Reduction In Aberrant Crypt Foci Research Articles

The Extract of Perilla frutescens Seed Residue Attenuated the Progression of Aberrant Crypt Foci in Rat Colon by Reducing Inflammatory Processes and Altered Gut Microbiota.

Perilla frutescens (PF) seed residue is a waste from perilla oil production that still contains nutrients and phytochemicals. This study aimed to investigate the chemoprotective action of PF seed residue crude ethanolic extract (PCE) on the inflammatory-induced promotion stage of rat colon carcinogenesis and cell culture models. PCE 0.1 and 1 g/kg body weight were administered by oral gavage to rats after receiving dimethylhydrazine (DMH) with one week of dextran sulfate sodium (DSS) supplementation. PCE at high dose exhibited a reduction in aberrant crypt foci (ACF) number (66.46%) and decreased pro-inflammatory cytokines compared to the DMH + DSS group (p < 0.01). Additionally, PCE could either modulate the inflammation induced in murine macrophage cells by bacterial toxins or suppress the proliferation of cancer cell lines, which was induced by the inflammatory process. These results demonstrate that the active components in PF seed residue showed a preventive effect on the aberrant colonic epithelial cell progression by modulating inflammatory microenvironments from the infiltrated macrophage or inflammatory response of aberrant cells. Moreover, consumption of PCE could alter rat microbiota, which might be related to health benefits. However, the mechanisms of PCE on the microbiota, which are related to inflammation and inflammatory-induced colon cancer progression, need to be further investigated.

Hibiscus (Hibiscus sabdariffa L.) supplementation increases butyrate synthesis and reduces inflammatory cells, attenuating the formation of aberrant crypt foci in BALB/c mice induced to pre-neoplastic lesions.

The development of colorectal cancer involves some morphological changes, and in the initial stage, pre-neoplastic lesions called aberrant crypt foci (ACF) appear. Thus, an intervention with sources of bioactive compounds such as Hibiscus sabdariffa L., rich in phenolic compounds and anthocyanins, could attenuate the risk of developing these lesions due to its antioxidant, anti-inflammatory and anti-proliferative properties. Therefore, the aim of this study was to evaluate the effects of 5% and 10% supplementation of dehydrated H. sabdariffa calyces (DHSC) during the development of 1,2-dimethylhydrazine-induced preneoplastic lesions in male BALB/c mice. The characterization of DHSC was carried out. The in vivo experiment lasted 12 weeks, and the animals were randomly divided into 3 experimental groups: the control group (CON) and the supplemented groups with 5% DHSC and 10% DHSC. The activities of liver enzymes catalase and superoxide dismutase were determined. In addition, ACF, short chain fatty acids (SCFA), presence of inflammatory infiltrates, goblet cells and leukocytes in the colonic mucosa were quantified. There was a significant reduction in ACF and the presence of inflammatory infiltrates in the colon of animals in groups 5DHSC and 10DHSC. In addition, the 10DHSC group showed an increase in the activity of the catalse enzyme, in the production of butyrate and in the presence of NK cells in the colon, in addition to more hypertrophied goblet cells. Based on these findings, it is suggested that DHSC supplementation may be recommended to attenuate cellular responses in the early stage of preneoplastic lesions.

Reduction of Preneoplastic Lesions Induced by 1,2-Dimethylhydrazine in Rat Colon by Maslinic Acid, a Pentacyclic Triterpene from Olea europaea L.

Maslinic acid triggers compelling antiproliferative and pro-apoptotic effects in different human cancer cell lines. Hence, the chemopreventive activity was investigated on early stages of carcinogenesis induced by 1,2-dimethylhydrazine (DMH) which is a model that mimics human sporadic colorectal cancer. Male Sprague-Dawley rats were orally administered either maslinic acid at 5, 10 or 25 mg/kg dissolved in (2-hydroxypropyl)-β-cyclodextrin 20% (w/v) or the solvent for 49 days. After one week of treatment, animals received three weekly intraperitoneal injections of DMH at the dose of 20 mg/kg. Maslinic acid reduced the preneoplastic biomarkers, aberrant crypt foci (ACF) and mucin-depleted foci (MDF), already at 5 mg/kg in a 15% and 27%, respectively. The decline was significant at 25 mg/kg with decreases of 33% and 51%, respectively. Correlation analysis showed a significant association between the concentrations of maslinic acid found in the colon and the reduction of ACF (r = 0.999, p = 0.019) and MDF (r = 0.997, p = 0.049). The present findings demonstrate that maslinic acid induced an inhibition of the initiation stages of carcinogenesis. The assessment of this pentacyclic triterpene at the colon sheds light for designing diets with foods rich in maslinic acid to exert a chemopreventive activity in colorectal cancer.

