Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 316
Filtrar
1.
J Cancer Res Ther ; 20(1): 268-274, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554332

RESUMO

BACKGROUND: Aberrant crypt foci (ACF) are the earliest preneoplastic lesions in human colon, identifiable on chromoendoscopic screening. Our objective was to evaluate the %methylation of APC, CDKN2A, MLH1, RASSF1, MGMT, and WIF1 tumor suppressor genes (TSG) in ACF, corresponding colorectal carcinomas (CRC), and normal colonic mucosal controls. METHODS: In this study, macroscopically normal-appearing mucosal flaps were sampled 5-10 cm away from the tumor mass from 302 fresh colectomy specimens to identify ACF-like lesions. Thirty-five cases with multiple ACFs were selected (n 35) as the main study group, with corresponding sections from CRC (n 35) as disease controls, and mucosal tissue blocks from 20 colectomy specimens (normal controls), operated for non-neoplastic pathologies. Genomic DNA was extracted, and methylation-specific polymerase chain reaction (PCR) was performed on a customized methylation array model. %Methylation data were compared among the groups and with clinicopathological parameters. Selected target mRNA and protein expression studies were performed. RESULTS: %Methylation of TSGs in ACF was intermediate between normal colon and CRC, although a statistically significant difference was observed only for the WIF1 gene (P < 0.01). Also, there was increased nuclear ß-catenin expression and upregulation of CD44-positive cancer-stem cells in ACF and CRCs than in controls. Right-sided ACFs and dysplastic ACFs had a higher %methylation of CDKN2A (P < 0.01), whereas hyperplastic ACFs had a higher %methylation of RASSF1 (P 0.04). The topographic characteristics of ACFs did not correlate with TSG %methylation. CONCLUSIONS: Early epigenetic methylation of WIF1 gene is one of the mechanisms for ACF development in human colon.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Neoplasias Colorretais , Lesões Pré-Cancerosas , Humanos , Focos de Criptas Aberrantes/genética , Focos de Criptas Aberrantes/diagnóstico , Focos de Criptas Aberrantes/patologia , Neoplasias Colorretais/patologia , Colo/patologia , Hiperplasia/patologia , Metilação , Genes Supressores de Tumor , Lesões Pré-Cancerosas/patologia , Neoplasias do Colo/patologia , Mucosa Intestinal/patologia
2.
Asian Pac J Cancer Prev ; 25(2): 563-573, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415543

RESUMO

OBJECTIVE: The study's aim was to evaluate Brazilian Brown Propolis (BBP) and Artepillin C (ARC) chemopreventive action in Wistar rats' colons. METHODS: Fifty male Wistar rats were divided into ten experimental groups, including control groups, groups with and without 1,2-dimethylhydrazine (DMH) induction, and BBP, ARC, and ARC enriched fraction (EFR) treatments, for sixteen weeks. Aberrant crypt foci (ACF) were classified as hyperplastic or dysplastic, and proliferating cell nuclear antigen (PCNA) expression was quantified. RESULT: ACF amounts in experimental groups (induced or not) decreased in both colon portions, while the isolated Aberrant Crypt (AC) number increased. Experimental groups of animals showed higher hyperplasia and dysplasia amounts compared with control groups. The ACF dysplastic amount present in groups induced and treated, in both colon portions, had similar values to IDMH (DMH induction group without treatment). In addition, DMH was effective in ACF inducing and there was positive staining for PCNA in basal and upper dysplastic foci portions in all experimental groups, in the mitotic index (MI) evaluation. To conclude, considering all the experimental groups, the one treated with EFR (fraction enriched with ARC) had the lowest rates of cell proliferation. CONCLUSION: BBP and its derivatives prevented crypt cell clonal expansion.


Assuntos
Focos de Criptas Aberrantes , Antineoplásicos , Neoplasias do Colo , Fenilpropionatos , Própole , Ratos , Animais , Masculino , Ratos Wistar , Neoplasias do Colo/tratamento farmacológico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Própole/farmacologia , Própole/uso terapêutico , 1,2-Dimetilidrazina/toxicidade , Brasil , Focos de Criptas Aberrantes/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinógenos
3.
Sci Rep ; 14(1): 813, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191592

RESUMO

Mangiferin (MF) is a natural C-glucosylxantone compound that has many substantial curative potentials against numerous illnesses including cancers. The present study's goal is to appraise the chemo preventive possessions of MF on azoxymethane (AOM)-mediated colonic aberrant crypt foci (ACF) in rats. Rats clustered into 5 groups, negative control (A), inoculated subcutaneously with normal saline twice and nourished on 0.5% CMC; groups B-E injected twice with 15 mg/kg azoxymethane followed by ingestion of 0.5% CMC (B, cancer control); intraperitoneal inoculation of 35 mg/kg 5-fluorouracil (C, reference rats) or nourished on 30 mg/kg (D) and 60 mg/kg (E) of MF. Results of gross morphology of colorectal specimens showed significantly lower total colonic ACF incidence in MF-treated rats than that of cancer controls. The colon tissue examination of cancer control rats showed increased ACF availability with bizarrely elongated nuclei, stratified cells, and higher depletion of the submucosal glands compared to MF-treated rats. Mangiferin treatment caused increased regulation of pro-apoptotic (increased Bax) proteins and reduced the ß-catenin) proteins expression. Moreover, rats fed on MF had significantly higher glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and lower malondialdehyde (MDA) concentrations in their colonic tissue homogenates. Mangiferin supplementation significantly down-shifted pro-inflammatory cytokines (transforming growth factor-α and interleukine-6) and up-shifted anti-inflammatory cytokines (interleukine-10) based on serum analysis. The chemo-protective mechanistic of MF against AOM-induced ACF, shown by lower ACF values and colon tissue penetration, could be correlated with its positive modulation of apoptotic cascade, antioxidant enzymes, and inflammatory cytokines originating from AOM oxidative stress insults.


