β-catenin and multidrug resistance-1 (MDR-1) by real-time reverse transcription-polymerase chain reaction (RT-PCR) in rat colon tissues. This is in addition to oxidative stress markers in colon were performed across all groups. The presence of aberrant crypt foci was reordered once histopathological examination of colon tissue from rats which received DMH alone. Administration of BMCs into rats starting from zero-day of DMH injection improved the histopathological picture which showed a clear improvement in mucosal layer, few inflammatory cells infiltration periglandular and in the lamina propria. Gene expression in rat colon tissue demonstrated that BMCs down-regulated survivin, β-catenin, MDR-1 and cytokeratin 20 genes expression in colon tissues after colon cancer induction. Amelioration of the colon status after administration of MSCs has been evidenced by a major reduction of lipid peroxidation, nitric oxide, and increasing of glutathione content and superoxide dismutase along with catalase activities. Our findings demonstrated that BMCs have tumor suppressive effects in DMH-induced colon cancer as evidenced by down-regulation of survivin, β-catenin, and MDR-1 genes and enhancing the antioxidant

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.

Saccharomyces boulardii and Candida albicans experimental colonization of the murine gut.

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Samonis, G; Falagas, M E; Lionakis, S; Ntaoukakis, M; Kofteridis, D P; Ntalas, I; Maraki, S

2011-05-01

Saccharomyces boulardii has been and continues to be extensively used as a probiotic, with only rare associations with fungemia. This study evaluated the virulence of this yeast when given as a probiotic, and its role in preventing gastrointestinal (GI) colonization by Candida. Adult male Crl:CD1 (ICR) BR mice were given S. boulardii orally in three different doses or normal saline for 14 days. Stool cultures were performed at the time of discontinuation of yeast administration, as well as 1 and 2 weeks later. Gut colonization was proportional to the given dose but lasted only 1 week and no dissemination of the yeast was detected. S. boulardii was also given for 2 and 4 weeks to mice fed chow containing Candida albicans. S. boulardii in the gut did not affect Candida GI colonization. These findings suggest that oral administration of S. boulardii induces a substantial but short term increase of this yeast in the intestinal lumen and administration of the probiotic does not prevent subsequent GI colonization by C. albicans.

Evaluation of chemopreventive potential of Strobilanthes crispus against colon cancer formation in vitro and in vivo.

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Al-Henhena, Nawal; Khalifa, Shaden A M; Ying, Rozaida Poh Yuen; Ismail, Salmah; Hamadi, Riad; Shawter, Abdrabu N; Idris, Azila Mohd; Azizan, Ainnul; Al-Wajeeh, Nahla Saeed; Abdulla, Mahmood Ameen; El-Seedi, Hesham R

2015-11-25

With cancer being one of the major causes of death around the world, studies are ongoing to find new chemotherapeutic leads. There are common mechanisms for colorectal cancer (CRC) formation. Several are connected with oxidative stress-induced cell apoptosis and others are related to imbalanced homeostasis or intake of drugs/toxins. Plants that have been used for decades in folk and traditional medicine have been accepted as one of the commonest sources of discovered natural agents of cancer chemotherapy and chemoprevention. The aim was to study the antioxidant and chemopreventive effects of Strobilanthes crispus on colorectal cancer formation. Five groups of rats were injected subcutaneously with AOM, 15 mg/kg body weight, each once weekly for 2 weeks. The cancer group was continued on 10 % Tween-20 feeding for 8 weeks. The standard drug group was continued on 35 mg/kg 5-fluorouracil intraperitoneal injection twice a week for 8 weeks, and the experimental groups were continued on 250 and 500 mg/kg S. crispus extract oral feeding for 8 weeks, respectively. The normal group was injected subcutaneously with normal saline once a week for 2 weeks, followed by oral administration of 10 % Tween-20 for 8 weeks. All the rats were sacrificed after 10 weeks. The colons were evaluated grossly and histopathologically for aberrant crypt foci (ACF). Gene expression was performed for Bax, Bcl2, Defa24, Slc24a3, and APC genes by real-time PCR. S. crispus and its fractions were evaluated for their chemopreventive effects against human colorectal adenocarcinoma cell line HT29 and cytotoxicity for normal human colon epithelial cell line CCD 841, and the active fraction was assessed for its components. We observed significant decrease in total colonic ACF formation, malonaldehyde (MDA) and lactate dehydrogenase (LDH), increase in superoxide dismutase (SOD), up-regulation of APC, Bax and Slc24a3, and down-regulation of Defa24 and Bcl-2 in rats treated with Strobilanthes

Black Raspberries Enhance Natural Killer Cell Infiltration into the Colon and Suppress the Progression of Colorectal Cancer

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Pan, Pan; Kang, Siwen; Wang, Youwei; Liu, Ka; Oshima, Kiyoko; Huang, Yi-Wen; Zhang, Jianying; Yearsley, Martha; Yu, Jianhua; Wang, Li-Shu

2017-01-01

Natural killer (NK) cells are an essential component of innate immunity against cancer development. Many studies have been conducted to evaluate immune-modulating effects using dietary compounds. Our laboratory has been investigating the chemopreventive potential of black raspberries (BRBs) and previously demonstrated their beneficial modulation of genetic and epigenetic biomarkers in patients with colorectal cancer (CRC). The current study investigated their potential on modulating NK cells. To avoid the excessive inflammation caused by the dextran sulfate sodium (DSS) treatment that leads to colitis, we treated the mice with overnight DSS so that it would slightly irritate the colon but still promote colon carcinogenesis with 100% incidence in both the ApcMin/+ mice and azoxymethane (AOM)-treated mice. A significant decrease of tissue-infiltrating NK cells along the progression of microadenoma-to-adenoma and adenoma-to-adenocarcinoma was observed in the ApcMin/+/DSS and AOM/DSS mice, respectively. Depletion of NK cells significantly promoted the development of CRC, suggesting a critical role of NK cells in combating CRC progression. BRBs significantly suppressed the CRC progression and increased the number of tissue-infiltrating NK cells in both mouse models. Moreover, we further determined BRBs’ effects on NK cells in the human biopsy specimens collected from our previously completed clinical trial, in which CRC patients consumed BRBs for an average of 4 weeks during a presurgical window. We observed an increased number and an enhanced cytotoxicity of NK cells by BRB intervention. The current study provides evidence that BRBs have the potential to enhance the tumor immunesurveillance of NK cells that can be beneficial in the setting of CRC prevention and treatment. PMID:28861089

The influence of androgens, anti-androgens, and castration on cell proliferation in the jejunal and colonic crypt epithelia, and in dimethylhydrazine-induced adenocarcinoma of rat colon.

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Tutton, P J; Barkla, D H

1982-01-01

Androgenic hormones have previously been shown to promote cell proliferation in the small intestine of rat and androgen receptors have been demonstrated in carcinomata of the large intestine of rat. In this study the influence of testosterone and of castration on epithelial cell proliferation in the small intestine, the large intestine and in dimethylhydrazine-induced colonic tumours is compared. Cell proliferation in the small intestine and in colonic tumours was accelerated by testosterone treatment, and cell proliferation in colonic tumours, but not in the small intestine, was retarded following castration. Cell proliferation in colonic tumours was also inhibited by the anti-androgenic drug, Flutamide. Testosterone and castration each failed to influence cell proliferation in the colonic crypt epithelium of both normal and carcinogen-treated animals.

Gallic acid induced apoptotic events in HCT-15 colon cancer cells

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Subramanian, Aruna Priyadharshni; Jaganathan, Saravana Kumar; Mandal, Mahitosh; Supriyanto, Eko; Muhamad, Ida Idayu

2016-01-01

AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid (GA) against HCT-15 colon cancer cells. METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide (MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species (ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2’,7’-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1. RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase (0.98 ± 1.03 vs 58.01 ± 2.05) with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment. CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells. PMID:27099438

Deoxycholate, an Endogenous Cytotoxin/Geno toxin, Induces the Autophagic Stress-Survival Pathway: Implications for Colon Carcinogenesis

International Nuclear Information System (INIS)

Payne, C.M.; Skillicorn, C.C.; Holubec, H.; Bernstein, C.; Dvorak, K.; Bernstein, H.; Moyer, M.P.; Garewal, H.

2009-01-01

We report that deoxycholate (DOC), a hydrophobic bile acid associated with a high-fat diet, activates the autophagic pathway in non-cancer colon epithelial cells (NCM-460), and that this activation contributes to cell survival. The DOC-induced increase in autophagy was documented by an increase in autophagic vacuoles (detected using transmission electron microscopy, increased levels of LC3-I and LC3-II (western blotting), an increase in acidic vesicles (fluorescence spectroscopy of monodansylcadaverine and lyso tracker red probes), and increased expression of the autophagic protein, beclin-1 (immunohistochemistry/western blotting). The DOC-induced increase in beclin-1 expression was ROS-dependent. Rapa mycin (activator of autophagy) pre-treatment of NCM-460 cells significantly (P<.05) decreased, and 3-MA (inhibitor of autophagy) significantly (P<.05) increased the cell loss caused by DOC treatment, alone. Rapa mycin pre-treatment of the apoptosis-resistant colon cancer cell line, HCT-116RC (developed in our laboratory), resulted in a significant decrease in DOC-induced cell death. Bafilomycin A1 and hydroxychloroquine (inhibitors of the autophagic process) increased the DOC-induced percentage of apoptotic cells in HCT-116RC cells. It was concluded that the activation of autophagy by DOC has important implications for colon carcinogenesis and for the treatment of colon cancer in conjunction with commonly used chemotherapeutic agents.

Effectiveness of EarthTec(®) for killing invasive quagga mussels (Dreissena rostriformis bugensis) and preventing their colonization in the Western United States.

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Watters, Ashlie; Gerstenberger, Shawn L; Wong, Wai Hing

2013-01-01

Quagga mussels (Dreissena rostriformis bugensis) have created economic and ecological impacts in the western United States since their discovery in 2007. This study focuses on chemical control for preventing the spread of these mussels. The effectiveness of EarthTec(®) in killing quagga mussels (adults, juveniles, and veligers) in Lake Mead, Nevada-Arizona, was evaluated over time across six concentrations: 0, 1, 5, 10, 17, and 83 ppm. One hundred percent mortality of adult and juvenile mussels was achieved after 96 h with 17 ppm and 5 ppm (respectively), and 100% veliger mortality occurred within 30 min at 3 ppm. From December 2010 to February 2011, the effectiveness of EarthTec(®) in preventing veliger colonization was also evaluated and the results showed that 2.8 ppm was effective in preventing veliger colonization on fiberglass panels. This study indicates that EarthTec(®) has the potential to be an effective control agent against the invasive quagga mussel, and more specifically, in preventing the colonization of veligers.

Procaine Induces Epigenetic Changes in HCT116 Colon Cancer Cells

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Hussein Sabit

2016-01-01

Full Text Available Colon cancer is the third most commonly diagnosed cancer in the world, and it is the major cause of morbidity and mortality throughout the world. The present study aimed at treating colon cancer cell line (HCT116 with different chemotherapeutic drug/drug combinations (procaine, vorinostat “SAHA,” sodium phenylbutyrate, erlotinib, and carboplatin. Two different final concentrations were applied: 3 μM and 5 μM. Trypan blue test was performed to assess the viability of the cell before and after being treated with the drugs. The data obtained showed that there was a significant decrease in the viability of cells after applying the chemotherapeutic drugs/drug combinations. Also, DNA fragmentation assay was carried out to study the effect of these drugs on the activation of apoptosis-mediated DNA degradation process. The results indicated that all the drugs/drug combinations had a severe effect on inducing DNA fragmentation. Global DNA methylation quantification was performed to identify the role of these drugs individually or in combination in hypo- or hypermethylating the CpG dinucleotide all over the genome of the HCT116 colon cancer cell line. Data obtained indicated that different combinations had different effects in reducing or increasing the level of methylation, which might indicate the effectiveness of combining drugs in treating colon cancer cells.

The nonfermentable dietary fiber lignin alters putative colon cancer risk factors but does not protect against DMH-induced colon cancer in rats.

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Cameron, I L; Hardman, W E; Heitman, D W

1997-01-01

The effect of supplementation of the diet with autohydrolyzed lignin on 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis was studied using 112 male Sprague-Dawley rats. Rats received eight weekly injections of DMH (9.5 mg/kg s.c.) or the saline vehicle solution and then were maintained on a basal AIN-76 fiber-free diet or the basal fiber-free diet plus 5% or 10% (wt/wt) lignin for 24 weeks. Rats were killed 32 weeks after the start of the experiment. Colon tumor incidence, location, and multiplicity were determined. Body weight, caloric intake, fecal dry weight, gut transit time, pH of cecal contents, and total fecal bile acid excretion were measured. Supplementation of the diet with 5% or 10% lignin resulted in increased fecal dry weight and total fecal bile acid excretion and in decreased gut transit time, colon pH, and fecal bile acid concentration. Dietary lignin did not significantly affect colon tumor incidence or multiplicity compared with the fiber-free diet. Thus dietary supplementation with autohydrolyzed lignin, a food fiber with good bulking characteristics, had a significant effect on several factors that have previously been linked to reduction of colon cancer risk, but the consumption of high levels of lignin did not decrease the risk for colon cancer.

Curcumin induces apoptosis and cell cycle arrest via the activation of reactive oxygen species-independent mitochondrial apoptotic pathway in Smad4 and p53 mutated colon adenocarcinoma HT29 cells.

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Agarwal, Ayushi; Kasinathan, Akiladdevi; Ganesan, Ramamoorthi; Balasubramanian, Akhila; Bhaskaran, Jahnavi; Suresh, Samyuktha; Srinivasan, Revanth; Aravind, K B; Sivalingam, Nageswaran

2018-03-01

Curcumin is a natural dietary polyphenol compound that has various pharmacological activities such as antiproliferative and cancer-preventive activities on tumor cells. Indeed, the role reactive oxygen species (ROS) generated by curcumin on cell death and cell proliferation inhibition in colon cancer is poorly understood. In the present study, we hypothesized that curcumin-induced ROS may promote apoptosis and cell cycle arrest in colon cancer. To test this hypothesis, the apoptosis-inducing potential and cell cycle inhibition effect of ROS induced by curcumin was investigated in Smd4 and p53 mutated HT-29 colon adenocarcinoma cells. We found that curcumin treatment significantly increased the level of ROS in HT-29 cells in a dose- and time-dependent manner. Furthermore, curcumin treatment markedly decreased the cell viability and proliferation potential of HT-29 cells in a dose- and time-dependent manner. Conversely, generation of ROS and inhibitory effect of curcumin on HT-29 cells were abrogated by N-acetylcysteine treatment. In addition, curcumin treatment did not show any cytotoxic effects on HT-29 cells. Furthermore, curcumin-induced ROS generation caused the DNA fragmentation, chromatin condensation, and cell nuclear shrinkage and significantly increased apoptotic cells in a dose- and time-dependent manner in HT-29 cells. However, pretreatment of N-acetylcysteine inhibited the apoptosis-triggering effect of curcumin-induced ROS in HT-29 cells. In addition, curcumin-induced ROS effectively mediated cell cycle inhibition in HT-29 cells. In conclusion, our data provide the first evidence that curcumin induces ROS independent apoptosis and cell cycle arrest in colon cancer cells that carry mutation on Smad4 and p53. Copyright © 2018. Published by Elsevier Inc.

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.

MicroRNA214 Is Associated With Progression of Ulcerative Colitis, and Inhibition Reduces Development of Colitis and Colitis-Associated Cancer in Mice.

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Polytarchou, Christos; Hommes, Daniel W; Palumbo, Tiziana; Hatziapostolou, Maria; Koutsioumpa, Marina; Koukos, Georgios; van der Meulen-de Jong, Andrea E; Oikonomopoulos, Angelos; van Deen, Welmoed K; Vorvis, Christina; Serebrennikova, Oksana B; Birli, Eleni; Choi, Jennifer; Chang, Lin; Anton, Peter A; Tsichlis, Philip N; Pothoulakis, Charalabos; Verspaget, Hein W; Iliopoulos, Dimitrios

2015-10-01

Persistent activation of the inflammatory response contributes to the development of inflammatory bowel diseases, which increase the risk of colorectal cancer. We aimed to identify microRNAs that regulate inflammation during the development of ulcerative colitis (UC) and progression to colitis-associated colon cancer (CAC). We performed a quantitative polymerase chain reaction analysis to measure microRNAs in 401 colon specimens from patients with UC, Crohn's disease, irritable bowel syndrome, sporadic colorectal cancer, or CAC, as well as subjects without these disorders (controls); levels were correlated with clinical features and disease activity of patients. Colitis was induced in mice by administration of dextran sodium sulfate (DSS), and carcinogenesis was induced by addition of azoxymethane; some mice also were given an inhibitor of microRNA214 (miR214). A high-throughput functional screen of the human microRNAome found that miR214 regulated the activity of nuclear factor-κB. Higher levels of miR214 were detected in colon tissues from patients with active UC or CAC than from patients with other disorders or controls and correlated with disease progression. Bioinformatic and genome-wide profile analyses showed that miR214 activates an inflammatory response and is amplified through a feedback loop circuit mediated by phosphatase and tensin homolog (PTEN) and PDZ and LIM domain 2 (PDLIM2). Interleukin-6 induced signal transducer and activator of transcription 3 (STAT3)-mediated transcription of miR214. A miR214 chemical inhibitor blocked this circuit and reduced the severity of DSS-induced colitis in mice, as well as the number and size of tumors that formed in mice given azoxymethane and DSS. In fresh colonic biopsy specimens from patients with active UC, the miR214 inhibitor reduced inflammation by increasing levels of PDLIM2 and PTEN. Interleukin-6 up-regulates STAT3-mediated transcription of miR214 in colon tissues, which reduces levels of PDLIM2 and PTEN

Interferon-gamma sensitizes colonic epithelial cell lines to physiological and therapeutic inducers of colonocyte apoptosis.

LENUS (Irish Health Repository)

O'Connell, J

2012-02-03

Homeostasis in the colonic epithelium is achieved by a continuous cycle of proliferation and apoptosis, in which imbalances are associated with disease. Inflammatory bowel disease (IBD) and colon cancer are associated with either excessive or insufficient apoptosis of colonic epithelial cells, respectively. By using two colonic epithelial cell lines, HT29 and SW620, we investigated how the epithelial cell\\'s sensitivity to apoptosis was regulated by the proinflammatory cytokine interferon-gamma (IFN-gamma). We found that IFN-gamma sensitized HT29 cells, and to a lesser extent SW620, to diverse inducers of apoptosis of physiologic or therapeutic relevance to the colon. These apoptosis inducers included Fas (CD95\\/APO-1) ligand (FasL), short-chain fatty acids, and chemotherapeutic drugs. The extent of IFN-gamma-mediated apoptosis sensitization in these two cell lines correlated well with the degree of IFN-gamma-mediated upregulation of the proapoptotic protease caspase-1. Although IFN-gamma alone effectively sensitized HT29 cells to apoptosis, inclusion of the protein synthesis inhibitor cyclohexamide (CHX) during apoptotic challenge was necessary for maximal sensitization of SW620. The requirement of CHX to sensitize SW620 cells to apoptosis implies a need to inhibit translation of antiapoptotic proteins absent from HT29. In particular, the antiapoptotic protein Bcl-2 was strongly expressed in SW620 cells but absent from HT29. Our results indicate that IFN-gamma increases the sensitivity of colonic epithelial cells to diverse apoptotic stimuli in concert, via upregulation of caspase-1. Our findings implicate caspase-1 and Bcl-2 as important central points of control determining the general sensitivity of colonic epithelial cells to apoptosis.

In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

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Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

2015-11-01

We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis. ©2015 American Association for Cancer Research.

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.

Cetuximab-Induced MET Activation Acts as a Novel Resistance Mechanism in Colon Cancer Cells

Directory of Open Access Journals (Sweden)

Na Song

2014-04-01

Full Text Available Aberrant MET expression and hepatocyte growth factor (HGF signaling are implicated in promoting resistance to targeted agents; however, the induced MET activation by epidermal growth factor receptor (EGFR inhibitors mediating resistance to targeted therapy remains elusive. In this study, we identified that cetuximab-induced MET activation contributed to cetuximab resistance in Caco-2 colon cancer cells. MET inhibition or knockdown sensitized Caco-2 cells to cetuximab-mediated growth inhibition. Additionally, SRC activation promoted cetuximab resistance by interacting with MET. Pretreatment with SRC inhibitors abolished cetuximab-mediated MET activation and rendered Caco-2 cells sensitive to cetuximab. Notably, cetuximab induced MET/SRC/EGFR complex formation. MET inhibitor or SRC inhibitor suppressed phosphorylation of MET and SRC in the complex, and MET inhibitor singly led to disruption of complex formation. These results implicate alternative targeting of MET or SRC as rational strategies for reversing cetuximab resistance in colon cancer.

Colon-specific delivery of a probiotic-derived soluble protein ameliorates intestinal inflammation in mice through an EGFR-dependent mechanism

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Yan, Fang; Cao, Hanwei; Cover, Timothy L.; Washington, M. Kay; Shi, Yan; Liu, LinShu; Chaturvedi, Rupesh; Peek, Richard M.; Wilson, Keith T.; Polk, D. Brent

2011-01-01

Probiotic bacteria can potentially have beneficial effects on the clinical course of several intestinal disorders, but our understanding of probiotic action is limited. We have identified a probiotic bacteria–derived soluble protein, p40, from Lactobacillus rhamnosus GG (LGG), which prevents cytokine-induced apoptosis in intestinal epithelial cells. In the current study, we analyzed the mechanisms by which p40 regulates cellular responses in intestinal epithelial cells and p40’s effects on experimental colitis using mouse models. We show that the recombinant p40 protein activated EGFR, leading to Akt activation. Activation of EGFR by p40 was required for inhibition of cytokine-induced apoptosis in intestinal epithelial cells in vitro and ex vivo. Furthermore, we developed a pectin/zein hydrogel bead system to specifically deliver p40 to the mouse colon, which activated EGFR in colon epithelial cells. Administration of p40-containing beads reduced intestinal epithelial apoptosis and disruption of barrier function in the colon epithelium in an EGFR-dependent manner, thereby preventing and treating DSS-induced intestinal injury and acute colitis. Furthermore, p40 activation of EGFR was required for ameliorating colon epithelial cell apoptosis and chronic inflammation in oxazolone-induced colitis. These data define what we believe to be a previously unrecognized mechanism of probiotic-derived soluble proteins in protecting the intestine from injury and inflammation. PMID:21606592

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

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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

Saccharomyces boulardii Protease Inhibits the Effects of Clostridium difficile Toxins A and B in Human Colonic Mucosa

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Castagliuolo, Ignazio; Riegler, Martin F.; Valenick, Leyla; LaMont, J. Thomas; Pothoulakis, Charalabos

1999-01-01

Saccharomyces boulardii is a nonpathogenic yeast used in the treatment of Clostridium difficile diarrhea and colitis. We have reported that S. boulardii inhibits C. difficile toxin A enteritis in rats by releasing a 54-kDa protease which digests the toxin A molecule and its brush border membrane (BBM) receptor (I. Castagliuolo, J. T. LaMont, S. T. Nikulasson, and C. Pothoulakis, Infect. Immun. 64:5225–5232, 1996). The aim of this study was to further evaluate the role of S. boulardii protease in preventing C. difficile toxin A enteritis in rat ileum and determine whether it protects human colonic mucosa from C. difficile toxins. A polyclonal rabbit antiserum raised against purified S. boulardii serine protease inhibited by 73% the proteolytic activity present in S. boulardii conditioned medium in vitro. The anti-protease immunoglobulin G (IgG) prevented the action of S. boulardii on toxin A-induced intestinal secretion and mucosal permeability to [3H]mannitol in rat ileal loops, while control rabbit IgG had no effect. The anti-protease IgG also prevented the effects of S. boulardii protease on digestion of toxins A and B and on binding of [3H]toxin A and [3H]toxin B to purified human colonic BBM. Purified S. boulardii protease reversed toxin A- and toxin B-induced inhibition of protein synthesis in human colonic (HT-29) cells. Furthermore, toxin A- and B-induced drops in transepithelial resistance in human colonic mucosa mounted in Ussing chambers were reversed by 60 and 68%, respectively, by preexposing the toxins to S. boulardii protease. We conclude that the protective effects of S. boulardii on C. difficile-induced inflammatory diarrhea in humans are due, at least in part, to proteolytic digestion of toxin A and B molecules by a secreted protease. PMID:9864230

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.

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.

