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1.
Pharmacol Res ; 159: 104809, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32502642

RESUMO

Microbiome therapy has attracted a keen interest from both research and business sectors. Our lab has been applying this "second genome" platform to assess the functionality of herbal medicines with fulfilling results. In this study, we applied this platform to assess the potential cancer-preventive effects of three selected adaptogenic plants. The flower buds from these plants were used to constitute Preparations SL and FSP according to the receipts of two commonly consumed Chinese medicinal decoctions for gastrointestinal discomfort. Preparation SL contains Sophorae japonica and Lonicerae Japonicae, and Preparation FSP contains Sophorae japonica and Gardenia Jasminoides. SL and FSP extracts significantly (p < 0.001) lowered the polyp burden, as well as the expressions of oncogenic signaling molecules, such as MAPK/ERK, PI3K/AKT, and STAT3 in ApcMin/+ mice. The inflamed gut was alleviated by shifting M1 to M2 macrophage phenotypes and the associated immune cytokines. The other remarkable change was on the extracellular tight junction protein complex, where the occludin, ZO-1, ICAM-1, E-cadherin were significantly (p < 0.05) upregulated while the N-cadherin and ß-catenin were downregulated in the treated mice. The above physiological changes in the gut epithelial barrier were companied with the changes in gut microbiome. The 16S Sequencing data revealed a marked decrease in the potential pathogens (especially Helicobacter species and hydrogen sulfide producing-bacteria) and the increase in beneficial bacteria (especially for species from the genera of Akkermansia, Barnesiella, Coprococcus, Lachnoclostridium, and Ruminococcus). The majority of which were the short-chain fatty acids (SCFAs) producers. Meanwhile SCFAs-sensing G protein-coupled receptors (GPCRs), including GPR41, GPR43, and GPR109a were also significantly upregulated. In a recent report, we proved that the bacteria-derived SCFAs plays an essential role to the anti-cancer effects of the mushroom polysaccharides and saponins in ApcMin/+ mice. In this study, we further demonstrated that butyrate treatment could enhance the extracellular tight junction protein complex as effective as the treatments with SL and FSP to the ApcMin/+ mice. Our findings provide strong evidence of the vital role of the SCFA-producers and their metabolites to the cancer-preventive properties of the SL and FSP preparations.


Assuntos
Anticarcinógenos/farmacologia , Bactérias/efeitos dos fármacos , Neoplasias Colorretais/prevenção & controle , Ácidos Graxos/metabolismo , Flores/química , Microbioma Gastrointestinal , Mucosa Intestinal/efeitos dos fármacos , Pólipos Intestinais/prevenção & controle , Magnoliopsida/química , Junções Íntimas/efeitos dos fármacos , Animais , Anticarcinógenos/isolamento & purificação , Bactérias/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Citocinas/metabolismo , Gardenia/química , Genes APC , Interações Hospedeiro-Patógeno , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Pólipos Intestinais/imunologia , Pólipos Intestinais/metabolismo , Pólipos Intestinais/microbiologia , Lonicera/química , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Sophora/química , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
2.
Sci Rep ; 9(1): 14783, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31616028