Assuntos
Focos de Criptas Aberrantes , Neoplasias Colorretais , Mangifera , Animais , Ratos , Antioxidantes/farmacologia , Citocinas , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/tratamento farmacológico , Azoximetano/toxicidade , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/tratamento farmacológico
4.
Int J Exp Pathol ; 104(6): 304-312, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37594023

RESUMO

Colorectal cancer, which is the third leading cause of cancer-related deaths worldwide, is a multistep disease, featuring preneoplastic aberrant crypt foci (ACF) as the early morphological manifestation. The roles of hemichannel-forming transmembrane Pannexin 1 (Panx1) protein have not been investigated in the context of colon carcinogenesis yet, although it has contrasting roles in other cancer types. Thus, this study was conducted to examine the effects of Panx1 knockout (Panx1-/- ) on the early events of chemically induced colon carcinogenesis in mouse. Wild type (WT) and Panx1-/- female C57BL6J mice were submitted to a chemically induced model of colon carcinogenesis by receiving six intraperitoneal administrations of 1,2-dimethylhydrazine (DMH) carcinogen. Animals were euthanized 8 h (week 7) or 30 weeks (week 37) after the last DMH administration in order to evaluate sub-acute colon toxicity outcomes or the burden of ACF, respectively. At week 7, Panx1 genetic ablation increased DMH-induced genotoxicity in peripheral blood cells, malondialdehyde levels in the colon, and apoptosis (cleaved caspase-3) in colonic crypts. Of note, at week 37, Panx1-/- animals showed an increase in aberrant crypts (AC), ACF mean number, and ACF multiplicity (AC per ACF) by 56%, 57% and 20%, respectively. In essence, our findings indicate that Panx1 genetic ablation promotes preneoplastic ACF development during chemically induced mouse colon carcinogenesis, and a protective role of Panx1 is postulated.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Lesões Pré-Cancerosas , Camundongos , Feminino , Animais , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/genética , 1,2-Dimetilidrazina/efeitos adversos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Colo , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/genética , Proteínas do Tecido Nervoso/efeitos adversos , Conexinas/genética , Conexinas/farmacologia
5.
Int J Mol Sci ; 24(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36982300

RESUMO

Colorectal cancer (CRC) is responsible for a notable rise in the overall mortality rate. Obesity is found to be one of the main factors behind CRC development. Andrographis paniculata is a herbaceous plant famous for its medicinal properties, particularly in Southeast Asia for its anti-cancer properties. This study examines the chemopreventive impact of A. paniculata ethanolic extract (APEE) against a high-fat diet and 1,2-dimethylhydrazine-induced colon cancer in Sprague Dawley rats. Sprague Dawley rats were administered 1,2-dimethylhydrazine (40 mg/kg, i.p. once a week for 10 weeks) and a high-fat diet (HFD) for 20 weeks to induce colorectal cancer. APEE was administered at 125 mg/kg, 250 mg/kg, and 500 mg/kg for 20 weeks. At the end of the experiment, blood serum and organs were collected. DMH/HFD-induced rats had abnormal crypts and more aberrant crypt foci (ACF). APEE at a dose of 500 mg/kg improved the dysplastic state of the colon tissue and caused a 32% reduction in the total ACF. HFD increased adipocyte cell size, while 500 mg/kg APEE reduced it. HFD and DMH/HFD rats had elevated serum insulin and leptin levels. Moreover, UHPLC-QTOF-MS analysis revealed that APEE was rich in anti-cancer phytochemicals. This finding suggests that APEE has anti-cancer potential against HFD/DMH-induced CRC and anti-adipogenic and anti-obesity properties.


