Examining the Role of Virulence Proteins From Pathogenic Anaerobes in the Initiation of Colorectal Cancer

Colorectal cancer (CRC) is a rising threat in modern populations, driven by reduced dietary fiber intake, pollution, poor hygiene, and especially the overuse of antibiotics. Anaerobe-induced CRC has emerged as a focal area in current research, with particular attention to anaerobic pathogenic bacteria such as Helicobacter pylori, Fusobacterium nucleatum, Solobacterium moorei, Bacteroides fragilis toxin (BFT), Peptostreptococcus anaerobius, and Parvimonas micra. Pathogens inhabit concerning niche within the gut, releasing virulence factors that disrupt gut microbiota homeostasis, leading to significant dysbiosis and chronic inflammation. Persistent inflammatory state activates various inflammatory markers, triggering cancer-associated signaling pathways. Moreover, bacterial toxins and biofilm formation exacerbate these effects by activating multiple malignant signaling pathways. Review explores recent advances in therapeutic strategies, emphasizing the importance of a deeper understanding of anaerobes and their pivotal roles in CRC progression. We highlight the major anaerobes likely to be classified as grade I carcinogens in the future and underscore the critical need for effective interventions to mitigate their impact on CRC development.