Preneoplastic Colorectal Lesions Research Articles

Colonic Microbial Abundances Predict Adenoma Formers.

We aimed to examine associations between the oral, fecal, and mucosal microbiome communities and adenoma formation. Data are limited regarding the relationships between microbiota and preneoplastic colorectal lesions. Individuals undergoing screening colonoscopy were prospectively enrolled and divided into adenoma and nonadenoma formers. Oral, fecal, nonadenoma and adenoma-adjacent mucosa were collected along with clinical and dietary information. 16S rRNA gene libraries were generated using V4 primers. DADA2 processed sequence reads and custom R-scripts quantified microbial diversity. Linear regression identified differential taxonomy and diversity in microbial communities and machine learning identified adenoma former microbial signatures. One hundred four subjects were included, 46% with adenomas. Mucosal and fecal samples were dominated by Firmicutes and Bacteroidetes whereas Firmicutes and Proteobacteria were most abundant in oral communities. Mucosal communities harbored significant microbial diversity that was not observed in fecal or oral communities. Random forest classifiers predicted adenoma formation using fecal, oral, and mucosal amplicon sequence variant (ASV) abundances. The mucosal classifier reliably diagnosed adenoma formation with an area under the curve (AUC) = 0.993 and an out-of-bag (OOB) error of 3.2%. Mucosal classifier accuracy was strongly influenced by five taxa associated with the family Lachnospiraceae, genera Bacteroides and Marvinbryantia, and Blautia obeum. In contrast, classifiers built using fecal and oral samples manifested high OOB error rates (47.3% and 51.1%, respectively) and poor diagnostic abilities (fecal and oral AUC = 0.53). Normal mucosa microbial abundances of adenoma formers manifest unique patterns of microbial diversity that may be predictive of adenoma formation.

Weight loss with exercise improves muscle architecture and progenitor cell populations compared with weight loss alone in mice with preneoplastic colorectal lesions.

Weight loss and exercise reduce colorectal cancer (CRC) risk in persons with obesity. Whether weight loss and exercise effect myofiber characteristics and muscle stem/progenitor cell populations in mice with preneoplastic colorectal lesions, a model of CRC risk, is unknown. To address this gap, male C57Bl/6J mice were fed a high-fat diet (HFD) to induce obesity or a control (CON) diet prior to azoxymethane injection to induce preneoplastic colorectal lesions. The HFD group was then randomized to weight loss conditions that included (1) switching to the CON diet only (HFD-SED) or switching to the CON diet with treadmill exercise training (HFD-EX). Average myofiber cross-sectional area was not different between groups. There were more smaller-sized fibres in HFD-EX (p < 0.05 vs. CON), and more fibrosis in HFD-SED (p < 0.05 vs. HFD-EX and CON). There was a trend for more committed (Pax7+MyoD+) myoblasts (p = 0.059) and more fibro-adipogenic progenitors in HFD-EX (p < 0.05 vs. CON). Additionally, the canonical pro-inflammatory marker p-NF-κB was markedly reduced in the interstitium of HFD-EX (p < 0.05 vs. CON and HFD-SED). Our findings suggest that in mice with preneoplastic colorectal lesions, HFD followed by weight loss with exercise reduces muscle fibrosis and results in a higher content of muscle stem/progenitor cells. Novelty: Exercise improves muscle architecture in mice with preneoplastic colorectal lesion Exercise increases fibro/adipogenic progenitors and reduces inflammatory signaling in mice with preneoplastic colorectal lesions.