Assuntos
Focos de Criptas Aberrantes , Anticarcinógenos , Neoplasias do Colo , Ratos , Animais , Ratos Sprague-Dawley , Andrographis paniculata , 1,2-Dimetilidrazina/toxicidade , Dieta Hiperlipídica/efeitos adversos , Extratos Vegetais/efeitos adversos , Neoplasias do Colo/prevenção & controle , Anticarcinógenos/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/etiologia , Carcinógenos
6.
Plant Foods Hum Nutr ; 78(2): 286-291, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36820999

RESUMO

Early intervention can significantly improve the colorectal cancer survival rate. Foods rich in phenolic compounds, such as jaboticaba (Myrciaria cauliflora), may prevent tumorigenesis. We investigated the effectivity of jaboticaba whole fruit ethanolic extract (FEX) in suppressing aberrant crypt foci (ACF), the earliest lesion of colorectal cancer (CRC), in 1,2-dimethylhydrazine (DMH)-induced rats and the underlying mechanisms related to the gut microbiota composition and short chain fatty acid (SCFA). This study was approved by the Institutional Animal Care and Use Committee (IACUC) of Providence University (Trial Registration Number 20180419A01, registration date: 22 December 2018). The FEX contains gallic acid and an especially high ellagic acid concentration of 54.41 ± 1.80 and 209.79 ± 2.49 mg/100 g FEX. The highest total ACF number (150.00 ± 43.86) was recorded in the DMH control (D) group. After 56 days of oral FEX treatment, the total ACF number in the low FEX dosage (DL) group was significantly lower compared to the D group (p < 0.05). The large-sized ACF (> 5 foci), which has a higher probability of progressing to later stage, was significantly decreased in the high FEX dosage (DH) group. The 16s rDNA metagenomic sequencing of the cecal material revealed that the CRC biomarker Lachnoclostridium was significantly suppressed in the DH group (p < 0.05), whereas some SCFA-producing taxa and the cecal butyrate concentration were significantly elevated in the DL and DH groups (p < 0.05). This study demonstrated the potential of jaboticaba whole fruit in CRC prevention, especially in the initial stage, by shifting gut microbiota composition and improving cecal butyrate level.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Neoplasias Colorretais , Ratos , Animais , Frutas , Ácido Gálico , Neoplasias Colorretais/prevenção & controle , Butiratos , 1,2-Dimetilidrazina/toxicidade
7.
Br J Nutr ; 129(3): 395-405, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35506448

RESUMO

Colorectal cancer is the third most diagnosed cancer worldwide and linked to dietary/lifestyle factors. Arthrospira (Spirulina) platensis (AP) contains bioactive compounds with beneficial effects in vivo/in vitro. We evaluated the effects of AP feeding against 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis. Male Sprague Dawley rats were given subcutaneous injections of DMH (4 × 40 mg/kg body weight) (G1-G3) or vehicle (G4-G5) twice a week (weeks 3-4). During weeks 1-4, animals were fed a diet containing 1 % (G2) or 2 % (G3-G4) AP powder (w/w). After this period, all groups received a balanced diet until week 12. Some animals were euthanised after the last DMH injection (week 4) for histological, immunohistochemical (Ki-67, γ-H2AX and caspase-3) and molecular analyses (real time-PCR for 91 genes), while other animals were euthanised at week 12 for preneoplastic aberrant crypt foci (ACF) analysis. Both AP treatments (G2-G3) significantly decreased the DMH-induced increase in γ-H2AX (DNA damage) and caspase 3 (DNA damage-induced cell death) in colonic crypts at week 4. In addition, Cyp2e1 (Drug metabolism), Notch1, Notch2 and Jag1 genes (Notch pathway) and Atm, Wee1, Chek2, Mgmt, Ogg1 and Xrcc6 genes (DNA repair) were also down-regulated by 2 % AP feeding (G3) at week 4. A significant reduction in ACF development was observed in both AP-treated groups (G2-G3) at week 12. In conclusion, findings indicate that AP feeding reduced acute colonic damage after DMH, resulting in fewer preneoplastic lesions. Our study provided mechanistic insights on dietary AP-preventive effects against early colon carcinogenesis.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Lesões Pré-Cancerosas , Spirulina , Ratos , Animais , Masculino , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/prevenção & controle , 1,2-Dimetilidrazina/toxicidade , Ratos Sprague-Dawley , Carcinogênese/patologia , Colo , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/prevenção & controle , Carcinógenos/toxicidade , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle
8.
Medicina (Kaunas) ; 58(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36556972

RESUMO

Background and Objectives: Aberrant crypt foci (ACF) are one of the earliest putative preneoplastic and, in some cases, neoplastic lesions in human colons. Many studies have confirmed the reduction of ACFs and colorectal adenomas after treatment with acetylsalicylic acid (ASA) commonly referred to as ASA; however, the minimum effective dose of ASA and the duration of use has not been fully elucidated. The objective of our study was to assess the significance of low dose ASA (75-mg internally once daily) to study the chemopreventive effect of ASA in ACF and adenomas development in patients taking this drug for a minimum period of 10 years. Materials and Methods: Colonoscopy, combined with rectal mucosa staining with 0.25% methylene blue, was performed on 131 patients. The number of rectal ACF in the colon was divided into three groups: ACF < 5; ACF 5−10; and ACF > 10. Patients were divided into two groups: the "With ASA" group (the study group subjects taking ASA 75-mg daily for 10 years); and "Without ASA" group (control group subjects not taking ASA chronically). The incidence of different types of rectal ACF and colorectal polyps in both groups of subjects was analysed and ascertained. Results: Normal ACF was found in 12.3% in the study group vs. 87.7% control group, hyperplastic 22.4% vs. 77.6%, dysplastic 25% vs. 75%, mixed 0% vs. 100%. Treatment with ASA affects the occurrence of colorectal adenomas. The amount of dysplastic ACFs was lower in the study group than in the control group. The increase in dysplastic ACFs decreases with age in both groups, with the increase greater in those not taking ASA. Conclusions: Patients who take persistent, chronic (>10 years) low doses of ASA have a lower total number of all types of rectal ACFs and adenomas compared to the control group.


