Review Articles in 2011

The gut microbiota is now widely recognized to have a central role in human health and disease, and can be manipulated to improve an individual's health. Fecal microbiota transplantation (FMT), as outlined in this Review, is one such approach to resolve dysbiosis of the gut microbiota and has therapeutic potential in a range of gastrointestinal diseases. The authors provide a broad overview of FMT and a timely update on the latest advances.

Treating pancreatic cancer can be challenging, as patients often have a poor prognosis and chemoresistance is common. As pancreatic cancer is fundamentally a genetic disease, the authors of this Review emphasize the complex mutational heterogeneity of pancreatic ductal adenocarcinomas and the importance of moving towards a model of tailoring therapies to the specific genetic characteristics of individual tumors.

This Review describes interactions between intrahepatic cholangiocarcinoma cells and the surrounding stroma, with a focus on myofibroblastic cells. A 'human-like' orthotopic rat model and a new organotypic culture system have been developed, which can be used to test new therapies. Novel combination approaches to treatment that target both the cancer cells and cancer-promoting stromal cells are discussed.

Gastroesophageal reflux disease (GERD) is a chronic disorder that occurs when refluxate from the stomach comes into contact with the esophageal mucosa, typically causing symptoms such as heartburn and regurgitation. This Review focuses on the mucosal pathogenesis of GERD and describes new concepts in the role of mucosal inflammation in disease development in relation to the current model of GERD pathogenesis.

MRI could be used by clinicians as an effective tool to monitor patients with Crohn's disease. In this Review, Gionata Fiorino, Cristiana Bonifacio, Luca Balzarini, Alberto Malesci and Silvio Danese discuss the development of objective MRI-based scores that enable evaluation of the extent of intestinal damage. They also speculate on the generation of a new 'damage-driven' treatment paradigm—in which imaging is used to monitor intestinal damage and medication use is targeted to prevent the accumulation of further damage

Currently, vaccines are not widely used in the control of cholera, but new-generation orally administered vaccines may well become important tools in the public health armamentarium against this disease. This Review focuses on selected aspects of the disease, its pathogenesis and immunology, clinical features, epidemiology and treatment, and summarizes the status of new-generation cholera vaccines.

Over the past 10 years, most developed nation states have implemented mass population screening programs for colorectal cancer. Advances in the development of diagnostic molecular markers for colorectal cancer have yielded an expanding list of potential new screening modalities. The purpose of this Review is to summarize the different screening strategies that have been or are being investigated and to provide a critical evaluation of the performance data and relative merits of the potential new methods.

Hepatocellular carcinoma (HCC) is the third most common cause of death from cancer worldwide. In this Review Yan Li, Zhao-You Tang and Jin-Xuan Hou provide an overview of animal models that are relevant to HCC development, metastasis and treatment. Viral hepatitis is the single most important cause of HCC and the authors describe transgenic mouse models of HBV and HCV infection that have provided experimental evidence that viral genes could initiate or promote liver carcinogenesis. The criteria for establishing ideal HCC animal models are also discussed.

Campylobacter jejuniandC. coli are well-established human gastrointestinal pathogens, but other Campylobacterspecies (so-called emerging species) have also been shown to infect both humans and animals. In this Review, Man highlights the clinical importance of these emerging bacteria in both gastrointestinal and extragastrointestinal disease and describes the epidemiology, pathogenesis and transmission of these organisms.

Colorectal cancer (CRC) results from an accumulation of genetic and epigenetic changes in colon epithelial cells, which transforms them into adenocarcinomas. Over the past decade, major advances have been made in understanding cancer epigenetics, particularly regarding aberrant DNA methylation. Lao and Grady provide an overview of the role of epigenetics in CRC and discuss the clinical applications of these epigenetic alterations as biomarkers for early detection, diagnosis, prognostication and management of patients with CRC.

Gastrointestinal endoscopy has a central role in the evaluation and management of gastrointestinal diseases. This procedure during pregnancy, however, raises the unique issue of fetal safety. This Review addresses the need for cohesive information on endoscopic safety in pregnancy by comprehensively reviewing the subject and synthesizing practical clinical recommendations. The article aims to enable clinicians to make decisions on performing endoscopy, employ procedural modifications to enhance fetal safety, and to advise their pregnant patients about fetal risks.

The majority of patients with IBD use conventional therapy over a prolonged period of time to induce and maintain remission. In this Review, Kirstin Taylor and Peter Irving discuss the multiple ways in which conventional therapy can be optimized, such as by simplifying dosing regimens or adjusting drug dosage.

The prevalence of childhood and adolescent obesity is increasing. Although obesity is preventable, effective management in those individuals already affected is crucial as the condition is associated with serious long-term complications. Baur and colleagues address the assessment and management of obesity in children and adolescents, describing key features in the diagnosis, treatment and management of these patients.

Colonoscopy is an endoscopic procedure that allows the entire colon to be examined, enabling both the detection and removal of premalignant lesions and colorectal tumors. Hazewinkel and Dekker provide an overview of standard colonoscopy procedures and describe the latest technical advances. They stress the importance of a minimal set of quality indicators to continuously monitor and optimize colonoscopic examinations.

Over the past few decades, tremendous advances have been made in endoscopic technology, and the management of dysplasia and early cancer in Barrett esophagus has changed radically from being surgical to organ-sparing endoscopic therapy. Repaka and Chak discuss the vital role of endoscopy in the diagnosis, screening, surveillance and management of patients with Barrett esophagus.

Natural orifice transluminal endoscopic surgery (NOTES) has gained a great deal of attention since its introduction in 2000, and has opened up a realm of new endoscopic techniques, innovative endoscopic instruments, and pioneering treatment modalities. The field of NOTES has advanced tremendously and exciting and well-designed research has been reported. In this article, Khashab and Kalloo review recently published data, and provide their thoughts about how the field is progressing and what the next steps for NOTES should be.

The field of gastrointestinal endoscopy is undergoing some major advances. Numerous new endoscopic imaging techniques are now available. In this Review, the authors discuss the latest imaging technologies that have the potential to revolutionize endoscopic diagnosis and highlight the technical advances in the detection, characterization and confirmation of gastrointestinal disease.

This article by Zepeda-Gómez and Baron discusses the principles of endoscopic therapy for benign biliary strictures, different endoscopic approaches and their respective outcomes, and varied etiologies and their appropriate management. Data on newer therapies, such as the placement of self-expandable metal stents, and the treatment of biliary–enteric anastomotic strictures is also discussed.

The human gut supports a dense, diverse and dynamic bacterial ecosystem, which is important to intestinal health and disease. Quantitative and qualitative alterations to the intestinal microbiota are involved in many disease states. In this Review, the authors provide a broad overview of the importance of the intestinal microbiota in chronic disorders of the gut, including enteric infections, IBS, IBD and colorectal cancer.

Despite its high prevalence worldwide, alcoholic liver disease (ALD) has attracted little attention in the past two decades. Abstinence has been the most effective therapy, but targeted therapies are required for severe forms. Novel potential therapeutic targets have been identified, but their pathogenetic roles remain unknown. This Review summarizes the epidemiology, risk factors and current knowledge of ALD, including discussion of new therapeutic targets.