gut microbiota colorectal carcinoma

The gut microbiota, as the main member in gut microecology, is an essential mediator in health and disease. The gut microbiota interacts with various organs and systems in the body, including brain, lung, liver, bone, cardiovascular system, and others. Microbiota-derived metabolites such as the short chain fatty acid (SCFA) butyrate are primary signals, which link the gut microbiota and physiology. Recently, the gut microbiota has been identified as the origin of a number of diseases by influencing the related cell signaling pathways such as WNT/beta-catenin pathway in colorectal cancer and T cell receptor signaling in the central nervous system...

The colon rectal portion of gastrointestinal tract (GI) is full of microorganisms with different complex community that plays important role in maintaining homeostasis. But now-a-days different literature indicated that microbiota cause development of colorectal cancer (CRC) with a disease and ultimately aggravates to death. The mechanism inside the colo-rectal portion of GI tract is not fully well-known and bacterial contribution inside it is also fully unclear. Therefore, there is certain evidence trying a target about the unclear mechanism between intestinal microbiota and CRC...

Fermentation of undigested proteins in human gastrointestinal tract (gut) by the resident microbiota, a process called bacterial putrefaction, can sometimes disrupt the gut homeostasis. In this process, essential amino acids (e.g., histidine, tryptophan, etc.) that are required by the host may be utilized by the gut microbes. In addition, some of the products of putrefaction, like ammonia, putrescine, cresol, indole, phenol, etc., have been implicated in the disease pathogenesis of colorectal cancer (CRC). We have investigated bacterial putrefaction pathways that are known to be associated with such metabolites...

BACKGROUND: Colorectal cancer is a worldwide health problem. Despite growing evidence that members of the gut microbiota can drive tumorigenesis, little is known about what happens to it after treatment for an adenoma or carcinoma. This study tested the hypothesis that treatment for adenoma or carcinoma alters the abundance of bacterial populations associated with disease to those associated with a normal colon. We tested this hypothesis by sequencing the 16S rRNA genes in the feces of 67 individuals before and after treatment for adenoma (N = 22), advanced adenoma (N = 19), and carcinoma (N = 26)...

Emerging evidence points to a strong association between the gut microbiota and the risk, development and progression of gastrointestinal cancers such as colorectal cancer (CRC) and hepatocellular carcinoma (HCC). Bile acids, produced in the liver, are metabolized by enzymes derived from intestinal bacteria and are critically important for maintaining a healthy gut microbiota, balanced lipid and carbohydrate metabolism, insulin sensitivity and innate immunity. Given the complexity of bile acid signalling and the direct biochemical interactions between the gut microbiota and the host, a systems biology perspective is required to understand the liver-bile acid-microbiota axis and its role in gastrointestinal carcinogenesis to reverse the microbiota-mediated alterations in bile acid metabolism that occur in disease states...

BACKGROUND The aim of this study was to compare the microbiota community structure, assess differences in intestinal bacterial types, and identify metagenomic biomarkers for disparate stages of colorectal cancer formation. MATERIAL AND METHODS A total of 160 individuals were recruited: 61 cases with non-tumor colon were regarded as the normal group, 47 cases with histology-substantiated colorectal adenomas were regarded as the adenoma group, and 52 cases with invasive adenocarcinomas were regarded as the cancer group...

Fusobacterium nucleatum (Fn), a specific species of gut microbiota, has been suggested to be enriched in the microsatellite instability-high (MSI-H) molecular subtype of colorectal carcinomas (CRCs). However, the clinicopathologic and molecular factors that interact with Fn in MSI-H CRCs are poorly understood. In this study, 16S ribosomal RNA gene DNA sequence of Fn was quantitatively measured by real-time polymerase chain reaction in tumor DNA samples from a total of 160 surgically resected MSI-H CRC tissues...

BACKGROUND: While the role of the gut microbiome in inflammation and colorectal cancers has received much recent attention, there are few data to support an association between the oral microbiome and head and neck squamous cell carcinomas. Prior investigations have been limited to comparisons of microbiota obtained from surface swabs of the oral cavity. This study aims to identify microbiomic differences in paired tumor and non-tumor tissue samples in a large group of 121 patients with head and neck squamous cell carcinomas and correlate these differences with clinical-pathologic features...

Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death. Most cases of CRC are detected in Western countries, with its incidence increasing year by year. The probability of suffering from colorectal cancer is about 4%-5% and the risk for developing CRC is associated with personal features or habits such as age, chronic disease history and lifestyle. In this context, the gut microbiota has a relevant role, and dysbiosis situations can induce colonic carcinogenesis through a chronic inflammation mechanism...

Inflammation affects all stages of tumorigenesis. A key signaling pathway leading to acute and chronic inflammation is through activation of the caspase-1 inflammasome. Inflammasome complexes are assembled on activation of certain nucleotide-binding domain, leucine-rich repeat-containing proteins (NLR), AIM2-like receptors, or pyrin. Of these, NLRP1, NLRP3, NLRC4, NLRP6, and AIM2 influence the pathogenesis of cancer by modulating innate and adaptive immune responses, cell death, proliferation, and/or the gut microbiota...