Assuntos
Focos de Criptas Aberrantes , Adenoma , Neoplasias Colorretais , Humanos , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/epidemiologia , Focos de Criptas Aberrantes/patologia , Aspirina/uso terapêutico , Reto , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/tratamento farmacológico , Adenoma/prevenção & controle , Adenoma/patologia
9.
Cancer Prev Res (Phila) ; 15(10): 637-640, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36193659

RESUMO

The role of chronic inflammation and arachidonic acid (AA) metabolism in tumor progression has been well characterized for variety of cancers, with compelling data for colon cancer. Several preclinical and clinical studies primarily focused on inhibiting the cyclooxygenase pathways using NSAIDs and aspirin for colon cancer prevention. However, emerging evidence clearly supports the pro-tumorigenic role of 5-lipoxygenase and its downstream leukotriene pathway within AA metabolism. As discussed in the current issue, targeting the leukotriene pathway by cysteinyl leukotriene receptor antagonist (LTRA) montelukast suppressed formation of aberrant crypt foci (ACF) and cell proliferation in colonic epithelium, suggesting the potential of LTRAs for colon cancer prevention. Although this is a short clinical chemoprevention trial to explore the effects of LTRAs against ACF development, it is a significant and timely study opening avenues to further explore the possibilities of using LTRAs in other inflammation-associated precancerous lesions as well. In this spotlight commentary, we highlight the implications of their data and the opportunities for developing LTRAs as potential candidates for colorectal cancer interception. See related article by Higurashi et al., p. 661.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Focos de Criptas Aberrantes/patologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Araquidonato 5-Lipoxigenase/farmacologia , Ácido Araquidônico/metabolismo , Aspirina/farmacologia , Quimioprevenção , Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Neoplasias do Colo/prevenção & controle , Humanos , Inflamação/patologia , Antagonistas de Leucotrienos/farmacologia , Antagonistas de Leucotrienos/uso terapêutico , Leucotrienos/farmacologia , Prostaglandina-Endoperóxido Sintases/farmacologia
10.
Cancer Prev Res (Phila) ; 15(10): 661-668, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36083855

RESUMO

Leukotriene receptor antagonists (LTRA) are widely used drugs for treating allergic asthma, and they have recently been suggested to have a suppressive effect on carcinogenesis and cancer cell proliferation. Aberrant crypt foci (ACF) are considered a reliable surrogate biomarker of colorectal cancer. This prospective study explored the chemopreventive effect of an LTRA on colonic ACF formation and the safety of the medicine in patients as a pilot trial leading to a colorectal cancer chemoprevention trial.This was a nonrandomized, open-label, controlled trial in patients with colorectal ACFs. The participants were allocated to LTRA or observation groups. Patients in the LTRA group received 10 mg of montelukast orally daily for 8 weeks. After the intervention, colonoscopy was performed to evaluate the changes in the number of ACFs.From November 2017 to March 2020, 40 patients were enrolled. The first 30 were assigned to the LTRA group, and the remaining 10 were assigned to the observation group. In the LTRA group, the mean change in the number of ACFs per patient at 8 weeks from baseline was -2.4 ± 2.2, while the mean change in the observation group was 0.4 ± 2.3 (P = 0.002). There were no severe adverse events.This is the first study to explore the effect of LTRAs against colorectal ACF formation in humans. LTRAs are potential candidates for chemoprevention in colorectal cancer. PREVENTION RELEVANCE: We conducted the first LTRA chemoprevention trial for human rectal ACFs, which is considered a surrogate marker of colorectal carcinogenesis. 8-week treatment with LTRA suppressed ACF formation and cell proliferation in colonic epithelium. LTRAs are possible candidates for chemoprevention in colorectal cancer. See related Spotlight, p. 637.


Assuntos
Focos de Criptas Aberrantes , Neoplasias Colorretais , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/prevenção & controle , Carcinogênese , Quimioprevenção , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/prevenção & controle , Humanos , Antagonistas de Leucotrienos/uso terapêutico , Estudos Prospectivos
11.
Mol Nutr Food Res ; 66(20): e2200180, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35969485

RESUMO

SCOPE: Colon metabolomes associated with high-fat (H) versus energy-restricted (E) diets in early colorectal cancer (CRC) models have never been directly compared. The objectives of this study are to elucidate metabolites associated with diet, aberrant crypt foci (ACF), and diet:ACF interaction, using a lifetime murine model. METHODS AND RESULTS: Three-week-old mice consumed control (C), E, or H initiation diets for 18 weeks. ACF formation is initiated weeks 16-21 with azoxymethane injections, followed by progression diet crossover (to C, E, or H) through week 60. Colon extracts are analyzed using ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Metabolites associated with diet, ACF, or diet:ACF are determined using regression models (FDR-adjusted p-value <0.05). No metabolites are significantly associated with initiation diets, but concentrations of acylcarnitines and phospholipids are associated with C, E, and H progression diets. Purines, taurine, and phospholipids are associated with ACF presence. No significant associations between metabolites and diet:ACF interaction are observed. CONCLUSIONS: These results suggest that recent, rather than early-life, diet is more closely associated with the colon metabolome, particularly lipid metabolism. Results from this study also provide candidate biomarkers of early CRC development and provide support for the importance of early diet on influencing pre-CRC risk.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Lesões Pré-Cancerosas , Camundongos , Animais , Fosfolipídeos , Taurina , Camundongos Endogâmicos C57BL , Azoximetano/toxicidade , Colo , Ingestão de Energia , Dieta , Purinas , Carcinógenos
12.
J Oleo Sci ; 71(3): 419-423, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35153248