470 - Randomized Placebo-Controlled Trial of Difluoromethylornithine (DFMO) Plus Aspirin for the Prevention of Colorectal Adenoma Recurrence and Reduction in Aberrant Crypt Foci (ACF) in Patients with Prior Advanced Adenomas or Cancer

470 - Randomized Placebo-Controlled Trial of Difluoromethylornithine (DFMO) Plus Aspirin for the Prevention of Colorectal Adenoma Recurrence and Reduction in Aberrant Crypt Foci (ACF) in Patients with Prior Advanced Adenomas or Cancer

Chemopreventive Potential of Select Herbal Teas and Spices on Azoxymethane-Induced Aberrant Crypt Foci in Fisher 344 Male Rats

Colon cancer is the third leading cause of death in the US. Selected herbal teas and spices may reduce incidence of chronic diseases, including cancer. The objective of this study was to identify the effect of strawberry leaf, raspberry leaf, hibiscus teas and cinnamon on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in Fisher 344 male rats. After acclimatization period (1 wk), 49 male weanling rats were divided into 16 groups. Control (CON) group fed AIN-93G diet; 15 treatment groups were administered control diet + strawberry leaf tea (STW), raspberry leaf tea (RAS), hibiscus tea (HIB), cinnamon (CIN), strawberry leaf tea + cinnamon (STW + CIN), raspberry leaf tea + cinnamon, (RAS + CIN), hibiscus tea + cinnamon (HIB + CIN), and strawberry leaf tea + raspberry leaf tea + hibiscus tea + cinnamon in combination (COM) at 2 levels each (teas added at 1% and 2%; CIN added at 2.5% and 5%). Rats received 24 mg/kg body weight AOM in saline s/c at 7 and 8 weeks of age. Animals received experimental diets until sacrificed by CO2 asphyxiation (17 weeks of age). ACF were enumerated in colons. Hepatic antioxidant enzymes were determined; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione (GH). Treatment groups had reduction in ACF compared to CON (154). Lowest ACF observed in HIB 2% + CIN 5% (13.16) with 91.45% reduction compared to CON. ACF observed in treatment groups administered teas and cinnamon combinations were lower than those administered teas singly. SOD and CAT activities in rats administered treatment diets were higher than CON (13.63 U/mL, 0.95 umol·min-l·ml-1). Rats administered COM (20.65 U/mL) had highest SOD activity. CAT activity was 51.27% higher in rats administered HIB 2% (1.96 umol·min-l·ml-1). GPX activity ranged from 7.26 (STW 1% + CIN 2.5%) to 9.59 (STW 2%) umol·min-l·ml-1. Results suggest that herbal teas and spices may reduce the risk of colon cancer and improve antioxidant status; regular consumption may provide beneficial health effects.

Abstract 4575: Açaí intake reduces the aberrant crypt foci development in a colitis-associated carcinogenesis model in male Wistar rats

Abstract Colorectal cancer is a main cause of cancer death in the western world. In Brazil, it is the third more common neoplasia in both men and women (INCA, 2014). In our previous study (Fragoso et al., Food Chem Toxicol., 2013), we showed that spray-dried açaí (Euterpe oleraceae Mart.) pulp intake retarded the development of colon cancer in male Wistar rats. Therefore, the objective of this research was to evaluate the potential protection of dietary freeze-dried açaí pulp using a chemically-induced colon carcinogenesis and colitis-associated model in male Wistar rats. The animals were randomly distributed into four groups: G1, DMH [dimethylhydrazine] + TNBS [2,4,6-trinitrobenzene sulfonic acid] + basal diet; G2, DMH + TNBS + basal diet with 5% açai pulp; G3, DMH + TNBS + basal diet with 7.5% açai pulp; G4, DMH + TNBS + basal diet with 0.2% of NAC [N-acetylcysteine]. The acute colitis was induced with the administration of 10 mg of TNBS dissolved in 0.25 ml 50% ethanol (v/v) by means of a Teflon cannula inserted 8 cm into the anus. At the end of the 25th week, animals were sacrificed for evaluation of Aberrant Crypt Foci (ACF) in the colon. Unsenctioned and fixed colons were analyzed for total aberrant crypt (AC) and total ACF and ACF multiplicity under methylene blue staining. The results were analyzed by ANOVA followed by post hoc Tukey test. A significant reduction in total ACF and AC for G2 when compared to G1 (p ≤0.001) was seen. Regarding the ACF multiplicity, it was observed a significant reduction in ACF with 4-10 aberrant crypts for G2 and G4 and for ACF with &amp;gt;10 aberrant crypts for G2-G4 groups in relation to the G1 group (p = ≤0.001, respectively). Also, it was observed a significant reduction in the number of total AC in the distal colon from the G2 and G4 groups compared to G1 group (p = 0.003) and in the medial colon from the G2 group compared to G1 group (p = 0.016). These results suggest that açaí intake may reduce the number of AC and ACF and the number of ACF with more than four aberrant crypts in this chemically-induced colon carcinogenesis and colitis-associated model in rats. Citation Format: MARIANA F. FRAGOSO, GUILHERME R. ROMUALDO, CLAUDIA H. PELLIZZON, LUIS F. BARBISAN. Açaí intake reduces the aberrant crypt foci development in a colitis-associated carcinogenesis model in male Wistar rats. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4575. doi:10.1158/1538-7445.AM2015-4575