RESUMO

Inulin-rich foods exert a prebiotic effect, as this polysaccharide is able to enhance beneficial colon microbiota populations, giving rise to the in situ production of short-chain fatty acids (SCFAs) such as propionic and butyric acids. These SCFAs are potent preventive agents against colorectal cancer due to their histone deacetylases inhibitory properties, which induce apoptosis in tumor colonocytes. As colorectal cancer is the fourth most common neoplasia in Europe with 28.2 new cases per 100,000 inhabitants, a cost-effective preventive strategy has been tested in this work by redesigning common porcine meat products (chorizo sausages and cooked ham) consumed by a substantial proportion of the population towards potential colorectal cancer preventive functional foods. In order to test the preventive effect of these inulin-rich meat products against colorectal cancer, an animal model (Rattus norvegicus F344) was used, involving two doses of azoxymethane (10 mg/kg) and two treatments with dextran sodium sulfate (DSS) during a 20-week assay period. Control feed, control sausages, functional sausages (15.7% inulin), control cooked ham and functional cooked ham (10% inulin) were used to feed the corresponding animal cohorts. Then, the animals were sacrificed and their digestive tract tissues were analyzed. The results showed a statistically significant 49% reduction in the number of colon polyps in the functional meat products cohorts with respect to the control meat products animals, as well as an increase in the cecum weight (an indicator of a diet rich in prebiotic fiber), a 51.8% increase in colon propionate production, a 39.1% increase in colon butyrate concentrations, and a reduction in the number of hyperplastic Peyer's patches. Metagenomics studies also demonstrated colon microbiota differences, revealing a significant increase in Bacteroidetes populations in the functional meat products (mainly due to an increase in Bacteroidaceae and Prevotellaceae families, which include prominent propionate producers), together with a reduction in Firmicutes (especially due to lower Lachnospiraceae populations). However, functional meat products showed a remarkable increase in the anti-inflammatory and fiber-fermentative Blautia genus, which belongs to this Lachnospiraceae family. The functional meat products cohorts also presented a reduction in important pro-inflammatory bacterial populations, such as those of the genus Desulfovibrio and Bilophila. These results were corroborated in a genetic animal model of CRC (F344/NSlc-Apc1588/kyo) that produced similar results. Therefore, processed meat products can be redesigned towards functional prebiotic foods of interest as a cost-effective dietary strategy for preventing colorectal cancer in human populations.


Assuntos
Neoplasias Colorretais/prevenção & controle , Alimento Funcional , Pólipos Intestinais/prevenção & controle , Inulina/administração & dosagem , Produtos da Carne , Neoplasias Experimentais/prevenção & controle , Animais , Azoximetano/toxicidade , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Sulfato de Dextrana/toxicidade , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/biossíntese , Microbioma Gastrointestinal/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Pólipos Intestinais/induzido quimicamente , Pólipos Intestinais/genética , Pólipos Intestinais/microbiologia , Masculino , Metagenômica , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Experimentais/microbiologia , Prebióticos/administração & dosagem , Ratos , Suínos
3.
Sci Rep ; 8(1): 13974, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30228361

RESUMO

The human intestine retains a complex microbial ecosystem, which performs crucial functions that impact on host health. Several studies have indicated that intestinal dysbiosis may impact on the establishment of life-threatening intestinal diseases such as colorectal cancer. An adenomatous polyp is the result of abnormal tissue growth, which is benign but is considered to be associated with a high risk of developing colorectal cancer, based on its grade of dysplasia. Development of diagnostic tools that are based on surveying the gut microbiota and are aimed at early detection of colorectal cancer represent highly desirable target. For this purpose, we performed a pilot study in which we applied a metataxonomic analysis based on 16S rRNA gene sequencing approach to unveil the composition of microbial communities of intestinal polyps. Moreover, we performed a meta-analysis involving the reconstructed microbiota composition of adenomatous polyps and publicly available metagenomics datasets of colorectal cancer. These analyses allowed the identification of microbial taxa such as Faecalibacterium, Bacteroides and Romboutsia, which appear to be depleted in cancerogenic mucosa as well as in adenomatous polyps, thus representing novel microbial biomarkers associated with early tumor formation. Furthermore, an absolute quantification of Fusubacterium nucleatum in polyps further compounded the important role of this microorganism as a valuable putative microbial biomarker for early diagnosis of colorectal cancer.


Assuntos
Pólipos Adenomatosos/diagnóstico , Bactérias/classificação , Biomarcadores/análise , Neoplasias Colorretais/diagnóstico , Pólipos Intestinais/diagnóstico , Microbiota/genética , Mucosa/metabolismo , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/microbiologia , Idoso , Bactérias/genética , Bactérias/isolamento & purificação , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Feminino , Microbioma Gastrointestinal , Humanos , Pólipos Intestinais/genética , Pólipos Intestinais/microbiologia , Masculino , Metagenômica , Mucosa/microbiologia , Projetos Piloto , Prognóstico , RNA Ribossômico 16S/genética
4.
Microb Pathog ; 112: 274-278, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28987619