Sporadic and inflammatory forms of colorectal cancer (CRC) account for more than 80% of cases. Recent publications have shown mechanistic evidence for the involvement of gut bacteria in the development of both CRC-forms. Whereas, colon and rectal cancer have been routinely studied together as CRC, increasing evidence show these to be distinct diseases. Also, the common use of fecal samples to study microbial communities may reflect disease state but possibly not the tumor microenvironment. We performed this study to evaluate differences in bacterial communities found in tissue samples of 18 rectal-cancer subjects when compared to 18 non-cancer controls...

The molecular biological mechanisms underlying the evolutionary biologic changes leading to carcinogenesis remain unclear. The main objective of our study was to explore the evolution of the microbiota community and molecules related with CRC in the dynamic transition from normal colon epithelium to premalignant adenoma with the aid of an 'adenoma-carcinoma sequence' mouse CRC model induced by DMH. We generated a modified mouse CRC model induced by DMH for DNA sequences, and characterized the molecular networks...

OBJECTIVES: Evidence suggests a possible role of Fusobacterium nucleatum in colorectal carcinogenesis, especially in right-sided proximal colorectum. Considering a change in bowel contents and microbiome from proximal to distal colorectal segments, we hypothesized that the proportion of colorectal carcinoma enriched with F. nucleatum might gradually increase along the bowel subsites from rectum to cecum. METHODS: A retrospective, cross-sectional analysis was conducted on 1,102 colon and rectal carcinomas in molecular pathological epidemiology databases of the Nurses' Health Study and the Health Professionals Follow-up Study...

Gastrointestinal (GI) cancers are the leading cause of mortality worldwide. These cancers are the end result of a complex interplay between gene and environment. Bacteria, parasites, and viruses have been implicated in some cancers. Recent data have put at focus the gut microbiome as the key player firing tumorigenesis. Experimental and human studies have provided evidence on the role of microbiota in cancer development. Although subject to changes in different settings such as antibiotic treatment, diet or lifestyle, our microbiome is quite stable and is capable of increasing susceptibility to cancer or decrease and halt its progression...

BACKGROUND: Adenomatous polyps are the most common precursor to colorectal cancer, the second leading cause of cancer-related death in the United States. We sought to learn more about early events of carcinogenesis by investigating shifts in the gut microbiota of patients with adenomas. METHODS: We analyzed 16S rRNA gene sequences from the fecal microbiota of patients with adenomas (n = 233) and without (n = 547). RESULTS: Multiple taxa were significantly more abundant in patients with adenomas, including Bilophila, Desulfovibrio, proinflammatory bacteria in the genus Mogibacterium, and multiple Bacteroidetes species...

The beneficial roles of probiotics in lowering the gastrointestinal inflammation and preventing colorectal cancer have been frequently demonstrated, but their immunomodulatory effects and mechanism in suppressing the growth of extraintestinal tumors remain unexplored. Here, we adopted a mouse model and metagenome sequencing to investigate the efficacy of probiotic feeding in controlling s.c. hepatocellular carcinoma (HCC) and the underlying mechanism suppressing the tumor progression. Our result demonstrated that Prohep, a novel probiotic mixture, slows down the tumor growth significantly and reduces the tumor size and weight by 40% compared with the control...

The human intestinal microbiome plays a major role in human health and diseases, including colorectal cancer. Colorectal carcinogenesis represents a heterogeneous process with a differing set of somatic molecular alterations, influenced by diet, environmental and microbial exposures, and host immunity. Fusobacterium species are part of the human oral and intestinal microbiota. Metagenomic analyses have shown an enrichment of Fusobacterium nucleatum (F. nucleatum) in colorectal carcinoma tissue. Using 511 colorectal carcinomas from Japanese patients, we assessed the presence of F...

Bile acids have emerged as important signaling molecules in the host, as they interact either locally or systemically with specific cellular receptors, in particular the farnesoid X receptor (FXR) and TGR5. These signaling functions influence systemic lipid and cholesterol metabolism, energy metabolism, immune homeostasis, and intestinal electrolyte balance. Through defined enzymatic activities, the gut microbiota can significantly modify the signaling properties of bile acids and therefore can have an impact upon host health...

AIM: To evaluate ATP-binding cassette (ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer (CRC) development. METHODS: Literature search was conducted on PubMed using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohn's disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein (P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2 (MRP2) and ABCG2/breast cancer resistance protein (BCRP), Abcb1/Mdr1a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function...

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in Japan. The etiology of CRC has been linked to numerous factors including genetic mutation, diet, life style, inflammation, and recently, the gut microbiota. However, CRC-associated gut microbiota is still largely unexamined. This study used terminal restriction fragment length polymorphism (T-RFLP) and next-generation sequencing (NGS) to analyze and compare gut microbiota of Japanese control subjects and Japanese patients with carcinoma in adenoma...