Chemoprevention of Colon Cancer in a Rat Carcinogenesis Model Using a Novel Nanotechnology-Based Combined Treatment System

Colorectal cancer (CRC) is the third most common cause of cancer death in the United States, accounting for approximately 51,000 deaths each year. We have previously shown in vitro chemopreventive effects of mixtures of aspirin, folic acid, and calcium (AFAC) on colon cancer cell lines. The objective of the present study was to evaluate the in vivo effects of orally administered, colon targeted chemopreventive combination regimens on the inhibition of aberrant crypt foci (ACF) in a rat model of colon carcinogenesis using (i) unmodified (free drug) combinations of AFAC and (ii) nanoparticle-encapsulated combinations of the same agents. A 14-week animal study was conducted in three phases to determine an optimal effective dose from AFAC combinations and evaluate the efficacy of nanotechnology-based chemopreventive regimens administered in combined (mixtures) and individual (single entity) forms. ACF inhibition when compared with azoxymethane-treated rat control group was significant in both the unmodified and the modified nanoparticle-mediated chemopreventive regimens, showing a range of 31% to 38% (P < 0.05) and 50% to 75% (P < 0.001) reduction, respectively, in the number of ACFs. In addition, the nanoparticulate combination regimens of AFAC showed a 2-fold increase in suppression of ACF compared with free drug mixtures. Individual administration of nanoparticle-encapsulated drugs showed no significant effect on the reduction of ACF. Histochemical analysis provided further confirmation of chemopreventive effects, showing a significant reduction in cell nuclear proliferation. Overall, our results provide a strong proof of concept using nanoparticle-mediated combination treatment in the chemoprevention of colon cancer.

Inhibition of experimental colorectal cancer and reduction in renal and gastrointestinal toxicities by copper–indomethacin in rats

To evaluate, for the first time, the efficacy of copper-indomethacin in the inhibition of aberrant crypt foci formation using the azoxymethane-induced adenocarcinoma model, to examine cell viability in the HCT-116 colorectal cancer cell line, gastrointestinal permeability, mitochondrial oxidative damage, and renal toxicity in rat models. Azoxymethane-induced adenocarcinoma rats were dosed with indomethacin and copper-indomethacin for 28 days and aberrant crypt foci were evaluated. HCT-116 colorectal cancer cells were exposed to indomethacin and copper-indomethacin at 0-250 microg/mL (0-698 microM for indomethacin, and 0-147 microM for copper-indomethacin), and cell viability was measured. Acute gastrointestinal toxicity was measured using gastrointestinal permeability markers, gastrointestinal ulceration and bleeding, and measurement of an acute-phase protein haptoglobin. Effects of acute and chronic administration of indomethacin and copper-indomethacin on urinary electrolyte concentrations were examined. Both indomethacin and copper-indomethacin resulted in a significant reduction in aberrant crypt foci in azoxymethane-treated rats. In parallel, high concentrations of indomethacin and copper-indomethacin also reduced cell viability in HCT-116 colorectal cancer cells. However, copper-indomethacin was considerably safer in all measures of gastrointestinal toxicity compared to indomethacin. In addition, indomethacin reduced urinary electrolytes at an ulcerogenic dose of 10 mg/kg acutely and chronically at 3.0 mg/kg for 28 days, whereas copper-indomethacin at equimolar doses of indomethacin affected urine electrolytes after acute dosing but not after chronic dosing for 28 days. Copper-indomethacin has both gastrointestinal and renal sparing properties while maintaining efficacy in experimental adenocarcinoma.