Relationship between Streptococcus gallolyticus Infective Endocarditis and Pre-Neoplastic Colorectal Lesions

Colorectal cancer is associated with Infective Endocarditis (IE) due to specific gut pathogens, such as Streptococcus gallolyticus subspecies, that use tumor presence as a point of blood entry. However, the association between Streptococcus gallolyticus related IE and pre-cancerous colorectal lesions like dysplastic adenomas is unclear. Seventy-one patients diagnosed with IE who underwent colonoscopy in the extension study during admission were included in a clinical, microbiological and imaging follow-up, between January 2008 and December 2020. Pre-cancerous lesions were divided as high and low-grade dysplasia based on World Health Organization criteria. Colorectal cancer was defined as the presence of malignant cell beyond the muscularis mucosa. Twenty-two IE patients (31%) presented colorectal lesions: 8 (36%) colorectal cancer and 14 (64%) pre-cancerous lesions [14% high degree (n = 2); 86% low degree (n = 12)]. Both, colorectal cancer (25% Vs 2%; p = 0.007) and pre-neoplastic lesions (50% Vs 2%; p<0.001) were related with higher prevalence of IE caused by Streptococcus gallolyticus. Additionally, the subgroup of low grade pre-cancerous lesions also showed this association (50% Vs 2%; p<0.001). Pre-cancerous colorectal lesions are associated with Streptococcus gallolyticus IE. These results suggest that high and low degree colorectal lesions may also act as a gateway for gut pathogens.

P661 Relationship between streptococcal infective endocarditis and preneoplastic colorectal lesions

Abstract Background Colorectal cancer is associated with infective endocarditis (IE), due to specific gut pathogens like streptococcus Gallolyticus that use the tumor presence as a point of blood entry. However, the association between streptococcal IE and pre-cancerous lesions such as dysplastic adenomas is unknown. Objectives To determine the association with pre-neoplastic colorectal lesions and streptococcal IE. Methods Two hundred eighty consecutive patients with IE were included in a protocol of clinical, microbiological and imaging follow-up, between January 2008 and December 2018. Precancerous lesions were divided as high and low-grade dysplasia based on World Health Organization criteria. Colorectal cancer was defined as the presence of malignant cell beyond the muscularis mucosa. Results A colonoscopy was performed in 81 patients (29%) and 26 of them (32%) presented colorectal lesions: 10 (38%) colorectal cancer and 16 (62%) precancerous lesions (12% high degree (n = 2); 88% low degree (n = 14)). Both, colorectal cancer (20% vs 11%; p = 0.02) and preneoplastic lesions (44% vs 8%; p &amp;lt; 0.001) were associated with higher incidence of streptococcus Gallolyticus IE (Figure 1). Additionally, the subgroup of precancerous lesions with low degree also showed this association (43% vs 9%; p = 0.001). Conclusions Precancerous colorectal lesions are also associated with streptococcus Gallolyticus IE, even low-grade lesions. Hence, it is necessary to rule out occult neoplastic and preneoplastic colorectal lesions with colonoscopy in these patients. Figure 1: Relationship between S. Gallolyticus IE and colorectal lesions. a Statistical significance between colorectal cancer and S. Gallolyticus IE. b Statistical significance between preneoplastic colorectal lesions and S. Gallolyticus IE. Abstract P661 Figure.

3328Relationship between streptococcal infective endocarditis and pre-neoplastic colorectal lesions

Abstract Background Colorectal cancer is associated with infective endocarditis (IE), due to specific gut pathogens like streptococcus Gallolyticus that use the tumor presence as a point of blood entry. However, the association between streptococcal IE and pre-cancerous lesions such as dysplastic adenomas is unknown. Objectives To determine the association with pre-neoplastic colorectal lesions and streptococcal IE. Methods Two hundred eighty consecutive patients with IE were included retrospectively in a protocol of clinical, microbiological and imaging follow-up, between January 2008 and December 2018. Pre-cancerous lesions were divided as high and low-grade dysplasia based on World Health Organization criteria. Colorectal cancer was defined as the presence of malignant cell beyond the muscularis mucosa. Results Fifty patients (18%) presented neoplastic or pre-neoplastic lesions, and 26 of them (52%) were colorectal: 10 (38%) colorectal cancer and 16 (62%) precancerous lesions (12% high degree (n=2); 88% low degree (n=14)). Both, colorectal cancer (20% vs 5%; p=0.03) and pre-neoplastic lesions (44% vs 3%; p&lt;0.05) were associated with higher incidence of streptococcus Gallolyticus IE (Figure 1). Additionally, 42% (n=11) of colorectal lesions were diagnosed in the IE event. No significant differences were found about cardiac surgery and in-hospital mortality in these patients. Figure 1. Relationship between S. Gallolyticus IE and colorectal lesions. (a) Statistical significance between colorectal cancer and S. Gallolyticus IE. (b) Statistical significance between pre-neoplastic colorectal lesions and S. Gallolyticus IE. Conclusions Pre-cancerous colorectal lesions are also associated with streptococcus Gallolyticus IE, even low-grade lesions. Hence, it is necessary to rule out occult neoplastic and also pre-neoplastic colorectal lesions with colonoscopy in these patients.