RESUMO

Some Escherichia coli strains of phylogroup B2 harbor a (pks) pathogenicity island that encodes a polyketide-peptide genotoxin called colibactin. It causes DNA double-strand breaks and megalocytosis in eukaryotic cells and it may contribute to cancer development. Study of bacterial community that colonizes the adenomatous polyp lesion, defined as precancerous lesions, could be helpful to assess if such pathogenic bacteria possess a role in the polyp progression to cancer. In this cross-sectional study, a total of 1500 E. coli isolates were obtained from biopsies of patients presenting adenomatous colon polyps, the normal tissues adjacent to the polyp lesion and patients presenting normal mucosa. pks island frequency, phylogenetic grouping, fingerprint genotyping, and virulence gene features of pks positive (pks+) E. coli isolates were performed. We found pks+E. coli strongly colonize two patients presenting polypoid lesions and none were identified in patients presenting normal mucosa. Predominant phylogroups among pks+E. coli isolates were B2, followed by D. Clustering based on fragment profiles of composite analysis, typed the pks+ isolates into 5 major clusters (I-V) and 17 sub-clusters, demonstrating a high level of genetic diversity among them. The most prevalent virulence genes were fimH and fyuA (100%), followed by vat (92%), hra and papA (69%), ibeA (28%), and hlyA (25%). Our results revealed that pks+E. coli can colonize the precancerous lesions, with a high distribution in both the polyp lesions and in normal tissues adjacent to the lesion. The high differences in fingerprinting patterns obtained indicate that pks+E. coli strains were genetically diverse, possibly allowing them to more easily adapt to environmental variations.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/classificação , Escherichia coli/genética , Variação Genética , Pólipos Intestinais/microbiologia , Filogenia , Fatores de Virulência/genética , Adesinas de Escherichia coli/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Biópsia , Estudos Transversais , DNA Bacteriano/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Proteínas de Fímbrias/genética , Ilhas Genômicas , Genótipo , Proteínas Hemolisinas/genética , Humanos , Itália , Proteínas de Membrana/genética , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Peptídeos/genética , Policetídeos , Receptores de Superfície Celular/genética , Virulência
5.
Asian Pac J Cancer Prev ; 17(1): 341-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26838234

RESUMO

BACKGROUND: Colorectal polyps are common in Thailand, particularly in the northeastern region. The present study aimed to determine any correlation between Helicobacter pylori-associated gastritis and colorectal polyps in the Thai population. MATERIALS AND METHODS: A total of 303 patients undergoing esophagogastroduodenoscopy with colonoscopy for investigation of chronic abdominal pain participated in this study from November 2014 to October 2015. A diagnosis of Helicobacter pylori associated gastritis was made if the bacteria were seen on histopathological examination and a rapid urease test was positive. Colorectal polyps were confirmed by histological examination of colorectal biopsies. Patient demographic data were analyzed for correlations. RESULTS: The prevalence of colorectal polyps was 77 (25.4%), lesions being found more frequently in Helicobacter pylori infected patients than non-infected subjects [38.4% vs. 12.5%; Odds Ratio (OR) (95% CI): 2.26 (1.32 - 3.86), p < 0.01]. Patients with Helicobacter pylori - associated gastritis were at high risk of having adenomas featuring dysplasia [OR (95% CI): 1.15 (1.16 - 7.99); P = 0.02]. There was no varaition in location of polyps, age group, sex and gastric lesions with respect to Helicobacter pylori status. CONCLUSIONS: This study showed that Helicobacter pylori associated gastritis is associated with an increased risk of colorectal polyps, especially adenomas with dysplasia in the Thai population. Patients with Helicobacter pylori-associated gastritis may benefit from concurrent colonoscopy for diagnosis of colorectal polyps as a preventive and early treatment for colorectal cancer.