Methionine Restriction Inhibits Colon Carcinogenesis

: Previously, we demonstrated that life-long methionine restriction (MR) in rats increases life span and inhibits aging-related disease processes. The present study examines the effects of MR on the formation of preneoplastic aberrant crypt foci (ACF) in the colon of azoxymethane (AOM)-treated rats. Six-week-old male F344 rats were placed on essential amino acid-defined diets containing either 0.86% Met (control diet) or 0.17% Met (MR diet) and 1 wk later were given AOM (15 mg/kg/wk, s.c.) for 2 consecutive wk. Ten weeks after the final AOM treatment, ACF formation was markedly reduced in rats fed the MR diet with ACF containing ≥ 4 crypts/focus being reduced by over 80% compared to controls (P < 0.001). A similar 83% reduction in ACF containing ≥ 4 crypts/focus was observed in rats fed the MR diet only during the post-initiation period (after the final dose of AOM; P < 0.001). Five weeks after AOM administration, a 12% reduction in colonic cell proliferation was observed in MR rats compared to controls (P < 0.05). These results show that MR inhibits colonic tumor development in the rat, an effect that occurs primarily during post-initiation phases of carcinogenesis and may be due, in part, to an inhibition of colonic cell proliferation.

Anticarcinogenic effect of phytic acid (IP 6): Apoptosis as a possible mechanism of action

Several in vivo and in vitro studies provide convincing evidence for the anticarcinogenic properties of phytic acid (PA) (Inositol hexaphosphate, IP 6). The objectives of this investigation were to elucidate the effects of PA on suppression of colonic aberrant crypt foci (ACF) and to study the inhibitory effect of IP 6 on human colon carcinoma, CaCo-2 cell line. Fisher 344 male, weanling rats were divided into 3 groups of 15 each and were fed control diet (AIN 93 G-C) and C+(1 or 2 g/100 g PA in water) for 13 weeks. Rats received 2 s.c. injections of azoxymethane (AOM) in saline at 16 mg/kg body weight at 7 and 8 weeks of age. There was a 36% and 42% reduction in ACF in 1 and 2 g/100 g PA groups compared to control group ( P < 0.001 ) . Cytotoxic effect of IP 6 was evaluated on Caco-2 cell line at concentrations of 0.25–4 g mol/l using lactate dehydrogenase (LDH) assay (LDH released from the cytosol of damaged cells into the supernatant), histone-associated DNA fragmentation assay using a cell death detection ELISA ® kit and microscopic analysis. The cells were treated with 0.25, 0.5, 1.0, 2.0, 4 g mol/l of IP 6 and incubated for 24 and 48 h. After 24 h of incubation, LDH release ranged from 13.55% to 44.70%. Histone-associated DNA fragmentation (an assay based on the quantitative sandwich-enzyme-immunoassay- principle directed against DNA and histones which allows the specific determination of mono- and oligonucleosomes in the cytoplasmic fraction of cell lysates) was also dose dependent. CaCo-2 cells grown on slide flaskets in the presence of 0.25 g mol/l IP 6 showed membrane blebbing (zeiosis) characteristic of apoptitic activity. Results of this study indicate that IP 6 might exert anticarcinogenic activity through induction of apoptosis.

Polyethylene glycol reduces inflammation and aberrant crypt foci in carcinogen-initiated rats

Polyethylene glycol 8000 inhibits the formation of tumors and of aberrant crypt foci (ACF) in carcinogen-initiated rats. We asked: is the inhibition associated with a reduction of colonic inflammation and an increase in colonic cell permeability? Twenty-eight, male F 344 rats were divided into two groups, 10 control animals and 18 animals initiated with azoxymethane. Nine of the rats in the carcinogen-initiated group were given a diet with 5% PEG 8000 in an AIN-93 based, high fat diet. The other nine, and the control group received the diet without the addition of PEG. Nine weeks later, the rats receiving the diet containing PEG had a 43% reduction in ACF ( P<0.001) compared with the carcinogen-initiated rats on the control diet, a result confirming earlier observations that PEG inhibits colon carcinogenesis. The animals receiving the diet containing PEG also had a 10-fold reduction in fecal granulocyte marker protein (GMP) ( P<0.001) compared with both the carcinogen-treated and the control animals. PEG reduced inflammation below the levels of carcinogen-treated and of untreated animals. Fecal water from the rats receiving PEG did not reduce transepithelial resistance of, or manitol flux through, human Caco-cells grown as monolayers in vitro. PEG may reduce colon carcinogenesis through a mechanism involving colonic inflammation.

