Decoding the Microbiota Whisper: Bacteroides fragilis Toxin Subtypes and Their IL-8 Signatures in Colorectal Oncogenesis

Abstract

Alterations in the gut microbiome balance could contribute to intestinal pathologies, including Colorectal Cancer (CRC). This research aims to investigate the relationship between Bacteroides. fragilis toxin variants and interleukin-8 (IL-8) expression in CRC patients. The study recruited 52 patients divided into two groups: 37 neoplastic (benign or malignant) and 15 non-neoplastic. Three biopsy samples were obtained. DNA was extracted from the first sample to determine the prevalence of B. fragilis toxin in the patients. The second sample was used for RNA extraction to detect IL-8 expression alongside Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which served as the housekeeping gene. The relative expression levels of IL-8 between cases and controls were compared. The third sample was sent to the Pathology department. Female patients with neoplastic illnesses showed a higher prevalence (56.8%) than males (43.2%). Neoplastic patients were significantly older than non-neoplastic patients. The study revealed a higher concentration of B. fragilis in neoplastic patients. Notably, patients with neoplastic conditions exhibited a significantly higher frequency of B. fragilis toxin (BFT). Analysis of IL-8 expression demonstrated a statistically significant difference between CRC patients and the non-neoplastic group. This marked variation between the two groups suggests a potential association between B. fragilis presence, its toxin, and the inflammatory response, as indicated by IL-8 expression in the context of CRC. This research provides insights into the complex interplay between specific bacterial toxins and inflammatory responses in the CRC, which could potentially contribute to the development of novel diagnostic markers or therapeutic strategies for CRC.