Assuntos
Neoplasias Colorretais/etiologia , Gastrite/complicações , Gastrite/microbiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/patogenicidade , Pólipos Intestinais/etiologia , Adenoma/etiologia , Adenoma/microbiologia , Adolescente , Adulto , Idoso , Colonoscopia/métodos , Neoplasias Colorretais/microbiologia , Estudos Transversais , Feminino , Infecções por Helicobacter/microbiologia , Humanos , Pólipos Intestinais/microbiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tailândia , Adulto Jovem
6.
Pathol Res Pract ; 210(7): 440-3, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24767254

RESUMO

It remains unclear whether or not human intestinal spirochetosis (HIS) has any associated symptoms or lesions. In this study, we assessed the prevalence of HIS in sessile serrated adenomas/polyps (SSA/Ps) and their possible association. Following identification of early cecal cancer with SSA/P accompanied by a colonization of HIS, we went on to conduct a retrospective case-control study using endoscopically resected SSA/P specimens to examine the frequency of HIS infection in SSA/Ps. Nineteen SSA/P cases and 172 controls were obtained. The rate of HIS infection was significantly higher at 52.6% (10/19) in the SSA/P cases compared to the controls at 8.1% (14/172). Our SSA/P series were associated with a remarkably higher rate of HIS than controls or than previously reported. This is the first report to provide evidence for potential association between HIS and SSA/Ps.


Assuntos
Adenoma/microbiologia , Neoplasias Intestinais/microbiologia , Pólipos Intestinais/microbiologia , Infecções por Spirochaetales/complicações , Infecções por Spirochaetales/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Adulto Jovem
7.
Mol Carcinog ; 46(1): 42-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16929480

RESUMO

We previously reported that two dietary regimens, calorie restriction (CR) and a high olive oil-containing diet supplemented with a freeze-dried fruit and vegetable extract (OFV), reduced the development of intestinal adenomas in Apc(Min) mice by 57% and 33%, respectively, compared to control mice fed a defined diet ad libitum. The OFV diet was designed to have a strong effect on the composition of the intestinal microbiota through its high content of fiber, which represents a major source of fermentable substrate for the gut bacteria. We hypothesized that some of the observed effects of diet on intestinal carcinogenesis might be mediated by diet-related changes in the bacterial species that thrive in the gut. Therefore, we determined by fluorescent in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE) how the dietary interventions affected the composition of the intestinal microbiota, and we characterized specific microbiota changes that were associated with diet and reduced intestinal carcinogenesis. The OFV diet changed the overall composition of the intestinal microbiota, smaller changes were observed for the CR diet. Furthermore, we detected a 16S rDNA fragment associated with mice that did not develop polyps. Sequence analysis suggested that hitherto unidentified bacteria belonging to the family Lachnospiraceae (order Clostridiales) were its source. Thus, these bacteria may be an indicator of intestinal conditions associated with reduced intestinal carcinogenesis in Apc(Min) mice.


Assuntos
Polipose Adenomatosa do Colo/microbiologia , Bactérias/isolamento & purificação , Dieta , Trato Gastrointestinal/microbiologia , Genes APC/fisiologia , Neoplasias Intestinais/microbiologia , Adenoma/genética , Adenoma/metabolismo , Adenoma/prevenção & controle , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/prevenção & controle , Animais , Bactérias/classificação , Bactérias/genética , Contagem de Colônia Microbiana , Frutas , Hibridização in Situ Fluorescente , Neoplasias Intestinais/genética , Neoplasias Intestinais/prevenção & controle , Pólipos Intestinais/genética , Pólipos Intestinais/microbiologia , Pólipos Intestinais/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Azeite de Oliva , Óleos de Plantas/administração & dosagem , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Verduras
8.
Aliment Pharmacol Ther ; 23(2): 255-63, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16393305

