Microbial Biofilms, Colorectal Inflammation and Cancer

Review Article

Austin J Gastroenterol. 2016; 3(1): 1059.

Microbial Biofilms, Colorectal Inflammation and Cancer

Chen Y, Peng Y* and Fu X*

Department of Gastroenterology, Affiliated Hospital of Southwest Medical University, China

*Corresponding author: Yan Peng, Department of Gastroenterology, Affiliated Hospital of Southwest Medical University, Street Taiping 25#, Region Jiangyang, Sichuan, China

Xiangsheng Fu, Department of Gastroenterology, Affiliated Hospital of Southwest Medical University, Street Taiping 25#, Region Jiangyang, Sichuan, China

Received: March 17, 2016; Accepted: May 10, 2016; Published: May 12, 2016

Abstract

The human gastrointestinal tract is colonized throughout its length by complex luminal and mucosal microbiota. Recently, there has been an upsurge in interest in the role of microbial communities that occur in biofilms on surfaces in the gut. Owing to their proximity to host tissues, mucosal bacteria interact more readily with the gut epithelium and immune system than their luminal counterparts, and recent researches indicate that they play an important role in the pathogenesis of the colorectal tumors. In this review, we will illustrate the association between microbial biofilms and epithelial cells, inflammation and carcinogenesis of the colorectum. Progress in the management of microbial biofilms is also illustrated.

Keywords: Biofilms; Epithelial cells; Colorectal inflammation; Colorectal tumors

Introduction

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and accounts for approximately 132,700 new cases and 49,700 deaths in the United States in 2015 [1]. Almost 55% of the CRC cases occur in more developed regions. The mortality of CRC is considerably lower (8.5% of the total) with more deaths (52%) in less developed regions of the world [2]. In the industrialized nations, the lifetime risk of developing CRCs is about 5%, and developing an adenoma, a non-cancerous colon tumor that can develop into CRCs, is 20% [3]. The human intestinal tract is colonized approximately 1014 CFU/g of microbiota. In recent years, it has been found that gut microbiota (including S. gallolyticus, E. Faecalis, Enterotoxigenic Bacteroides fragilis, F. nucleatum) is closely related to the occurrence of CRCs [3-7]. The colon mucosa is covered by a mucus layer that segregates the microbiota from the host colonic epithelium. Breaches of this protective mucus layer will lead to increased contact between mucosal microbiota and the colonic epithelial cells. Concomitant with increased access to the mucosal epithelium, microbial community communication, microbial metabolism, microbial structure and function are modified and often resulting in biofilm formation [8,9] (Figure 1). The direct contact of biofilms with epithelial cells results in perturbed epithelial metabolism and function, and facilitates chronic inflammation and even CRCs [8]. Compared with left-sided CRC, right-sided colon tumor has unique biological behavior (the “two-colon” concept) [10]. A recent study found that gut bacteria biofilm is widespread in the right-side colon tumors [11]. However, the role of biofilms in the carcinogenesis of CRC is still not clarified. The possible mechanism may include epithelial cell damage, DNA damage, chronic inflammation and bacteria carcinogens, etc.

Citation: Chen Y, Peng Y and Fu X. Microbial Biofilms, Colorectal Inflammation and Cancer. Austin J Gastroenterol. 2016; 3(1): 1059. ISSN : 2381-9219