Mushroom Ganoderma lucidum Prevents Colitis-Associated Carcinogenesis in Mice

Science.gov (United States)

Sliva, Daniel; Loganathan, Jagadish; Jiang, Jiahua; Jedinak, Andrej; Lamb, John G.; Terry, Colin; Baldridge, Lee Ann; Adamec, Jiri; Sandusky, George E.; Dudhgaonkar, Shailesh

2012-01-01

Background Epidemiological studies suggest that mushroom intake is inversely correlated with gastric, gastrointestinal and breast cancers. We have recently demonstrated anticancer and anti-inflammatory activity of triterpene extract isolated from mushroom Ganoderma lucidum (GLT). The aim of the present study was to evaluate whether GLT prevents colitis-associated carcinogenesis in mice. Methods/Principal Findings Colon carcinogenesis was induced by the food-borne carcinogen (2-Amino-1-methyl-6-phenylimidazol[4,5-b]pyridine [PhIP]) and inflammation (dextran sodium sulfate [DSS]) in mice. Mice were treated with 0, 100, 300 and 500 mg GLT/kg of body weight 3 times per week for 4 months. Cell proliferation, expression of cyclin D1 and COX-2 and macrophage infiltration was assessed by immunohistochemistry. The effect of GLT on XRE/AhR, PXR and rPXR was evaluated by the reporter gene assays. Expression of metabolizing enzymes CYP1A2, CYP3A1 and CYP3A4 in colon tissue was determined by immunohistochemistry. GLT treatment significantly suppressed focal hyperplasia, aberrant crypt foci (ACF) formation and tumor formation in mice exposed to PhIP/DSS. The anti-proliferative effects of GLT were further confirmed by the decreased staining with Ki-67 in colon tissues. PhIP/DSS-induced colon inflammation was demonstrated by the significant shortening of the large intestine and macrophage infiltrations, whereas GLT treatment prevented the shortening of colon lengths, and reduced infiltration of macrophages in colon tissue. GLT treatment also significantly down-regulated PhIP/DSS-dependent expression of cyclin D1, COX-2, CYP1A2 and CYP3A4 in colon tissue. Conclusions Our data suggest that GLT could be considered as an alternative dietary approach for the prevention of colitis-associated cancer. PMID:23118901

Akt-dependent NF-κB activation is required for bile acids to rescue colon cancer cells from stress-induced apoptosis

International Nuclear Information System (INIS)

Shant, Jasleen; Cheng, Kunrong; Marasa, Bernard S.; Wang Jianying; Raufman, Jean-Pierre

2009-01-01

Conjugated secondary bile acids promote human colon cancer cell proliferation by activating EGF receptors (EGFR). We hypothesized that bile acid-induced EGFR activation also mediates cell survival by downstream Akt-regulated activation of NF-κB. Deoxycholyltaurine (DCT) treatment attenuated TNF-α-induced colon cancer cell apoptosis, and stimulated rapid and sustained NF-κB nuclear translocation and transcriptional activity (detected by NF-κB binding to an oligonucleotide consensus sequence and by activation of luciferase reporter gene constructs). Both DCT-induced NF-κB nuclear translocation and attenuation of TNF-α-stimulated apoptosis were dependent on EGFR activation. Inhibitors of nuclear translocation, proteosome activity, and IκBα kinase attenuated NF-κB transcriptional activity. Cell transfection with adenoviral vectors encoding a non-degradable IκBα 'super-repressor' blocked the actions of DCT on both NF-κB activation and TNF-α-induced apoptosis. Likewise, transfection with mutant akt and treatment with a chemical inhibitor of Akt attenuated effects of DCT on NF-κB transcriptional activity and TNF-α-induced apoptosis. Chemical inhibitors of Akt and NF-κB activation also attenuated DCT-induced rescue of H508 cells from ultraviolet radiation-induced apoptosis. Collectively, these observations indicate that, downstream of EGFR, bile acid-induced colon cancer cell survival is mediated by Akt-dependent NF-κB activation. These findings provide a mechanism whereby bile acids increase resistance of colon cancer to chemotherapy and radiation

Effectiveness of Bioactive Food Components in Experimental Colon Carcinogenesis

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Emília Hijová

2009-01-01

Full Text Available The aim of the present study was the evaluation of possible protective effects of selected bioactive food components in experimental N,N-dimethylhydrazine (DMH-induced colon carcinogenesis. Wistar albino rats (n = 92 were fed a high fat diet or conventional laboratory diet. Two weeks after the beginning of the trial, DMH injections were given to six groups of rats at the dose of 20 mg/kg b.w. twice weekly. The activity of bacterial enzymes in faeces and serum bile acid concentrations were determined. High fat diet, DMH injections, and their combination significantly increased the activies of β-galactosidase, β-glucuronidase, and α-glucosidase (p p < 0.001, as well as the bile acid concentration compared to the group at the highest risk. The protective effects of selected bioactive food components in experimentally induced colon carcinogenesis allow for their possible use in cancer prevention or treatment.

Dietary fish oil modulates the effect of dimethylhydrazine- induced colon cancer in rats

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Rasmy, G. E.

2011-09-01

Full Text Available This study was conducted to examine the efficacy of fish oil supplementation in male wistar rat colon carcinogenesis. In order to induce colon cancer, the rats were given a weekly subcutaneous injection of 1,2-Dimethylhydrazine (DMH at a dose of 20 mg/kg b.w. for five weeks. Afterwards, some of the rats ingested fish oil for either 4 weeks (DMH-FO4 group, or 17 weeks (DMH-FO17 group. The remaining rats continued without any supplementation for the same 4 weeks (DMH4 group, or 17 weeks (DMH17 group. Another two groups of rats did not receive the DMH and were given fish oil (FO17 group or a normal diet only and considered as the control group (CN group. At the end of the experiment, the rats were sacrificed; and were subsequently subjected to biochemical and molecular biological analyses as well as histopathological examinations. The results showed increased levels of lactate dehydrogenase (LDH, malondialdehyde (MDA and alkaline phoshatase (ALP activities in the DMH rats compared to the control. The liver and colonic changes that were induced by DMH were significantly improved through fish oil supplementation in the DMH-FO17 group. The molecular analysis revealed that DMH treatment induced the expression alterations of genes p53, p27 and p21 and increased DNA band patterns related to cancer, while both FO17 and DMH-FO17 groups showed much better results. A histopathological examination of the DMH17 group revealed colon adenocarcinoma and several lesions in rat liver tissues. An improvement in the histopathological picture was seen in the livers and colons of groups DMHFO17. In conclusion, the present results demonstrated the anti-carciongenic effect of herring fish oil against DMH induced colon carcinogenesis in rats. The inhibitory effect of FO was due to the modulation of elevated biochemical parameters, DNA damage, gene expression and histopathological lesions caused by DMH.

Este estudio fue realizado para examinar la eficacia de la

Effect of Tangweian Jianji on the Biomechanical and Morphometric Remodeling of Colon and Rectum in STZ Induced Diabetic Rats

DEFF Research Database (Denmark)

Sha, Hong; Tong, Xiao-Lin; Liu, Gui-Fang

2012-01-01

.01). Furthermore, the circumferential and longitudinal stiffness of the colonic wall increased in DM group compared those with CON group. TH but not TL treatment could significantly decrease the colonic wall stiffness in both directions (P...AIM: The aim of the study was to investigate the effect of TWAJJ on the biomechanical and morphometrical remodeling of colon and rectum in streptozotocin (STZ) induced diabetic rats. METHODS: The colonic and rectal segments obtained from diabetic (DM), TWAJJ treated diabetic (TH, high dosage: 10 g...

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.

MRSA colonization and infection among persons with occupational livestock exposure in Europe: Prevalence, preventive options and evidence.

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Goerge, Tobias; Lorenz, Marthe Barbara; van Alen, Sarah; Hübner, Nils-Olaf; Becker, Karsten; Köck, Robin

2017-02-01

Colonization with livestock-associated Methicillin-resistant Staphylococcusaureus (LA-MRSA) among persons occupationally exposed to pigs, cattle or poultry is very frequent. In Europe, LA-MRSA mostly belong to the clonal lineage CC398. Since colonized persons have an increased risk of developing MRSA infections, defining the burden of work-related infection caused by LA-MRSA CC398 is of interest to exposed personnel, insurance companies and infection control staff. This review summarizes data on the types of occupation-related infections caused by LA-MRSA CC398, the incidence of such infections as well as potential preventive strategies. We identified twelve case reports on infections among livestock-exposed persons. Overall, there is a lack of data describing the incidence of occupation-related infections due to MRSA CC398. Currently, no specific guidance towards the prevention of LA-MRSA CC398 colonization of persons with routine exposure exists. In vitro, MRSA CC398 strains are susceptible (>95%) to mupirocin. Single reports have described effective decolonization of persons carrying LA-MRSA CC398, but long-term success rates are low in case of continuous livestock contact. Overall, the occupational health risk due to LA-MRSA CC398 is not well understood. Currently, prevention of human LA-MRSA CC398 infection is mostly based on the recommendation to perform screening and decolonization therapies prior to elective medical interventions in order to avoid nosocomial infections, but there is no conclusive evidence to perform specific measures aiming to forestall community-acquired infections. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

Betulin induces cytochrome c release and apoptosis in colon cancer cells via NOXA.

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Zhou, Zhiyuan; Zhu, Chenfang; Cai, Zhongfang; Zhao, Feng; He, Liu; Lou, Xiaolou; Qi, Xiaoliang

2018-05-01

Betulin is a common triterpene that can be readily obtained from various plants, particularly birch trees, in their natural environment. Specific tumor cells are sensitive to betulin, whereas healthy cells are not. Betulin was observed to stimulate programmed cell death of various cancer cell lines; however, the precise molecular mechanism of action of betulin remains unknown. The present study used colon cancer cells, in which mass apoptosis triggered by betulin was identified, and the apoptotic process was demonstrated to occur via the activation of caspase-3 and -9 pathways. In addition, release of cytochrome c was detected. Furthermore, the pro-apoptotic member of the Bcl-2 protein family, NOXA, was induced following treatment with betulin, and the downregulation of NOXA markedly suppressed the release of cytochrome c and apoptosis in colon cancer cells. Conversely, the overexpression of NOXA further enhanced betulin-induced apoptosis. The present study therefore offers novel insights into the mechanism of action of the natural compound betulin against tumors.

Involvement of AMPK signaling cascade in capsaicin-induced apoptosis of HT-29 colon cancer cells.

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Kim, Young Min; Hwang, Jin-Taek; Kwak, Dong Wook; Lee, Yun Kyung; Park, Ock Jin

2007-01-01

Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is activated during ATP-depleting metabolic states, such as hypoxia, heat shock, oxidative stress, and exercise. As a highly conserved heterotrimeric kinase that functions as a major metabolic switch to maintain energy homeostasis, AMPK has been shown to exert as an intrinsic regulator of mammalian cell cycle. Moreover, AMPK cascade has emerged as an important pathway implicated in cancer control. In this article, we have investigated the effects of capsaicin on apoptosis in relation to AMPK activation in colon cancer cell. Capsaicin-induced apoptosis was revealed by the presence of nucleobodies in the capsaicin-treated HT-29 colon cancer cells. Concomitantly, the activation of AMPK and the increased expression of the inactive form of acetyl-CoA carboxylase (ACC) were detected in capsaicin-treated colon cancer cells. We showed that both capsaicin and 5'-aminoimidazole-4-carboxamide-1-beta-D-ribonucleoside (AICAR), an AMPK activator possess the AMPK-activating capacity as well as apoptosis-inducing properties. Evidence of the association between AMPK activation and the increased apoptosis in HT-29 colon cancer cells by capsaicin treatment, and further findings of the correlation of the activated AMPK and the elevated apoptosis by cotreatment of AICAR and capsaicin support AMPK as an important component of apoptosis, as well as a possible target of cancer control.

Post-initiation chlorophyllin exposure does not modulate aflatoxin-induced foci in the liver and colon of rats

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Orner Gayle A

2006-02-01

Full Text Available Abstract Chlorophyllin (CHL is a promising chemopreventive agent believed to block cancer primarily by inhibiting carcinogen uptake through the formation of molecular complexes with the carcinogens. However, recent studies suggest that CHL may have additional biological effects particularly when given after the period of carcinogen treatment. This study examines the post-initiation effects of CHL towards aflatoxin B1 (AFB1-induced preneoplastic foci of the liver and colon. The single concentration of CHL tested in this study (0.1% in the drinking water had no significant effects on AFB1-induced foci of the liver and colons of rats.

The normal bacterial flora prevents GI disease

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. The normal bacterial flora prevents GI disease. Inhibits pathogenic enteric bacteria. Decrease luminal pH; Secrete bacteriocidal proteins; Colonization resistance; Block epithelial binding – induce MUC2. Improves epithelial and mucosal barrier integrity. Produce ...

Chrysin protects against cisplatin-induced colon. toxicity via amelioration of oxidative stress and apoptosis: Probable role of p38MAPK and p53

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Khan, Rehan; Khan, Abdul Quaiyoom; Qamar, Wajhul; Lateef, Abdul; Tahir, Mir; Rehman, Muneeb U; Ali, Farrah; Sultana, Sarwat, E-mail: sarwat786@rediffmail.com

2012-02-01

Cisplatin, an antineoplastic drug, is widely used as a foremost therapy against numerous forms of cancer but it has pronounced adverse effects viz., nephrotoxicity, ototoxicity etc. CDDP-induced emesis and diarrhea are also marked toxicities that may be due to intestinal injury. Chrysin (5,7-dihydroxyflavone), a natural flavone commonly found in many plants possesses multiple biological activities, such as antioxidant, anti-inflammatory and anti-cancer effects. In the present study, we investigated the protective effect of chrysin against CDDP-induced colon toxicity. The plausible mechanism of CDDP-induced colon toxicity and damage includes oxidative stress, activation of p38MAPK and p53, and colonic epithelial cell apoptosis via upregulating the expression of Bak and cleaved caspase-3. Chrysin was administered to Wistar rats once daily for 14 consecutive days at the doses of 25 and 50 mg/kg body weight orally in corn oil. On day 14, a single intraperitoneal injection of cisplatin was given at the dose of 7.5 mg/kg body weight and animals were euthanized after 24 h of cisplatin injection. Chrysin ameliorated CDDP-induced lipid peroxidation, xanthine oxidase activity, glutathione depletion, decrease in antioxidant (catalase, glutathione reductase, glutathione peroxidase and glucose-6 phosphate dehydrogenase) and phase-II detoxifying (glutathione-S-transferase and quinone reductase) enzyme activities. Chrysin also attenuated goblet cell disintegration, expression of phospho-p38MAPK and p53, and apoptotic tissue damage which were induced by CDDP. Histological findings further supported the protective effects of chrysin against CDDP-induced colonic damage. The results of the present study suggest that the protective effect of chrysin against CDDP-induced colon toxicity was related with attenuation of oxidative stress, activation of p38MAPK and p53, and apoptotic tissue damage. Highlights: ► Cisplatin-induced colon toxicity is associated with oxidative stress and

Chrysin protects against cisplatin-induced colon. toxicity via amelioration of oxidative stress and apoptosis: Probable role of p38MAPK and p53

International Nuclear Information System (INIS)

Khan, Rehan; Khan, Abdul Quaiyoom; Qamar, Wajhul; Lateef, Abdul; Tahir, Mir; Rehman, Muneeb U; Ali, Farrah; Sultana, Sarwat

2012-01-01

Cisplatin, an antineoplastic drug, is widely used as a foremost therapy against numerous forms of cancer but it has pronounced adverse effects viz., nephrotoxicity, ototoxicity etc. CDDP-induced emesis and diarrhea are also marked toxicities that may be due to intestinal injury. Chrysin (5,7-dihydroxyflavone), a natural flavone commonly found in many plants possesses multiple biological activities, such as antioxidant, anti-inflammatory and anti-cancer effects. In the present study, we investigated the protective effect of chrysin against CDDP-induced colon toxicity. The plausible mechanism of CDDP-induced colon toxicity and damage includes oxidative stress, activation of p38MAPK and p53, and colonic epithelial cell apoptosis via upregulating the expression of Bak and cleaved caspase-3. Chrysin was administered to Wistar rats once daily for 14 consecutive days at the doses of 25 and 50 mg/kg body weight orally in corn oil. On day 14, a single intraperitoneal injection of cisplatin was given at the dose of 7.5 mg/kg body weight and animals were euthanized after 24 h of cisplatin injection. Chrysin ameliorated CDDP-induced lipid peroxidation, xanthine oxidase activity, glutathione depletion, decrease in antioxidant (catalase, glutathione reductase, glutathione peroxidase and glucose-6 phosphate dehydrogenase) and phase-II detoxifying (glutathione-S-transferase and quinone reductase) enzyme activities. Chrysin also attenuated goblet cell disintegration, expression of phospho-p38MAPK and p53, and apoptotic tissue damage which were induced by CDDP. Histological findings further supported the protective effects of chrysin against CDDP-induced colonic damage. The results of the present study suggest that the protective effect of chrysin against CDDP-induced colon toxicity was related with attenuation of oxidative stress, activation of p38MAPK and p53, and apoptotic tissue damage. Highlights: ► Cisplatin-induced colon toxicity is associated with oxidative stress and

Nutrient Availability Alters the Effect of Autophagy on Sulindac Sulfide-Induced Colon Cancer Cell Apoptosis

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Shiun-Kwei Chiou

2012-01-01

Full Text Available Autophagy is a catabolic process by which a cell degrades its intracellular materials to replenish itself. Induction of autophagy under various cellular stress stimuli can lead to either cell survival or cell death via apoptotic and/or autophagic (nonapoptotic pathways. The NSAID sulindac sulfide induces apoptosis in colon cancer cells. Here, we show that inhibition of autophagy under serum-deprived conditions resulted in significant reductions of sulindac sulfide-induced apoptosis in HT-29 colon cancer cells. In contrast, inhibition of autophagy under conditions where serum is available significantly increased sulindac sulfide-induced apoptosis in HT-29 cells. We previously showed that the apoptosis inhibitor, survivin, plays a role in regulating NSAID-induced apoptosis and autophagic cell death. Here, we show that survivin protein half-life is increased in the presence of autophagy inhibitors under serum-deprived conditions, but not under conditions when serum is available. Thus, the increased levels of survivin may be a factor contributing to inhibition of sulindac sulfide-induced apoptosis under serum-deprived conditions. These results suggest that whether a cell lives or dies due to autophagy induction depends on the balance of factors that regulate both autophagic and apoptotic processes.

Colon preneoplasia after carcinogen exposure is enhanced and colonic serotonergic system is suppressed by food deprivation.

Science.gov (United States)

Kannen, Vinicius; Fernandes, Cleverson R; Stopper, Helga; Zanette, Dalila L; Ferreira, Frederico R; Frajacomo, Fernando T; Carvalho, Milene C; Brandão, Marcus L; Elias Junior, Jorge; Jordão Junior, Alceu Afonso; Uyemura, Sérgio Akira; Waaga-Gasser, Ana Maria; Garcia, Sérgio B

2013-10-04

Calorie restriction regimens usually promote health and extend life-span in mammals. This is partially related to their preventive effects against malignancies. However, certain types of nutritional restriction failed to induce beneficial effects. The American Institute of Nutrition defines calorie restriction as diets which have only 40% fewer calories, but provide normal amounts of necessary food components such as protein, vitamins and minerals; whereas, food restriction means 40% less of all dietary ingredients plus 40% less calories. Our study aimed to test the hypothesis that the latter type of food deprivation (40% less food than consumed by standard fed rats) might increase cancer risk instead of reducing it, as is generally assumed for all dietary restrictive regimens. Since the endogenous modulation of the colon serotonergic system has been observed to play a role during the early steps of carcinogenesis we also investigated whether the serotoninergic system could be involved in the food intake modulation of cancer risk. For this, rats were exposed to a carcinogen and subjected to food deprivation for 56 days. Triglyceride levels and visceral adipose tissue were reduced while hepatic and colonic lipid peroxidation was increased. This dietary restriction also decreased serotonin levels in colon, and gene expression of its intestinal transporter and receptors. Finally, the numbers of preneoplastic lesions in the colon tissue of carcinogen-exposed rats were increased. Our data suggest that food deprivation enhances formation of early tumorigenic lesions by suppressing serotonergic activity in colon tissue. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Beneficial Effects of Anti-Interleukin-6 Antibodies on Impaired Gastrointestinal Motility, Inflammation and Increased Colonic Permeability in a Murine Model of Sepsis Are Most Pronounced When Administered in a Preventive Setup.

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Sara Nullens

Full Text Available During sepsis, gastrointestinal ileus, mucosal barrier dysfunction and bacterial translocation are accepted to be important triggers that can maintain or exacerbate the septic state. In the caecal ligation and puncture animal model of sepsis, we demonstrated that systemic and colonic interleukin-6 levels are significantly increased coinciding with an impaired colonic barrier function. We therefore aimed to study the effect of therapeutic or curative administration of anti-IL6 antibodies on overall GI motility, colonic permeability and translocation of intestinal bacteria in blood and mesenteric lymph nodes in the mouse caecal ligation and puncture model.OF-1 mice were randomized to either the preventive or curative protocol, in which they received 1 mg/kg of antibodies to interleukin-6, or its IgG isotype control solution. They subsequently underwent either the caecal ligation and puncture procedure, or sham-surgery. GI motility was assessed 48 h following the procedure, as well as colonic permeability, serum and colon cytokines, colonic tight junction proteins at the mRNA level; cultures of blood and mesenteric lymph nodes were performed.Preventive administration of anti-interleukin-6 antibodies successfully counteracted the gastrointestinal motility disturbances and impaired colonic barrier function that could be observed in vehicle-treated septic animals. Serum and colonic levels of proinflammatory cytokines were significantly lower when animals were preventively treated with anti-interleukin-6 antibodies. A repetitive injection 24 h later resulted in the most pronounced effects. Curative treatment significantly lowered systemic and colonic inflammation markers while the effects on transit and permeability were unfortunately no longer significant.Caecal ligation and puncture resulted in septic ileus with an increased colonic permeability. Antibodies to interleukin-6 were able to ameliorate gastro-intestinal motility, suppress inflammation and

Chemoprevention of DMH-induced rat colon carcinoma initiation by combination administration of piroxicam and C-phycocyanin.

Science.gov (United States)

Saini, Manpreet Kaur; Vaiphei, Kim; Sanyal, Sankar Nath

2012-02-01

Cancer research illustrated that combinatorial studies can provide significant improvement in safety and effectiveness over the monotherapy regimens. A combination of two drugs may restrain precancerous colon polyps, opening a new possible opportunity for chemoprevention of colon cancer. In this context, chemopreventive efficacy of a combination regimen of C-phycocyanin, a biliprotein present in Spirulina platensis, a cyanobacterium, which is a selective cycloxygenase-2 (COX-2) inhibitor and piroxicam, a traditional non-steroidal anti-inflammatory drug was considered in 1,2 dimethylhyadrazine (DMH)-induced colon carcinogenesis in rats. Western blotting, immunohistochemistry, DNA fragmentation, fluorescent staining, PGE(2) enzyme immunoassay, and carrageenan-induced paw edema test were performed along with morphological and histological analysis. DMH treatment showed a rich presence of preneoplastic lesions such as multiple plaque lesions, aberrant crypt foci, and well-characterized dysplasia. These features were reduced with piroxicam and C-phycocyanin administration. The number of apoptotic cells was featured prominently in all the groups compared with DMH. DMH treatment revealed intact high molecular weight genomic DNA with no signs of laddering/DNA fragmentation while it was noticeable significantly in control and DMH + piroxicam + C-phycocyanin. DMH group showed highest COX-2 expression and PGE(2) level in comparison with other groups. Doses of piroxicam and C-phycocyanin used in the present study were established at an anti-inflammatory range. A combination regimen of piroxicam and C-phycocyanin, rather than individually has the much greater potential for reduction of DMH-induced colon cancer development and COX-2 being the prime possible target in such chemoprevention.

Ampelopsin-induced reactive oxygen species enhance the apoptosis of colon cancer cells by activating endoplasmic reticulum stress-mediated AMPK/MAPK/XAF1 signaling

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Park, Ga Bin; Jeong, Jee-Yeong; Kim, Daejin

2017-01-01

Ampelopsin (Amp) is bioactive natural product and exerts anti-cancer effects against several cancer types. The present study investigated the anti-colon cancer activity of Amp and explored its mechanism of action. The treatment of colon cancer cells with Amp resulted in the dose- and time-dependent induction of apoptosis via the activation of endoplasmic reticulum (ER) stress, 5′ adenosine monophosphate-activated protein kinase (AMPK), and c-Jun N-terminal protein kinase (JNK)/p38 mitogen-activated protein kinases (MAPKs). Salubrinal, an ER stress inhibitor, prevented the upregulation of ER stress-associated proteins, including phosphorylated protein kinase RNA-like ER kinase, phosphorylated eukaryotic translation initiation factor 2α, glucose-regulated protein 78, and CCAAT/enhancer-binding protein homologous protein, as well as suppressing AMPK activation and the MAPK signaling pathway. Knockdown of AMPK by RNA interference failed to block ER stress. Additionally, SP600125 (a JNK inhibitor) and SB203580 (a p38-MAPK inhibitor) effectively inhibited apoptosis and attenuated the expression of X-linked IAP-associated factor 1 (XAF1) and apoptotic Bcl-2 family proteins (BCL2 antagonist/killer 1 and BCL2-associated X protein) in Amp-treated colon cancer cells. Furthermore, reactive oxygen species (ROS)-mediated ER stress/AMPK apoptotic signaling pathway in Amp-treated colon cancer cells were markedly inhibited by treatment with N-acetyl-L-cysteine, a ROS scavenger. These results demonstrate that treatment with Amp induces the apoptotic death of colon cancer cells through ER stress-initiated AMPK/MAPK/XAF1 signaling. These results also provide experimental information for developing Amp as therapeutic drug against colon cancer. PMID:29250183

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

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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.

The Effect of Sulfated (1→3-α-l-Fucan from the Brown Alga Saccharina cichorioides Miyabe on Resveratrol-Induced Apoptosis in Colon Carcinoma Cells

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Olesia S. Vishchuk

2013-01-01

Full Text Available Accumulating data clearly indicate that the induction of apoptosis by nontoxic natural compounds is a potent defense against the development and progression of many malignancies, including colon cancer. Resveratrol and the fucoidans have been shown to possess potent anti-tumor activity in vitro and in vivo. The aim of the present study was to examine whether the combination of a fucoidan from the brown alga Saccharina cichorioides Miyabe and resveratrol would be an effective preventive and/or therapeutic strategy against colon cancer. Based on NMR spectroscopy and MALDI-TOF analysis, the fucoidan isolated and purified from Saccharina cichorioides Miyabe was (1→3-α-l-fucan with sulfate groups at C2 and C4 of the α-l-fucopyranose residues. The fucoidan enhanced the antiproliferative activity of resveratrol at nontoxic doses and facilitated resveratrol-induced apoptosis in the HCT 116 human colon cancer cell line. Apoptosis was realized by the activation of initiator caspase-9 and effector caspase-7 and -3, followed by the cleavage of PARP. Furthermore, significant inhibition of HCT 116 colony formation was associated with the sensitization of cells to resveratrol by the fucoidan. Taken together, these results demonstrate that the combination of the algal fucoidan with resveratrol may provide a potential therapy against human colon cancer.

Electrocautery-induced localized colonic injury elicits increased levels of pro-inflammatory cytokines in small bowel and decreases jejunal alanine absorption.

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Barada, Kassem; Mourad, Fadi H; Noutsi, Bakiza; Saadé, Nayef E

2015-01-01

Colitis is associated with functional abnormalities in proximal non-inflamed gut areas, but animal models to study small bowel dysfunction in colitis have limitations. This study aims to determine small intestinal alanine absorption and cytokine expression in a novel model of colonic ulceration induced by electro-cautery. A descending colon ulcer was induced in rats by a bipolar electro-cautery probe. Ulcer score was determined using Satoh's criteria. Jejunal alanine absorption was measured immediately and at different time intervals post ulcer induction. Levels of interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) protein and m-RNA were determined in mucosal scrapings obtained from the colon, duodenum, jejunum and ileum at various time intervals after colonic ulcer induction. The mean ulcer score was 3 up to 48h, followed by healing by 96h post ulcer induction. Small bowel histology was normal throughout. Jejunal alanine absorption was reduced by 12-34% immediately and up to 72h after cautery and returned to normal at 96h. IL-1 and TNF-α mRNA increased significantly in the colon, duodenum, jejunum and ileum 3h post electro-cautery and returned to normal at 48h, while that of IL-6 increased significantly at 48h post ulcer induction. Similarly, IL-1, IL-6 and TNF-α protein levels increased in the duodenum, jejunum, ileum and colon up to 48h post ulcer induction. Electrically induced localized colonic injury increased production of pro-inflammatory cytokines in non-inflamed segments of the small intestine and was associated with derangements of jejunal absorptive function. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

Comparison between oral antibiotics and probiotics as bowel preparation for elective colon cancer surgery to prevent infection: prospective randomized trial.