RESUMO

We have previously reported that dietary glucosylceramide (GlcCer) and rice extracts containing GlcCer reduce the formation of aberrant crypt foci (ACF) in the colons of 1,2-dimethylhydrazine (DMH)-treated mice, as a precursor model of colon cancer. This study investigated the impact of alkali-stable neutral lipids (NLs) containing free ceramides (Cer) and sterols on the formation of ACF in mice for the purpose of searching for functional components, irrespective of GlcCer, in rice extracts. The fraction was prepared from sake lees as a rice fermentation byproduct. Dietary NLs suppressed the marked increase in colon ACF treated with DMH.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/prevenção & controle , Álcalis , Animais , Colo , Glucosilceramidas , Camundongos
13.
Bol. latinoam. Caribe plantas med. aromát ; 21(1): 66-80, ene. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1372378

RESUMO

Melastoma malabathricum (M. malabathricum) extracts have been reported to exert various pharmacological activities including antioxidants, anti-inflammatory and antiproliferative activities. The objective of the present study was to determine the anticarcinogenic activity of its methanol extract (MEMM) against the azoxymethane (AOM)-induced early colon carcinogenesis in rats. Rats were randomly assigned to five groups (n=6) namely normal control, negative control, and treatment (50, 250 or 500 mg/kg of MEMM) groups. Colon tissues were harvested for histopathological analysis and endogenous antioxidant system determination. MEMM was also subjected to HPLC analysis. Findings showed that MEMM significantly (p<0.05) reversed the AOM-induced carcinogenicity by: i) reducing the formation of aberrant crypt foci (ACF) in colon tissues, and; ii) enhancing the endogenous antioxidant activity (catalase, superoxide dismutase and glutathione peroxidase). Moreover, various phenolics has been identified in MEMM. In conclusion, MEMM exerts the in vivo anticarcinogenic activity via the activation of endogenous antioxidant system and synergistic action of phenolics.


Se ha informado que los extractos de Melastoma malabathricum (M. malabathricum) ejercen diversas actividades farmacológicas, incluidas actividades antioxidantes, antiinflamatorias y antiproliferativas. El objetivo del presente estudio fue determinar la actividad anticancerígena de su extracto de metanol (MEMM) contra la carcinogénesis de colon temprana inducida por azoximetano (AOM) en ratas. Las ratas se asignaron al azar a cinco grupos (n=6), a saber, los grupos de control normal, control negativo y tratamiento (50, 250 o 500 mg/kg de MEMM). Tejidos de colon fueron recolectados para análisis histopatológico y determinación del sistema antioxidante endógeno. MEMM también se sometió a análisis de HPLC. Los hallazgos mostraron que MEMM invirtió significativamente (p<0.05) la carcinogenicidad inducida por AOM al: i) reducir la formación de focos de criptas aberrantes (ACF) en los tejidos del colon, y; ii) potenciar la actividad antioxidante endógena (catalasa, superóxido dismutasa y glutatión peroxidasa). Además, se han identificado varios fenólicos en MEMM. En conclusión, MEMM ejerce la actividad anticancerígena in vivo mediante la activación del sistema antioxidante endógeno y la acción sinérgica de los fenólicos.


Assuntos
Animais , Ratos , Extratos Vegetais/administração & dosagem , Anticarcinógenos/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Melastomataceae/química , Tamanho do Órgão/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ratos Sprague-Dawley , Colo/patologia , Folhas de Planta , Metanol , Compostos Fenólicos , Focos de Criptas Aberrantes , Carcinogênese/efeitos dos fármacos , Antioxidantes
14.
J Crohns Colitis ; 16(1): 98-108, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34232295

