Letter to the Editor
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 28, 2024; 30(36): 4078-4082
Published online Sep 28, 2024. doi: 10.3748/wjg.v30.i36.4078
Beyond bacteria: Role of non-bacterial gut microbiota species in inflammatory bowel disease and colorectal cancer progression
Hania Haque, Syeda Warisha Zehra, Mohammad Shahzaib, Saif Abbas, Nazish Jaffar
Hania Haque, Syeda Warisha Zehra, Mohammad Shahzaib, Saif Abbas, Department of Medicine, Jinnah Sindh Medical University, Karachi 75510, Sindh, Pakistan
Nazish Jaffar, Department of Pathology, Jinnah Sindh Medical University, Karachi 75510, Sindh, Pakistan
Author contributions: Haque H and Zehra SW analyzed the literature and wrote the letter; Shahzaib M and Abbas S conducted relevant literature search; Shahzaib M proposed the idea; Jaffar N guided us through the process; All authors have read and approved the final manuscript.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Hania Haque, MBBS, Doctor, Department of Medicine, Jinnah Sindh Medical University, Rafiqui HJ, Iqbal Shaheed Road, Karachi Cantonment, Karachi 75510, Sindh, Pakistan. haniahaque2002@gmail.com
Received: June 9, 2024
Revised: August 11, 2024
Accepted: September 6, 2024
Published online: September 28, 2024
Processing time: 102 Days and 21.2 Hours
Abstract

This letter emphasizes the need to expand discussions on gut microbiome’s role in inflammatory bowel disease (IBD) and colorectal cancer (CRC) by including the often-overlooked non-bacterial components of the human gut flora. It highlights how viral, fungal and archaeal inhabitants of the gut respond towards gut dys-biosis and contribute to disease progression. Viruses such as bacteriophages target certain bacterial species and modulate the immune system. Other viruses found associated include Epstein-Barr virus, human papillomavirus, John Cunningham virus, cytomegalovirus, and human herpes simplex virus type 6. Fungi such as Candida albicans and Malassezia contribute by forming tissue-invasive filaments and producing inflammatory cytokines, respectively. Archaea, mainly metha-nogens are also found altering the microbial fermentation pathways. This corres-pondence, thus underscores the significance of considering the pathological and physiological mechanisms of the entire spectrum of the gut microbiota to develop effective therapeutic interventions for both IBD and CRC.

Keywords: Gut microbiota; Colorectal cancer; Inflammatory bowel disease; Dysbiosis; Bacteriophages; Methanogens; Fungi

Core Tip: This letter to the editor intends to contribute to the conversation surrounding the role of gut microbiota in the progression of conditions such as inflammatory bowel disease and colorectal cancer. The letter emphasizes the importance of recognizing microbial components beyond bacteria that also play a significant role in the pathogenesis of these diseases, along with encouraging further studies in this area to better understand the role of viruses, fungi and archaea.