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Sadahiro, Sotaro; Suzuki, Toshiyuki; Tanaka, Akira; Okada, Kazutake; Kamata, Hiroko; Ozaki, Toru; Koga, Yasuhiro

2014-03-01

We have already reported that, for patients undergoing elective colon cancer operations, perioperative infection can be prevented by a single intravenous dose of an antibiotic given immediately beforehand if mechanical bowel preparation and the administration of oral antibiotics are implemented. Synbiotics has been reported to reduce the rate of infection in patients after pancreatic cancer operations. The effectiveness of oral antibiotics and probiotics in preventing postoperative infection in elective colon cancer procedures was examined in a randomized controlled trial. Three hundred ten patients with colon cancer randomly were assigned to one of three groups. All patients underwent mechanical bowel preparation and received a single intravenous dose of flomoxef immediately before operation. Probiotics were administered in Group A; oral antibiotics were administered in Group B; and neither probiotics nor oral antibiotics were administered in Group C. Stool samples were collected 9 and 2 days before and 7 and 14 days after the procedure. Clostridium difficile toxin and the number of bacteria in the intestine were determined. The rates of incisional surgical-site infection were 18.0%, 6.1%, and 17.9% in Groups A, B, and C, and the rates of leakage were 12.0%, 1.0%, and 7.4% in Groups A, B, and C, respectively, indicating that both rates were lesser in Group B than in Groups A and C (P = .014 and P = .004, respectively). The detection rates of C. difficile toxin were not changed among the three groups. We recommend oral antibiotics, rather than probiotics, as bowel preparation for elective colon cancer procedures to prevent surgical-site infections. Copyright © 2014 Mosby, Inc. All rights reserved.

Piriformospora indica root colonization triggers local and systemic root responses and inhibits secondary colonization of distal roots.

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Pedrotti, Lorenzo; Mueller, Martin J; Waller, Frank

2013-01-01

Piriformosporaindica is a basidiomycete fungus colonizing roots of a wide range of higher plants, including crop plants and the model plant Arabidopsis thaliana. Previous studies have shown that P. indica improves growth, and enhances systemic pathogen resistance in leaves of host plants. To investigate systemic effects within the root system, we established a hydroponic split-root cultivation system for Arabidopsis. Using quantitative real-time PCR, we show that initial P. indica colonization triggers a local, transient response of several defense-related transcripts, of which some were also induced in shoots and in distal, non-colonized roots of the same plant. Systemic effects on distal roots included the inhibition of secondary P. indica colonization. Faster and stronger induction of defense-related transcripts during secondary inoculation revealed that a P. indica pretreatment triggers root-wide priming of defense responses, which could cause the observed reduction of secondary colonization levels. Secondary P. indica colonization also induced defense responses in distant, already colonized parts of the root. Endophytic fungi therefore trigger a spatially specific response in directly colonized and in systemic root tissues of host plants.

PROMOTION OF TRIHALOMETHANE-INDUCED COLON, ABERRANT CRYPT FOCI (ACF) BY A HIGH FAT DIET

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Abstract:Bromodichloromethane (BOCM) and tribromomethane (TBM) enhanced neoplasia in the large intestine of rats when given by corn oil gavage; BOCM in the drinking water to male rats did not induce colon tumors, but did increase liver tumors. However, TBM and a mixture o...

Effect of Saccharomyces Boulardii Cell Wall Extracts on Colon Cancer Prevention in Male F344 Rats Treated with 1,2-Dimethylhydrazine.

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Fortin, Olivier; Aguilar-Uscanga, Blanca R; Vu, Khanh D; Salmieri, Stephane; Lacroix, Monique

2018-01-01

The effect of Saccharomyces boulardii cell wall extracts on colon cancer prevention in rats treated with 1,2-dimethylhydrazine was investigated. A crude insoluble glucan (0.5 and 1.0 mg/kg/day) and a crude mannoprotein extract (0.3 and 3.0 mg/kg/day) were administered in rats by gavage for 12 weeks along with a high fat low fiber diet whereupon rats were sacrificed and aberrant crypt foci (ACF) were counted in the colon. Moreover, NAD(P)H: quinone reductase (QR) and harmful fecal enzymes (β-glucosidase and β-glucuronidase) were quantified in the liver and in the caecum, respectively. Results showed a reduction in ACF counts, a decreased β-glucuronidase activity and an increased QR activity when rats were treated only with insoluble glucan. While these enzymatic modulations may be constituted one of the mechanisms that is responsible for the reduction of ACF counts observed, the reduction of ACF counts caused by insoluble glucan should be addressed, at least, as a biomarker of their cancer-prevention properties. To our knowledge, this is the first study demonstrated that crude cell wall extract obtained from S. boulardii could have a potential role in colon cancer prevention in vivo by revealing the potential implication of QR and β-glucuronidase modulation.

ERβ-dependent neuroglobin up-regulation impairs 17β-estradiol-induced apoptosis in DLD-1 colon cancer cells upon oxidative stress injury.

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Fiocchetti, Marco; Camilli, Giulia; Acconcia, Filippo; Leone, Stefano; Ascenzi, Paolo; Marino, Maria

2015-05-01

Besides other mechanism(s) 17β-estradiol (E2) facilitates neuronal survival by increasing, via estrogen receptor β (ERβ), the levels of neuroglobin (NGB) an anti-apoptotic protein. In contrast, E2 could exert protective effects in cancer cells by activating apoptosis when the ERβ level prevails on that of ERα as in colon cancer cell lines. These apparently contrasting results raise the possibility that E2-induced NGB up-regulation could regulate the ERβ activities shunning this receptor subtype to trigger an apoptotic cascade in neurons but not in non-neuronal cells. Here, human colorectal adenocarcinoma cell line (DLD-1) that only expresses ERβ and HeLa cells transiently transfected with ERβ encoding vector has been used to verify this hypothesis. In addition, neuroblastoma SK-N-BE cells were used as positive control. Surprisingly, E2 also induced NGB up-regulation, in a dose- and time-dependent manner, in DLD-1 cells. The ERβ-mediated activation of p38/MAPK was necessary for this E2 effect. E2 induced NGB re-allocation in mitochondria where, subsequently to an oxidative stress injury (i.e., 100μM H2O2), NGB interacted with cytochrome c preventing its release into the cytosol and the activation of an apoptotic cascade. As a whole, these results demonstrate that E2-induced NGB up-regulation could act as an oxidative stress sensor, which does not oppose to the pro-apoptotic E2 effect in ERβ-containing colon cancer cells unless a rise of oxidative stress occurs. These results support the concept that oxidative stress plays a critical role in E2-induced carcinogenesis and further open an important scenario to develop novel therapeutic strategies that target NGB against E2-related cancers. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Multiepitope Fusion Antigen Induces Broadly Protective Antibodies That Prevent Adherence of Escherichia coli Strains Expressing Colonization Factor Antigen I (CFA/I), CFA/II, and CFA/IV

OpenAIRE

Ruan, Xiaosai; Knudsen, David E.; Wollenberg, Katie M.; Sack, David A.; Zhang, Weiping

2014-01-01

Diarrhea is the second leading cause of death in children younger than 5 years and continues to be a major threat to global health. Enterotoxigenic Escherichia coli (ETEC) strains are the most common bacteria causing diarrhea in developing countries. ETEC strains are able to attach to host small intestinal epithelial cells by using bacterial colonization factor antigen (CFA) adhesins. This attachment helps to initiate the diarrheal disease. Vaccines that induce antiadhesin immunity to block a...

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

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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

CD73 Is Critical for the Resolution of Murine Colonic Inflammation

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Margaret S. Bynoe

2012-01-01

Full Text Available CD73 is a glycosyl-phosphatidylinositol-(GPI- linked membrane protein that catalyzes the extracellular dephosphorylation of adenosine monophosphate (AMP to adenosine. Adenosine is a negative regulator of inflammation and prevents excessive cellular damage. We investigated the role of extracellular adenosine in the intestinal mucosa during the development of Dextran-Sulfate-Sodium-(DSS-salt-induced colitis in mice that lack CD73 (CD73−/− and are unable to synthesize extracellular adenosine. We have found that, compared to wild-type (WT mice, CD73−/− mice are highly susceptible to DSS-induced colitis. CD73−/− mice exhibit pronounced weight loss, slower weight recovery, an increase in gut permeability, a decrease in expression of tight junctional adhesion molecules, as well as unresolved inflammation following the removal of DSS. Moreover, colonic epithelia in CD73−/− mice exhibited increased TLR9 expression, high levels of IL-1β and TNF-α, and constitutive activation of NF-κB. We conclude that CD73 expression in the colon is critical for regulating the magnitude and the resolution of colonic immune responses.

Prevention and Treatment of Noise-Induced Tinnitus

Science.gov (United States)

2014-09-01

Tinnitus PRINCIPAL INVESTIGATOR: Dr. Richard A. Altschuler CONTRACTING ORGANIZATION: University of Michigan REPORT DATE: 2014...3 Ju 2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Prevention and Treatment of Noise-Induced Tinnitus 5b. GRANT NUMBER 5c. PROGRAM...prevent or treat noise induced tinnitus . Our studies showed a military relevant small arms fire-like noise will induce tinnitus in approximately 33

Preventive and therapeutic effects of blueberry (Vaccinium corymbosum) extract against DSS-induced ulcerative colitis by regulation of antioxidant and inflammatory mediators.

Science.gov (United States)

Pervin, Mehnaz; Hasnat, Md Abul; Lim, Ji-Hong; Lee, Yoon-Mi; Kim, Eun Ok; Um, Byung-Hun; Lim, Beong Ou

2016-02-01

Inflammatory bowel disease (IBD) is an inflammatory disorder caused by hyperactivation of effector immune cells that produce high levels of proinflammatory cytokines. The aims of our study were to determine whether orally administered blueberry extract (BE) could attenuate or prevent the development of experimental colitis in mice and to elucidate the mechanism of action. Female Balb/C mice (n=7) were randomized into groups differing in treatment conditions (prevention and treatment) and dose of BE (50 mg/kg body weight). Acute ulcerative colitis was induced by oral administration of 3% dextran sodium sulfate for 7 days in drinking water. Colonic mucosal injury was assessed by clinical, macroscopic, biochemical and histopathological examinations. BE significantly decreased disease activity index and improved the macroscopic and histological score of colons when compared to the colitis group (P<.05). BE markedly attenuated myeloperoxidase accumulation (colitis group 54.97±2.78 nmol/mg, treatment group 30.78±1.33 nmol/mg) and malondialdehyde in colon and prostaglandin E2 level in serum while increasing the levels of superoxide dismutase and catalase (colitis group 11.94±1.16 U/ml, BE treatment group 16.49±0.39 U/ml) compared with the colitis group (P<.05). mRNA levels of the cyclooxygenase (COX)-2, interferon-γ, interleukin (IL)-1β and inducible nitric oxide synthase cytokines were determined by reverse transcriptase polymerase chain reaction. Immunohistochemical analysis showed that BE attenuates the expression of COX-2 and IL-1β in colonic tissue. Moreover, BE reduced the nuclear translocation of nuclear transcription factor kappa B (NF-κB) by immunofluorescence analysis. Thus, the anti-inflammatory effect of BE at colorectal sites is a result of a number of mechanisms: antioxidation, down-regulation of the expression of inflammatory mediators and inhibition of the nuclear translocation of NF-κB. Copyright © 2015 Elsevier Inc. All rights reserved.

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

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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.

In vitro study of acetylcholine and histamine induced contractions in colon and rectum of adult and neonate rats.

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Singh, Shuchita; Mandal, Maloy B

2013-01-01

Contractile mechanisms of different parts of the gut in adult and neonate may not be identical due to developmental processes. The present study was undertaken to investigate acetylcholine (ACh) and histamine induced contractile responses of colon and rectum in adult and neonatal albino rats. Contractile responses were recorded from isolated in vitro preparations. The dose-response curve for ACh (0.001-100 microM) revealed dose dependent increase in contractile responses. A significantly (P pheniramine (100 microM) in adult rectum. This potentiating response of pheniramine was absent in neonate rectum. Such effect was also not seen in colon of both adult and neonate. The present investigation indicates that the contractile responses induced by ACh are similar in both adult and neonate, excepting that the blocking effect of atropine in colon was more pronounced in adult as compared to neonate. Further, the results also indicated different mechanism of histamine action in adults and neonates as evidenced by the significant enhancement of contractions by pheniramine only in adult rectum. Therefore, the present results indicate the existence of a different cholinergic and histaminergic activity in adult and neonate as well as in rectal and colonic tissue.

Exosomes promote cetuximab resistance via the PTEN/Akt pathway in colon cancer cells.

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Zhang, S; Zhang, Y; Qu, J; Che, X; Fan, Y; Hou, K; Guo, T; Deng, G; Song, N; Li, C; Wan, X; Qu, X; Liu, Y

2017-11-13

Cetuximab is widely used in patients with metastatic colon cancer expressing wildtype KRAS. However, acquired drug resistance limits its clinical efficacy. Exosomes are nanosized vesicles secreted by various cell types. Tumor cell-derived exosomes participate in many biological processes, including tumor invasion, metastasis, and drug resistance. In this study, exosomes derived from cetuximab-resistant RKO colon cancer cells induced cetuximab resistance in cetuximab-sensitive Caco-2 cells. Meanwhile, exosomes from RKO and Caco-2 cells showed different levels of phosphatase and tensin homolog (PTEN) and phosphor-Akt. Furthermore, reduced PTEN and increased phosphorylated Akt levels were found in Caco-2 cells after exposure to RKO cell-derived exosomes. Moreover, an Akt inhibitor prevented RKO cell-derived exosome-induced drug resistance in Caco-2 cells. These findings provide novel evidence that exosomes derived from cetuximab-resistant cells could induce cetuximab resistance in cetuximab-sensitive cells, by downregulating PTEN and increasing phosphorylated Akt levels.

Effect of Chang Run Tong on the Biomechanical and Morphometric Remodeling of Colon and Rectum in STZ Induced Diabetic Rats

DEFF Research Database (Denmark)

Sha, Hong; Zhao, Dong; Zhao, Jingbo

2013-01-01

The present study investigates the effect of Chang Run Tong (CRT) on the biomechanical and morphometrical remodeling of colon and rectum in streptozotocin-induced diabetic rats. The colonic and rectal segments were obtained from diabetic (DM), CRT-treated diabetic (T1, high dosage: 50 g/kg/day; T2...

Levodopa acts centrally to induce an antinociceptive action against colonic distension through activation of D2 dopamine receptors and the orexinergic system in the brain in conscious rats

Directory of Open Access Journals (Sweden)

Toshikatsu Okumura

2016-02-01

Subcutaneously (80 mg/rat or intracisternally (2.5 μg/rat administered levodopa significantly increased the threshold of colonic distension-induced AWR in conscious rats. The dose difference to induce the antinociceptive action suggests levodopa acts centrally to exert its antinociceptive action against colonic distension. While neither sulpiride, a D2 dopamine receptor antagonist, nor SCH23390, a D1 dopamine receptor antagonist by itself changed the threshold of colonic distension-induced AWR, the intracisternally injected levodopa-induced antinociceptive action was significantly blocked by pretreatment with subcutaneously administered sulpiride but not SCH23390. Treatment with intracisternal SB334867, an orexin 1 receptor antagonist, significantly blocked the subcutaneously administered levodopa-induced antinociceptive action. These results suggest that levodopa acts centrally to induce an antinociceptive action against colonic distension through activation of D2 dopamine receptors and the orexinergic system in the brain.

Haemophilus influenzae from Patients with Chronic Obstructive Pulmonary Disease Exacerbation Induce More Inflammation than Colonizers

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Chin, Cecilia L.; Manzel, Lori J.; Lehman, Erin E.; Humlicek, Alicia L.; Shi, Lei; Starner, Timothy D.; Denning, Gerene M.; Murphy, Timothy F.; Sethi, Sanjay; Look, Dwight C.

2005-01-01

Rationale: Airway infection with Haemophilus influenzae causes airway inflammation, and isolation of new strains of this bacteria is associated with increased risk of exacerbations in patients with chronic obstructive pulmonary disease (COPD). Objective: To determine whether strains of H. influenzae associated with exacerbations cause more inflammation than strains that colonize the airways of patients with COPD. Methods: Exacerbation strains of H. influenzae were isolated from patients during exacerbation of clinical symptoms with subsequent development of a homologous serum antibody response and were compared with colonization strains that were not associated with symptom worsening or an antibody response. Bacterial strains were compared using an in vivo mouse model of airway infection and in vitro cell culture model of bacterial adherence and defense gene and signaling pathway activation in primary human airway epithelial cells. Results: H. influenzae associated with exacerbations caused more airway neutrophil recruitment compared with colonization strains in the mouse model of airway bacterial infection. Furthermore, exacerbation strains adhered to epithelial cells in significantly higher numbers and induced more interleukin-8 release after interaction with airway epithelial cells. This effect was likely mediated by increased activation of the nuclear factor-κB and p38 mitogen-activated protein kinase signaling pathways. Conclusions: The results indicate that H. influenzae strains isolated from patients during COPD exacerbations often induce more airway inflammation and likely have differences in virulence compared with colonizing strains. These findings support the concept that bacteria infecting the airway during COPD exacerbations mediate increased airway inflammation and contribute to decreased airway function. PMID:15805181

Treatment of diverticular disease of the colon and prevention of acute diverticulitis: a systematic review.

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Maconi, Giovanni; Barbara, Giovanni; Bosetti, Cristina; Cuomo, Rosario; Annibale, Bruno

2011-10-01

Diverticular disease of the colon is a common disorder, characterized by recurrent symptoms and complications such as diverticulitis, requiring hospital admissions and surgery. This study aimed to systematically review the evidence for medical therapy of diverticular disease in reducing symptoms and preventing acute diverticulitis. MEDLINE and Embase databases (1966 to February 2010). The studies selected were prospective clinical trials on uncomplicated diverticular disease of the colon. Four investigators independently reviewed articles, extracted data, and assessed study quality according to standardized criteria. The main outcomes measured were improvement in symptoms, complete remission of symptoms, and prevention of acute diverticulitis. We identified 31 studies, including 6 placebo-controlled trials. The methodological quality of these studies was suboptimal. Only 10 trials provided a detailed description of the patient history, 8 assessed symptoms by the use of a validated questionnaire, and 14 appropriately defined inclusion and exclusion criteria. Only one long-term double-blind placebo-controlled study was identified. This reported a significant improvement in symptoms and greater prevalence of symptom-free patients at 1 year with fiber plus rifaximin in comparison with fiber alone. The efficacy of treatment in preventing acute diverticulitis was evaluated in 11 randomized trials. Four trials compared rifaximin plus fiber vs fiber alone and failed to show a significant difference between treatments. However, cumulative data from these trials revealed a significant benefit following rifaximin and fiber (1-year rate of acute diverticulitis: 11/970 (1.1%) vs 20/690 (2.9%); P = .012), but with a number needed to treat of 57, to prevent an attack of acute diverticulitis. : Heterogeneity of the study design, patients' characteristics, regimens and combination of studied treatment, and outcome reporting precluded the pooling of results and limited

Synbiotic preparation with Lactic acid bacteria and inulin as a functional food: In vivo evaluation of microbial activities, and preneoplastic aberrant crypt foci

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Chaiyavat CHAIYASUT

Full Text Available Abstract Host microbiome and metabolome are associated with the incidence of colorectal cancer (CC, one of the major health problems in developed countries. The pro and prebiotic supplementation helps to improve the host health. Inulin is one such prebiotic used for the enhancement of naïve probiotic bacterial population. This paper explains the impact of inulin (PRE extracted from Jerusalem artichoke (JA, Lactobacillus plantarum HII11 (PRO, and synbiotic (SYN; inulin + L. plantarum HII11 preparation on Azoxymethane mediated CC induced rat model with respect to changes in microbial load, microbial enzymes, and preneoplastic aberrant crypt foci. The results suggested that the PRE and SYN supplementation effectively reduced the selected pathogenic bacteria (Salmonella spp., and Escherichia coli, microbial enzymes and increased the probiotic load. The intervention of SYN significantly reduced the colonic ACF in CC model. The study results revealed that the supplementation of SYN diet (inulin and L. plantarum HII11 protects the AOM-mediated colon cancer induced host.

Boletus edulis biologically active biopolymers induce cell cycle arrest in human colon adenocarcinoma cells.

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Lemieszek, Marta Kinga; Cardoso, Claudia; Ferreira Milheiro Nunes, Fernando Hermínio; Ramos Novo Amorim de Barros, Ana Isabel; Marques, Guilhermina; Pożarowski, Piotr; Rzeski, Wojciech

2013-04-25

The use of biologically active compounds isolated from edible mushrooms against cancer raises global interest. Anticancer properties are mainly attributed to biopolymers including mainly polysaccharides, polysaccharopeptides, polysaccharide proteins, glycoproteins and proteins. In spite of the fact that Boletus edulis is one of the widely occurring and most consumed edible mushrooms, antitumor biopolymers isolated from it have not been exactly defined and studied so far. The present study is an attempt to extend this knowledge on molecular mechanisms of their anticancer action. The mushroom biopolymers (polysaccharides and glycoproteins) were extracted with hot water and purified by anion-exchange chromatography. The antiproliferative activity in human colon adenocarcinoma cells (LS180) was screened by means of MTT and BrdU assays. At the same time fractions' cytotoxicity was examined on the human colon epithelial cells (CCD 841 CoTr) by means of the LDH assay. Flow cytometry and Western blotting were applied to cell cycle analysis and protein expression involved in anticancer activity of the selected biopolymer fraction. In vitro studies have shown that fractions isolated from Boletus edulis were not toxic against normal colon epithelial cells and in the same concentration range elicited a very prominent antiproliferative effect in colon cancer cells. The best results were obtained in the case of the fraction designated as BE3. The tested compound inhibited cancer cell proliferation which was accompanied by cell cycle arrest in the G0/G1-phase. Growth inhibition was associated with modulation of the p16/cyclin D1/CDK4-6/pRb pathway, an aberration of which is a critical step in the development of many human cancers including colon cancer. Our results indicate that a biopolymer BE3 from Boletus edulis possesses anticancer potential and may provide a new therapeutic/preventive option in colon cancer chemoprevention.

Curcumin synergizes with resveratrol to inhibit colon cancer.

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Majumdar, Adhip P N; Banerjee, Sanjeev; Nautiyal, Jyoti; Patel, Bhaumik B; Patel, Vaishali; Du, Jianhua; Yu, Yingjie; Elliott, Althea A; Levi, Edi; Sarkar, Fazlul H

2009-01-01

Development and progression of many malignancies, including colorectal cancer, are associated with activation of multiple signaling pathways. Therefore, inhibition of these signaling pathways with noncytotoxic natural products represents a logical preventive and/or therapeutic approach for colon cancer. Curcumin and resveratrol, both of which inhibit the growth of transformed cells and colon carcinogenesis, were selected to examine whether combining them would be an effective preventive and/or therapeutic strategy for colon cancer. Indeed, the combination of curcumin and resveratrol was found to be more effective in inhibiting growth of p53-positive (wt) and p53-negative colon cancer HCT-116 cells in vitro and in vivo in SCID xenografts of colon cancer HCT-116 (wt) cells than either agent alone. Analysis by Calcusyn software showed synergism between curcumin and resveratrol. The inhibition of tumors in response to curcumin and/or resveratrol was associated with the reduction in proliferation and stimulation of apoptosis accompanied by attenuation of NF-kappaB activity. In vitro studies have further demonstrated that the combinatorial treatment caused a greater inhibition of constitutive activation of EGFR and its family members as well as IGF-1R. Our current data suggest that the combination of curcumin and resveratrol could be an effective preventive/therapeutic strategy for colon cancer.

The inflammatory mediator leukotriene D4 induces subcellular β-catenin translocation and migration of colon cancer cells

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Salim, Tavga; Sand-Dejmek, Janna; Sjölander, Anita

2014-01-01

The abnormal activation of the Wnt/β-catenin pathway frequently occurs in colorectal cancer. The nuclear translocation of β-catenin activates the transcription of target genes that promote cell proliferation, survival, and invasion. The pro-inflammatory mediator leukotriene D 4 (LTD 4 ) exerts its effects through the CysLT 1 receptor. We previously reported an upregulation of CysLT 1 R in patients with colon cancer, suggesting the importance of leukotrienes in colon cancer. The aim of this study was to investigate the impact of LTD 4 on Wnt/β-catenin signaling and its effects on proliferation and migration of colon cancer cells. LTD 4 stimulation led to an increase in β-catenin expression, β-catenin nuclear translocation and the subsequent transcription of MYC and CCND1. Furthermore, LTD 4 significantly reduced the expression of E-cadherin and β-catenin at the plasma membrane and increased the migration and proliferation of HCT116 colon cancer cells. The effects of LTD 4 can be blocked by the inhibition of CysLT 1 R. Furthermore, LTD 4 induced the inhibition of glycogen synthase kinase 3 (GSK)-3β activity, indicating a crosstalk between the G-protein-coupled receptor CysLT 1 and the Wnt/β-catenin pathway. In conclusion, LTD 4 , which can be secreted from macrophages and leukocytes in the tumor microenvironment, induces β-catenin translocation and the activation of β-catenin target genes, resulting in the increased proliferation and migration of colon cancer cells. - Highlights: • Leukotriene D 4 (LTD 4 ) lowers membrane β-catenin but increases nuclear β-catenin levels in colon cancer cells. • In agreement, LTD 4 triggers inactivation of GSK-3β, activation of TCF/LEF and increased expression of Cyclin D1 and c-Myc. • LTD 4 also caused a significant reduction in the expression of E-cadherin and an increased migration of colon cancer cells

Origin of Somatic Mutations in β-Catenin versus Adenomatous Polyposis Coli in Colon Cancer: Random Mutagenesis in Animal Models versus Nonrandom Mutagenesis in Humans.

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Yang, Da; Zhang, Min; Gold, Barry

2017-07-17

Wnt signaling is compromised early in the development of human colorectal cancer (CRC) due to truncating nonsense mutations in adenomatous polyposis coli (APC). CRC induced by chemical carcinogens, such as heterocyclic aromatic amines and azoxymethane, in mice also involves dysregulation of Wnt signaling but via activating missense mutations in the β-catenin oncogene despite the fact that genetically modified mice harboring an inactive APC allele efficiently develop CRC. In contrast, activating mutations in β-catenin are rarely observed in human CRC. Dysregulation of the Wnt signaling pathway by the two distinct mechanisms reveals insights into the etiology of human CRC. On the basis of calculations related to DNA adduct levels produced in mouse CRC models using mutagens, and the number of stem cells in the mouse colon, we show that two nonsense mutations required for biallelic disruption of APC are statistically unlikely to produce CRC in experiments using small numbers of mice. We calculate that an activating mutation in one allele near the critical GSK3β phosphorylation site on β-catenin is >10 5 -times more likely to produce CRC by random mutagenesis due to chemicals than inactivating two alleles in APC, yet it does not occur in humans. Therefore, the mutagenesis mechanism in human CRC cannot be random. We explain that nonsense APC mutations predominate in human CRC because of deamination at 5-methylcytosine at CGA and CAG codons, coupled with the number of human colonic stem cells and lifespan. Our analyses, including a comparison of mutation type and age at CRC diagnosis in U.S. and Chinese patients, also indicate that APC mutations in CRC are not due to environmental mutagens that randomly damage DNA.