RESUMO

BACKGROUND AND AIMS: Several different types of non-conventional dysplasia have been recently described in inflammatory bowel disease [IBD]. Hypermucinous, goblet cell-deficient and crypt cell dysplasias have received most attention, but there is limited information regarding their clinicopathological features and clinical outcomes. METHODS: A total of 126 cases of hypermucinous [n = 55], goblet cell-deficient [n = 26] and crypt cell [n = 45] dysplasias from 97 IBD patients were collected from seven different institutions and analysed. RESULTS: The cohort included 62 [64%] men and 35 [36%] women with a mean age of 49 years [range: 20-78]. The majority of affected patients had longstanding IBD [mean duration: 18 years]. Nineteen [20%] patients had a concurrent history of primary sclerosing cholangitis. As a group, non-conventional dysplasia was predominantly found in patients with ulcerative colitis [UC] [n = 68; 70%] and occurred in the left colon [n = 80; 63%]; however, hypermucinous dysplasia [57%] was the least frequently associated with UC compared with goblet cell-deficient [74%] and crypt cell [89%] dysplasias [p = 0.016]. Fifty [52%] patients had a history of conventional dysplasia, detected in the same colonic segment as non-conventional dysplasia at a rate of 33%. Goblet cell-deficient dysplasia [74%] was more frequently associated with conventional dysplasia than hypermucinous [43%] and crypt cell [48%] dysplasias [p = 0.044]. While hypermucinous dysplasia often had a polypoid appearance [58%], crypt cell [96%] and goblet cell-deficient [65%] dysplasias were more likely to present as flat/invisible lesions [p < 0.001]. Most lesions were low-grade [87%] at diagnosis, but goblet cell-deficient dysplasia [31%] more often showed high-grade dysplasia [HGD] compared with hypermucinous [15%] and crypt cell [0%] dysplasias [p = 0.003]. Hypermucinous dysplasia usually demonstrated a tubulovillous/villous architecture [76%], whereas goblet cell-deficient dysplasia was predominantly tubular [92%]. A flat architecture was exclusively associated with crypt cell dysplasia [100%] [p < 0.001]. Immunohistochemical stain results for p53 were available for 33 lesions; 14 [42%] showed strong [3+] and patchy [10-50%] to diffuse [>50%] nuclear overexpression or null staining pattern, including four [33%] of 12 hypermucinous, two [29%] of seven goblet cell-deficient and eight [57%] of 14 crypt cell dysplastic lesions [p = 0.726]. Follow-up biopsies or resections were available for 92 low-grade lesions from 71 patients; 55 [60%] lesions, including 19 [49%] of 39 hypermucinous, 10 [59%] of 17 goblet cell-deficient and 26 [72%] of 36 crypt cell dysplastic lesions [p = 0.116], were associated with subsequent detection of HGD [n = 34; 37%] or adenocarcinoma [n = 21; 23%] at the site of previous biopsy or in the same colonic segment within a mean follow-up time of 12 months [range: <1-73]. CONCLUSIONS: Hypermucinous, goblet cell-deficient and crypt cell dysplasias have distinct clinicopathological features but appear to have a similar high risk of association with advanced neoplasia [HGD or adenocarcinoma]. More than half of the lesions [66%] presented as flat/invisible dysplasia, suggesting that IBD patients may benefit from random biopsy sampling in addition to targeted biopsies. Although not uncommonly associated with conventional dysplasia, non-conventional dysplasia may be the only dysplastic subtype identified in IBD patients. Therefore, it is important to recognize these non-conventional subtypes and recommend complete removal and/or careful examination and follow-up.


Assuntos
Focos de Criptas Aberrantes/patologia , Neoplasias Colorretais/patologia , Células Caliciformes/patologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Adulto , Idoso , Feminino , Humanos , Hiperplasia/patologia , Masculino , Pessoa de Meia-Idade
15.
J Ethnopharmacol ; 282: 114597, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34492318

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cuscuta reflexa Roxb. (C. reflexa) is a well-known traditional herbal plant, with numerous inherent therapeutic potentials including anticancer, antitumor, antibacterial, analgesic, anthelmintic, laxative and others. Moreover, the anticancer and antitumor potentials of this herb are ongoing with several trails, thus an attempt was made to assess the anticancer and hepatoprotective potentials of traditional C. reflexa herbs. METHOD: The dried ethanolic extract of C. reflexa was tested for acute oral toxicity in the treated animals subsequently their behavioral, neurological, and autonomic profiles changes were observed. The preliminary anti-cancer effects of extracts against 1, 2- Dimethyl hydrazine (DMH) induced animals were assessed through barium enema X-ray, colonoscopy, and Aberrant crypt foci (ACF) studies. The blood samples of the animals (treated and untreated) were collected and their in-vitro histological parameters were evaluated by the experienced technician. RESULTS: It was observed that C. reflexa significantly reduced Disease activity indexing (DAI) level and ACF counting, as well as demonstrated similar activity as of the standard drug 5-Fluorouracil (5-FU). Histopathological results revealed that the apoptotic bodies decreased in the DMH-induced group (group II) during cancer progression while in 5-FU treated (group III) and C. reflexa treated (group IV and V) animals the apoptotic bodies were increased. Inversely, the mitotic bodies increased in group II animals and reduced in group III, IV, and V animals. In the colonic section, DMH-induced cancer assay exhibited significant effects on the levels of hemoglobin, Packed cell volume (PCV), Red blood cell (RBC) counts, Mean corpuscular hemoglobin concentration (MCHC), Mean corpuscular volume (MCV), and Mean cell hemoglobin (MCH), and was found to be less in group II animals whereas administration of C. reflexa efficiently recovered back the loss probably by healing the colon damage/depletion of cancer progression. Moreover, compared to the group II animals, the neutrophil count was within the normal range in C. reflexa administered group. CONCLUSIONS: In the present study, the major hematological parameters significantly increased within DMH treated animals and exhibited extensive damage in the hepatic regions. Moreover, the histopathological findings demonstrated that the C. reflexa extracts potentially reduced the cell proliferation, with no toxicity. The C. reflexa extracts exhibited impending anti-cancer activity as well as protected the hepatic cells and thus could be potentially used in the management of colon or colorectal cancer and hepatic impairments.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Cuscuta , Testes de Toxicidade/métodos , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/patologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Comportamento Animal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colo/diagnóstico por imagem , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Monitoramento de Medicamentos/métodos , Medicamentos de Ervas Chinesas/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Camundongos , Extratos Vegetais/farmacologia
16.
Chem Biol Interact ; 350: 109686, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34627785

