Assessment of the Changes in Mitochondrial Gene Polymorphism in Ulcerative Colitis and the Etiology of Ulcerative Colitis-associated Colorectal Cancer

Background: Mitochondria are energy-producing organelles, and dysfunction in these organelles causes various types of disease. Although several studies have identified mutations in nuclear DNA that are associated with the etiology of ulcerative colitis (UC), information regarding mitochondrial DNA (mtDNA) in UC is limited. This study aimed to investigate the mitochondrial DNA polymorphism underlying the etiology of UC and UC-associated colorectal cancer. Materials and Methods: Next-generation sequencing was performed to assess mitochondrial DNA mutations in 12 patients with UC-associated cancer. The mtDNA mutations in the non- neoplastic mucosa, tumor tissues, and healthy controls were compared. Results: The incidence of mutations of nicotinamide adenine dinucleotide phosphate ubiquinone oxidase subunit, ATP synthetase, and tRNA was higher in non-neoplastic mucosa in those with UC compared with the healthy controls. However, no statistically significant differences were observed in mutations between the tumor tissues and non-neoplastic mucosa in UC. Conclusion: Significant mutations in mtDNA were observed in the nonneoplastic mucosa of patients with UC-associated cancer.