Thermal coagulation-induced changes of the optical properties of normal and adenomatous human colon tissues in vitro in the spectral range 400-1100 nm

International Nuclear Information System (INIS)

Ao Huilan; Xing Da; Wei Huajiang; Gu Huaimin; Wu Guoyong; Lu Jianjun

2008-01-01

The absorption coefficients, the reduced scattering coefficients and the optical penetration depths for native and coagulated human normal and adenomatous colon tissues in vitro were determined over the range of 400-1100 nm using a spectrophotometer with an internal integrating sphere system, and the inverse adding-doubling method was applied to calculate the tissue optical properties from diffuse reflectance and total transmittance measurements. The experimental results showed that in the range of 400-1100 nm there were larger absorption coefficients (P < 0.01) and smaller reduced scattering coefficients (P < 0.01) for adenomatous colon tissues than for normal colon tissues, and there were smaller optical penetration depths for adenomatous colon tissues than for normal colon tissues, especially in the near-infrared wavelength. Thermal coagulation induced significant increase of the absorption coefficients and reduced scattering coefficients for the normal and adenomatous colon tissues, and significantly reduced decrease of the optical penetration depths for the normal and adenomatous colon tissues. The smaller optical penetration depth for coagulated adenomatous colon tissues is a disadvantage for laser-induced thermotherapy (LITT) and photodynamic therapy (PDT). It is necessary to adjust the application parameters of lasers to achieve optimal therapy

Preventing Second Cancers in Colon Cancer Survivors

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In this phase III trial, people who have had curative surgery for colon cancer will be randomly assigned to take sulindac and a placebo, eflornithine and a placebo, both sulindac and eflornithine, or two placebo pills for 36 months.

Gut microbiota facilitates dietary heme-induced epithelial hyperproliferation by opening the mucus barrier in colon

NARCIS (Netherlands)

Ijssennagger, Noortje; Belzer, Clara; Hooiveld, Guido J; Dekker, Jan; van Mil, Saskia W C; Müller, Michael; Kleerebezem, Michiel; van der Meer, Roelof; van Mil, SWC

2015-01-01

Colorectal cancer risk is associated with diets high in red meat. Heme, the pigment of red meat, induces cytotoxicity of colonic contents and elicits epithelial damage and compensatory hyperproliferation, leading to hyperplasia. Here we explore the possible causal role of the gut microbiota in

Xylitol prevents NEFA-induced insulin resistance in rats

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Kishore, P.; Kehlenbrink, S.; Hu, M.; Zhang, K.; Gutierrez-Juarez, R.; Koppaka, S.; El-Maghrabi, M. R.

2013-01-01

Aims/hypothesis Increased NEFA levels, characteristic of type 2 diabetes mellitus, contribute to skeletal muscle insulin resistance. While NEFA-induced insulin resistance was formerly attributed to decreased glycolysis, it is likely that glucose transport is the rate-limiting defect. Recently, the plant-derived sugar alcohol xylitol has been shown to have favourable metabolic effects in various animal models. Furthermore, its derivative xylulose 5-phosphate may prevent NEFA-induced suppression of glycolysis. We therefore examined whether and how xylitol might prevent NEFA-induced insulin resistance. Methods We examined the ability of xylitol to prevent NEFA-induced insulin resistance. Sustained ~1.5-fold elevations in NEFA levels were induced with Intralipid/heparin infusions during 5 h euglycaemic–hyperinsulinaemic clamp studies in 24 conscious non-diabetic Sprague-Dawley rats, with or without infusion of xylitol. Results Intralipid infusion reduced peripheral glucose uptake by ~25%, predominantly through suppression of glycogen synthesis. Co-infusion of xylitol prevented the NEFA-induced decreases in both glucose uptake and glycogen synthesis. Although glycolysis was increased by xylitol infusion alone, there was minimal NEFA-induced suppression of glycolysis, which was not affected by co-infusion of xylitol. Conclusions/interpretation We conclude that xylitol prevented NEFA-induced insulin resistance, with favourable effects on glycogen synthesis accompanying the improved insulin-mediated glucose uptake. This suggests that this pentose sweetener has beneficial insulin-sensitising effects. PMID:22460760

Oral imazalil exposure induces gut microbiota dysbiosis and colonic inflammation in mice.

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Jin, Cuiyuan; Zeng, Zhaoyang; Fu, Zhengwei; Jin, Yuanxiang

2016-10-01

The fungicide imazalil (IMZ) is used extensively in vegetable and fruit plantations and as a post-harvest treatment to avoid rot. Here, we revealed that ingestion of 25, 50 and 100 mg IMZ kg(-1) body weight for 28 d induced gut microbiota dysbiosis and colonic inflammation in mice. The relative abundance of Bacteroidetes, Firmicutes and Actinobacteria in the cecal contents decreased significantly after exposure to 100 mg kg(-1) IMZ for 28 d. In feces, the relative abundance in Bacteroidetes, Firmicutes and Actinobacteria decreased significantly after being exposed to 100 mg kg(-1) IMZ for 1, 14 and 7 d, respectively. High throughput sequencing of the V3-V4 region of the bacterial 16S rRNA gene revealed a significant reduction in the richness and diversity of microbiota in cecal contents and feces of IMZ-treated mice. Operational taxonomic units (OTUs) analysis identified 49.3% of OTUs changed in cecal contents, while 55.6% of OTUs changed in the feces after IMZ exposure. Overall, at the phylum level, the relative abundance of Firmicutes, Proteobacteria and Actinobacteria increased and that of Bacteroidetes decreased in IMZ-treated groups. At the genus level, the abundance of Lactobacillus and Bifidobacterium decreased while those of Deltaproteobacteria and Desulfovibrio increased in response to IMZ exposure. In addition, it was observed that IMZ exposure could induce colonic inflammation characterized by infiltration of inflammatory cells, elevated levels of lipocalin-2 (lcn-2) in the feces, and increased mRNA levels of Tnf-α, IL-1β, IL-22 and IFN-γ in the colon. Our findings strongly suggest that ingestion of IMZ has some risks to human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Apoptosis inducing activity of benzophenanthridine-type alkaloids and 2-arylbenzofuran neolignans in HCT116 colon carcinoma cells.

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

2013-07-15

Thirteen compounds belonging to different classes of alkaloids (1-9) and lignans (10-13), isolated from the methanol extract of roots of the African medicinal plant Zanthoxylum capense, were assayed for their ability as apoptosis inducers in HCT116 colon carcinoma cells. The cytotoxicity of these compounds was evaluated in HCT116 colon carcinoma cells by the MTS assay. Out of the tested compounds, three benzophenanthridine alkaloids (1, 4, and 7), a dibenzyl butyrolactone lignan (10), and two 2-arylbenzofuran neolignans (12 and 13) displayed significant cytotoxicity to HCT116 cells, confirmed by the Guava ViaCount viability assay. The selected compounds (1, 4, 7, 10, 12, and 13) were further tested for apoptosis induction activity in HCT116 cells, by evaluation of nuclear morphology following Hoechst staining, and by caspase-3 like activity assays. Morphologic evaluation of HCT116 nuclei following Hoechst staining and fluorescence microscopy revealed that compounds 1, 4, 7, 10, 12, and 13 induced apoptosis in HCT116 colon carcinoma cells, producing similar, or higher, apoptosis levels when compared with 5-fluorouracil (5-FU), the cornerstone cytotoxic used in colon cancer treatment for several decades. In fact, HCT116 cells developed morphological changes characteristic of apoptosis, including chromatin condensation, nuclear fragmentation and formation of apoptotic bodies. Importantly, compounds 4 and 13 at 20 μM were the most promising in this study, inducing respectively ∼11- and 7-fold increases in apoptotic cells as compared to vehicle control, whereas 5-FU increased apoptosis by ∼2-fold. Apoptosis induction for compounds 4 and 13 was further confirmed by caspase-3-like activity assays, which showed respectively ∼2- and 1.5-fold increases in caspase-3-like activity compared to vehicle control. These results suggested that specific benzophenanthridine alkaloids and 2-arylbenzofuran neolignans isolated from Zanthoxylum capense show strong anticancer

Frondanol, a Nutraceutical Extract from Cucumaria frondosa, Attenuates Colonic Inflammation in a DSS-Induced Colitis Model in Mice

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Sandeep B. Subramanya

2018-04-01

Full Text Available Frondanol is a nutraceutical lipid extract of the intestine of the edible Atlantic sea cucumber, Cucumaria frondosa, with potent anti-inflammatory effects. In the current study, we investigated Frondanol as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J were given 3% dextran sodium sulfate (DSS in drinking water for 7 days to induce colitis. The colitis group received oral Frondanol (100 mg/kg body weight/per day by gavage and were compared with a control group and the DSS group. Disease activity index (DAI and colon histology were scored for macroscopic and microscopic changes. Colonic tissue length, myeloperoxidase (MPO concentration, neutrophil and macrophage marker mRNA, pro-inflammatory cytokine proteins, and their respective mRNAs were measured using ELISA and real-time RT-PCR. The tissue content of leukotriene B4 (LTB4 was also measured using ELISA. Frondanol significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue MPO concentrations, neutrophil and macrophage mRNA expression (F4/80 and MIP-2, and pro-inflammatory cytokine content (IL-1β, IL-6 and TNF-α both at the protein and mRNA level were significantly reduced by Frondanol. The increase in content of the pro-inflammatory mediator leukotriene B4 (LTB4 induced by DSS was also significantly inhibited by Frondanol. It was thus found that Frondanol supplementation attenuates colon inflammation through its potent anti-inflammatory activity.

E. coli-Produced BMP-2 as a Chemopreventive Strategy for Colon Cancer: A Proof-of-Concept Study

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Saravanan Yuvaraj

2012-01-01

Full Text Available Colon cancer is a serious health problem, and novel preventive and therapeutical avenues are urgently called for. Delivery of proteins with anticancer activity through genetically modified bacteria provides an interesting, potentially specific, economic and effective approach here. Interestingly, bone morphogenetic protein 2 (BMP-2 is an important and powerful tumour suppressor in the colon and is thus an attractive candidate protein for delivery through genetically modified bacteria. It has not been shown, however, that BMP production in the bacterial context is effective on colon cancer cells. Here we demonstrate that transforming E. coli with a cDNA encoding an ileal-derived mature human BMP-2 induces effective apoptosis in an in vitro model system for colorectal cancer, whereas the maternal organism was not effective in this respect. Furthermore, these effects were sensitive to cotreatment with the BMP inhibitor Noggin. We propose that prevention and treatment of colorectal cancer using transgenic bacteria is feasible.

Prevention of bacterial colonization of contact lenses with covalently attached selenium and effects on the rabbit cornea.

Science.gov (United States)

Mathews, Steven M; Spallholz, Julian E; Grimson, Mark J; Dubielzig, Richard R; Gray, Tracy; Reid, Ted W

2006-08-01

Although silicone hydrogel materials have produced many corneal health benefits to patients wearing contact lenses, bacteria that cause acute red eye or corneal ulcers are still a concern. A coating that inhibits bacterial colonization while not adversely affecting the cornea should improve the safety of contact lens wear. A covalent selenium (Se) coating on contact lenses was evaluated for safety using rabbits and prevention of bacterial colonization of the contact lenses in vitro. Contact lenses coated with Se were worn on an extended-wear schedule for up to 2 months by 10 New Zealand White rabbits. Corneal health was evaluated with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. Lenses worn by the rabbits were analyzed for protein and lipid deposits. In addition, the ability of Se to block bacterial colonization was tested in vitro by incubating lenses in a Pseudomonas aeruginosa broth followed by scanning electron microscopy of the contact lens surface. The covalent Se coating decreased bacterial colonization in vitro while not adversely affecting the corneal health of rabbits in vivo. The Se coating produced no noticeable negative effects as observed with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. The Se coating did not affect protein or lipid deposition on the contact lenses. The data from this pilot study suggest that a Se coating on contact lenses might reduce acute red eye and bacterial ulceration because of an inhibition of bacterial colonization. In addition, our safety tests suggest that this positive effect can be produced without an adverse effect on corneal health.

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

A key role of microRNA-29b for the suppression of colon cancer cell migration by American ginseng.

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Deepak Poudyal

Full Text Available Metastasis of colon cancer cells increases the risk of colon cancer mortality. We have recently shown that American ginseng prevents colon cancer, and a Hexane extract of American Ginseng (HAG has particularly potent anti-inflammatory and anti-cancer properties. Dysregulated microRNA (miR expression has been observed in several disease conditions including colon cancer. Using global miR expression profiling, we observed increased miR-29b in colon cancer cells following exposure to HAG. Since miR-29b plays a role in regulating the migration of cancer cells, we hypothesized that HAG induces miR-29b expression to target matrix metalloproteinase-2 (MMP-2 thereby suppressing the migration of colon cancer cells. Results are consistent with this hypothesis. Our study supports the understanding that targeting MMP-2 by miR-29b is a mechanism by which HAG suppresses the migration of colon cancer cells.

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

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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.

Vasohibin-1 suppresses colon cancer

OpenAIRE

Liu, Shuai; Han, Bing; Zhang, Qunyuan; Dou, Jie; Wang, Fang; Lin, Wenli; Sun, Yuping; Peng, Guangyong

2015-01-01

Vasohibin-1 (VASH1) is an endogenous angiogenesis inhibitor. However, the clinical relevance of VASH1 in colon cancer and its regulations on cancer angiogenesis and cancer cell biological characteristics are still unknown. Here we showed that stromal VASH1 levels were negatively correlated with tumor size, advanced clinical stage and distant metastases in colon cancer patients. Overexpression of VASH1 in colon cancer cells induced apoptosis and senescence, inhibiting cancer cell growth and co...

Celastrol ameliorates ulcerative colitis-related colorectal cancer in mice via suppressing inflammatory responses and epithelial-mesenchymal transition

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Lianjie eLin

2016-01-01

Full Text Available Celastrol, also named as tripterine, is a pharmacologically active ingredient extracted from the root of traditional Chinese herb Tripterygium wilfordii Hook F with potent anti-inflammatory and anti-tumor activities. In the present study, we investigated the effects of celastrol on ulcerative colitis-related colorectal cancer (UC-CRC as well as colorectal cancer (CRC in vivo and in vitro and explored its underlying mechanisms. UC-CRC model was induced in C57BL/6 mice by administration of azoxymethane (AOM and dextran sodium sulfate (DSS. Colonic tumor xenograft models were developed in BALB/c-nu mice by subcutaneous injection with HCT116 and HT-29 cells. Intragastric administration of celastrol (2 mg/kg/d for 14 weeks significantly increased the survival ratio and reduced the multiplicity of colonic neoplasms compared with AOM/DSS model mice. Mechanically, celastrol treatment significantly prevented AOM/DSS-induced up-regulation of expression levels of oncologic markers including mutated p53 and phospho-p53, β-catenin and proliferating cell nuclear antigen (PCNA. In addition, treatment with celastrol inhibited inflammatory responses, as indicated by the decrease of serum tumor necrosis factor-α (TNF-α, interleukin (IL-1β and IL-6, down-regulation of cyclooxygenase-2 (COX-2 and inducible nitric oxide synthase (iNOS, and inactivation of nuclear factor κB (NF-κB. Moreover, celastrol obviously suppressed epithelial mesenchymal transition (EMT through up-regulating E-cadherin and down-regulating N-cadherin, Vimentin and Snail. Additionally, we also demonstrated that celastrol inhibited human CRC cell proliferation and attenuated colonic xenograft tumor growth via reversing EMT. Taken together, celastrol could effectively ameliorate UC-CRC by suppressing inflammatory responses and EMT, suggesting a potential drug candidate for UC-CRC therapy.

Celastrol Ameliorates Ulcerative Colitis-Related Colorectal Cancer in Mice via Suppressing Inflammatory Responses and Epithelial-Mesenchymal Transition

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Lin, Lianjie; Sun, Yan; Wang, Dongxu; Zheng, Shihang; Zhang, Jing; Zheng, Changqing

2016-01-01

Celastrol, also named as tripterine, is a pharmacologically active ingredient extracted from the root of traditional Chinese herb Tripterygium wilfordii Hook F with potent anti-inflammatory and anti-tumor activities. In the present study, we investigated the effects of celastrol on ulcerative colitis-related colorectal cancer (UC-CRC) as well as CRC in vivo and in vitro and explored its underlying mechanisms. UC-CRC model was induced in C57BL/6 mice by administration of azoxymethane (AOM) and dextran sodium sulfate (DSS). Colonic tumor xenograft models were developed in BALB/c-nu mice by subcutaneous injection with HCT116 and HT-29 cells. Intragastric administration of celastrol (2 mg/kg/d) for 14 weeks significantly increased the survival ratio and reduced the multiplicity of colonic neoplasms compared with AOM/DSS model mice. Mechanically, celastrol treatment significantly prevented AOM/DSS-induced up-regulation of expression levels of oncologic markers including mutated p53 and phospho-p53, β-catenin and proliferating cell nuclear antigen (PCNA). In addition, treatment with celastrol inhibited inflammatory responses, as indicated by the decrease of serum tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6, down-regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), and inactivation of nuclear factor κB (NF-κB). Moreover, celastrol obviously suppressed epithelial-mesenchymal transition (EMT) through up-regulating E-cadherin and down-regulating N-cadherin, Vimentin and Snail. Additionally, we also demonstrated that celastrol inhibited human CRC cell proliferation and attenuated colonic xenograft tumor growth via reversing EMT. Taken together, celastrol could effectively ameliorate UC-CRC by suppressing inflammatory responses and EMT, suggesting a potential drug candidate for UC-CRC therapy. PMID:26793111

Prophylactic Saccharomyces boulardii versus nystatin for the prevention of fungal colonization and invasive fungal infection in premature infants.

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Demirel, Gamze; Celik, Istemi Han; Erdeve, Omer; Saygan, Sibel; Dilmen, Ugur; Canpolat, Fuat Emre

2013-10-01

This study aims to compare the efficacy of orally administered Saccharomyces boulardii versus nystatin in prevention of fungal colonization and invasive fungal infections in very low birth weight infants. A prospective, randomized comparative study was conducted in preterm infants with a gestational age of ≤ 32 weeks and birth weight of ≤ 1,500 g. They were randomized into two groups, to receive S. boulardii or nystatin. Skin and stool cultures were performed for colonization and blood cultures for invasive infections, weekly. A total of 181 infants were enrolled (S. boulardii group, n = 91; nystatin group, n = 90). Fungal colonization of the skin (15.4 vs 18.9 %, p = 0.532) and the stool (32.2 vs 27 %, p = 0.441) were not different between the probiotic and nystatin groups. Two patients had Candida-positive blood culture in the nystatin group whereas none in the probiotic group. Feeding intolerance, clinical sepsis, and number of sepsis attacks were significantly lower in the probiotics group than in the nystatin group. Prophylactic S. boulardii supplementation is as effective as nystatin in reducing fungal colonization and invasive fungal infection, more effective in reducing the incidence of clinical sepsis and number of sepsis attacks and has favorable effect on feeding intolerance.

DNA repair by MGMT, but not AAG, causes a threshold in alkylation-induced colorectal carcinogenesis.

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Fahrer, Jörg; Frisch, Janina; Nagel, Georg; Kraus, Alexander; Dörsam, Bastian; Thomas, Adam D; Reißig, Sonja; Waisman, Ari; Kaina, Bernd

2015-10-01

Epidemiological studies indicate that N-nitroso compounds (NOC) are causally linked to colorectal cancer (CRC). NOC induce DNA alkylations, including O (6)-methylguanine (O (6)-MeG) and N-methylated purines, which are repaired by O (6)-MeG-DNA methyltransferase (MGMT) and N-alkyladenine-DNA glycosylase (AAG)-initiated base excision repair, respectively. In view of recent evidence of nonlinear mutagenicity for NOC-like compounds, the question arises as to the existence of threshold doses in CRC formation. Here, we set out to determine the impact of DNA repair on the dose-response of alkylation-induced CRC. DNA repair proficient (WT) and deficient (Mgmt (-/-), Aag (-/-) and Mgmt (-/-)/Aag (-/-)) mice were treated with azoxymethane (AOM) and dextran sodium sulfate to trigger CRC. Tumors were quantified by non-invasive mini-endoscopy. A non-linear increase in CRC formation was observed in WT and Aag (-/-) mice. In contrast, a linear dose-dependent increase in tumor frequency was found in Mgmt (-/-) and Mgmt (-/-)/Aag (-/-) mice. The data were corroborated by hockey stick modeling, yielding similar carcinogenic thresholds for WT and Aag (-/-) and no threshold for MGMT lacking mice. O (6)-MeG levels and depletion of MGMT correlated well with the observed dose-response in CRC formation. AOM induced dose-dependently DNA double-strand breaks in colon crypts including Lgr5-positive colon stem cells, which coincided with ATR-Chk1-p53 signaling. Intriguingly, Mgmt (-/-) mice displayed significantly enhanced levels of γ-H2AX, suggesting the usefulness of γ-H2AX as an early genotoxicity marker in the colorectum. This study demonstrates for the first time a non-linear dose-response for alkylation-induced colorectal carcinogenesis and reveals DNA repair by MGMT, but not AAG, as a key node in determining a carcinogenic threshold. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ursodeoxycholic acid in patients with ulcerative colitis and primary sclerosing cholangitis for prevention of colon cancer: a meta-analysis.

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Ashraf, Imran; Choudhary, Abhishek; Arif, Murtaza; Matteson, Michelle L; Hammad, Hazem T; Puli, Srinivas R; Bechtold, Matthew L

2012-04-01

Colon cancer risk is high in patients with ulcerative colitis (UC) and primary sclerosing cholangitis (PSC). Ursodeoxycholic acid has been shown to have some promise as a chemopreventive agent. A meta-analysis was performed to compare the efficacy of ursodeoxycholic acid in the prevention of colonic neoplasia in patients with UC and PSC. Multiple databases were searched (January 2011). Studies examining the use of ursodeoxycholic acid vs. no ursodeoxycholic acid or placebo in adult patients with UC and PSC were included. Data were extracted in standard forms by two independent reviewers. Meta-analysis for the effect of ursodeoxycholic acid was performed by calculating pooled estimates of adenoma or colon cancer formation by odds ratio (OR) with random effects model. Heterogeneity was assessed by calculating the I (2) measure of inconsistency. RevMan 5 was utilized for statistical analysis. Four studies (n = 281) met the inclusion criteria. The studies were of adequate quality. Ursodeoxycholic acid demonstrated no overall improvement in adenoma (OR 0.53; 95 % CI: 0.19-1.48, p = 0.23) or colon cancer occurrence (OR 0.50; 95 % CI: 0.18-1.43, p = 0.20) as compared to no ursodeoxycholic acid or placebo in patients with UC and PSC. Ursodeoxycholic acid use in patients with UC and PSC does not appear to decrease the risk of adenomas or colon cancer.

The protective effect of fermented milk kefir on radiation-induced apoptosis in colonic crypt cells of rats

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Matsuu, Mutsumi; Shichijo, Kazuko; Okaichi, Kumio

2003-01-01

To evaluate the effect of fermented milk kefir on X-ray-induced apoptosis in the colon of rats, we examined the apoptotic index, the mean number of apoptotic cells detected by H and E staining per crypt in the colon, in control rats and kefir-pretreated rats drinking kefir for 12 days before irradiation. Apoptotic cells were confirmed by TUNEL staining, and active caspase-3 expression was studied by immunohistochemistry. The cell position of apoptotic cells and active caspase-3 positive cells were examined. The apoptotic index of kefir-treated rats was significantly (p<0.05) decreased 2 h after 1 Gy irradiation in comparison with control rats at crypt cell positions 1-3, 5-7, 13, and 15. Active caspase-3 expression in the kefir-treated rats was also significantly (p<0.05) reduced in comparison with control rats 2 h after 1 Gy irradiation at crypt cell positions 1-4, 13, and 15. This study indicated that kefir protects colonic crypt cells against radiation-induced apoptosis, which was most pronounced in the stem cell region of the crypt. The antiapoptotic effect of fermented milk kefir was due to the inhibition of caspase-3 activation. (author)

Urotensin-II receptor is over-expressed in colon cancer cell lines and in colon carcinoma in humans.

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Federico, Alessandro; Zappavigna, Silvia; Romano, Marco; Grieco, Paolo; Luce, Amalia; Marra, Monica; Gravina, Antonietta Gerarda; Stiuso, Paola; D'Armiento, Francesco Paolo; Vitale, Giovanni; Tuccillo, Concetta; Novellino, Ettore; Loguercio, Carmela; Caraglia, Michele

2014-01-01

Urotensin (U)-II receptor (UTR) has been previously reported to be over-expressed in a number of tumours. Whether UTR-related pathway plays a role in colon carcinogenesis is unknown. We evaluated UTR protein and mRNA expression in human epithelial colon cancer cell lines and in normal colon tissue, adenomatous polyps and colon cancer. U-II protein expression was assessed in cancer cell lines. Moreover, we evaluated the effects of U-II(4-11) (an UTR agonist), antagonists and knockdown of UTR protein expression through a specific shRNA, on proliferation, invasion and motility of human colon cancer cells. Cancer cell lines expressed U-II protein and UTR protein and mRNA. By immunohistochemistry, UTR was expressed in 5-30% of epithelial cells in 45 normal controls, in 30-48% in 21 adenomatous polyps and in 65-90% in 48 colon adenocarcinomas. UTR mRNA expression was increased by threefold in adenomatous polyps and eightfold in colon cancer, compared with normal colon. U-II(4-11) induced a 20-40% increase in cell growth while the blockade of the receptor with specific antagonists caused growth inhibition of 20-40%. Moreover, the knock down of UTR with a shRNA or the inhibition of UTR with the antagonist urantide induced an approximately 50% inhibition of both motility and invasion. UTR appears to be involved in the regulation of colon cancer cell invasion and motility. These data suggest that UTR-related pathway may play a role in colon carcinogenesis and that UTR may function as a target for therapeutic intervention in colon cancer. © 2013 Stichting European Society for Clinical Investigation Journal Foundation.