Extract of the Bark of Bathysa cuspidataAttenuates the Development of Chemically-Induced Preneoplastic Colorectal Lesions in Rats

The aim of this study was to investigate the effect of the bark extractBathysa cuspidata on chemically induced preneoplastic colorectal lesions in Wistar rats. Forty male rats were randomly divided into four groups (n = 10 each): saline (control group, oral administration of saline solution 0.9%); dimethylsulfoxide (DMSO, vehicle control), B200 (treated with 200 mg/kg bark extract ofB. cuspidata), and B400 (treated with 400 mg/kg bark extract ofB. cuspidata). Administration of treatments was carried out by the gavage. The animals received four subcutaneous injections of 1,2-dimethylhydrazine (DMH, 40 mg/kg) in the initial two weeks of the experiment to induce preneoplastic colorectal lesions. After 15 weeks, the animals were euthanized and the presence of aberrant crypt foci (ACF), body weight, biochemical analyses, and oxidative stress markers were measured. The extract ofB. cuspidata decreased the levels of superoxide dismutase (SOD), but did not influence the levels of catalase (CAT), malondialdehyde (MDA), nitric oxide or protein carbonyl, compared with the saline group. The animals supplemented with a more concentratedB. cuspidata extract (B400) showed a significant reduction in the number of ACF in all the portions of the intestinal mucosa. The study demonstrated that the bark extract ofB. cuspidata at 400 mg/kg reduced the preneoplastic colorectal lesions in an animal model of colon cancer and that the effect could be dose-dependent.

Association between Diverticular Disease and Pre-Neoplastic Colorectal Lesions in an Urban African-American Population

Background: It is unclear whether there is a shared pathway in the development of diverticular disease (DD) and potentially neoplastic colorectal lesions since both diseases are found in similar age groups and populations. Aim: To determine the association between DD and colorectal pre-neoplastic lesions in an African-American urban population. Methods: Data from 1986 patients who underwent colonoscopy at the Howard University Hospital from January 2012 through December 2012 were analyzed for this study. The presence of diverticula and polyps was recorded using colonoscopy reports. Polyps were further classified into adenoma or hyperplastic polyp based on histopathology reports. Multiple logistic regression was done to analyze the association between DD and colonic lesions. Results: Of the 1986 study subjects, 1,119 (56%) were females, 35% had DD and 56% had at least one polyp. There was a higher prevalence of polyps (70 vs. 49%; OR = 2.3; 95% CI: 1.9-2.8) and adenoma (43 vs. 25%; OR = 2.0; 95% CI: 1.7-2.5) in the diverticular vs. non-diverticula patients. Among patients who underwent screening colonoscopy, the presence of diverticulosis was associated with increased odds of associated polyps (OR = 9.9; 95% CI: 5.4-16.8) and adenoma (OR = 5.1; 95% CI: 3.4-7.8). Conclusion: Patients with DD are more likely to harbor colorectal lesions. These findings call for more vigilance on the part of endoscopists during colonoscopy in patients known to harbor colonic diverticula.

Promoter methylation of tumor suppressor genes in pre-neoplastic lesions; potential marker of disease recurrence.

