Present in approximately 20 to 50% of colon tumors compared to less than 5% of normal tissue in CRC patients. Patients with high counts of S. gallolyticus have increased expression of proinflammatory cytokines, including interleukin-1 (IL-1) and cyclooxygenase-2 (COX-2). This evidence concerns the gene PTGS2 and colonic neoplasm.