The inflammatory mediator leukotriene D{sub 4} induces subcellular β-catenin translocation and migration of colon cancer cells

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Salim, Tavga [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden); Sand-Dejmek, Janna [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden); Section of Surgery, Department of Clinical Sciences, Lund University, Skåne University Hospital, Malmö (Sweden); Bayer HealthCare, Pharmaceuticals Medical Affairs, Solna (Sweden); Sjölander, Anita, E-mail: anita.sjolander@med.lu.se [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden)

2014-02-15

The abnormal activation of the Wnt/β-catenin pathway frequently occurs in colorectal cancer. The nuclear translocation of β-catenin activates the transcription of target genes that promote cell proliferation, survival, and invasion. The pro-inflammatory mediator leukotriene D{sub 4} (LTD{sub 4}) exerts its effects through the CysLT{sub 1} receptor. We previously reported an upregulation of CysLT{sub 1}R in patients with colon cancer, suggesting the importance of leukotrienes in colon cancer. The aim of this study was to investigate the impact of LTD{sub 4} on Wnt/β-catenin signaling and its effects on proliferation and migration of colon cancer cells. LTD{sub 4} stimulation led to an increase in β-catenin expression, β-catenin nuclear translocation and the subsequent transcription of MYC and CCND1. Furthermore, LTD{sub 4} significantly reduced the expression of E-cadherin and β-catenin at the plasma membrane and increased the migration and proliferation of HCT116 colon cancer cells. The effects of LTD{sub 4} can be blocked by the inhibition of CysLT{sub 1}R. Furthermore, LTD{sub 4} induced the inhibition of glycogen synthase kinase 3 (GSK)-3β activity, indicating a crosstalk between the G-protein-coupled receptor CysLT{sub 1} and the Wnt/β-catenin pathway. In conclusion, LTD{sub 4}, which can be secreted from macrophages and leukocytes in the tumor microenvironment, induces β-catenin translocation and the activation of β-catenin target genes, resulting in the increased proliferation and migration of colon cancer cells. - Highlights: • Leukotriene D{sub 4} (LTD{sub 4}) lowers membrane β-catenin but increases nuclear β-catenin levels in colon cancer cells. • In agreement, LTD{sub 4} triggers inactivation of GSK-3β, activation of TCF/LEF and increased expression of Cyclin D1 and c-Myc. • LTD{sub 4} also caused a significant reduction in the expression of E-cadherin and an increased migration of colon cancer cells.

Inositol Hexaphosphate Inhibits Proliferation and Induces Apoptosis of Colon Cancer Cells by Suppressing the AKT/mTOR Signaling Pathway

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Małgorzata Kapral

2017-10-01

Full Text Available Abstract: AKT, a serine/threonine protein kinase and mammalian target of rapamycin (mTOR plays a critical role in the proliferation and resistance to apoptosis that are essential to the development and progression of colon cancer. Therefore, AKT/mTOR signaling pathway has been recognized as an attractive target for anticancer therapy. Inositol hexaphosphate (InsP6, a natural occurring phytochemical, has been shown to have both preventive and therapeutic effects against various cancers, however, its exact molecular mechanisms of action are not fully understood. The aim of the in vitro study was to investigate the anticancer activity of InsP6 on colon cancer with the focus on inhibiting the AKT1 kinase and p70S6K1 as mTOR effector, in relation to proliferation and apoptosis of cells. The colon cancer Caco-2 cells were cultured using standard techniques and exposed to InsP6 at different concentrations (1 mM, 2.5 mM and 5 mM. Cellular proliferative activity was monitored by 5-bromo-2′-deoxyuridine (BrdU incorporation into cellular DNA. Flow cytometric analysis was performed for cell cycle progression and apoptosis studies. Real-time RT-qPCR was used to validate mRNA levels of CDNK1A, CDNK1B, CASP3, CASP9, AKT1 and S6K1 genes. The concentration of p21 protein as well as the activities of caspase 3, AKT1 and p70S6K1 were determined by the ELISA method. The results revealed that IP6 inhibited proliferation and stimulated apoptosis of colon cancer cells. This effect was mediated by an increase in the expression of genes encoding p21, p27, caspase 3, caspase 9 as well a decrease in transcription of AKT1 and S6K1. InsP6 suppressed phosphorylation of AKT1 and p70S6K1, downstream effector of mTOR. Based on these studies it may be concluded that InsP6 can reduce proliferation and induce apoptosis through inhibition of the AKT/mTOR pathway and mTOR effector followed by modulation of the expression and activity of several key components of these pathways in

Emergency management of acute colonic cancer obstruction.

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Gainant, A

2012-02-01

Emergency management of obstructing colonic cancer depends on both tumor location and stage, general condition of the patient and surgeon's experience. Right sided or transverse colon obstructing cancers are usually treated by right hemicolectomy-extended if necessary to the transverse colon-with primary anastomosis. For left-sided obstructing cancer, in patients with low surgical risk, primary resection and anastomosis associated with on-table irrigation or manual decompression can be performed. It prevents the confection of a loop colostomy but presents the risk of anastomotic leakage. Subtotal or total colectomy allows the surgeon to encompass distended and fecal-loaded colon, and to perform one-stage resection and anastomosis. Its disadvantage is an increased daily frequency of stools. It must be performed only in cases of diastatic colon perforation or synchronous right colonic cancer. In patients with high surgical risk, Hartmann procedure must be preferred. It allows the treatment of both obstruction and cancer, and prevents anastomotic leakage but needs a second operation to reverse the colostomy. Colonic stenting is clinically successful in up to 90% in specialized groups. It is used as palliation in patients with disseminated disease or bridge to surgery in the others. If stent insertion is not possible, loop colostomy is still indicated in patients at high surgical risk. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Horizontal transmission of Candida albicans and evidence of a vaccine response in mice colonized with the fungus.

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Cutler, Jim E; Corti, Miriam; Lambert, Patrick; Ferris, Michael; Xin, Hong

2011-01-01

Disseminated candidiasis is the third leading nosocomial blood stream infection in the United States and is often fatal. We previously showed that disseminated candidiasis was preventable in normal mice by immunization with either a glycopeptide or a peptide synthetic vaccine, both of which were Candida albicans cell wall derived. A weakness of these studies is that, unlike humans, mice do not have a C. albicans GI flora and they lack Candida serum antibodies. We examined the influence of C. albicans GI tract colonization and serum antibodies on mouse vaccination responses to the peptide, Fba, derived from fructose bisphosphate aldolase which has cytosolic and cell wall distributions in the fungus. We evaluated the effect of live C. albicans in drinking water and antimicrobial agents on establishment of Candida colonization of the mouse GI tract. Body mass, C. albicans in feces, and fungal-specific serum antibodies were monitored longitudinally. Unexpectedly, C. albicans colonization occurred in mice that received only antibiotics in their drinking water, provided that the mice were housed in the same room as intentionally colonized mice. The fungal strain in unintentionally colonized mice appeared identical to the strain used for intentional GI-tract colonization. This is the first report of horizontal transmission and spontaneous C. albicans colonization in mice. Importantly, many Candida-colonized mice developed serum fungal-specific antibodies. Despite the GI-tract colonization and presence of serum antibodies, the animals made antibodies in response to the Fba immunogen. This mouse model has potential for elucidating C. albicans horizontal transmission and for exploring factors that induce host defense against disseminated candidiasis. Furthermore, a combined protracted GI-tract colonization with Candida and the possibility of serum antibody responses to the presence of the fungus makes this an attractive mouse model for testing the efficacy of vaccines

Horizontal transmission of Candida albicans and evidence of a vaccine response in mice colonized with the fungus.

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Jim E Cutler

Full Text Available Disseminated candidiasis is the third leading nosocomial blood stream infection in the United States and is often fatal. We previously showed that disseminated candidiasis was preventable in normal mice by immunization with either a glycopeptide or a peptide synthetic vaccine, both of which were Candida albicans cell wall derived. A weakness of these studies is that, unlike humans, mice do not have a C. albicans GI flora and they lack Candida serum antibodies. We examined the influence of C. albicans GI tract colonization and serum antibodies on mouse vaccination responses to the peptide, Fba, derived from fructose bisphosphate aldolase which has cytosolic and cell wall distributions in the fungus. We evaluated the effect of live C. albicans in drinking water and antimicrobial agents on establishment of Candida colonization of the mouse GI tract. Body mass, C. albicans in feces, and fungal-specific serum antibodies were monitored longitudinally. Unexpectedly, C. albicans colonization occurred in mice that received only antibiotics in their drinking water, provided that the mice were housed in the same room as intentionally colonized mice. The fungal strain in unintentionally colonized mice appeared identical to the strain used for intentional GI-tract colonization. This is the first report of horizontal transmission and spontaneous C. albicans colonization in mice. Importantly, many Candida-colonized mice developed serum fungal-specific antibodies. Despite the GI-tract colonization and presence of serum antibodies, the animals made antibodies in response to the Fba immunogen. This mouse model has potential for elucidating C. albicans horizontal transmission and for exploring factors that induce host defense against disseminated candidiasis. Furthermore, a combined protracted GI-tract colonization with Candida and the possibility of serum antibody responses to the presence of the fungus makes this an attractive mouse model for testing the

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.

Pharmacological identification of β-adrenoceptor subtypes mediating isoprenaline-induced relaxation of guinea pig colonic longitudinal smooth muscle.

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Chino, Daisuke; Sone, Tomoyo; Yamazaki, Kumi; Tsuruoka, Yuri; Yamagishi, Risa; Shiina, Shunsuke; Obara, Keisuke; Yamaki, Fumiko; Higai, Koji; Tanaka, Yoshio

2018-01-01

Object We aimed to identify the β-adrenoceptor (β-AR) subtypes involved in isoprenaline-induced relaxation of guinea pig colonic longitudinal smooth muscle using pharmacological and biochemical approaches. Methods Longitudinal smooth muscle was prepared from the male guinea pig ascending colon and contracted with histamine prior to comparing the relaxant responses to three catecholamines (isoprenaline, adrenaline, and noradrenaline). The inhibitory effects of subtype-selective β-AR antagonists on isoprenaline-induced relaxation were then investigated. Results The relaxant potencies of the catecholamines were ranked as: isoprenaline > noradrenaline ≈ adrenaline, whereas the rank order was isoprenaline > noradrenaline > adrenaline in the presence of propranolol (a non-selective β-AR antagonist; 3 × 10 -7 M). Atenolol (a selective β 1 -AR antagonist; 3 × 10 -7 -10 -6  M) acted as a competitive antagonist of isoprenaline-induced relaxation, and the pA 2 value was calculated to be 6.49 (95% confidence interval: 6.34-6.83). The relaxation to isoprenaline was not affected by ICI-118,551 (a selective β 2 -AR antagonist) at 10 -9 -10 -8  M, but was competitively antagonized by 10 -7 -3 × 10 -7  M, with a pA 2 value of 7.41 (95% confidence interval: 7.18-8.02). In the presence of propranolol (3 × 10 -7 M), the relaxant effect of isoprenaline was competitively antagonized by bupranolol (a non-selective β-AR antagonist), with a pA 2 value of 5.90 (95% confidence interval: 5.73-6.35). Conclusion These findings indicated that the β-AR subtypes involved in isoprenaline-induced relaxation of colonic longitudinal guinea pig muscles are β 1 -AR and β 3 -AR.

Colon cancer chemoprevention with ginseng and other botanicals.

OpenAIRE

Wargovich, M J

2001-01-01

Colorectal cancer is becoming increasingly common in Asian countries and still remains the second leading cause of cancer deaths in the United States. Efforts to prevent colon cancer have targeted early detection through screening and chemoprevention. For the last ten years our laboratory has utilized an in vivo screening assay for the testing of potential cancer preventives for colon cancer. We have conducted investigations on over 150 compounds including many with botanical or herbal origin...

Absence of p53 gene mutations in mice colon pre-cancerous stage induced by o-nitrotoluene

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Nahed A Hussien

2014-01-01

Conclusion: The results from the present study indicate that point mutations in the p53 gene, in the coding region (exons 5-8 and outside it (exons 10, 11, are not involved in the development of the colon precancerous stage induced by o-nt in mice.

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.

Cell proliferation in dimethylhydrazine-induced colonic adenocarcinomata following cytotoxic drug treatment.

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Tutton, P J; Barkla, D H

1978-08-25

A stathmokinetic technique was used to study cell proliferation in dimethylhydrazine-induced adenocarcinomata of rat colon following treatment with cytotoxic drugs. The rate of cell division was significantly increased three days after treatment with 5,7-dihydroxytryptamine and seven days after treatment with 5-fluorouracil. Acceleration of tumour cell proliferation following 5,7-dihydroxytryptamine treatment was inhibited by treating animals with the antiseritoninergic drug Xylamidine Tosylate. Acceleration of tumour cell proliferation following 5-fluorouracil treatment was inhibited by treating animals either with the antiseritoninergic drug BW501 or with the histamine H2-receptor blocking drug Cimetidine.

Sphingosine Kinase 2 and Ceramide Transport as Key Targets of the Natural Flavonoid Luteolin to Induce Apoptosis in Colon Cancer Cells.

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Loubna Abdel Hadi

Full Text Available The plant flavonoid luteolin exhibits different biological effects, including anticancer properties. Little is known on the molecular mechanisms underlying its actions in colorectal cancer (CRC. Here we investigated the effects of luteolin on colon cancer cells, focusing on the balance between ceramide and sphingosine-1-phosphate (S1P, two sphingoid mediators with opposite roles on cell fate. Using cultured cells, we found that physiological concentrations of luteolin induce the elevation of ceramide, followed by apoptotic death of colon cancer cells, but not of differentiated enterocytes. Pulse studies revealed that luteolin inhibits ceramide anabolism to complex sphingolipids. Further experiments led us to demonstrate that luteolin induces an alteration of the endoplasmic reticulum (ER-Golgi flow of ceramide, pivotal to its metabolic processing to complex sphingolipids. We report that luteolin exerts its action by inhibiting both Akt activation, and sphingosine kinase (SphK 2, with the consequent reduction of S1P, an Akt stimulator. S1P administration protected colon cancer cells from luteolin-induced apoptosis, most likely by an intracellular, receptor-independent mechanism. Overall this study reveals for the first time that the dietary flavonoid luteolin exerts toxic effects on colon cancer cells by inhibiting both S1P biosynthesis and ceramide traffic, suggesting its dietary introduction/supplementation as a potential strategy to improve existing treatments in CRC.

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.

Apoptotic effects of inositol hexaphosphate on biomarker Itpr3 in induced colon rat carcinogenesis Efeito de apoptose do inositol hexafosfato no marcador biológico Itpr3 em carcinogênese induzida de colo em ratos

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Marks Guido

2008-04-01

Full Text Available PURPOSE: To study the effect of the modulation of inositol hexaphosphate (IP6 in the biological immunohistochemistry expression of cellular signaling marker apoptosis, in model of carcinogenesis of colon induced by azoxymethane (AOM. METHODS: Wistar rats (N=112 distributed in 4 groups (n=28: Control; B, AOM (5 mg kg-1, 2x, to break week 3; C, IP6 (in water 1%, six weeks; D, IP6+AOM. Weekly euthanasia (n=7, from week three. Immunohistochemistry of ascendant colon with biological marker inositol 1,4,5 triphosphate receptor type III (Itpr3. Quantification of the immune-expression with use of computer-assisted image processing. Analysis statistics of the means between groups, weeks in groups, groups in weeks, and established significance when pOBJETIVO: Estudar os efeitos da modulação do inositol hexafosfato (IP6 na expressão imunoistoquímica de marcador biológico de sinalização celular de apoptose, em modelo de carcinogênese induzida pelo azoximetano (AOM. MÉTODOS: Ratos Wistar (N=112 distribuídos em 4 grupos (n=28: A, controle; B, AOM (5 mg Kg-1, 2x, a partir semana 3; C, IP6 (em água a 1%, seis semanas; D, IP6+AOM. Eutanásia semanal (n=7, a partir de semana três. Imunoistoquímica de colo ascendente com marcador biológico inositol 1,4,5 trisphosphate receptor type III (Itpr3. Quantificação da imunoexpressão com uso de processamento imagem assistida computador. Análise estatística da expressão média entre grupos, semanas em grupos e grupos em semanas, e estabelecido significância quando p<0.05. RESULTADOS: Evidenciou-se diferença significante entre grupos na expressão de Itpr3, p<0.0001; com diminuição Itpr3 de grupo BxD, p<0.001. CONCLUSÃO: O inositol hexafostato promove a modulação de marcador biológico com diminuição Itpr3 em carcinogênese de colo.

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

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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.

Death Receptor-Induced Apoptosis Signalling Regulation by Ezrin Is Cell Type Dependent and Occurs in a DISC-Independent Manner in Colon Cancer Cells

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Iessi, Elisabetta; Zischler, Luciana; Etringer, Aurélie; Bergeret, Marion; Morlé, Aymeric; Jacquemin, Guillaume; Morizot, Alexandre; Shirley, Sarah; Lalaoui, Najoua; Elifio-Esposito, Selene L.; Fais, Stefano; Garrido, Carmen; Solary, Eric; Micheau, Olivier

2015-01-01

Ezrin belongs to the ERM (ezrin-radixin-moesin) protein family and has been demonstrated to regulate early steps of Fas receptor signalling in lymphoid cells, but its contribution to TRAIL-induced cell death regulation in adherent cancer cells remains unknown. In this study we report that regulation of FasL and TRAIL-induced cell death by ezrin is cell type dependant. Ezrin is a positive regulator of apoptosis in T-lymphoma cell line Jurkat, but a negative regulator in colon cancer cells. Using ezrin phosphorylation or actin-binding mutants, we provide evidence that negative regulation of death receptor-induced apoptosis by ezrin occurs in a cytoskeleton- and DISC-independent manner, in colon cancer cells. Remarkably, inhibition of apoptosis induced by these ligands was found to be tightly associated with regulation of ezrin phosphorylation on serine 66, the tumor suppressor gene WWOX and activation of PKA. Deficiency in WWOX expression in the liver cancer SK-HEP1 or the pancreatic Mia PaCa-2 cell lines as well as WWOX silencing or modulation of PKA activation by pharmacological regulators, in the colon cancer cell line SW480, abrogated regulation of TRAIL signalling by ezrin. Altogether our results show that death receptor pro-apoptotic signalling regulation by ezrin can occur downstream of the DISC in colon cancer cells. PMID:26010871

Death Receptor-Induced Apoptosis Signalling Regulation by Ezrin Is Cell Type Dependent and Occurs in a DISC-Independent Manner in Colon Cancer Cells.

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Elisabetta Iessi

Full Text Available Ezrin belongs to the ERM (ezrin-radixin-moesin protein family and has been demonstrated to regulate early steps of Fas receptor signalling in lymphoid cells, but its contribution to TRAIL-induced cell death regulation in adherent cancer cells remains unknown. In this study we report that regulation of FasL and TRAIL-induced cell death by ezrin is cell type dependant. Ezrin is a positive regulator of apoptosis in T-lymphoma cell line Jurkat, but a negative regulator in colon cancer cells. Using ezrin phosphorylation or actin-binding mutants, we provide evidence that negative regulation of death receptor-induced apoptosis by ezrin occurs in a cytoskeleton- and DISC-independent manner, in colon cancer cells. Remarkably, inhibition of apoptosis induced by these ligands was found to be tightly associated with regulation of ezrin phosphorylation on serine 66, the tumor suppressor gene WWOX and activation of PKA. Deficiency in WWOX expression in the liver cancer SK-HEP1 or the pancreatic Mia PaCa-2 cell lines as well as WWOX silencing or modulation of PKA activation by pharmacological regulators, in the colon cancer cell line SW480, abrogated regulation of TRAIL signalling by ezrin. Altogether our results show that death receptor pro-apoptotic signalling regulation by ezrin can occur downstream of the DISC in colon cancer cells.

Colonic insufflation with carbon monoxide gas inhibits the development of intestinal inflammation in rats

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Takagi Tomohisa

2012-09-01

Full Text Available Abstract Background The pathogenesis of inflammatory bowel disease (IBD is complex, and an effective therapeutic strategy has yet to be established. Recently, carbon monoxide (CO has been reported to be capable of reducing inflammation by multiple mechanisms. In this study, we evaluated the role of colonic CO insufflation in acute colitis induced by trinitrobenzene sulfonic acid (TNBS in rats. Methods Acute colitis was induced with TNBS in male Wistar rats. Following TNBS administration, the animals were treated daily with 200 ppm of intrarectal CO gas. The distal colon was removed to evaluate various parameters of inflammation, including thiobarbituric acid (TBA-reactive substances, tissue-associated myeloperoxidase (MPO activity, and the expression of cytokine-induced neutrophil chemoattractant (CINC-1 in colonic mucosa 7 days after TNBS administration. Results The administration of TNBS induced ulceration with surrounding edematous swelling in the colon. In rats treated with CO gas, the colonic ulcer area was smaller than that of air-treated rats 7 days after TNBS administration. The wet colon weight was significantly increased in the TNBS-induced colitis group, which was markedly abrogated by colonic insufflation with CO gas. The increase of MPO activity, TBA-reactive substances, and CINC-1 expression in colonic mucosa were also significantly inhibited by colonic insufflation with CO gas. Conclusions Colonic insufflation with CO gas significantly ameliorated TNBS-induced colitis in rats. Clinical application of CO gas to improve colonic inflammatory conditions such as IBD might be useful.

N-acetylcysteine prevents the development of gastritis induced by Helicobacter pylori infection.

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Jang, Sungil; Bak, Eun-Jung; Cha, Jeong-Heon

2017-05-01

Helicobacter pylori (H. pylori) is a human gastric pathogen, causing various gastric diseases ranging from gastritis to gastric adenocarcinoma. It has been reported that combining N-acetylcysteine (NAC) with conventional antibiotic therapy increases the success rate of H. pylori eradication. We evaluated the effect of NAC itself on the growth and colonization of H. pylori, and development of gastritis, using in vitro liquid culture system and in vivo animal models. H. pylori growth was evaluated in broth culture containing NAC. The H. pylori load and histopathological scores of stomachs were measured in Mongolian gerbils infected with H. pylori strain 7.13, and fed with NAC-containing diet. In liquid culture, NAC inhibited H. pylori growth in a concentration-dependent manner. In the animal model, 3-day administration of NAC after 1 week from infection reduced the H. pylori load; 6-week administration of NAC after 1 week from infection prevented the development of gastritis and reduced H. pylori colonization. However, no reduction in the bacterial load or degree of gastritis was observed with a 6-week administration of NAC following 6-week infection period. Our results indicate that NAC may exert a beneficial effect on reduction of bacterial colonization, and prevents the development of severe inflammation, in people with initial asymptomatic or mild H. pylori infection.

Effect of probiotics on the development of dimethylhydrazine-induced preneoplastic lesions in the mice colon

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Juliana Costa Liboredo

2013-05-01

Full Text Available PURPOSE: To determine the effect of probiotics on the development of chemically induced (1, 2-dimethylhydrazine colonic preneoplastic lesions, in mice. METHODS: The animals were divided into five groups. The control group was injected with carcinogen alone and the other groups also received probiotics (1- Lactobacillus delbrueckii UFV-H2b20; 2- Bifidobacterium animalis var. lactis Bb12; 3- L. delbrueckii UFV-H2b20 plus B. animalis var. lactis Bb12; and 4- Saccharomyces boulardii administered orally in drinking water throughout fourteen weeks. RESULTS: Consumption of lactobacilli and bifidobacteria alone resulted in a significant reduction of the total number of aberrant crypt foci (55.7% and 45.1%, respectively. Significant reduction in the number of these small foci (3 aberrant crypts crypts had no significant reduction. CONCLUSION: L. delbrueckii UFV-H2b20 and B. animalis var. lactis Bb12 administered alone protect colonic preneoplastic lesions in mice, while the combined treatment of these bacteria and the administration of S.boulardii were not effective in reducing such colonic lesions.

Interleukin 21 controls tumour growth and tumour immunosurveillance in colitis-associated tumorigenesis in mice.

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Jauch, Dominik; Martin, Maria; Schiechl, Gabriela; Kesselring, Rebecca; Schlitt, Hans Jürgen; Geissler, Edward K; Fichtner-Feigl, Stefan

2011-12-01

Colitis-associated tumorigenesis is a balance between proliferation of tumour cells and tumour immunosurveillance. The role of T-helper-cell-derived cytokines in tumour growth is not fully understood. In this study the authors investigated the influence of interleukin (IL) 21 on intestinal tumorigenesis. Chronic colitis was induced in IL-21(-/-) and littermate control wild-type mice with three cycles of 1.5% dextran sulphate sodium (DSS) over 7 days followed by 7 days of drinking water. Mice received an azoxymethane injection on day 0 of DSS-colitis to induce tumorigenesis. Immunohistochemistry was performed on inflamed and tumour-bearing areas of colons. Cytokine expression of isolated colonic CD4 T cells was determined by ELISA. Cytotoxic capacity of isolated colonic CD8 T cells targeting tumour cells was evaluated by flow cytometry and quantitative cytotoxicity assay. Apoptosis of tumour cells was determined by TUNEL assay of colonic sections. Increasing expression of IL-21 was observed in chronic colitis, which showed functional importance, since IL-21 deficiency prevented chronic DSS-colitis development. Further, in the absence of IL-21, significantly fewer tumour nodules were detected, despite a similar extent of intestinal inflammation. In wild-type mice, 8.6±1.9 tumour nodules were found compared with 1.0±1.2 in IL-21-deficient mice. In tumour-bearing IL-21-deficient mice, intestinal inflammation was restored and partly dependent on interferon (IFN)-γ, whereas the inflammation in wild-type mice showed high IL-17A concentrations. In these rare tumours in IL-21-deficient mice, tumour cell proliferation (Ki-67) was decreased, while cell apoptosis was increased, compared with wild-type mice. Increased IFNγ expression in tumour-bearing IL-21-deficient mice led to increased tumour immunosurveillance mediated by cytotoxic CD8CD103 T cells targeting E-cadherin(+) colonic tumour cells and therefore limited tumour growth. These results indicate that IL-21

Ursodeoxycholic acid and lithocholic acid exert anti-inflammatory actions in the colon.

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Ward, Joseph B J; Lajczak, Natalia K; Kelly, Orlaith B; O'Dwyer, Aoife M; Giddam, Ashwini K; Ní Gabhann, Joan; Franco, Placido; Tambuwala, Murtaza M; Jefferies, Caroline A; Keely, Simon; Roda, Aldo; Keely, Stephen J

2017-06-01

Ward JB, Lajczak NK, Kelly OB, O'Dwyer AM, Giddam AK, Ní Gabhann J, Franco P, Tambuwala MM, Jefferies CA, Keely S, Roda A, Keely SJ. Ursodeoxycholic acid and lithocholic acid exert anti-inflammatory actions in the colon. Am J Physiol Gastrointest Liver Physiol 312: G550-G558, 2017. First published March 30, 2017; doi:10.1152/ajpgi.00256.2016.-Inflammatory bowel diseases (IBD) comprise a group of common and debilitating chronic intestinal disorders for which currently available therapies are often unsatisfactory. The naturally occurring secondary bile acid, ursodeoxycholic acid (UDCA), has well-established anti-inflammatory and cytoprotective actions and may therefore be effective in treating IBD. We aimed to investigate regulation of colonic inflammatory responses by UDCA and to determine the potential impact of bacterial metabolism on its therapeutic actions. The anti-inflammatory efficacy of UDCA, a nonmetabolizable analog, 6α-methyl-UDCA (6-MUDCA), and its primary colonic metabolite lithocholic acid (LCA) was assessed in the murine dextran sodium sulfate (DSS) model of mucosal injury. The effects of bile acids on cytokine (TNF-α, IL-6, Il-1β, and IFN-γ) release from cultured colonic epithelial cells and mouse colonic tissue in vivo were investigated. Luminal bile acids were measured by gas chromatography-mass spectrometry. UDCA attenuated release of proinflammatory cytokines from colonic epithelial cells in vitro and was protective against the development of colonic inflammation in vivo. In contrast, although 6-MUDCA mimicked the effects of UDCA on epithelial cytokine release in vitro, it was ineffective in preventing inflammation in the DSS model. In UDCA-treated mice, LCA became the most common colonic bile acid. Finally, LCA treatment more potently inhibited epithelial cytokine release and protected against DSS-induced mucosal inflammation than did UDCA. These studies identify a new role for the primary metabolite of UDCA, LCA, in preventing colonic

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.

