INTRODUCTION: Pathogenic strains of Escherichia coli have been clearly identified as the causative agents of extraintestinal and diarrheal infections; however, the etiopathogenic role of E. coli in other conditions, including colorectal cancer, remains unclear. METHODS: This study aimed to characterize mucosal E. coli isolates (n = 246) from 61 neoplasia patients and 20 healthy controls for the presence of 35 genetic determinants encoding known virulence factors. RESULTS: Virulence determinants encoding invasin (ibeA), siderophore receptor (iroN), S-fimbriae (sfa), and genotoxin (usp) were more prevalent among E. coli isolated from patients with neoplasia compared to the control group (p < 0.05). In addition, the prevalence of these virulence determinants was increased in more advanced neoplasia stages (p adj < 0.0125). Compared to patients with advanced colorectal adenoma and carcinoma, the ibeA gene was rarely found in the control group and among patients with non-advanced adenoma (p < 0.05), indicating its potential as the advanced-neoplasia biomarker. Patients with neoplasia frequently had E. coli strains with at least one of the abovementioned virulence factors, whereby specific combinations of these virulence factors were found. DISCUSSION: These findings suggest that E. coli strains isolated from patients with colorectal neoplasia possess several virulence factors, which could contribute to the development of neoplastic processes in the large intestine.

• Keywords
• Escherichia coli, cancer, colorectal neoplasia, genotoxin, ibeA, invasion, virulence factors,
• Publication type
• Journal Article MeSH

S100 proteins are involved in the pathogenesis of sporadic colorectal carcinoma through different mechanisms. The aim of our study was to assess tissue mRNA encoding S100 proteins in patients with non-advanced and advanced colorectal adenoma. Mucosal biopsies were taken from the caecum, transverse colon and rectum during diagnostic and/or therapeutic colonoscopy. Another biopsy was obtained from adenomatous tissue in the advanced adenoma group. The tissue mRNA for each S100 protein (S100A4, S100A6, S100A8, S100A9, S100A11 and S100P) was investigated. Eighteen biopsies were obtained from the healthy mucosa in controls and the non-advanced adenoma group (six individuals in each group) and thirty biopsies in the advanced adenoma group (ten patients). Nine biopsies were obtained from advanced adenoma tissue (9/10 patients). Significant differences in mRNA investigated in the healthy mucosa were identified between (1) controls and the advanced adenoma group for S100A6 (p = 0.012), (2) controls and the non-advanced adenoma group for S100A8 (p = 0.033) and (3) controls and the advanced adenoma group for S100A11 (p = 0.005). In the advanced adenoma group, differences between the healthy mucosa and adenomatous tissue were found in S100A6 (p = 0.002), S100A8 (p = 0.002), S100A9 (p = 0.021) and S100A11 (p = 0.029). Abnormal mRNA expression for different S100 proteins was identified in the pathological adenomatous tissue as well as in the morphologically normal large intestinal mucosa.

• Keywords
• S100 proteins, colorectal neoplasia, large intestine, mRNA,
• MeSH
• Adenoma genetics   metabolism   pathology   MeSH
• Calgranulin A genetics   metabolism   MeSH
• Calgranulin B genetics   metabolism   MeSH
• Colorectal Neoplasms genetics   metabolism   pathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• RNA, Messenger genetics   metabolism   MeSH
• Biomarkers, Tumor genetics   metabolism   MeSH
• Neoplasm Proteins genetics   metabolism   MeSH
• Follow-Up Studies MeSH
• Pilot Projects MeSH
• Prognosis MeSH
• S100 Calcium Binding Protein A6 genetics   metabolism   MeSH
• Cell Cycle Proteins genetics   metabolism   MeSH
• S100 Proteins genetics   metabolism   MeSH
• Calcium-Binding Proteins genetics   metabolism   MeSH
• S100 Calcium-Binding Protein A4 genetics   metabolism   MeSH
• Aged MeSH
• Case-Control Studies MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Calgranulin A MeSH
• Calgranulin B MeSH
• RNA, Messenger MeSH
• Biomarkers, Tumor MeSH
• Neoplasm Proteins MeSH
• S100 Calcium Binding Protein A6 MeSH
• Cell Cycle Proteins MeSH
• S100 Proteins MeSH
• Calcium-Binding Proteins MeSH
• S100 Calcium-Binding Protein A4 MeSH
• S100A11 protein, human MeSH Browser
• S100A4 protein, human MeSH Browser
• S100A6 protein, human MeSH Browser
• S100A8 protein, human MeSH Browser
• S100A9 protein, human MeSH Browser
• S100P protein, human MeSH Browser