Differential Abundance Analysis of Gut Microbiome between Healthy Controls and Colorectal Cancer Patients

Colorectal cancer (CRC) is a significant public health burden, accounting for approximately 10% of all new cancer cases worldwide, making it the world’s third most deadly cancer. The causes of CRC are complex and environmental factors play a stronger role than genetic factors. The gut microbiome has been linked to several bowel cancers, such as CRC. The present study aimed to estimate differential abundance analysis of CRC versus HC groups of the colorectal microbiome. Biopsy samples were taken from the normal mucosa of 13 healthy controls (HC) and the tumor of 17 patients with CRC during colonoscopy. The microbiome of tumor tissue and normal mucosa was evaluated by 16S rRNA gene amplicon sequencing. Differential abundance analysis of CRC versus HC groups showed that Enterobacteriaceae, Bacteroides fragilis, Prevotella, Fusobacterium, Leptotrichia, Akkermansia muciniphila, Streptococcus, and Parabacteroides have drastic fold changes (P ≤ 0.05). A heat map and dendrogram of the 20 ascending operational taxonomic units (OTUs) based on the FDR (False Discovery Rate) p-value were constructed to visualize the similarity between CRC and HC samples. The significant difference in the differential abundance of bacteria taxa in CRC versus HC groups indicates that these bacteria can be important pathogens in the development and progression of CRC.