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.

A sucrose-rich diet induces mutations in the rat colon

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Dragsted, L.O.; Daneshvar, B.; Vogel, Ulla Birgitte

2002-01-01

A sucrose-rich diet has repeatedly been observed to have cocarcinogenic actions in the colon and liver of rats and to increase the number of aberrant crypt foci in rat colon. To investigate whether sucrose-rich diets might directly increase the genotoxic response in the rat colon or liver, we have...... or in blood plasma. We conclude that a sucrose-rich diet directly or indirectly increases the mutation frequency in rat colon in a dose-dependent manner and concomitantly decreases the level of background DNA adducts, without a direct effect on the expression of major DNA repair enzyme systems. We also...... conclude that an oxidative mechanism for this effect of sucrose is unlikely. This is the first demonstration of a genotoxic action of increased dietary sucrose in vivo. Both sucrose intake and colon cancer rates are high in the Western world, and our present results call for an examination of a possible...

Effects of cyclooxygenase and lipoxygenase inhibition on basal- and serotonin-induced ion transport in rat colon

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Engelmann, Bodil Elisabeth; Bindslev, Niels; Poulsen, Steen Seier

2002-01-01

basal conditions. Furthermore, data suggest neither the COX-1 nor the COX-2 enzyme to be of major importance for 5-HT-induced ion transport in rat colon in vitro. In conclusion, this study supports 5-HT as a mediator of chloride secretion by activating several receptor subtypes and the LOX enzyme...

Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis.

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Choi, Youngshim; Abdelmegeed, Mohamed A; Song, Byoung-Joon

2018-05-01

Indole-3-carbinol (I3C), found in Brassica family vegetables, exhibits antioxidant, anti-inflammatory, and anti-cancerous properties. Here, we aimed to evaluate the preventive effects of I3C against ethanol (EtOH)-induced liver injury and study the protective mechanism(s) by using the well-established chronic-plus-binge alcohol exposure model. The preventive effects of I3C were evaluated by conducting various histological, biochemical, and real-time PCR analyses in mouse liver, adipose tissue, and colon, since functional alterations of adipose tissue and intestine can also participate in promoting EtOH-induced liver damage. Daily treatment with I3C alleviated EtOH-induced liver injury and hepatocyte apoptosis, but not steatosis, by attenuating elevated oxidative stress, as evidenced by the decreased levels of hepatic lipid peroxidation, hydrogen peroxide, CYP2E1, NADPH-oxidase, and protein acetylation with maintenance of mitochondrial complex I, II, and III protein levels and activities. I3C also restored the hepatic antioxidant capacity by preventing EtOH-induced suppression of glutathione contents and mitochondrial aldehyde dehydrogenase-2 activity. I3C preventive effects were also achieved by attenuating the increased levels of hepatic proinflammatory cytokines, including IL1β, and neutrophil infiltration. I3C also attenuated EtOH-induced gut leakiness with decreased serum endotoxin levels through preventing EtOH-induced oxidative stress, apoptosis of enterocytes, and alteration of tight junction protein claudin-1. Furthermore, I3C alleviated adipose tissue inflammation and decreased free fatty acid release. Collectively, I3C prevented EtOH-induced liver injury via attenuating the damaging effect of ethanol on the gut-liver-adipose tissue axis. Therefore, I3C may also have a high potential for translational research in treating or preventing other types of hepatic injury associated with oxidative stress and inflammation. Copyright © 2017 Elsevier Inc. All

H2S-induced S-sulfhydration of lactate dehydrogenase a (LDHA) stimulates cellular bioenergetics in HCT116 colon cancer cells.

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Untereiner, Ashley A; Oláh, Gabor; Módis, Katalin; Hellmich, Mark R; Szabo, Csaba

2017-07-15

Cystathionine-β-synthase (CBS) is upregulated and hydrogen sulfide (H 2 S) production is increased in colon cancer cells. The functional consequence of this response is stimulation of cellular bioenergetics and tumor growth and proliferation. Lactate dehydrogenase A (LDHA) is also upregulated in various colon cancer cells and has been previously implicated in tumor cell bioenergetics and proliferation. In the present study, we sought to determine the potential interaction between the H 2 S pathway and LDH activity in the control of bioenergetics and proliferation of colon cancer, using the colon cancer line HCT116. Low concentrations of GYY4137 (a slow-releasing H 2 S donor) enhanced mitochondrial function (oxygen consumption, ATP production, and spare respiratory capacity) and glycolysis in HCT116 cells. SiRNA-mediated transient silencing of LDHA attenuated the GYY4137-induced stimulation of mitochondrial respiration, but not of glycolysis. H 2 S induced the S-sulfhydration of Cys163 in recombinant LDHA, and stimulated LDHA activity. The H 2 S-induced stimulation of LDHA activity was absent in C163A LDHA. As shown in HCT116 cell whole extracts, in addition to LDHA activation, GYY4137 also stimulated LDHB activity, although to a smaller extent. Total cellular lactate and pyruvate measurements showed that in HCT116 cells LDHA catalyzes the conversion of pyruvate to lactate. Total cellular lactate levels were increased by GYY4137 in wild-type cells (but not in cells with LDHA silencing). LDHA silencing sensitized HCT116 cells to glucose oxidase (GOx)-induced oxidative stress; this was further exacerbated with GYY4137 treatment. Treatment with low concentrations of GYY4137 (0.3mM) or GOx (0.01U/ml) significantly increased the proliferation rate of HCT116 cells; the effect of GOx, but not the effect of GYY4137 was attenuated by LDHA silencing. The current report points to the involvement of LDHA in the stimulatory effect of H 2 S on mitochondrial respiration in colon

8-C-(E-phenylethenyl)quercetin from onion/beef soup induces autophagic cell death in colon cancer cells through ERK activation.

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Zhao, Yueliang; Fan, Daming; Zheng, Zong-Ping; Li, Edmund T S; Chen, Feng; Cheng, Ka-Wing; Wang, Mingfu

2017-02-01

Quercetin, a flavonoid, widely distributed in edible fruits and vegetables, was reported to effectively inhibit 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (PhIP) formation in a food model (roast beef patties) with itself being converted into a novel compound 8-C-(E-phenylethenyl)quercetin (8-CEPQ). Here we investigated whether 8-CEPQ could be formed in a real food system, and tested its anticancer activity in human colon cancer cell lines. LC-MS was applied for the determination of 8-CEPQ formation in onion/beef soup. Anticancer activity of 8-CEPQ was evaluated by using cell viability assay and flow cytometry. Results showed that 8-CEPQ suppressed proliferation and caused G 2 phase arrest in colon cancer cells. Based on immunofluorescent staining assay, western blot assay, and RNA knockdown data, we found that 8-CEPQ did not cause apoptotic cell death. Instead, it induced autophagic cell death. Moreover, treatment with 8-CEPQ induced phosphorylation of extracellular signal-regulated kinase (ERK). Inhibition of ERK phosphorylation by the mitogen-activated protein kinase kinase (MEK)/ERK inhibitor U0126 attenuated 8-CEPQ-induced autophagy and reversed 8-CEPQ-mediated cell growth inhibition. Our results demonstrate that 8-CEPQ, a novel quercetin derivative, could be formed in onion/beef soup. 8-CEPQ inhibited colon cancer cell growth by inducing autophagic cell death through ERK activation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isoliquiritigenin, a flavonoid from licorice, blocks M2 macrophage polarization in colitis-associated tumorigenesis through downregulating PGE{sub 2} and IL-6

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Zhao, Haixia [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Zhang, Xinhua [Department of Liver, Biliary And Pancreatic Tumors, Hubei Cancer Hospital, Wuhan 430079 (China); Chen, Xuewei; Li, Ying; Ke, Zunqiong [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Tang, Tian [Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Chai, Hongyan [Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan 430071 (China); Guo, Austin M. [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Department of Pharmacology, New York Medical College, Valhalla, NY 10595 (United States); Chen, Honglei, E-mail: hl-chen@whu.edu.cn [Department of Pathology and Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China)

2014-09-15

M2 macrophage polarization is implicated in colorectal cancer development. Isoliquiritigenin (ISL), a flavonoid from licorice, has been reported to prevent azoxymethane (AOM) induced colon carcinogenesis in animal models. Here, in a mouse model of colitis-associated tumorigenesis induced by AOM/dextran sodium sulfate (DSS), we investigated the chemopreventive effects of ISL and its mechanisms of action. Mice were treated with AOM/DSS and randomized to receive either vehicle or ISL (3, 15 and 75 mg/kg). Tumor load, histology, immunohistochemistry, and gene and protein expressions were determined. Intragastric administration of ISL for 12 weeks significantly decreased colon cancer incidence, multiplicity and tumor size by 60%, 55.4% and 42.6%, respectively. Moreover, ISL inhibited M2 macrophage polarization. Such changes were accompanied by downregulation of PGE{sub 2} and IL-6 signaling. Importantly, depletion of macrophages by clodronate (Clod) or zoledronic acid (ZA) reversed the effects of ISL. In parallel, in vitro studies also demonstrated that ISL limited the M2 polarization of RAW264.7 cells and mouse peritoneal macrophages with concomitant inactivation of PGE{sub 2}/PPARδ and IL-6/STAT3 signaling. Conversely, exogenous addition of PGE{sub 2} or IL-6, or overexpression of constitutively active STAT3 reversed ISL-mediated inhibition of M2 macrophage polarization. In summary, dietary flavonoid ISL effectively inhibits colitis-associated tumorigenesis through hampering M2 macrophage polarization mediated by the interplay between PGE{sub 2} and IL-6. Thus, inhibition of M2 macrophage polarization is likely to represent a promising strategy for chemoprevention of colorectal cancer. - Highlights: • Isoliquiritigenin (ISL) prevents colitis-associated tumorigenesis. • ISL inhibits M2 macrophage polarization in vivo and in vitro. • ISL inhibits PGE{sub 2} and IL-6 signaling in colitis-associated tumorigenesis. • ISL may be an attractive candidate agent for

Optimization of visibility and quantification of aberrant crypt foci in colonic mucosa in Wistar rats Otimização da visibilidade e quantificação de focos de criptas aberrantes em mucosa cólica de ratos Wistar

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Idália Maria Brasil Burlamaqui

2010-04-01

Full Text Available PURPOSE: Test immersion of microscopy samples in water as an aid to visualizing and quantifying aberrant crypt foci (ACF in rat colon mucosa. METHODS: Carcinogenesis was induced with azoxymethane in Wistar rats kept on a conventional diet or a hypercaloric diet containing unsaturated fat. Fifteen weeks after induction, colon samples were retrieved and fixated in a 10% formaldehyde solution. The samples were divided into segments (distal, middle, proximal and stained with 1% toluidine blue. The technique tested in the study consisted of immersing microscopy samples in distilled water in order to eliminate the problem of light reflection known from conventional microscopy. RESULTS: When samples were immersed in water during microscopy, significantly more ACF could be visualized in all colon segments than with the conventional method proposed by Bird. CONCLUSION: Immersing microscopy samples in water aids the visualization and quantification of aberrant crypt foci in rat colon mucosa fixed in formaldehyde.OBJETIVO: Otimizar a visibilização de focos de criptas aberrantes (FCA em mucosa cólica de ratos Wistar. MÉTODOS: Colo de rato Wistar, sob diferentes dietas e submetidos a iniciação de carcinogênese pelo azoximetano há 4 meses, foram previamente lavados, abertos e fixados em solução de formalina a 10% por 24 horas. Após serem corados em azul de toluidina a 1%, foram divididos em segmentos distal, médio e proximal e imersos em água destilada para quantificação de FCA. RESULTADOS: No método de imersão foi visibilizado maior quantidade de focos de criptas aberrantes em todos os segmentos cólicos, com diferença significante, quando comparado com o método de Bird. CONCLUSÃO: O método de imersão otimiza a visibilização e quantificação de focos de criptas aberrantes em mucosa cólica (ratos Wistar fixada em solução de formalina a 10%.

Perinatal supplementation of 4-phenylbutyrate and glutamine attenuates endoplasmic reticulum stress and improves colonic epithelial barrier function in rats born with intrauterine growth restriction.

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Désir-Vigné, Axel; Haure-Mirande, Vianney; de Coppet, Pierre; Darmaun, Dominique; Le Dréan, Gwenola; Segain, Jean-Pierre

2018-05-01

Intrauterine growth restriction (IUGR) can affect the structure and function of the intestinal barrier and increase digestive disease risk in adulthood. Using the rat model of maternal dietary protein restriction (8% vs. 20%), we found that the colon of IUGR offspring displayed decreased mRNA expression of epithelial barrier proteins MUC2 and occludin during development. This was associated with increased mRNA expression of endoplasmic reticulum (ER) stress marker XBP1s and increased colonic permeability measured in Ussing chambers. We hypothesized that ER stress contributes to colonic barrier alterations and that perinatal supplementation of dams with ER stress modulators, phenylbutyrate and glutamine (PG) could prevent these defects in IUGR offspring. We first demonstrated that ER stress induction by tunicamycin or thapsigargin increased the permeability of rat colonic tissues mounted in Ussing chamber and that PG treatment prevented this effect. Therefore, we supplemented the diet of control and IUGR dams with PG during gestation and lactation. Real-time polymerase chain reaction and histological analysis of colons from 120-day-old offspring revealed that perinatal PG treatment partially prevented the increased expression of ER stress markers but reversed the reduction of crypt depth and goblet cell number in IUGR rats. In dextran sodium sulfate-induced injury and recovery experiments, the colon of IUGR rats without perinatal PG treatment showed higher XBP1s mRNA levels and histological scores of inflammation than IUGR rats with perinatal PG treatment. In conclusion, these data suggest that perinatal supplementation with PG could alleviate ER stress and prevent epithelial barrier dysfunction in IUGR offspring. Copyright © 2017 Elsevier Inc. All rights reserved.

Metformin and berberine prevent olanzapine-induced weight gain in rats.

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Yueshan Hu

Full Text Available Olanzapine is a first line medication for the treatment of schizophrenia, but it is also one of the atypical antipsychotics carrying the highest risk of weight gain. Metformin was reported to produce significant attenuation of antipsychotic-induced weight gain in patients, while the study of preventing olanzapine-induced weight gain in an animal model is absent. Berberine, an herbal alkaloid, was shown in our previous studies to prevent fat accumulation in vitro and in vivo. Utilizing a well-replicated rat model of olanzapine-induced weight gain, here we demonstrated that two weeks of metformin or berberine treatment significantly prevented the olanzapine-induced weight gain and white fat accumulation. Neither metformin nor berberine treatment demonstrated a significant inhibition of olanzapine-increased food intake. But interestingly, a significant loss of brown adipose tissue caused by olanzapine treatment was prevented by the addition of metformin or berberine. Our gene expression analysis also demonstrated that the weight gain prevention efficacy of metformin or berberine treatment was associated with changes in the expression of multiple key genes controlling energy expenditure. This study not only demonstrates a significant preventive efficacy of metformin and berberine treatment on olanzapine-induced weight gain in rats, but also suggests a potential mechanism of action for preventing olanzapine-reduced energy expenditure.

The natural triterpene maslinic acid induces apoptosis in HT29 colon cancer cells by a JNK-p53-dependent mechanism

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Reyes-Zurita, Fernando J; Pachón-Peña, Gisela; Lizárraga, Daneida; Rufino-Palomares, Eva E; Cascante, Marta; Lupiáñez, José A

2011-01-01

Maslinic acid, a pentacyclic triterpene found in the protective wax-like coating of the leaves and fruit of Olea europaea L., is a promising agent for the prevention of colon cancer. We have shown elsewhere that maslinic acid inhibits cell proliferation to a significant extent and activates mitochondrial apoptosis in colon cancer cells. In our latest work we have investigated further this compound's apoptotic molecular mechanism. We used HT29 adenocarcinoma cells. Changes genotoxicity were analyzed by single-cell gel electrophoresis (comet assay). The cell cycle was determined by flow cytometry. Finally, changes in protein expression were examined by western blotting. Student's t-test was used for statistical comparison. HT29 cells treated with maslinic acid showed significant increases in genotoxicity and cell-cycle arrest during the G0/G1 phase after 72 hours' treatment and an apoptotic sub-G0/G1 peak after 96 hours. Nevertheless, the molecular mechanism for this cytotoxic effect of maslinic acid has never been properly explored. We show here that the anti-tumoral activity of maslinic acid might proceed via p53-mediated apoptosis by acting upon the main signaling components that lead to an increase in p53 activity and the induction of the rest of the factors that participate in the apoptotic pathway. We found that in HT29 cells maslinic acid activated the expression of c-Jun NH2-terminal kinase (JNK), thus inducing p53. Treatment of tumor cells with maslinic acid also resulted in an increase in the expression of Bid and Bax, repression of Bcl-2, release of cytochrome-c and an increase in the expression of caspases -9, -3, and -7. Moreover, maslinic acid produced belated caspase-8 activity, thus amplifying the initial mitochondrial apoptotic signaling. All these results suggest that maslinic acid induces apoptosis in human HT29 colon-cancer cells through the JNK-Bid-mediated mitochondrial apoptotic pathway via the activation of p53. Thus we propose

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

Thrombospondin-1 in a Murine Model of Colorectal Carcinogenesis.

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Zenaida P Lopez-Dee

Full Text Available Colorectal Cancer (CRC is one of the late complications observed in patients suffering from inflammatory bowel diseases (IBD. Carcinogenesis is promoted by persistent chronic inflammation occurring in IBD. Understanding the mechanisms involved is essential in order to ameliorate inflammation and prevent CRC. Thrombospondin 1 (TSP-1 is a multidomain glycoprotein with important roles in angiogenesis. The effects of TSP-1 in colonic tumor formation and growth were analyzed in a model of inflammation-induced carcinogenesis. WT and TSP-1 deficient mice (TSP-1-/- of the C57BL/6 strain received a single injection of azoxymethane (AOM and multiple cycles of dextran sodium sulfate (DSS to induce chronic inflammation-related cancers. Proliferation and angiogenesis were histologically analyzed in tumors. The intestinal transcriptome was also analyzed using a gene microarray approach. When the area containing tumors was compared with the entire colonic area of each mouse, the tumor burden was decreased in AOM/DSS-treated TSP-1-/- versus wild type (WT mice. However, these lesions displayed more angiogenesis and proliferation rates when compared with the WT tumors. AOM-DSS treatment of TSP-1-/- mice resulted in significant deregulation of genes involved in transcription, canonical Wnt signaling, transport, defense response, regulation of epithelial cell proliferation and metabolism. Microarray analyses of these tumors showed down-regulation of 18 microRNAs in TSP-1-/- tumors. These results contribute new insights on the controversial role of TSP-1 in cancer and offer a better understanding of the genetics and pathogenesis of CRC.

Hypoxia-inducible factor 1-alpha up-regulates the expression of phospholipase D2 in colon cancer cells under hypoxic conditions.

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

2015-01-01

Hypoxia is a common characteristic of solid tumors. Recent studies confirmed that phospholipase D2 (PLD2) plays significant roles in cancer progression. In this study, correlation between the expression of PLD2 and the change in the protein level of hypoxia-inducible factor 1-alpha (HIF1-α) was studied. Thirty human colon cancer tissues were examined for the expression of HIF1-α and PLD2 protein, and mRNA levels. SW480 and SW620 cells were exposed to normoxia (20 %) or hypoxia (Hypoxic stress induced PLD2 mRNA and protein expression in SW480 and SW620 cells. Cells transfected with HIF1-α siRNA showed attenuation of hypoxia stress-induced PLD2 expression. In vivo growth decreased in response to HIF1-α and PLD2 inhibition. These results suggest that PLD2 expression in colon cancer cells is up-regulated via HIF1-α in response to hypoxic stress and underscores the crucial role of HIF1-α-induced PLD2 in tumor growth.

Betulinic acid inhibits colon cancer cell and tumor growth and induces proteasome-dependent and -independent downregulation of specificity proteins (Sp transcription factors

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Pathi Satya

2011-08-01

Full Text Available Abstract Background Betulinic acid (BA inhibits growth of several cancer cell lines and tumors and the effects of BA have been attributed to its mitochondriotoxicity and inhibition of multiple pro-oncogenic factors. Previous studies show that BA induces proteasome-dependent degradation of specificity protein (Sp transcription factors Sp1, Sp3 and Sp4 in prostate cancer cells and this study focused on the mechanism of action of BA in colon cancer cells. Methods The effects of BA on colon cancer cell proliferation and apoptosis and tumor growth in vivo were determined using standardized assays. The effects of BA on Sp proteins and Sp-regulated gene products were analyzed by western blots, and real time PCR was used to determine microRNA-27a (miR-27a and ZBTB10 mRNA expression. Results BA inhibited growth and induced apoptosis in RKO and SW480 colon cancer cells and inhibited tumor growth in athymic nude mice bearing RKO cells as xenograft. BA also decreased expression of Sp1, Sp3 and Sp4 transcription factors which are overexpressed in colon cancer cells and decreased levels of several Sp-regulated genes including survivin, vascular endothelial growth factor, p65 sub-unit of NFκB, epidermal growth factor receptor, cyclin D1, and pituitary tumor transforming gene-1. The mechanism of action of BA was dependent on cell context, since BA induced proteasome-dependent and proteasome-independent downregulation of Sp1, Sp3 and Sp4 in SW480 and RKO cells, respectively. In RKO cells, the mechanism of BA-induced repression of Sp1, Sp3 and Sp4 was due to induction of reactive oxygen species (ROS, ROS-mediated repression of microRNA-27a, and induction of the Sp repressor gene ZBTB10. Conclusions These results suggest that the anticancer activity of BA in colon cancer cells is due, in part, to downregulation of Sp1, Sp3 and Sp4 transcription factors; however, the mechanism of this response is cell context-dependent.

Betulinic acid inhibits colon cancer cell and tumor growth and induces proteasome-dependent and -independent downregulation of specificity proteins (Sp) transcription factors

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Chintharlapalli, Sudhakar; Papineni, Sabitha; Lei, Ping; Pathi, Satya; Safe, Stephen

2011-01-01

Betulinic acid (BA) inhibits growth of several cancer cell lines and tumors and the effects of BA have been attributed to its mitochondriotoxicity and inhibition of multiple pro-oncogenic factors. Previous studies show that BA induces proteasome-dependent degradation of specificity protein (Sp) transcription factors Sp1, Sp3 and Sp4 in prostate cancer cells and this study focused on the mechanism of action of BA in colon cancer cells. The effects of BA on colon cancer cell proliferation and apoptosis and tumor growth in vivo were determined using standardized assays. The effects of BA on Sp proteins and Sp-regulated gene products were analyzed by western blots, and real time PCR was used to determine microRNA-27a (miR-27a) and ZBTB10 mRNA expression. BA inhibited growth and induced apoptosis in RKO and SW480 colon cancer cells and inhibited tumor growth in athymic nude mice bearing RKO cells as xenograft. BA also decreased expression of Sp1, Sp3 and Sp4 transcription factors which are overexpressed in colon cancer cells and decreased levels of several Sp-regulated genes including survivin, vascular endothelial growth factor, p65 sub-unit of NFκB, epidermal growth factor receptor, cyclin D1, and pituitary tumor transforming gene-1. The mechanism of action of BA was dependent on cell context, since BA induced proteasome-dependent and proteasome-independent downregulation of Sp1, Sp3 and Sp4 in SW480 and RKO cells, respectively. In RKO cells, the mechanism of BA-induced repression of Sp1, Sp3 and Sp4 was due to induction of reactive oxygen species (ROS), ROS-mediated repression of microRNA-27a, and induction of the Sp repressor gene ZBTB10. These results suggest that the anticancer activity of BA in colon cancer cells is due, in part, to downregulation of Sp1, Sp3 and Sp4 transcription factors; however, the mechanism of this response is cell context-dependent

Evaluation of Nanocarrier Targeted Drug Delivery of Capecitabine-PAMAM Dendrimer Complex in a Mice Colorectal Cancer Model

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Fatemeh Nabavizadeh

2016-09-01

Full Text Available Capecitabine, an effective anticancer drug in colorectal cancer chemotherapy, may create adverse side effects on healthy tissues. In the present study, we first induced colon adenocarcinoma with azoxymethane, a carcinogen agent, and then investigated the potentiality of polyamidoamine (PAMAM dendrimer to improve capecitabine therapeutic index and decrease its adverse side effects on healthy tissues like liver and bone marrow. Other variables such as nanoparticle concentrations have also been investigated. Drug loading concentration (DLC and encapsulation efficiency (EE were calculated for capecitabine/dendrimer complex. Experimental results showed an increase in DLC percentage resulted from elevated capecitabine/dendrimer ratio. Capecitabine/dendrimer complex could reduce tumor size and adverse side effects in comparison with free capecitabine form.

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.

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.

Vasohibin-1 suppresses colon cancer

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Liu, Shuai; Han, Bing; Zhang, Qunyuan; Dou, Jie; Wang, Fang; Lin, Wenli; Sun, Yuping; Peng, Guangyong

2015-01-01

Vasohibin-1 (VASH1) is an endogenous angiogenesis inhibitor. However, the clinical relevance of VASH1 in colon cancer and its regulations on cancer angiogenesis and cancer cell biological characteristics are still unknown. Here we showed that stromal VASH1 levels were negatively correlated with tumor size, advanced clinical stage and distant metastases in colon cancer patients. Overexpression of VASH1 in colon cancer cells induced apoptosis and senescence, inhibiting cancer cell growth and colony formation in vitro and tumor growth in vivo. In addition, knockdown of VASH1 in cancer cells promoted cell growth, adhesion and migration in vitro, and enhanced tumorigenesis and metastasis in vivo. PMID:25797264

Vasohibin-1 suppresses colon cancer.

