The gut epithelium is a habitat of a variety of microorganisms, including bacteria, fungi, viruses and Archaea. With the advent of sophisticated molecular techniques and bioinformatics tools, more information on the composition and thus function of gut microbiota was revealed. The gut microbiota as an integral part of the intestinal barrier has been shown to be involved in shaping the mucosal innate and adaptive immune response and to provide protection against pathogens. Consequently, a set of biochemical signals exchanged within microbes and communication between the microbiota and the host have opened a new way of thinking about cancer biology. Probiotics are living organisms which administered in adequate amounts may bring health benefits and have the potential to be an integral part of the prevention/treatment strategies in clinical approaches. Here we provide a comprehensive review of data linking gut microbiota to cancer pathogenesis and its clinical course. We focus on gastrointestinal cancers, such as gastric, colorectal, pancreatic and liver cancer.

中文翻译：

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胃肠道癌症：微生物群在致癌作用中的作用以及益生菌和微生物群在抗癌治疗功效中的作用

肠道上皮是多种微生物的栖息地，包括细菌，真菌，病毒和古细菌。随着先进的分子技术和生物信息学工具的出现，人们发现了更多有关肠道菌群组成和功能的信息。肠道菌群作为肠道屏障的组成部分已被证明参与塑造粘膜固有的和适应性的免疫反应，并提供针对病原体的保护。因此，微生物内部交换的一系列生化信号以及微生物群与宿主之间的通讯开启了一种思考癌症生物学的新方法。益生菌是一种活生物体，以足够的量服用可能带来健康益处，并有可能成为临床方法中预防/治疗策略不可或缺的一部分。在这里，我们提供了将肠道菌群与癌症发病机理及其临床过程相关的数据的全面综述。我们专注于胃肠道癌，例如胃癌，大肠癌，胰腺癌和肝癌。