IDDF2019-ABS-0300 Dysbiosis of gut fungal microbiota in colorectal cancer: an assessment from faecal microbiome secretome

Abstract

Background Fungal microbiota may play important roles in maintaining human gut health but to date, the available data are scarce. The intricate crosstalks between these microbiotas and host possibly via protein secretions may contribute to the pathophysiology of Colorectal Cancer (CRC). Therefore, we aim to identify the faecal fungal secretome in patients with CRC-stricken gut. Methods Faecal samples from 26 clinically-diagnosed patients with CRC and 20 non-CRC control individuals were collected, homogenized and filtered followed by protein extraction and profiling by quantitative label-free proteomics using Nano-Liquid Chromatography TripleTOF Mass Spectrometry. The mass spectra datasets were searched using MaxQuant against the fungi’s Uniprot Fasta databases. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) version 22. Fungal taxa associated with clinical parameters were identified using multivariate association with linear models. Results We identified 570 fungal proteins secreted into the human gut. A distinct alteration in the diversity and composition of the fungal microbiota was observed in the CRC, with tremendous reductions of the overall fungal proteins, the diversity and composition of fungal microbiota as compared to the control (p Conclusions The distinct alteration of fungal proteins observed in CRC may suggest a possible CRC-specific gut microenvironment for fungi. This knowledge may be exploited for new therapeutic approaches for gut-related issues.