RESUMO

BACKGROUND: Studies on probiotics mainly base their results on faecal samples, which may not represent the situation in the mucosa of distal and proximal colon. AIM: In a placebo-controlled study, to assess the effect of Lactobacillus plantarum 299v on the bacterial composition of faecal vs. mucosal samples. METHODS: Twenty-nine patients undergoing colonoscopic examination for polyps consumed a twice-daily drink with or without L. plantarum 299v (10(11) CFU/day) for 2 weeks. Faecal samples were collected before and after consumption. During colonoscopy, biopsies were collected from the ascending colon and rectum. The faecal and mucosal bacterial concentrations and prevalence were determined. RESULTS: L. plantarum 299v significantly increased the concentration of faecal lactic acid bacteria, lactobacilli and clostridia, and was identified in two rectal biopsies but not in the ascending colon biopsies of probiotic-treated subjects. Concentrations and prevalence in ascending colon and rectum biopsies were comparable, but were significantly lower compared with faecal samples. CONCLUSIONS: After probiotic consumption, a significant increase in the faecal concentration of lactobacilli was found but concentrations were low in biopsies. The bacterial composition in biopsies of the ascending colon and rectum did not differ based on culture techniques. To further elucidate the modes of action of probiotics, it might be necessary to study differences in colonization with molecular techniques.


Assuntos
Bebidas , Fezes/microbiologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum , Probióticos/uso terapêutico , Biópsia/métodos , Clostridium/isolamento & purificação , Colo/microbiologia , Contagem de Colônia Microbiana , Método Duplo-Cego , Feminino , Humanos , Pólipos Intestinais/microbiologia , Lactobacillus plantarum/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Reto/microbiologia
10.
J Exp Clin Cancer Res ; 18(2): 255-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10464716

RESUMO

The incidence of multiple polyps and number of polyps per mouse were significantly lower in conventionalized (CVz), and chloroform-resistant bacteria (CRB)- or fusiform bacteria (FB)-associated mice than in germfree (GF) BALB/c mice. The concentration of fecal fatty acids was also higher in mice associated with either CRB or FB than in GF mice. The incidence of multiple polyps and number of polyps per mouse were significantly correlated with the concentration of fatty acids in the feces of CVz and CRB-GB mice. This study demonstrated that inhibition of multiple polyps in the small intestine of BALB/c mice was affected by the production of intestinal fatty acids.


Assuntos
Vida Livre de Germes , Neoplasias Intestinais/etiologia , Neoplasias Intestinais/microbiologia , Pólipos Intestinais/etiologia , Pólipos Intestinais/microbiologia , Intestino Delgado/microbiologia , Neoplasias Primárias Múltiplas/etiologia , Neoplasias Primárias Múltiplas/microbiologia , Animais , Ácidos Graxos/análise , Fezes/química , Feminino , Neoplasias Intestinais/metabolismo , Pólipos Intestinais/metabolismo , Intestino Delgado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Primárias Múltiplas/metabolismo
11.
Cancer Lett ; 131(2): 153-6, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9851247

RESUMO

The incidence of polyposis and the number of polyps per mouse were significantly lower in conventionalized (CVz) mice than in germ-free (GF) mice. There was no significant difference in the average number of polyps between GF and gnotobiotic (GB) mice monoassociated with the various strains of intestinal bacteria. However, the incidence of polyposis and the number of polyps per mouse were significantly lower for mice associated with either chloroform-resistant bacteria (CRB) or fusiform bacteria (FB) than for GF mice. This study demonstrated that polyposis was suppressed by FB and CRB in the small intestine of BALB/c mice.


Assuntos
Fenômenos Fisiológicos Bacterianos , Pólipos Intestinais/microbiologia , Intestinos/microbiologia , Animais , Vida Livre de Germes , Camundongos , Camundongos Endogâmicos BALB C
12.
J Clin Gastroenterol ; 23(1): 53-4, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8835902

RESUMO

Although there have been several reports of hyperplastic gastric polyps associated with persistent Helicobacter pylori gastritis, the association of H. pylori infection with metaplastic polyps in the duodenum has not hitherto been described. After a 52-year-old man had a single episode of hematemesis, endoscopy showed a smooth polyp 1 cm in greatest dimension formed by a proliferation of gastric epithelial cells of fundic and antral type found in the duodenal bulb. The outer surface was entirely covered with a single layer of hyperplastic columnar epithelium with many H. pylori organisms. After administration of metronidazole 500 mg, omeprazole 20 mg for 4 weeks, and clarithromycin 250 mg twice a day for 2 weeks, endoscopy showed a decrease in size of the duodenal polyp. At 12 weeks there was complete regression of the polyp. This report documents a new and unusual finding: resolution of a gastric metaplastic polyp in the duodenum associated with cure of H. pylori.