BackgroundEpigenetic alterations of specific genes have been reported to be related to colorectal cancer (CRC) transformation and would also appear to be involved in the early stages of colorectal carcinogenesis. Little data are available on the role of these alterations in determining a different risk of colorectal lesion recurrence. The aim of the present study was to verify whether epigenetic alterations present in pre-neoplastic colorectal lesions detected by colonoscopy can predict disease recurrence.MethodsA retrospective series of 78 adenomas were collected and classified as low (35) or high-risk (43) for recurrence according to National Comprehensive Cancer Network guidelines. Methylation alterations were analyzed by the methylation-specific multiplex ligation probe assay (MS-MLPA) which is capable of quantifying methylation levels simultaneously in 24 different gene promoters. MS-MLPA results were confirmed by pyrosequencing and immunohistochemistry.ResultsHigher levels of methylation were associated with disease recurrence. In particular, MLH1, ATM and FHIT gene promoters were found to be significantly hypermethylated in recurring adenomas. Unconditional logistic regression analysis used to evaluate the relative risk (RR) of recurrence showed that FHIT and MLH1 were independent variables with an RR of 35.30 (95% CI 4.15-300.06, P = 0.001) and 17.68 (95% CI 1.91-163.54, P = 0.011), respectively.ConclusionsHistopathological classification does not permit an accurate evaluation of the risk of recurrence of colorectal lesions. Conversely, results from our methylation analysis suggest that a classification based on molecular parameters could help to define the mechanisms involved in carcinogenesis and prove an effective method for identifying patients at high risk of recurrence.

Promoter methylation of tumor suppressor genes in pre-neoplastic lesions; potential marker of disease recurrence

Epigenetic alterations of specific genes have been reported to be related to colorectal cancer (CRC) transformation and would also appear to be involved in the early stages of colorectal carcinogenesis. Little data are available on the role of these alterations in determining a different risk of colorectal lesion recurrence. The aim of the present study was to verify whether epigenetic alterations present in pre-neoplastic colorectal lesions detected by colonoscopy can predict disease recurrence. A retrospective series of 78 adenomas were collected and classified as low (35) or high-risk (43) for recurrence according to National Comprehensive Cancer Network guidelines. Methylation alterations were analyzed by the methylation-specific multiplex ligation probe assay (MS-MLPA) which is capable of quantifying methylation levels simultaneously in 24 different gene promoters. MS-MLPA results were confirmed by pyrosequencing and immunohistochemistry. Higher levels of methylation were associated with disease recurrence. In particular, MLH1, ATM and FHIT gene promoters were found to be significantly hypermethylated in recurring adenomas. Unconditional logistic regression analysis used to evaluate the relative risk (RR) of recurrence showed that FHIT and MLH1 were independent variables with an RR of 35.30 (95% CI 4.15-300.06, P = 0.001) and 17.68 (95% CI 1.91-163.54, P = 0.011), respectively. Histopathological classification does not permit an accurate evaluation of the risk of recurrence of colorectal lesions. Conversely, results from our methylation analysis suggest that a classification based on molecular parameters could help to define the mechanisms involved in carcinogenesis and prove an effective method for identifying patients at high risk of recurrence.

Naringin accelerates the regression of pre-neoplastic lesions and the colorectal structural reorganization in a murine model of chemical carcinogenesis

The aim of this study was to investigate the effect of Naringin on pre-neoplastic colorectal lesions induced by chemical carcinogen in rats. Female Wistar rats weighing 130.8±27.1g received weekly one subcutaneous injection of 1,2-dimethylhydrazine (DMH, 20mg/kg) for 10weeks. The animals were divided into 5 groups with 6 animals in each group. Group 1: 0.9% saline; Group 2: DMH+0.9% saline; Group 3: DMH+Naringin (10mg/kg); Group 4: DMH+Naringin (100mg/kg); Group 5: DMH+Naringin (200mg/kg). G2 and G3 showed a significant increase in ACF number, AgNOR/nucleus and mitosis compared to G1. G4 and G5 presented a significant reduction in these parameters compared to G2. The number of cells producing acidic and neutral mucins, red blood cells and the level of antioxidant minerals, such as copper, magnesium, selenium and zinc, were significantly reduced in G2 and G3, but similar in G4 and G5 compared to G1. Naringin, especially at 200mg/kg, was effective in reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects may be due to reduction in cellular proliferation and tissue levels of iron together with the recovery of antioxidant mineral levels induced by this flavonoid.

