Colorectal cancer: the facts in the case of the microbiota.
Clay Slater L,Fonseca-Pereira Diogo,Garrett Wendy S
The Journal of clinical investigation
The importance of the microbiota in the development of colorectal cancer (CRC) is increasingly evident, but identifying specific microbial features that influence CRC initiation and progression remains a central task for investigators. Studies determining the microbial mechanisms that directly contribute to CRC development or progression are revealing bacterial factors such as toxins that contribute to colorectal carcinogenesis. However, even when investigators have identified bacteria that express toxins, questions remain about the host determinants of a toxin's cancer-potentiating effects. For other cancer-correlating bacteria that lack toxins, the challenge is to define cancer-relevant virulence factors. Herein, we evaluate three CRC-correlating bacteria, colibactin-producing Escherichia coli, enterotoxigenic Bacteroides fragilis, and Fusobacterium nucleatum, for their virulence features relevant to CRC. We also consider the beneficial bioactivity of gut microbes by highlighting a microbial metabolite that may enhance CRC antitumor immunity. In doing so, we aim to elucidate unique and shared mechanisms underlying the microbiota's contributions to CRC and to accelerate investigation from target validation to CRC therapeutic discovery.
The Role of Intestinal Microbiota in Colorectal Cancer.
Ren Lingli,Ye Juan,Zhao Bing,Sun Jinbing,Cao Peng,Yang Yang
Frontiers in pharmacology
Colorectal cancer is a multifactorial disease involving genetic, environmental, and lifestyle risk factors. Intestinal microbiota plays an important role in the occurrence and development of colorectal cancer. Studies have shown that the behavior of intestinal microbiota can lead to pathological changes in the host intestine, which can be divided into epigenetic changes and carcinogenic changes at the gene level, and ultimately promote the formation and development of colorectal cancer. Intestinal microbiota is mainly distributed in the intestinal epithelium, which is composed of a large number of microorganisms interacting with the host intestinal cells. It can affect the immune-inflammation and metabolism of the gastrointestinal tract, and may be used as a biomarker for disease diagnosis. Regulation of gut microbiota is a promising strategy for the prevention and treatment of colorectal cancer. This article reviews the role of intestinal microbiota in the development of colorectal cancer, including the related mechanisms of intestinal microbiota promoting colorectal cancer, the use of intestinal microbiota in the diagnosis of colorectal cancer, and the regulation of intestinal microbiota in the prevention or treatment of colorectal cancer.
The Intestinal Microbiota and Colorectal Cancer.
Cheng Yiwen,Ling Zongxin,Li Lanjuan
Frontiers in immunology
The intestinal microbiota, composed of a large population of microorganisms, is often considered a "forgotten organ" in human health and diseases. Increasing evidence indicates that dysbiosis of the intestinal microbiota is closely related to colorectal cancer (CRC). The roles for intestinal microorganisms that initiated and facilitated the CRC process are becoming increasingly clear. Hypothesis models have been proposed to illustrate the complex relationship between the intestinal microbiota and CRC. Recent studies have identified , enterotoxigenic , , , , and as CRC candidate pathogens. In this review, we summarized the mechanisms involved in microbiota-related colorectal carcinogenesis, including inflammation, pathogenic bacteria, and their virulence factors, genotoxins, oxidative stress, bacterial metabolites, and biofilm. We also described the clinical values of intestinal microbiota and novel strategies for preventing and treating CRC.
The Intestinal Microbiota in Colorectal Cancer.
Tilg Herbert,Adolph Timon E,Gerner Romana R,Moschen Alexander R
Experimental evidence from the past years highlights a key role for the intestinal microbiota in inflammatory and malignant gastrointestinal diseases. Diet exhibits a strong impact on microbial composition and provides risk for developing colorectal carcinoma (CRC). Large metagenomic studies in human CRC associated microbiome signatures with the colorectal adenoma-carcinoma sequence, suggesting a fundamental role of the intestinal microbiota in the evolution of gastrointestinal malignancy. Basic science established a critical function for the intestinal microbiota in promoting tumorigenesis. Further studies are needed to decipher the mechanisms of tumor promotion and microbial co-evolution in CRC, which may be exploited therapeutically in the future.