Assuntos
Neoplasias Duodenais/microbiologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Pólipos Intestinais/microbiologia , Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Claritromicina/uso terapêutico , Neoplasias Duodenais/prevenção & controle , Humanos , Pólipos Intestinais/prevenção & controle , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Omeprazol/uso terapêutico , Ranitidina/uso terapêutico , Fatores de Tempo
13.
Appl Environ Microbiol ; 61(9): 3202-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7574628

RESUMO

The fecal floras of polyp patients, Japanese-Hawaiians, North American Caucasians, rural native Japanese, and rural native Africans were compared. The polyp patients and Japanese-Hawaiians were considered to be groups at high risk of colon cancer, and the rural native Japanese and rural native Africans were considered to be groups at low risk. The North American Caucasians were found to have a flora composition intermediate between these two groups. Fifteen bacterial taxa from the human fecal flora were significantly associated with high risk of colon cancer, and five were significantly associated with low risk of colon cancer. Total concentrations of Bacteroides species and, surprisingly, Bifidobacterium species were generally positively associated with increased risk of colon cancer. Some Lactobacillus species and Eubacterium aerofaciens, which also produces major amounts of lactic acid, showed closest associations with low risk of colon cancer.


Assuntos
Neoplasias do Colo/etiologia , Intestinos/microbiologia , Bacteroides/isolamento & purificação , Bifidobacterium/isolamento & purificação , Eubacterium/isolamento & purificação , Fezes/microbiologia , Fusobacterium/isolamento & purificação , Havaí , Humanos , Pólipos Intestinais/complicações , Pólipos Intestinais/microbiologia , Japão/etnologia , Lactobacillus/isolamento & purificação , América do Norte , Fatores de Risco , População Rural , África do Sul , População Branca
14.
Am J Gastroenterol ; 80(1): 42-6, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3966453

RESUMO

We designed a study to evaluate the fecal carrier rate of Streptococcus bovis in patients with endoscopically proven colonic polyps. Benign polyps (n = 63), i.e., hyperplastic, inflammatory, and juvenile, had a similar fecal carrier rate as the normal control colons. Colons with polyps that are at increased risk for malignant degeneration (n = 62), i.e., tubulovillous and villous adenomas, and colons with carcinoma (n = 18), had a statistically significant increase (p less than 0.05) in the fecal carrier rate for S. bovis over the benign colon group. Overall, the incidence of S. bovis carriage in all colons with polyps was intermediary between normal colons and colons with carcinoma although the numbers did not achieve statistical significance.


Assuntos
Neoplasias do Colo/microbiologia , Fezes/microbiologia , Pólipos Intestinais/microbiologia , Lesões Pré-Cancerosas/microbiologia , Streptococcus/isolamento & purificação , Adenoma/etiologia , Adenoma/microbiologia , Adenoma/patologia , Idoso , Carcinoma/etiologia , Carcinoma/microbiologia , Carcinoma/patologia , Portador Sadio , Transformação Celular Neoplásica , Colo/microbiologia , Neoplasias do Colo/etiologia , Neoplasias do Colo/patologia , Feminino , Humanos , Pólipos Intestinais/etiologia , Pólipos Intestinais/patologia , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/etiologia , Lesões Pré-Cancerosas/patologia
16.
Am J Gastroenterol ; 78(8): 469-75, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6603789

RESUMO

Eubacterium lentum and phenotypically similar organisms synthesize a steroid 21-dehydroxylase which converts biliary tetrahydrodeoxycorticosterone to pregnanolone. Tetrahydrodeoxycorticosterone, in contrast to pregnanolone, is carcinogenic for hamster embryonic cells (HECT test). In patients with recently diagnosed, untreated sigmoidal or rectal cancer the fecal concentration of 21-dehydroxylating organisms is reduced by more than 99% as compared with age-matched controls. The lack of fecal 21-dehydroxylating organisms, therefore, is a potential marker for the disorder. The role of steroid 21-dehydroxylase in the pathogenesis of colorectal cancer is unknown.