The flavonoid chrysin attenuates colorectal pathological remodeling reducing the number and severity of pre-neoplastic lesions in rats exposed to the carcinogen 1,2-dimethylhydrazine

Phenolic compounds are naturally occurring, bioactive substances with marked antioxidant and anti-inflammatory potential. The flavonoid chrysin, found in high levels in honey bee propolis, inhibits the activity of enzymes involved in carcinogenesis. We have investigated the effect of chrysin on pre-neoplastic colorectal lesions (ACF, aberrant crypt foci) in a rat model of chemical carcinogenesis induced by 1,2-dimethylhydrazine (DMH). Female Wistar rats weighing 137.2 ± 24.3 g received weekly one subcutaneous injection of DMH (20 mg/kg) for 10 weeks. The animals were divided into five groups each with seven animals: Group 1, 0.9% saline; Group 2, DMH+0.9% saline; Group 3, DMH+chrysin (10 mg/kg); Group 4, DMH+chrysin (100 mg/kg); Group 5, DMH+chrysin (200 mg/kg). Groups 2 and 3 showed a significant increase in ACF number, nucleolus organizer regions per enterocyte nucleus and nitrite/nitrate serum levels compared with Group 1. Groups 4 and 5 presented a significant reduction in all these parameters compared with Group 2. The levels of antioxidant minerals (copper, magnesium, selenium, zinc) and the number of enteroendocrine and mucin-producing cells were significantly reduced in Groups 2 and 3 but were similar in Groups 4 and 5 compared with Group 1. Chrysin, at 100 mg/kg and 200 mg/kg, was effective in attenuating pathological colorectal remodeling, reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects might be attributable to the recovery of antioxidant mineral levels, a reduction in systemic nitrosative stress and an inhibition of the cellular proliferation induced by this flavonoid.

Abstract 3174: Colorectal cancer specific host response signatures achieved by next generation sequencing and multiplex RT-qPCR

Abstract Background: colorectal cancer (CRC) develops over a period of several years and is often preceded by adenoma formation. Detection rates for colorectal adenoma and early CRC, however, are unsatisfactory due to low compliance towards invasive screening procedures such as colonoscopy. There is a large unmet screening need calling for an accurate, non invasive and cost effective test to screen for early neoplastic and preneoplastic colorectal lesions. We developed a screening test aimed at detecting precancerous lesions and CRC at early stages, based on a multigene expression profiling on peripheral blood mononuclear cells (PBMC). Methods: 92 colonoscopy screened subjects served as a training set. Colonoscopy revealed 21 patients had CRC, 30 adenomas larger than 1cm and 41 had no detectable lesions. 16 mL of blood was collected from each individual and PBMC were purified using Vacutainer® CPT tubes (Becton Dickinson). Total RNA was extracted and a whole genome expression analysis by digital gene expression TAG profiling (Illumina) was performed on a subset of these 92 subjects. Deep sequencing generated on average 1.5 million reads per sample and they matched to 20288 different transcripts. Different univariate and multivariate statistical methods were then applied in order to find genes differentially expressed between control, adenoma and CRC (pvalue &amp;lt;0.05). 45 candidate genes discovered with TAG profiling were then analytically validated using a multiplex RT qPCR methodology. All candidate genes were normalized with a stable normalization strategy in order to obtain comparable results across assays. An additional set of 57 candidate genes was also added based on literature review and validated using the multiplex RT qPCR methodology. Multiple statistical methods were applied on the normalized PCR data and 43 biomarkers, with significant p-value (&amp;lt;0.01) for most of the methods, were selected. Two distinct molecular signatures were derived from the normalized biomarker combinations based on penalized logistic. Results: a validation set was defined using random resampling (bootstrapping method), leading to the separation of individuals without lesion from those with CRC (Se 70%, Sp 94%, AUC 0.89) and from those with adenoma larger than 1cm (Se 67%, Sp 87%, AUC 0.80). In addition, as a test set, the organ and disease specificity of these signatures was confirmed by means of patients with other cancer types and inflammatory bowel diseases. Conclusion: Next generation sequencing is a powerful research tool to define specific signatures for precancerous and early cancerous lesions when coupled to multiplex RT qPCR and normalized with specific reference genes. A prospective, multi-centric, pivotal study is underway in order to validate these results in a larger cohort. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3174. doi:10.1158/1538-7445.AM2011-3174