RESUMO

Colorectal cancer (CRC) is the third leading type of adult cancer in both genders with high morbidity and mortality worldwide. Even though the discovery of many antineoplastic drugs for CRC, the current therapy is not adequately efficient.This study was designed to investigate the effect and mechanism of Piclamilast (PIC), a selective PDE4 inhibitor, on a DMH-induced colorectal cancer (CRC) rat model. The rats were grouped (n = 10) into group 1 (control), group 2 (PIC 3 mg/kg, p.o.), groups 3-5 received DMH (20 mg/kg/week, S.C.), and groups 4 and 5 received PIC (1 and 3 mg/kg/day, p.o.) for 15 weeks. The DMH treatment increased aberrant crypt foci (ACF), Proliferating cell nuclear antigen (PCNA), and TBARS levels, along with decreased antioxidant defenses (GSH, GSH-Px, and catalase). Increased NF-κß expression and inflammatory cytokines were also evident. PIC dose-dependently reduced ACF and restored oxidative stress and inflammatory markers favorably. Moreover, PIC in its large, tested dose only significantly increased the intracellular level of cAMP and suppressed the activation of Ras and PI3K and its downstream Akt/mTOR signaling. Furthermore, PIC promoted CRC apoptosis, and increased the gene expression of the apoptotic factors, caspase-3 and Bax, and decreased the anti-apoptotic factor Bcl-2. The results of this study show that PIC may be a promising therapeutic agent for the treatment of CRC. PIC might inhibit the proliferation of CRC cells and induce apoptosis via multiple mechanisms that involve its antioxidant effect and inhibition of NF-κß and Ras/PI3K/Akt/mTOR signaling.


Assuntos
1,2-Dimetilidrazina/antagonistas & inibidores , 1,2-Dimetilidrazina/toxicidade , Benzamidas/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Inibidores da Fosfodiesterase 4/farmacologia , Piridinas/farmacologia , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/metabolismo , Focos de Criptas Aberrantes/patologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Modelos Animais de Doenças , Masculino , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Proteínas ras/metabolismo
17.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638991

RESUMO

Selenoproteins play important roles in many cellular functions and biochemical pathways in mammals. Our previous study showed that the deficiency of the 15 kDa selenoprotein (Selenof) significantly reduced the formation of aberrant crypt foci (ACF) in a mouse model of azoxymethane (AOM)-induced colon carcinogenesis. The objective of this study was to examine the effects of Selenof on inflammatory tumorigenesis, and whether dietary selenium modified these effects. For 20 weeks post-weaning, Selenof-knockout (KO) mice and littermate controls were fed diets that were either deficient, adequate or high in sodium selenite. Colon tumors were induced with AOM and dextran sulfate sodium. Surprisingly, KO mice had drastically fewer ACF but developed a similar number of tumors as their littermate controls. Expression of genes important in inflammatory colorectal cancer and those relevant to epithelial barrier function was assessed, in addition to structural differences via tissue histology. Our findings point to Selenof's potential role in intestinal barrier integrity and structural changes in glandular and mucin-producing goblet cells in the mucosa and submucosa, which may determine the type of tumor developing.


Assuntos
Focos de Criptas Aberrantes/dietoterapia , Focos de Criptas Aberrantes/metabolismo , Carcinogênese/efeitos dos fármacos , Neoplasias do Colo/sangue , Neoplasias do Colo/dietoterapia , Mucosa Intestinal/metabolismo , Selenoproteínas/metabolismo , Selenito de Sódio/administração & dosagem , Oligoelementos/administração & dosagem , Focos de Criptas Aberrantes/genética , Animais , Azoximetano/efeitos adversos , Carcinogênese/genética , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Citocinas/sangue , Sulfato de Dextrana/efeitos adversos , Dieta/métodos , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Selenoproteínas/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
18.
Nutrients ; 13(8)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34444868

RESUMO

BACKGROUND: Colorectal cancer is a highly prevalent disease, requiring effective strategies for prevention and treatment. The present research aimed to formulate a natural fiber-rich food product (NFRFP) and to evaluate its safety, toxicogenetics, and effects on aberrant crypt foci induced by 1,2-dimethyl-hydrazine in a preclinical model. METHODS: A total of 78 male Wistar rats were distributed in six experimental groups: negative control, positive control (1,2-Dimethylhydrazine-40 mg/Kg), and four groups fed with 10% NFRFP: NFRFP, pre-treatment protocol, simultaneous treatment, and post-treatment protocol. RESULTS: The NFRFP was shown to be a good source of fibers and did not change biometric, biochemical, hematological, and inflammatory parameters, and did not induce signs of toxicity and genotoxicity/carcinogenicity. NFRFP exhibited a chemopreventive effect, in all protocols, with damage reduction (% DR) of 75% in the comet test. NFRFP reduced the incidence of aberrant crypt outbreaks by 49.36% in the post-treatment protocol. CONCLUSIONS: The results suggest the applicability of NFRFP in the human diet due to potential production at an industrial scale and easy technological application in different products, since it could be incorporated in food without altering or causing small changes in final product sensory characteristics.