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Liu, Shuai; Han, Bing; Zhang, Qunyuan; Dou, Jie; Wang, Fang; Lin, Wenli; Sun, Yuping; Peng, Guangyong

2015-04-10

Vasohibin-1 (VASH1) is an endogenous angiogenesis inhibitor.However, the clinical relevance of VASH1 in colon cancer and its regulations on cancer angiogenesis and cancer cell biological characteristics are still unknown. Here we showed that stromal VASH1 levels were negatively correlated with tumor size, advanced clinical stage and distant metastases in colon cancer patients. Overexpression of VASH1 in colon cancer cells induced apoptosis and senescence, inhibiting cancer cell growth and colony formation in vitro and tumor growth in vivo. In addition, knockdown of VASH1 in cancer cells promoted cell growth, adhesion and migration in vitro, and enhanced tumorigenesis and metastasis in vivo.

Antithrombin III prevents deleterious effects of remote ischemia-reperfusion injury on healing of colonic anastomoses.

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Tekin, Koray; Aytekin, Faruk; Ozden, Akin; Bilgihan, Ayşe; Erdem, Ergün; Sungurtekin, Ugur; Güney, Yildiz

2002-08-01

Antithrombin III is known as the most important natural inhibitor of thrombin activity and has been shown to attenuate local harmful effects of ischemia-reperfusion injury in many organs. In recent animal studies, delaying effect of remote organ ischemia-reperfusion injury on healing of intestinal anastomoses has been demonstrated. In this study, we investigated whether antithrombin III reduces deleterious systemic effects of ischemia-reperfusion injury on healing of colonic anastomoses in rats. Anastomosis of the left colon was performed in 24 rats that were divided into three groups: sham operated control (group I, n = 8), 30 minutes of intestinal ischemia-reperfusion by superior mesenteric artery occlusion (group II, n = 8), antithrombin III treated group (250 U/kg before and after the ischemia-reperfusion, group III, n = 8). On postoperative day 6, all animals were sacrificed, and bursting pressure and tissue hydroxyproline content of the anastomoses were assessed and compared. On postoperative day 6 the mean bursting pressures were 149.6 +/- 4.8, 69.8 +/- 13.5, and 121.8 +/- 8.7 mm Hg for groups I, II, and III, respectively (P = 0.000). Mean tissue hydroxyproline concentration values were 389.5 +/- 29.6, 263.1 +/- 10.0, and 376.0 +/- 33.8 microg/mg for groups I, II, III respectively (P = 0.005). This study showed that, antithrombin III treatment significantly prevented the delaying effect of remote organ ischemia-reperfusion injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether antithrombin may be a useful therapeutic agent to increase the safety of the anastomosis during particular operations where remote organ ischemia-reperfusion injury takes place.

Mast Cell Targeted Chimeric Toxin Can Be Developed as an Adjunctive Therapy in Colon Cancer Treatment

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Shan Wang

2016-03-01

Full Text Available The association of colitis with colorectal cancer has become increasingly clear with mast cells being identified as important inflammatory cells in the process. In view of the relationship between mast cells and cancer, we studied the effect and mechanisms of mast cells in the development of colon cancer. Functional and mechanistic insights were gained from ex vivo and in vivo studies of cell interactions between mast cells and CT26 cells. Further evidence was reversely obtained in studies of mast cell targeted Fcε-PE40 chimeric toxin. Experiments revealed mast cells could induce colon tumor cell proliferation and invasion. Cancer progression was found to be related to the density of mast cells in colonic submucosa. The activation of MAPK, Rho-GTPase, and STAT pathways in colon cancer cells was triggered by mast cells during cell-to-cell interaction. Lastly, using an Fcε-PE40 chimeric toxin we constructed, we confirmed the promoting effect of mast cells in development of colon cancer. Mast cells are a promoting factor of colon cancer and thus also a potential therapeutic target. The Fcε-PE40 chimeric toxin targeting mast cells could effectively prevent colon cancer in vitro and in vivo. Consequently, these data may demonstrate a novel immunotherapeutic approach for the treatment of tumors.

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

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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.

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.

A Ketogenic Formula Prevents Tumor Progression and Cancer Cachexia by Attenuating Systemic Inflammation in Colon 26 Tumor-Bearing Mice

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Kentaro Nakamura

2018-02-01

Full Text Available Low-carbohydrate, high-fat diets (ketogenic diets might prevent tumor progression and could be used as supportive therapy; however, few studies have addressed the effect of such diets on colorectal cancer. An infant formula with a ketogenic composition (ketogenic formula; KF is used to treat patients with refractory epilepsy. We investigated the effect of KF on cancer and cancer cachexia in colon tumor-bearing mice. Mice were randomized into normal (NR, tumor-bearing (TB, and ketogenic formula (KF groups. Colon 26 cells were inoculated subcutaneously into TB and KF mice. The NR and TB groups received a standard diet, and the KF mice received KF ad libitum. KF mice preserved their body, muscle, and carcass weights. Tumor weight and plasma IL-6 levels were significantly lower in KF mice than in TB mice. In the KF group, energy intake was significantly higher than that in the other two groups. Blood ketone body concentrations in KF mice were significantly elevated, and there was a significant negative correlation between blood ketone body concentration and tumor weight. Therefore, KF may suppress the progression of cancer and the accompanying systemic inflammation without adverse effects on weight gain, or muscle mass, which might help to prevent cancer cachexia.

Genetic responses induced in olive roots upon colonization by the biocontrol endophytic bacterium Pseudomonas fluorescens PICF7.

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Elisabetta Schilirò

Full Text Available Knowledge on the genetic basis underlying interactions between beneficial bacteria and woody plants is still very limited, and totally absent in the case of olive. We aimed to elucidate genetic responses taking place during the colonization of olive roots by the native endophyte Pseudomonas fluorescens PICF7, an effective biocontrol agent against Verticillium wilt of olive. Roots of olive plants grown under non-gnotobiotic conditions were collected at different time points after PICF7 inoculation. A Suppression Subtractive Hybridization cDNA library enriched in induced genes was generated. Quantitative real time PCR (qRT-PCR analysis validated the induction of selected olive genes. Computational analysis of 445 olive ESTs showed that plant defence and response to different stresses represented nearly 45% of genes induced in PICF7-colonized olive roots. Moreover, quantitative real-time PCR (qRT-PCR analysis confirmed induction of lipoxygenase, phenylpropanoid, terpenoids and plant hormones biosynthesis transcripts. Different classes of transcription factors (i.e., bHLH, WRKYs, GRAS1 were also induced. This work highlights for the first time the ability of an endophytic Pseudomonas spp. strain to mount a wide array of defence responses in an economically-relevant woody crop such as olive, helping to explain its biocontrol activity.

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.

Colonic motor dysfunctions in a mouse model of high-fat diet-induced obesity: an involvement of A2B adenosine receptors.

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Antonioli, Luca; Pellegrini, Carolina; Fornai, Matteo; Tirotta, Erika; Gentile, Daniela; Benvenuti, Laura; Giron, Maria Cecilia; Caputi, Valentina; Marsilio, Ilaria; Orso, Genny; Bernardini, Nunzia; Segnani, Cristina; Ippolito, Chiara; Csóka, Balázs; Németh, Zoltán H; Haskó, György; Scarpignato, Carmelo; Blandizzi, Corrado; Colucci, Rocchina

2017-12-01

Adenosine A 2B receptors (A 2B R) regulate several enteric functions. However, their implication in the pathophysiology of intestinal dysmotility associated with high-fat diet (HFD)-induced obesity has not been elucidated. We investigated the expression of A 2B R in mouse colon and their role in the mechanisms underlying the development of enteric dysmotility associated with obesity. Wild-type C57BL/6J mice were fed with HFD (60% kcal from fat) or normocaloric diet (NCD; 18% kcal from fat) for 8 weeks. Colonic A 2B R localization was examined by immunofluorescence. The role of A 2B R in the control of colonic motility was examined in functional experiments on longitudinal muscle preparations (LMPs). In NCD mice, A 2B R were predominantly located in myenteric neurons; in HFD animals, their expression increased throughout the neuromuscular layer. Functionally, the A 2B R antagonist MRS1754 enhanced electrically induced NK 1 -mediated tachykininergic contractions in LMPs from HFD mice, while it was less effective in tissues from NCD mice. The A 2B receptor agonist BAY 60-6583 decreased colonic tachykininergic contractions in LMPs, with higher efficacy in preparations from obese mice. Both A 2B R ligands did not affect contractions elicited by exogenous substance P. Obesity is related with a condition of colonic inflammation, leading to an increase of A 2B R expression. A 2B R, modulating the activity of excitatory tachykininergic nerves, participate to the enteric dysmotility associated with obesity.

Early Administration of Probiotics Alters Bacterial Colonization and Limits Diet-Induced Gut Dysfunction and Severity of Necrotizing Enterocolitis in Preterm Pigs

DEFF Research Database (Denmark)

Siggers, Richard H.; Siggers, Jayda; Boye, Mette

2008-01-01

Following preterm birth, bacterial colonization and interal formula feeding predispose neonates to gut dysfunction and necrotizing enterocilitis (NEC), a serious gastrointestinal inflammatory disease. We hypothesized that administration of probiotics would beneficially influence early bacterial...... colonization, thereby reducing the susceptibility to formula-induced gut atrophy, dysfunction, and NEC. Caesarean-delivered preterm pigs were provided total parenteral nutrition (1.5 d) followed by enteral feeding (2d) with porcine colosstrum (COLOS; n= 5), formula (FORM; n = 9), or formula with probiotics...

Colon distension and scan protocol for CT-colonography: an overview

NARCIS (Netherlands)

Boellaard, Thierry N.; de Haan, Margriet C.; Venema, Henk W.; Stoker, Jaap

2013-01-01

This article reviews two important aspects of CT-colonography, namely colonic distension and scan parameters. Adequate distension should be obtained to visualize the complete colonic lumen and optimal scan parameters should be used to prevent unnecessary radiation burden. For optimal distension,

Impact of Dietary Galacto-Oligosaccharide (GOS) on Chicken’s Gut Microbiota, Mucosal Gene Expression, and Salmonella Colonization

OpenAIRE

Rebecca-Ayme Hughes; Rebecca-Ayme Hughes; Riawana A. Ali; Mary A. Mendoza; Hosni M. Hassan; Matthew D. Koci

2017-01-01

Preventing Salmonella colonization in young birds is key to reducing contamination of poultry products for human consumption (eggs and meat). While several Salmonella vaccines have been developed that are capable of yielding high systemic antibodies, it is not clear how effective these approaches are at controlling or preventing Salmonella colonization of the intestinal tract. Effective alternative control strategies are needed to help supplement the bird’s ability to prevent Salmonella colon...

Age-related loss of EGF-receptor related protein (ERRP) in the aging colon is a potential risk factor for colon cancer.

Science.gov (United States)

Schmelz, Eva M; Levi, Edi; Du, Jianhua; Xu, Hu; Majumdar, Adhip P N

2004-12-01

Although in Fischer-344 rats, aging is associated with increased activation of EGF-receptor (EGFR) in mucosa of much of the gastrointestinal tract, including the colon, regulation of this process is poorly understood. We hypothesize that loss of suppressor of EGFR may partly be responsible for this process. To test this hypothesis, we examined the expression of EGFR related protein (ERRP), a recently identified negative regulator of EGFR, in the colonic mucosa during aging and following administration of the colonic carcinogen dimethylhydrazine (DMH) that resulted in the formation of aberrant crypt foci (ACF), which are considered to be precursor of adenoma and carcinoma. In Fischer-344 rats, aging is associated with increased activation of EGFR in the colonic mucosa, as evidenced by 30-35% increase in the levels of tyrosine phosphorylated EGFR in the proximal and distal colon of aged (20-22 months old) than in young (4-6 months old) rats. In contrast, the levels of ERRP in both regions of the colon of aged rats were decreased by 50-60%, compared to their younger counterparts. Administration of DMH, which induced a greater number of ACF in the colon of aged rats than in young animals, resulted in a corresponding reduction in ERRP in the colon. These results suggest that loss of ERRP expression is a common event during aging and early stages of chemically induced colon cancer. We also suggest that loss of ERRP could be a risk factor for developing colorectal cancer in the older population.

Snake venom toxin from vipera lebetina turanica induces apoptosis of colon cancer cells via upregulation of ROS- and JNK-mediated death receptor expression

International Nuclear Information System (INIS)

Park, Mi Hee; Jo, MiRan; Won, Dohee; Song, Ho Sueb; Han, Sang Bae; Song, Min Jong; Hong, Jin Tae

2012-01-01

Abundant research suggested that the cancer cells avoid destruction by the immune system through down-regulation or mutation of death receptors. Therefore, it is very important that finding the agents that increase the death receptors of cancer cells. In this study, we demonstrated that the snake venom toxin from Vipera lebetina turanica induce the apoptosis of colon cancer cells through reactive oxygen species (ROS) and c-Jun N-terminal kinases (JNK) dependent death receptor (DR4 and DR5) expression. We used cell viability assays, DAPI/TUNEL assays, as well as western blot for detection of apoptosis related proteins and DRs to demonstrate that snake venom toxin-induced apoptosis is DR4 and DR5 dependent. We carried out transient siRNA knockdowns of DR4 and DR5 in colon cancer cells. We showed that snake venom toxin inhibited growth of colon cancer cells through induction of apoptosis. We also showed that the expression of DR4 and DR5 was increased by treatment of snake venom toxin. Moreover, knockdown of DR4 or DR5 reversed the effect of snake venom toxin. Snake venom toxin also induced JNK phosphorylation and ROS generation, however, pretreatment of JNK inhibitor and ROS scavenger reversed the inhibitory effect of snake venom toxin on cancer cell proliferation, and reduced the snake venom toxin-induced upregulation of DR4 and DR5 expression. Our results indicated that snake venom toxin could inhibit human colon cancer cell growth, and these effects may be related to ROS and JNK mediated activation of death receptor (DR4 and DR5) signals

Mucins and associated glycan signatures in colon adenoma-carcinoma sequence

DEFF Research Database (Denmark)

Krishn, Shiv Ram; Kaur, Sukhwinder; Smith, Lynette M

2016-01-01

Development of biomarkers that detect early stage resectable premalignant lesions of colon can provide critical aid in the prevention of colorectal cancer. Recent lines of evidence suggest the utility of mucin expression to predict malignant transformation of colon pre-neoplastic lesions. In this...

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.

Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism

International Nuclear Information System (INIS)

Dheer, Rishu; Patterson, Jena; Dudash, Mark; Stachler, Elyse N.; Bibby, Kyle J.; Stolz, Donna B.; Shiva, Sruti; Wang, Zeneng; Hazen, Stanley L.; Barchowsky, Aaron; Stolz, John F.

2015-01-01

Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogenesis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10 weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes. - Highlights: • Arsenic exposure induces changes in host and host nitrogen metabolism that cause progresive change in the microbiome. • A polyphasic approach reveals changes

Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism

Energy Technology Data Exchange (ETDEWEB)

Dheer, Rishu; Patterson, Jena; Dudash, Mark [Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282 (United States); Stachler, Elyse N.; Bibby, Kyle J. [Department of Civil and Environmental Engineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA 15261 (United States); Stolz, Donna B. [Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 (United States); Shiva, Sruti [Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh 15261 (United States); Vascular Medicine Institute, University of Pittsburgh, Pittsburgh 15261 (United States); Wang, Zeneng; Hazen, Stanley L. [Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195 (United States); Barchowsky, Aaron, E-mail: aab20@pitt.edu [Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh 15261 (United States); Vascular Medicine Institute, University of Pittsburgh, Pittsburgh 15261 (United States); Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15219 (United States); Stolz, John F. [Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282 (United States)

2015-12-15

Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogenesis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10 weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes. - Highlights: • Arsenic exposure induces changes in host and host nitrogen metabolism that cause progresive change in the microbiome. • A polyphasic approach reveals changes

Diet-induced obesity elevates colonic TNF-α in mice and is accompanied by an activation of Wnt signaling: a mechanism for obesity-associated colorectal cancer.

Science.gov (United States)

Liu, Zhenhua; Brooks, Ryan S; Ciappio, Eric D; Kim, Susan J; Crott, Jimmy W; Bennett, Grace; Greenberg, Andrew S; Mason, Joel B

2012-10-01

Inflammation associated with obesity may play a role in colorectal carcinogenesis, but the underlying mechanism remains unclear. This study investigated whether the Wnt pathway, an intracellular signaling cascade that plays a critical role in colorectal carcinogenesis, is activated by obesity-induced elevation of the inflammatory cytokine tumor necrosis factor-alpha (TNF-α). Animal studies were conducted on C57BL/6 mice, and obesity was induced by utilizing a high-fat diet (60% kcal). An inflammation-specific microarray was performed, and results were confirmed with real-time polymerase chain reaction. The array revealed that diet-induced obesity increased the expression of TNF-α in the colon by 72% (P=.004) and that of interleukin-18 by 41% (P=.023). The concentration of colonic TNF-α protein, determined by ex vivo culture assay, was nearly doubled in the obese animals (P=.002). The phosphorylation of glycogen synthase kinase 3 beta (GSK3β), an important intermediary inhibitor of Wnt signaling and a potential target of TNF-α, was quantitated by immunohistochemistry. The inactivated (phosphorylated) form of GSK3β was elevated in the colonic mucosa of obese mice (P<.02). Moreover, β-catenin, the key effector of canonical Wnt signaling, was elevated in the colons of obese mice (P<.05), as was the expression of a downstream target gene, c-myc (P<.05). These data demonstrate that diet-induced obesity produces an elevation in colonic TNF-α and instigates a number of alterations of key components within the Wnt signaling pathway that are protransformational in nature. Thus, these observations offer evidence for a biologically plausible avenue, the Wnt pathway, by which obesity increases the risk of colorectal cancer. Copyright © 2012 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

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.

In vitro differentiation of HT-29 M6 mucus-secreting colon cancer cells involves a trychostatin A and p27(KIP1)-inducible transcriptional program of gene expression.

Science.gov (United States)

Mayo, Clara; Lloreta, Josep; Real, Francisco X; Mayol, Xavier

2007-07-01

Tumor cell dedifferentiation-such as the loss of cell-to-cell adhesion in epithelial tumors-is associated with tumor progression. To better understand the mechanisms that maintain carcinoma cells in a differentiated state, we have dissected in vitro differentiation pathways in the mucus-secretor HT-29 M6 colon cancer cell line, which spontaneously differentiates in postconfluent cultures. By lowering the extracellular calcium concentration to levels that prevent intercellular adhesion and epithelial polarization, our results reveal that differentiation is calcium-dependent and involves: (i) a process of cell cycle exit to G(0) and (ii) the induction of a transcriptional program of differentiation gene expression (i.e., mucins MUC1 and MUC5AC, and the apical membrane peptidase DPPIV). In calcium-deprived, non-differentiated postconfluent cultures, differentiation gene promoters are repressed by a trichostatin A (TSA)-sensitive mechanism, indicating that loss of gene expression by dedifferentiation is driven by histone deacetylases (HDAC). Since TSA treatment or extracellular calcium restoration allow gene promoter activation to similar levels, we suggest that induction of differentiation is one mechanism of HDAC inhibitor antitumor action. Moreover, transcriptional de-repression can also be induced in non-differentiating culture conditions by overexpressing the cyclin-dependent kinase inhibitor p27(KIP1), which is normally induced during spontaneous differentiation. Since p27(KIP1) downregulation in colon cancer is associated with poor prognosis independently of tumor cell division rates, we propose that p27 (KIP1) may prevent tumor progression by, at least in part, enhancing the expression of some differentiation genes. Therefore, the HT-29 M6 model allows the identification of some basic mechanisms of cancer cell differentiation control, so far revealing HDAC and p27(KIP1) as key regulatory factors of differentiation gene expression.

The symbiotic biofilm of Sinorhizobium fredii SMH12, necessary for successful colonization and symbiosis of Glycine max cv Osumi, is regulated by Quorum Sensing systems and inducing flavonoids via NodD1.

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Francisco Pérez-Montaño

Full Text Available Bacterial surface components, especially exopolysaccharides, in combination with bacterial Quorum Sensing signals are crucial for the formation of biofilms in most species studied so far. Biofilm formation allows soil bacteria to colonize their surrounding habitat and survive common environmental stresses such as desiccation and nutrient limitation. This mode of life is often essential for survival in bacteria of the genera Mesorhizobium, Sinorhizobium, Bradyrhizobium, and Rhizobium. The role of biofilm formation in symbiosis has been investigated in detail for Sinorhizobium meliloti and Bradyrhizobium japonicum. However, for S. fredii this process has not been studied. In this work we have demonstrated that biofilm formation is crucial for an optimal root colonization and symbiosis between S. fredii SMH12 and Glycine max cv Osumi. In this bacterium, nod-gene inducing flavonoids and the NodD1 protein are required for the transition of the biofilm structure from monolayer to microcolony. Quorum Sensing systems are also required for the full development of both types of biofilms. In fact, both the nodD1 mutant and the lactonase strain (the lactonase enzyme prevents AHL accumulation are defective in soybean root colonization. The impairment of the lactonase strain in its colonization ability leads to a decrease in the symbiotic parameters. Interestingly, NodD1 together with flavonoids activates certain quorum sensing systems implicit in the development of the symbiotic biofilm. Thus, S. fredii SMH12 by means of a unique key molecule, the flavonoid, efficiently forms biofilm, colonizes the legume roots and activates the synthesis of Nod factors, required for successfully symbiosis.

Transfer of the pheromone-inducible plasmid pCF10 among Enterococcus faecalis microorganisms colonizing the intestine of mini-pigs

DEFF Research Database (Denmark)

Licht, Tine Rask; Laugesen, D.; Jensen, Lars Bogø

2002-01-01

A new animal model, the streptomycin-treated mini-pig, was developed in order to allow colonization of defined strains of Enterococcus faecalis in numbers sufficient to study plasmid transfer. Transfer of the pheromone-inducible pCF10 plasmid between streptomycin-resistant strains of E. faecalis OG...

Heme-Induced Biomarkers Associated with Red Meat Promotion of colon Cancer Are Not Modulated by the Intake of Nitrite

Science.gov (United States)

Chenni, Fatima Z; Taché, Sylviane; Naud, Nathalie; Guéraud, Françoise; Hobbs, Ditte A; Kunhle, Gunter G C; Pierre, Fabrice H; Corpet, Denis E

2013-01-01

Red and processed meat consumption is associated with the risk of colorectal cancer. Three hypotheses are proposed to explain this association, via heme/alcenal, heterocyclic amines or N-nitroso compounds. Rats have often been used to study these hypotheses, but the lack of enterosalivary cycle of nitrate in rats casts doubt on the relevance of this animal model to predict nitroso- and heme-associated human colon carcinogenesis. The present study was thus designed to clarify whether a nitrite intake that mimics the enterosalivary cycle can modulate heme-induced nitrosation and fat peroxidation. This study shows that, in contrast with the starting hypothesis, salivary nitrite did not change the effect of hemoglobin on biochemical markers linked to colon carcinogenesis, notably lipid peroxidation and cytotoxic activity in the colon of rat. However, ingested sodium nitrite increased fecal nitroso-compounds level, but their fecal concentration and their nature (iron-nitrosyl) would not be associated with an increased risk of cancer. The rat model could thus be relevant to study the effect of red meat on colon carcinogenesis in spite of the lack of nitrite recycling in rat’s saliva. PMID:23441609

Importance of neural mechanisms in colonic mucosal and muscular dysfunction in adult rats following neonatal colonic irritation.

Science.gov (United States)

Chaloner, A; Rao, A; Al-Chaer, E D; Greenwood-Van Meerveld, B

2010-02-01

Previous studies have shown that early life trauma induced by maternal separation or colonic irritation leads to hypersensitivity to colorectal distension in adulthood. We tested the hypothesis that repetitive colorectal distension in neonates leads to abnormalities in colonic permeability and smooth muscle function in the adult rat. In neonatal rats, repetitive colorectal distension was performed on days 8, 10, and 12. As adults, stool consistency was graded from 0 (formed stool) to 3 (liquid stool). Colonic tissue was isolated for histology and myeloperoxidase levels. The colonic mucosa was placed in modified Ussing chambers for measurements of permeability and short-circuit current responses to forskolin, electrical field stimulation, and carbachol. Segments of colonic musculature were placed in organ baths and contractile response to potassium chloride, electrical field stimulation, and carbachol were determined. In adult rats that experienced neonatal colonic irritation, no significant changes in colonic histology or myeloperoxidase activity were observed; however, stool consistency scores were increased. Mucosal permeability, measured as an increase in basal conductance, was significantly increased but no changes in short-circuit current responses were observed. In adulthood, rats that underwent colorectal distension as neonates exhibited an elevated smooth muscle contractile response to potassium chloride, but no changes in response to electrical field stimulation or carbachol. In summary, neonatal colonic irritation, shown previously to produce colonic hypersensitivity, leads to significant alterations in colonic mucosal and smooth muscle function characterized by loose stools, increased mucosal permeability, and increased smooth muscle contractility in the absence of colon inflammation in adulthood. Published by Elsevier Ltd.

Central neuropeptide Y receptors are involved in 3rd ventricular ghrelin induced alteration of colonic transit time in conscious fed rats

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Ritter Michael

2005-02-01

Full Text Available Abstract Background Feeding related peptides have been shown to be additionally involved in the central autonomic control of gastrointestinal functions. Recent studies have shown that ghrelin, a stomach-derived orexigenic peptide, is involved in the autonomic regulation of GI function besides feeding behavior. Pharmacological evidence indicates that ghrelin effects on food intake are mediated by neuropeptide Y in the central nervous system. Methods In the present study we examine the role of ghrelin in the central autonomic control of GI motility using intracerobroventricular and IP microinjections in a freely moving conscious rat model. Further the hypothesis that a functional relationship between NPY and ghrelin within the CNS exists was addressed. Results ICV injections of ghrelin (0.03 nmol, 0.3 nmol and 3.0 nmol/5 μl and saline controls decreased the colonic transit time up to 43%. IP injections of ghrelin (0.3 nmol – 3.0 nmol kg-1 BW and saline controls decreased colonic transit time dose related. Central administration of the NPY1 receptor antagonist, BIBP-3226, prior to centrally or peripherally administration of ghrelin antagonized the ghrelin induced stimulation of colonic transit. On the contrary ICV-pretreatment with the NPY2 receptor antagonist, BIIE-0246, failed to modulate the ghrelin induced stimulation of colonic motility. Conclusion The results suggest that ghrelin acts in the central nervous system to modulate gastrointestinal motor function utilizing NPY1 receptor dependent mechanisms.