Evaluation of Agaricus blazei in vivo for antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities

The development of various types of cancer results from the interaction among endogenous, environmental and hormonal factors, where the most notable of these factors is diet. The aim of the present study was to determine the antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities of Agaricus blazei. The test antigenotoxicity (Comet Assay) and anticarcinogenic (Test of Aberrant Crypt Foci) assess changes in DNA and/or intestinal mucosa that correlate to cancer development. Tests of phagocytosis in the spleen and differential count in blood cells allow the inference of modulation of the immune system as well as to propose a way of eliminating cells with DNA damage. Supplementation with the mushroom was carried out under pre-treatment, simultaneous treatment, post-treatment and pre-treatment+continuous conditions. Statistical analysis demonstrated that the mushroom did not have genotoxic activity but showed antigenotoxic activity. Supplementation caused an increase in the number of monocytes and in phagocytic activity, suggesting that supplementation increases a proliferation of monocytes, consequently increasing phagocytic capacity especially in the groups pre-treatment, simultaneous and pre-treatment+continuous. The data suggest that A. blazei could act as a functional food capable of promoting immunomodulation which can account for the destruction of cells with DNA alterations that correlate with the development of cancer, since this mushroom was demonstrated to have a preventive effect against pre-neoplastic colorectal lesions evaluated by the aberrant crypt foci assay. According to these results and the literature, it is believed that supplementation with A. blazei can be an efficient method for the prevention of cancer as well as possibly being an important coadjuvant treatment in chemotherapy.

56 P Platelet-derived endothelial cell growth factor in preneoplastic and neoplastic colorectal lesions

56 P Platelet-derived endothelial cell growth factor in preneoplastic and neoplastic colorectal lesions

Determination of p185 and adenylosuccinate lyase (ASL) activity in preneoplastic colon lesions and intestinal mucosa of human subjects

Objectives: The HER2 gene has been found amplified in a number of human adenocarcinoma leading to elevated levels of expression of its encoded product, p185 protein. Because little information is available on the tissue and tumor specificity of this gene product, we studied the expression of p185 protein in preneoplastic colon lesions. Adenylosuccinate lyase (ASL, EC 4.3.2.2) is known to increase in malignancies such as colorectal, breast, and prostate cancer. In order to evaluate the potential of ASL as a tumor marker, its activity was determined and compared with the expression of p185. Design and methods: p185 was determined by an immunohistochemical procedure in patients with the preneoplastic lesions. ASL activity was evaluated in intestinal mucosa adjacent to colorectal cancers (patient group A) and in preneoplastic colorectal lesions (group B). The enzyme activity was evaluated in dialyzed supernatants, following the disappearance of substrate (adenylosuccinate AMP-S) and the formation of product (adenosine 5′-monophosphate -AMP), separated by high performance liquid chromatography. Results and conclusions: Increased expression of p185 and elevated ASL activity were observed in tubular and tubulo-villous adenoma and may, therefore, be associated with the early stages of colorectal cancer.