Assuntos
Neoplasias do Colo/metabolismo , Desoxicorticosterona/análogos & derivados , Fezes/análise , Neoplasias Retais/metabolismo , Esteroide 21-Hidroxilase/análise , Esteroide Hidroxilases/análise , Adulto , Idoso , Animais , Transformação Celular Neoplásica , Pré-Escolar , Neoplasias do Colo/microbiologia , Cricetinae , Desoxicorticosterona/análise , Comportamento Alimentar , Feminino , Humanos , Lactente , Pólipos Intestinais/microbiologia , Masculino , Pessoa de Meia-Idade , Testes de Mutagenicidade , New York , Pregnanolona/análise , Neoplasias Retais/microbiologia , Risco , África do Sul
18.
Cancer Res ; 38(12): 4458-62, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-719630

RESUMO

It has been postulated that the intestinal anaerobes play a role in the etiology of large bowel cancer. This study was designed to characterize and compare the fecal anaerobes of patients with large bowel cancer, patients with nonhereditary large bowel polyps, and healthy control subjects. Although some distributional variations of the anaerobic genera were observed among the study groups, significant differences in fecal anaerobic microflora and total aerobic counts were not noted. This suggests that taxonomic grouping of fecal bacteria is an inadequate measure of relative risk of developing large bowel cancer. However, the fecal microbial 7alpha-dehydroxylase and cholesterol dehydrogenase activities of large bowel cancer patients and patients with nonhereditary large bowel polyps were significantly higher than those of healthy control subjects. On the other hand, no significant difference in fecal microbial beta-glucuronidase activity was noted among the study groups. It may be that assessment of the total metabolic activities of the intestinal microflora will provide a better understanding of their potential role in the genesis of large bowel cancer.


Assuntos
Bactérias/isolamento & purificação , Neoplasias do Colo/microbiologia , Fezes/microbiologia , Pólipos Intestinais/microbiologia , Neoplasias Retais/microbiologia , Adulto , Bactérias/enzimologia , Neoplasias do Colo/etiologia , Dieta , Fezes/enzimologia , Feminino , Humanos , Pólipos Intestinais/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/etiologia , Risco
20.
Am J Clin Nutr ; 29(12): 1455-60, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-793371

RESUMO

Because of the potential significance of secondary bile acids and cholesterol metabolites formed by the intestinal microflora in the pathogenesis of colon cancer, fecal microbial 7alpha-dehydroxylase and cholesterol dehydrogenase activities were assayed in colorectal cancer patients, patients with adenomatous polyps, asymptomatic controls, and normal controls. The mean 7alpha-dehydroxylase activity per 100 mg of dry feces per 2 hr incubation for colorectal cancer patients was significantly greater than either asymptomatic controls or normal controls. Patients with polyps had greater activity than controls, but did not differ significantly from the cancer patients or asymptomatic controls. The mean cholesterol dehydrogenase activity for colorectal cancer patients was significantly greater than controls. Patients with polyps also had greater activity than controls. No differences in the level of fecal beta-glucuronidase activity were found among the four risk groups. These data support the concept that patients with colorectal cancer are more able to convert primary bile acids and cholesterol to microbial products in colon contents than are controls. Such differences in the activity of intestinal microflora may serve as biochemical indicators that will reflect the enzymic activity of the fecal flora as well as the key intraluminal compounds in identifying populations at different risk for developing colorectal cancer.


Assuntos
Neoplasias do Colo/microbiologia , Fezes/microbiologia , Glucuronidase/metabolismo , Oxigenases de Função Mista/metabolismo , Oxirredutases/metabolismo , Ácidos e Sais Biliares/metabolismo , Colestanol/metabolismo , Colesterol/metabolismo , Feminino , Humanos , Pólipos Intestinais/microbiologia , Masculino , Pessoa de Meia-Idade
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