Influence of the surgical manipulation of the colon in colonic induced carcinogenesis in rats Influencia de la manipulación quirúrgica del colon en la carcinogénesis cólica inducida en ratas

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J. F. Noguera Aguilar

2004-05-01

Full Text Available Aim: to investigate the influence of different experimental manipulations in a model of colonic experimental carcinogenesis with pharmacological induction in the rat. Experimental design: a total of 90 Sprague-Dawley male rats, divided into three groups, were used: non-surgical (n = 30; surgical with colonic trauma (n = 20, and surgical with colo-colonic anastomosis (n = 40. Carcinogenic induction was carried out with 1-2 dimethylhydrazine dihydrochloride. Colonic adenocarcinomas were identified and the number of tumors, as well as tumoral surface and percentage of tumoral surface was established. One-way ANOVA and Chi-square were employed for the statistical analysis. Results: the number of tumors was greater in the surgical group than in the control group, and tumors preferentially develop-ed around the manipulated colon. Surface and tumoral percentage were greater in the surgical group than in the control group, being also greater in the anastomosis group than in the group with colonic trauma. Within anastomosis groups, a greater tumor surface and percentage was found in the group with titanium than in the group with reabsorbable material. Conclusions: the experimental manipulation of the colon in rats enhances drug-induced colon carcingenesis. The creation of an anastomosis further increases the carcinogenic process compared with simulated anastomosis. This process is also enhanced by the quantity of suture material included in the anastomosis, and by the non-reabsorbable nature of the materials used in the anastomotic line.Objetivo: valorar la influencia de las distintas manipulaciones experimentales en un modelo de carcinogénesis cólica experimental con inducción farmacológica en la rata. Diseño experimental: se emplearon 90 ratas Sprague-Dawley macho, divididas en tres grupos: no quirúrgico (n=30; quirúrgico con traumatismo cólico (n=20, y quirúrgico con anastomosis colocólica (n=40. La inducción carcinogénica se realizó con

Anti-colitic effects of kanjangs (fermented soy sauce and sesame sauce) in dextran sulfate sodium-induced colitis in mice.

Science.gov (United States)

Song, Jia-Le; Choi, Jung-Ho; Seo, Jae-Hoon; Lim, Yaung-Iee; Park, Kun-Young

2014-09-01

This study was conducted to investigate the preventive effects of different kanjangs (Korean soy sauces), including acid-hydrolyzed soy sauce (AHSS), fermented soy sauce (FSS), and fermented sesame sauce (FSeS), on 2% dextran sulfate sodium (DSS)-induced ulcerative colitis in C57BL/6J mice. The fermented sauces, particularly FSeS, significantly suppressed DSS-induced body weight loss, increased colon length, and decreased colon weight/length ratios. Histological observations suggested that the fermented sauces prevented edema, mucosal damage, and the loss of crypts induced by DSS compared to the control mice and animals fed AHSS. FSeS and FSS decreased the serum levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-6, and IL-17α. mRNA expression of these cytokines as well as that of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in colon mucosa was also inhibited by the two sauces. Our results suggest that fermented sauces, especially FSeS, exert an anticolitic effect partially by reducing the serum levels of proinflammatory cytokines and inhibiting the mRNA expression of these factors in the colon tissue of mice treated with DSS. However, AHSS did not protect against DSS-induced colitis. In addition, low-dose treatment (4 mL/kg) with the fermented sauces resulted in greater anticolitic effects than consumption of a high quantity (8 mL/kg) of the sauces.

Meat and cancer: haemoglobin and haemin in a low-calcium diet promote colorectal carcinogenesis at the aberrant crypt stage in rats

Science.gov (United States)

Pierre, Fabrice; Taché, Sylviane; Petit, Claude R; Van Der Meer, Roelof; Corpet, Denis E

2003-01-01

High intake of red meat, but not of white meat, is associated with an increased risk of colon cancer. However, red meat does not promote cancer in rodents. Haemin, added to low-calcium diets, increases colonic proliferation, and haemoglobin, added to high-fat diets, increases the colon tumour incidence in rats, an effect possibly due to peroxyl radicals. We thus speculated that haem might be the promoting agent in meat, and that prevention strategies could use calcium and antioxidants. These hypotheses were tested in rats at the aberrant crypt foci (ACF) stage at 100 days. F344 rats (n=124) were given an injection of azoxymethane and were then randomised to 11 groups fed with low-calcium (20μmol/g) AIN76-based diets, containing 5% safflower oil. Haemin (0.25, 0.5 and 1.5μmol/g) or haemoglobin (1.5 and 3 μmol haem/g) was added to five experimental diets, compared to a control diet without haem. Three other high-haemin diets (1.5μmol/g) were supplemented with calcium (250μmol/g), antioxidant butylated hydroxyanisole and rutin (0.05% each), and olive oil, which replaced safflower oil. Faecal water was assayed for lipid peroxidation by thiobarbituric acid reactive substances (TBARs) test, and for cytolytic activity. Haemin strikingly increased the ACF size, dose-dependently, from 2.6 to 11.4 crypts/ACF (all p<0.001). The high-haemin diet also increased the number of ACF per colon (p<0.001). Promotion was associated with increased faecal water TBARs and cytotoxicity. Calcium, olive oil, and antioxidants each inhibited the haemin-induced ACF promotion, and normalised the faecal TBARs and cytotoxicity. The haemoglobin diets increased the number of ACF and faecal TBARs, but not the ACF size or the faecal cytotoxicity. In conclusion, dietary haemin is the most potent known ACF promoter. Haemoglobin is also a potent promoter of colorectal carcinogenesis. The results suggest that myoglobin in red meat could promote colon cancer. Diets high in calcium, or in oxidation

Colonic gas explosion during therapeutic colonoscopy with electrocautery

Science.gov (United States)

Ladas, Spiros D; Karamanolis, George; Ben-Soussan, Emmanuel

2007-01-01

Therapeutic colonoscopy with electrocautery is widely used around the world. Adequate colonic cleansing is considered a crucial factor for the safety of this procedure. Colonic gas explosion, although rare, is one of the most frightening iatrogenic complications during colonoscopy with electrocautery. This complication is the result of an accumulation of colonic gases to explosive concentrations, but may be prevented by meticulous bowel preparation. The purpose of this review is to discuss the indications and the types of bowel preparations for therapeutic colonoscopy, and to contribute recommendations for the adequate bowel preparation for colonoscopy with electrocautery. PMID:17879396

Persistent colonization of Helicobacter pylori in human gut induces gastroduodenal diseases

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Animesh Sarker

2014-12-01

Full Text Available Helicobacter pylori are gut bacteria colonize in the epithelial cell lining of the stomach and persist there for long du­ration. Around two-thirds of the world’s populations are infected with H. pylori and cause more than 90 percent of ulcers. The development of persistent inflammation is the main cause of chronic gastritis that finally results in a severe consequence known as stomach cancer. Two major virulence factors cytotoxin-associated gene product (cagA and the vacuolating toxin (vacA are mostly investigated as their close association with gastric carcinoma. In this review, host im­munity against H. pylori infection and their evasion mechanism are intensely explored. It is the fact, that understanding pin point molecular mechanisms of any infection is critical to develop novel strategies to prevent pertinent diseases. .J Microbiol Infect Dis 2014; 4(4: 170-176

Uridine prevents fenofibrate-induced fatty liver.

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Thuc T Le

Full Text Available Uridine, a pyrimidine nucleoside, can modulate liver lipid metabolism although its specific acting targets have not been identified. Using mice with fenofibrate-induced fatty liver as a model system, the effects of uridine on liver lipid metabolism are examined. At a daily dosage of 400 mg/kg, fenofibrate treatment causes reduction of liver NAD(+/NADH ratio, induces hyper-acetylation of peroxisomal bifunctional enzyme (ECHD and acyl-CoA oxidase 1 (ACOX1, and induces excessive accumulation of long chain fatty acids (LCFA and very long chain fatty acids (VLCFA. Uridine co-administration at a daily dosage of 400 mg/kg raises NAD(+/NADH ratio, inhibits fenofibrate-induced hyper-acetylation of ECHD, ACOX1, and reduces accumulation of LCFA and VLCFA. Our data indicates a therapeutic potential for uridine co-administration to prevent fenofibrate-induced fatty liver.

RNA interference prevents lipopolysaccharide-induced preprotachykinin gene expression

International Nuclear Information System (INIS)

Lai, Y.-L.; Yu, S.C.; Chen, M.-J.

2003-01-01

We showed previously that lipopolysaccharide (LPS) induces noncholinergic airway hyperreactivity to capsaicin via an upregulation of tachykinin synthesis. This study was designed to test whether double-stranded preprotachykinin (ds PPT) RNA, RNA interference (RNAi), prevents the LPS-induced alterations. First, cultured primary nodose ganglial cells of newborn Brown-Norway rats were divided into four groups: control; LPS; LPS+RNAi; and LPS+RNAi+liposome. Second, young Brown-Norway rats for the in vivo study were divided into three groups (control; LPS; and LPS+RNAi), and ds PPT RNA was microinjected bilaterally into the nodose ganglia in the LPS+RNAi group. Then, ganglial cells were collected from the culture whereas the nodose ganglia and lungs were sampled from the animals, and PPT mRNA and substance P (SP) levels were analyzed. Also, airway reactivity to capsaicin was performed in vivo. LPS induced significant increases in PPT mRNA and SP levels in vitro and in vivo and an increase in airway reactivity to capsaicin in vivo. However, ds PPT RNA, but not scrambled RNA, prevented all LPS-induced alterations. The effect of ds PPT RNA was not enhanced by liposome in vitro. Therefore, we demonstrated that the local application of RNAi prevents effectively the activation of the noncholinergic system modulating the lungs/airways

Importance of neural mechanisms in colonic mucosal and muscular dysfunction in adult rats following neonatal colonic irritation

OpenAIRE

Chaloner, A.; Rao, A.; Al-Chaer, E.D.; Meerveld, B. Greenwood-Van

2009-01-01

Previous studies have shown that early life trauma induced by maternal separation or colonic irritation leads to hypersensitivity to colorectal distension in adulthood. We tested the hypothesis that repetitive colorectal distension in neonates leads to abnormalities in colonic permeability and smooth muscle function in the adult rat. In neonatal rats, repetitive colorectal distension was performed on days 8, 10, and 12. As adults, stool consistency was graded from 0 (formed stool) to 3 (liqui...

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

Science.gov (United States)

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.

Carprofen-induced oxidative stress in mitochondria of the colonic mucosa of the dog.

Science.gov (United States)

Snow, Lynne A; McConnico, Rebecca S; Morgan, Timothy W; Hartmann, Erica; Davidson, Jacqueline R; Hosgood, Giselle

2014-07-01

The purpose of the study was to compare the conductance and mannitol permeability of canine colonic mucosa in response to carprofen or 2,4-dinitrophenol (DNP) with or without tempol pretreatment. Ten colonic mucosa sections per dog were mounted in Ussing chambers. Treatments were done in duplicate. Mucosa was exposed to carprofen (200 μg/mL) or DNP (0.25 mM), both with and without tempol (1 mM) pretreatment. Conductance was calculated every 15 min for 240 min. Mannitol flux was calculated over 3 consecutive 60-minute periods. Histology or electron microscopy was done after exposure. Conductance over time, mannitol flux, frequency of histologic categories, and electron microscopic changes were analyzed for treatment effects. The mean ± standard deviation (SD) conductance over time for carprofen or DNP-treated colons was not significantly different from control regardless of tempol pretreatment. Period 3 mannitol fluxes for carprofen and DNP-treated colon were not significantly different, but were greater than control. Period 3 mannitol flux for tempol + carprofen was significantly less than tempol + DNP-treated colon. Sloughing of cells and erosions were seen in the mucosa of carprofen-treated colon. Mitochondrial damage was seen more often in carprofen-treated than DNP-treated or control colon. Tempol pretreatment resulted in more ruptured mitochondria in the carprofen-treated colon; however, other mitochondrial changes were not significantly affected by tempol pretreatment in either carprofen or DNP treated colon. Treatment with carprofen or DNP increased the mannitol flux, but pretreatment with tempol mitigated the carprofen effect. It is apparent that structural mitochondrial damage occurs in the canine colonic mucosa after carprofen and DNP exposure.

Serotonin disturbs colon epithelial tolerance of commensal E. coli by increasing NOX2-derived superoxide.

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Banskota, Suhrid; Regmi, Sushil Chandra; Gautam, Jaya; Gurung, Pallavi; Lee, Yu-Jeong; Ku, Sae Kwang; Lee, Jin-Hyung; Lee, Jintae; Chang, Hyeun Wook; Park, Sang Joon; Kim, Jung-Ae

2017-05-01

Adherent-invasive E. coli colonization and Toll-like receptor (TLR) expression are increased in the gut of inflammatory bowel disease (IBD) patients. However, the underlying mechanism of such changes has not been determined. In the current study, it was examined whether gut serotonin (5-hydroxytryptamine, 5-HT) can induce adherent-invasive E. coli colonization and increase TLR expression. In a co-culture system, commensal E. coli strain (BW25113, BW) adhered minimally to colon epithelial cells, but this was significantly enhanced by 5-HT to the level of a pathogenic strain (EDL933). Without inducing bacterial virulence, such as, biofilm formation, 5-HT enhanced BW-induced signaling in colon epithelial cells, that is, NADPH oxidase (NOX)-dependent superoxide production, the up-regulations of IL-8, TLR2, TLR4, and ICAM-1, and the down-regulations of E-cadherin and claudin-2. In a manner commensurate with these gene modulations, BW induced an increase in NF-κB and a decrease in GATA reporter signals in colon epithelial cells. However, 5-HT-enhanced BW adhesion and colon epithelial responses were blocked by knock-down of NOX2, TLR2, or TLR4. In normal mice, 5-HT induced the invasion of BW into gut submucosa, and the observed molecular changes were similar to those observed in vitro, except for significant increases in TNFα and IL-1β, and resulted in death. In dextran sulfate sodium-induced colitis mice (an IBD disease model), in which colonic 5-HT levels were markedly elevated, BW administration induced death in along with large amount of BW invasion into colon submucosa, and time to death was negatively related to the amount of BW injected. Taken together, our results demonstrate that 5-HT induces the invasion of commensal E. coli into gut submucosa by amplifying commensal bacteria-induced epithelial signaling (superoxide production and the inductions of NOX2 and TLR2/TLR4). The authors suggest that these changes may constitute the molecular basis for the

Parenteral and Early Enteral Feeding in Patients with Colonic Tumor

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O. A. Malkov

2008-01-01

Full Text Available Objective: to provide evidence whether it is expedient to use an early enteral feeding protocol in patients with colonic malignancies in the postoperative period to prevent and to correct hemodynamic disorders, oxygen imbalance, and malnutrition. Subjects and methods. A hundred patients (61 males and 39 females aged 66.2±5.0 years, who had Stages 2—3 colonic malignancies, were examined. Two algorithms of postoperative management were analyzed using the traditional diet and early enteral feeding. Results. The early enteral feeding protocol improves central hemodynamics and oxygen and nutritional status, prevents moderate protein-energy deficiency in the early postoperative period and reduces the number of complications and fatal outcomes in patients with colonic malignancies. Key words: malignancies, malnutrition, hemo-dynamics, oxygen status, enteral feeding.

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

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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.

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

Preventing Noise-Induced Extinction in Discrete Population Models

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Irina Bashkirtseva

2017-01-01

Full Text Available A problem of the analysis and prevention of noise-induced extinction in nonlinear population models is considered. For the solution of this problem, we suggest a general approach based on the stochastic sensitivity analysis. To prevent the noise-induced extinction, we construct feedback regulators which provide a low stochastic sensitivity and keep the system close to the safe equilibrium regime. For the demonstration of this approach, we apply our mathematical technique to the conceptual but quite representative Ricker-type models. A variant of the Ricker model with delay is studied along with the classic widely used one-dimensional system.

Colon cancer: it's CIN or CIMP.

Science.gov (United States)

Issa, Jean-Pierre

2008-10-01

Combined genetic and epigenetic analysis of sporadic colon cancer suggest that it can no longer be viewed as a single disease. There are at least three different subsets with distinct clinico-pathologic features, with important implications for preventions, screening, and therapy.

Xanthohumol, a prenylated flavonoid contained in beer, prevents the induction of preneoplastic lesions and DNA damage in liver and colon induced by the heterocyclic aromatic amine amino-3-methyl-imidazo[4,5-f]quinoline (IQ)

International Nuclear Information System (INIS)

Ferk, Franziska; Huber, Wolfgang W.; Filipic, Metka; Bichler, Julia; Haslinger, Elisabeth; Misik, Miroslav; Nersesyan, Armen; Grasl-Kraupp, Bettina; Zegura, Bojana; Knasmueller, Siegfried

2010-01-01

Xanthohumol (XN) is a hop derived prenylated flavonoid contained in beer. Earlier findings indicated that it has promising chemopreventive properties and protects cells against DNA damage by carcinogens via inhibition of their activation. Furthermore, it was found that XN inhibits DNA synthesis and proliferation of cancer cells in vitro, inactivates oxygen radicals and induces apoptosis. Since evidence for its chemoprotective properties is restricted to results from in vitro experiments, we monitored the impact of XN on the formation of amino-3-methyl-imidazo[4,5-f]quinoline (IQ)-induced preneoplastic foci in livers and colons of rats (9/group). Additionally, we studied its effects on IQ-induced DNA damage in colonocytes and hepatocytes in single cell gel electrophoresis assays and on the activities of a panel of drug metabolising enzymes. Consumption of the drinking water supplemented with XN (71 μg/kg b.w.) before and during carcinogen treatment led to a significant reduction of the number of GST-p + foci in the liver by 50% and also to a decrease of the foci area by 44%. DNA migration was decreased significantly in both, colon mucosa and liver cells, but no alterations of the activities of different phases I and II enzymes were found in hepatic tissue. Our findings indicate that XN protects against DNA damage and cancer induced by the cooked food mutagen. Since the effects were observed with low doses of XN which are reached after consumption of brews with high XN levels, our findings may be relevant for humans.

Modulation of Mucosal Immune Response, Tolerance and Proliferation in Mice Colonized by the Mucin-Degrader Akkermansia muciniphila

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Muriel eDerrien

2011-08-01

Full Text Available Epithelial cells of the mammalian intestine are covered with a mucus layer that prevents direct contact with intestinal microbes but also constitutes a substrate for mucus-degrading bacteria. To study the effect of mucus degradation on the host-response, germ-free mice were colonized with Akkermansia muciniphila. This anaerobic bacterium belonging to the Verrucomicrobia is specialized in the degradation of mucin, the glycoprotein present in mucus, and found in high numbers in the intestinal tract of human and other mammalian species. Efficient colonization of A. muciniphila was observed with highest numbers in the cecum, where most mucin is produced. In contrast, following colonization by Lactobacillus plantarum, a facultative anaerobe belonging to the Firmicutes that ferments carbohydrates, similar cell-numbers were found at all intestinal sites. Whereas A. muciniphila was located closely associated with the intestinal cells, L. plantarum was exclusively found in the lumen. The global transcriptional host response was determined in intestinal biopsies and revealed a consistent, site-specific and unique modulation of about 750 genes in mice colonized by A. muciniphila and over 1500 genes after colonization by L. plantarum. Pathway reconstructions showed that colonization by A. muciniphila altered mucosal gene expression profiles towards increased expression of genes involved in immune responses and cell fate determination, while colonization by L. plantarum led to up-regulation of lipid metabolism. These indicate that the colonizers induce host responses that are specific per intestinal location. In conclusion, we propose that A. muciniphila modulates pathways involved in establishing homeostasis for basal metabolism and immune tolerance towards commensal microbiota.

Antibiotic consumption and Enterobacteriaceae skin colonization in hospitalized adults.

Science.gov (United States)

Kirby, A; Berry, C; West, R

2017-01-01

Enterobacteriaceae are increasingly antibiotic resistant, and skin colonization may contribute to their spread in hospitals. This study screened 100 hospitalized adults for Enterobacteriaceae skin colonization, and assessed potential risk factors, including antibiotic consumption. Multi-variable analysis found that antibiotic consumption whilst an inpatient [odds ratio (OR) 3.16, 95% confidence interval (CI) 1.19-8.4] and male sex (OR 2.92, 95% CI 1.06-8.4) were risk factors for Enterobacteriaceae skin colonization. If these risk factors are confirmed, work to understand the biological mechanism involved may lead to the development of interventions to prevent Enterobacteriaceae skin colonization. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Phage therapy reduces Campylobacter jejuni colonization in broilers

NARCIS (Netherlands)

Wagenaar, J.A.; Bergen, van M.A.P.; Mueller, M.A.; Wassenaar, T.M.; Carlton, R.M.

2005-01-01

The effect of phage therapy in the control of Campylobacter jejuni colonization in young broilers, either as a preventive or a therapeutic measure, was tested. A prevention group was infected with C. jejuni at day 4 of a 10-day phage treatment. A therapeutic group was phage treated for 6 days,

E Durans Strain M4-5 Isolated From Human Colonic Flora Attenuates Intestinal Inflammation

DEFF Research Database (Denmark)

Avram-Hananel, L.; Stock, J.; Parlesak, Alexandr

2010-01-01

to examine in vivo effects of prevention and therapy with E durans on clinical, biochemical, and histologic parameters of inflammation. RESULTS: In the coculture model, treatment with E durans and with butyrate reduced basal as well as E coli stimulated secretion of IL-8, IL-6, and TNF-α and increased...... inflammation, and inhibited colonic transcription of proinflammatory immune factors. The effect of therapeutic treatment alone on these parameters was more moderate but still significant. CONCLUSIONS: We conclude that E durans strain M4 to 5 and its metabolic product butyrate induce significant anti...

Programmed Cell Death, Proliferating Cell Nuclear Antigen and p53 Expression in Mouse Colon Mucosa during Diet-Induced Tumorigenesis

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Mauro Risio

2000-01-01

Full Text Available Western‐style diets (WDs trigger and sustain the early phases of tumorigenesis in mouse colon, and when continued throughout the life span lead to the development of dysplastic crypts. In order to evaluate the roles both of cell proliferation and programmed cell death (PCD in WD‐induced tumorigenesis, immunohistochemical detection of proliferating nuclear antigen (PCNA, in situ end labeling (TUNEL of DNA breaks, and p53 protein were carried out in mouse colonic mucosa during prolonged feeding of two WDs. PCNA Labeling Index of colonic crypts was significantly higher in WD‐treated animals than in controls only at the beginning of the nutritional study, the gap rapidly bridged by increased cell proliferation spontaneously occurring in the colonic mucosa during aging. A transient early homeostatic activation of PCD at the base of the crypt also was observed in WD groups. No changes in PCD were seen in the upper third of the crypt or in surface epithelium throughout the study, indicating that PCD in that colonic crypt segment produces a constant flux of cell loss, uninfluenced by homeostatic fluctuations. A major finding was an irreversible, progressive, age‐related decline of PCD at the crypt base in both control and treated animals that occurred during the second half of the rodents  life span. p53 protein was not immunohistochemically detected, suggesting that neither overexpression of wild‐type nor mutated forms of the protein are involved in the above mentioned changes.

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.

Transdermal deferoxamine prevents pressure-induced diabetic ulcers.

Science.gov (United States)

Duscher, Dominik; Neofytou, Evgenios; Wong, Victor W; Maan, Zeshaan N; Rennert, Robert C; Inayathullah, Mohammed; Januszyk, Michael; Rodrigues, Melanie; Malkovskiy, Andrey V; Whitmore, Arnetha J; Walmsley, Graham G; Galvez, Michael G; Whittam, Alexander J; Brownlee, Michael; Rajadas, Jayakumar; Gurtner, Geoffrey C

2015-01-06

There is a high mortality in patients with diabetes and severe pressure ulcers. For example, chronic pressure sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia inducible factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-induced and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a pressure-induced ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation.

Dietary pectin and calcium inhibit colonic proliferation in vivo by differing mechanisms.

Science.gov (United States)

Umar, S; Morris, A P; Kourouma, F; Sellin, J H

2003-12-01

Diet plays an important role in promoting and/or preventing colon cancer; however, the effects of specific nutrients remain uncertain because of the difficulties in correlating epidemiological and basic observations. Transmissible murine colonic hyperplasia (TMCH) induced by Citrobacter rodentium, causes significant hyperproliferation and hyperplasia in the mouse distal colon and increases the risk of subsequent neoplasia. We have recently shown that TMCH is associated with an increased abundance of cellular beta-catenin and its nuclear translocation coupled with up-regulation of its downstream targets, c-myc and cyclin D1. In this study, we examined the effects of two putatively protective nutrients, calcium and soluble fibre pectin, on molecular events linked to proliferation in the colonic epithelium during TMCH. Dietary intervention incorporating changes in calcium [high (1.0%) and low (0.1%)] and alterations in fibre content (6% pectin and fibre-free) were compared with the standard AIN-93 diet (0.5% calcium, 5% cellulose), followed by histomorphometry and immunochemical assessment of potential oncogenes. Dietary interventions did not alter the time course of Citrobacter infection. Both 1.0% calcium and 6% pectin diet inhibited increases in proliferation and crypt length typically seen in TMCH. Neither the low calcium nor fibre-free diets had significant effect. Pectin diet blocked increases in cellular beta-catenin, cyclin D1 and c-myc levels associated with TMCH by 70%, whereas neither high nor low calcium diet had significant effect on these molecules. Diets supplemented with either calcium or pectin therefore, exert anti-proliferative effects in mouse distal colon involving different molecular pathways. TMCH is thus a diet-sensitive model for examining the effect of specific nutrients on molecular characteristics of the pre-neoplastic colonic epithelium.

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.

Sodium bicarbonate-based hydration prevents contrast-induced nephropathy: a meta-analysis

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Tamhane Umesh

2009-05-01

Full Text Available Abstract Background Contrast-induced nephropathy is the leading cause of in-hospital acute renal failure. This side effect of contrast agents leads to increased morbidity, mortality, and health costs. Ensuring adequate hydration prior to contrast exposure is highly effective at preventing this complication, although the optimal hydration strategy to prevent contrast-induced nephropathy still remains an unresolved issue. Former meta-analyses and several recent studies have shown conflicting results regarding the protective effect of sodium bicarbonate. The objective of this study was to assess the effectiveness of normal saline versus sodium bicarbonate for prevention of contrast-induced nephropathy. Methods The study searched MEDLINE, EMBASE, Cochrane databases, International Pharmaceutical Abstracts database, ISI Web of Science (until 15 December 2008, and conference proceedings for randomized controlled trials that compared normal saline with sodium bicarbonate-based hydration regimen regarding contrast-induced nephropathy. Random-effects models were used to calculate summary odds ratios. Results A total of 17 trials including 2,633 subjects were pooled. Pre-procedural hydration with sodium bicarbonate was associated with a significant decrease in the rate of contrast-induced nephropathy (odds ratios 0.52; 95% confidence interval 0.34–0.80, P = 0.003. Number needed to treat to prevent one case of contrast-induced nephropathy was 16 (95% confidence interval 10–34. No significant differences in the rates of post-procedure hemodialysis (P = 0.20 or death (P = 0.53 was observed. Conclusion Sodium bicarbonate-based hydration was found to be superior to normal saline in prevention of contrast-induced nephropathy in this updated meta-analysis.