Inhibition of Colonic Aberrant Crypt Foci by Curcuminin Rats Is Affected by Age

Curcumin has antioxidative, anti-inflammatory, and chemopreventive activities. To determine whether aging affects the inhibition of colon carcinogenesis by curcumin, young (6 wk), mature (12 mo), and old (22 mo) F344 male rats were fed either AIN-93 containing 0.6% curcumin or AIN-93 control diet. Aberrant crypt foci (ACF) were induced with two weekly s.c. injections of azoxymethane. After an additional 3 mo on the diets, the number, multiplicity, and distribution of ACF were evaluated. Addition of curcumin to the diet reduced the number of ACF by 49% in young rats and by 55% in old rats (P < 0.05). However, interestingly, no reduction of ACF was found in mature rats fed curcumin. Inhibition of large ACF was also affected by age, with the greatest reduction of large ACF occurring in old rats. However, animal age did not significantly alter the effect of dietary curcumin on reduction of cyclooxygenase-2 mRNA expression in the liver or reduction of serum total cholesterol levels. These results indicate that age may play a significant role in the efficacy of chemoprevention of colon cancer by curcumin.

Reduction of aberrant crypt foci by ingestion of polydextrose in the rat colorectum

To investigate the effect of dietary polydextrose on development of aberrant crypt foci (ACF), we fed rats with polydextrose-containing diet in various timing before or after 1,2-dimethylhydrazine (DMH) injection and measured ACF parameters. Every parameter for ACF was significantly reduced in the rats fed polydextrose from day 7 before DMH injection than in the fiber-free diet fed rats. This study shows that ingestion of polydextrose has protective effect on ACF especially in the rectum and the timing of dietary treatment is critical for inhibition of ACF development.

Prevention by retinoids of azoxymethane-induced tumors and aberrant crypt foci and their modulation of cell proliferation in the colon of rats.

Retinoids are proposed chemopreventive agents that inhibit cell proliferation and induce differentiation. Their ability to prevent azoxymethane (AOM)-induced aberrant crypt foci (ACF) and tumors and to modulate cell proliferation was investigated in the colon of male F344 rats. Thirteen retinoids were evaluated for prevention of ACF and two of them, 9-cis-retinoic acid (RA) and 4-(hydroxyphenyl)retinamide (4-HPR), were also evaluated for prevention of colon cancer. The retinoids were administered continuously in the diet starting 1 week prior to the first of two weekly 15 mg/kg i.p. injections of AOM and for a total of either 5 or 36 weeks in order to evaluate their effect on colonic ACF and tumors. At a concentration of 1 mmol/kg diet, 2-(carboxyphenyl)retinamide caused the greatest reduction (57.7%) in the yield of ACF. 9-cis-RA was toxic at 1 mmol/kg so that it was evaluated at 0.1 mmol/kg, resulting in a 41.6% reduction in ACF. The ability of the retinoids to reduce the proliferating cell nuclear antigen (PCNA) labeling index in ACF and in non-involved crypts correlated with their ability to prevent ACF. Both 9-cis-RA (0.1 and 0.2 mmol/kg diet) and 4-HPR (1 and 2 mmol/kg diet) were highly effective in decreasing the yield of AOM-induced colon tumors. In summary, retinoids were demonstrated to reduce cell proliferation and to prevent ACF and tumors in the colon, suggesting promise as preventive agents for colon cancer.

Reduction of aberrant crypt foci induced in rat colon with azoxymethane or methylnitrosourea by feeding cholic acid

Recent studies in our laboratory have demonstrated that feeding cholic acid (CHA) to rats treated with a single dose of azoxymethyane (AOM) reduces the growth of putative preneoplastic lesions, aberrant crypt foci (ACF), in a dose-dependent manner [1]. This finding was unexpected since CHA has been reported to promote colon cancer in rats receiving multiple treatments of the colon carcinogen, methylnitrosourea (MNU). The main objective of the present investigation was to evaluate the effect of the type of carcinogen and treatment protocol on the induction and growth of ACF in conjunction with CHA treatment. Male Sprague — Dawley rats received 0, 1 or 2 treatments with AOM or MNU and were fed either the AIN-76A or AIN-76A plus 0.2% CHA diet for 4 weeks. The total number and average size of ACF were significantly reduced in CHA-fed animals regardless of the type or number of treatments of carcinogen. The greatest reduction of ACF due to CHA-feeding was seen in the distal colon. The average crypt multiplicity (number of crypts in each ACF) was not altered by diet or carcinogen treatment. Colonic cell proliferation (crypt height and number of mitotic figures) was significantly increased in CHA-fed animals compared to control diet animals. Therefore, feeding CHA for 4 weeks reduced the number and size of ACF in rats induced by 1 or 2 injections of AOM or MNU, despite stimulation of colonic cell proliferation. These findings suggest further investigation is needed to understand the mechanism of promotion by cholic acid and the value of number and growth characteristics of ACF as a biological endpoint in the pathogenesis of colon cancer.