Assuntos
Focos de Criptas Aberrantes/prevenção & controle , Colo/patologia , Neoplasias Colorretais/prevenção & controle , Fibras na Dieta/administração & dosagem , 1,2-Dimetilidrazina , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/metabolismo , Focos de Criptas Aberrantes/patologia , Ração Animal , Animais , Colo/metabolismo , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Citocinas/sangue , Modelos Animais de Doenças , Mediadores da Inflamação/sangue , Masculino , Ratos Wistar
19.
Nutrients ; 13(6)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063915

RESUMO

The present report was designed to determine the antioxidant and antigenotoxic effects of phaseolin (isolated from Phaseolus vulgaris) against mouse colon and liver damage induced by azoxymethane (AOM) and its colon chemopreventive effect. Eight groups with 12 mice each were utilized for an eight-week experiment: the control group was intragastrically (ig) administered 0.9% saline solution; the positive control group was intraperitoneally (ip) injected with 7.5 mg/kg AOM twice a week (weeks three and four of the experiment); three groups were ig administered each day with phaseolin (40, 200, and 400 mg/kg); and three groups were ig administered phaseolin daily (40, 200, and 400 mg/kg) plus 7.5 mg/kg AOM twice a week in weeks three and four of the experiment. The results showed that phaseolin did not produce oxidative stress, DNA damage, or aberrant crypts; in contrast, 100% inhibition of lipoperoxidation, protein oxidation, and nitrites induction generated by AOM was found in both organs, and DPPH radical capture occurred. The two highest phaseolin doses reduced DNA damage induced by AOM in both organs by more than 90% and reduced the AOM-induced aberrant crypts by 84%. Therefore, our study demonstrated the strong in vivo antioxidant, antigenotoxic, and chemopreventive potential of phaseolin.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Colite/prevenção & controle , Phaseolus/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Focos de Criptas Aberrantes/prevenção & controle , Animais , Antioxidantes , Azoximetano , Quimioprevenção , Colite/induzido quimicamente , Colo , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Camundongos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sementes/química
20.
Cancer Prev Res (Phila) ; 14(5): 573-580, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33648940

RESUMO

Polyphenon E (Poly E) is a green tea polyphenol preparation whose most active component is epigallocatechin gallate (EGCG). We studied the cancer preventive efficacy and safety of Poly E in subjects with rectal aberrant crypt foci (ACF), which represent putative precursors of colorectal cancers. Eligible subjects had prior colorectal advanced adenomas or cancers, and had ≥5 rectal ACF at a preregistration chromoendoscopy. Subjects (N = 39) were randomized to 6 months of oral Poly E (780 mg EGCG) daily or placebo. Baseline characteristics were similar by treatment arm (all P >0.41); 32 of 39 (82%) subjects completed 6 months of treatment. The primary endpoint was percent reduction in rectal ACF at chromoendoscopy comparing before and after treatment. Among 32 subjects (15 Poly E, 17 placebo), percent change in rectal ACF number (baseline vs. 6 months) did not differ significantly between study arms (3.7% difference of means; P = 0.28); total ACF burden was also similar (-2.3% difference of means; P = 0.83). Adenoma recurrence rates at 6 months were similar by arm (P > 0.35). Total drug received did not differ significantly by study arm; 31 (79%) subjects received ≥70% of prescribed Poly E. Poly E was well tolerated and adverse events (AE) did not differ significantly by arm. One subject on placebo had two grade 3 AEs; one subject had grade 2 hepatic transaminase elevations attributed to treatment. In conclusion, Poly E for 6 months did not significantly reduce rectal ACF number relative to placebo. Poly E was well tolerated and without significant toxicity at the dose studied. PREVENTION RELEVANCE: We report a chemoprevention trial of polyphenon E in subjects at high risk of colorectal cancer. The results show that polyphenon E was well tolerated, but did not significantly reduce the number of rectal aberrant crypt foci, a surrogate endpoint biomarker of colorectal cancer.


Assuntos
Focos de Criptas Aberrantes/tratamento farmacológico , Catequina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Focos de Criptas Aberrantes/diagnóstico , Focos de Criptas Aberrantes/patologia , Idoso , Catequina/administração & dosagem , Catequina/efeitos adversos , Colo/diagnóstico por imagem , Colo/efeitos dos fármacos , Colo/patologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/patologia , Placebos/administração & dosagem , Placebos/efeitos adversos , Reto/diagnóstico por imagem , Reto/efeitos dos fármacos , Reto/patologia , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...