Background and Aim: Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype of esophageal cancer worldwide. Patients with ESCC display an altered esophageal microbiota compared with healthy individuals; however, little is known about the gut microbiota in ESCC. Methods: Here, we characterized the fecal microbiota of 15 ESCC patients and 16 healthy control subjects using 16S rRNA gene sequencing.Results: After controlling for potential confounders, significant alterations in both taxonomic and functional composition of the gut microbiota in ESCC patients were observed. By contrast, alpha diversity of the gut microbiota did not significantly differ between the cases and controls. We observed an enrichment of potentially pro-inflammatory and/or carcinogenic bacteria, such as Butyricimonas, Veillonella, and Streptococcus, and a depletion of butyrate-producing and/or potentially anti-inflammatory bacteria, such as Butyricicoccus, Lachnospiraceae NK4A136 group, and Eubacterium eligens group, in the gut microbiota of ESCC patients. The log-ratios of Streptococcus to Butyricicoccus and Streptococcus to Lachnospiraceae NK4A136 group of the gut microbiota were identified as potential diagnostic biomarkers for ESCC, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.863 (95% confidence interval: 0.707-1.000) and 0.825 (0.673-0.977), respectively. The diagnostic performance of both microbial biomarkers was validated in another ESCC cohort. Conclusions: This pilot study has revealed an altered gut microbiota in ESCC patients and has paved the way for large-scale prospective cohort studies to examine the causative relationship between ESCC and gut dysbiosis.recruited study subjects; MKC performed the experiments and data analysis, and drafted the manuscript; GGLY coordinated the project; PWYC and CBSL acquired funding for the project; CBSL supervised the project; SCN, HCY, HSK, PWYC and CBSL critically revised the manuscript. All authors approved the final version of the manuscript.

The use of probiotics to improve health via the modulation of gut microbiota has gained wide attention. The growing volume of investigations of probiotic microorganisms and commercialized probiotic products has created the need for a database to organize the health-promoting functions driven by probiotics reported in academic articles, clinical trials and patents. We constructed ProBioQuest to collect up-to-date literature related to probiotics from PubMed.gov, ClinicalTrials.gov and PatentsView. More than 2.8 million articles have been collected. Automated information technology-assisted procedures enabled us to collect the data continuously, providing the most up-to-date information. Statistical functions and semantic analyses are provided on the website as an advanced search engine, which contributes to the semantic tool of this database for information search and analyses. The semantic analytical output provides categorized search results and functions to enhance further analysis. A keyword bank is included which can display multiple tables of contents. Users can select keywords from different displayed categories to achieve easily filtered searches. Additional information on the searched items can be browsed via the link-out function. ProBioQuest is not only useful to scientists and health professionals but also to dietary supplement manufacturers and the general public. In this paper, the method we used to build this database-web system is described. Applications of ProBioQuest for several literature-based analyses of probiotics are included as examples of the various uses of this search engine. ProBioQuest can be accessed free of charge at http://kwanlab.bio.cuhk.edu.hk/PBQ/. Database URL: http://kwanlab.bio.cuhk.edu.hk/PBQ/

The use of probiotics to improve health via the modulation of gut microbiota has gained wide attention. The growing volume of investigations of probiotic microorganisms and commercialized probiotic products has created the need for a database to organize the health-promoting functions driven by probiotics reported in academic articles, clinical trials, and patents. Currently, no such database is available. We constructed ProBioQuest to collect up-to-date literature related to probiotics from PubMed.gov, ClinicalTrials.gov, and PatentsView. More than 2.8 million articles were collected by the end of 2021: PubMed.gov: 2 656 818; Clinical Trials.gov: 205 349; PatentsView: 32 536. Automated information technology-assisted procedures enabled us to collect the data continuously, providing the most up-to-date information. Statistical functions and semantic analyses are provided on the website as an advanced search engine, which contributes to the semantic tool of this database for information search and analyses. The semantic analytical output provides categorised search results and functions to enhance further analysis. A keyword bank is included which can display multiple tables of contents. Users can select keywords from different displayed categories to achieve easy filtered searches. Additional information on the searched items can be browsed via the link-out function. ProBioQuest is not only useful to scientists and health professionals, but also to dietary supplement manufacturers and the general public. In this paper, the method we used to build this database-web system is described. Applications of ProBioQuest for several literature-based analyses of probiotics are included as examples of the various uses to which this search engine can be put. ProBioQuest can be accessed free of charge at http://kwanlab.bio.cuhk.edu.hk/PBQ/. Database URL: http://kwanlab.bio.cuhk.edu.hk/PBQ/