TY - JOUR T1 - DNA Repair Protein Expression and Oxidative/Nitrosative Stress in Ulcerative Colitis and Sporadic Colorectal Cancer JF - Anticancer Research JO - Anticancer Res SP - 3261 LP - 3270 DO - 10.21873/anticanres.15112 VL - 41 IS - 7 AU - PAULA M. DE ANGELIS AU - LINDA DORG AU - SEAN PHAM AU - SOLVEIG NORHEIM ANDERSEN Y1 - 2021/07/01 UR - http://ar.iiarjournals.org/content/41/7/3261.abstract N2 - Background/Aim: Chronic inflammation generates large quantities of reactive oxygen and nitrogen species that damage DNA. DNA repair is important for cellular viability and genome integrity. Materials and Methods: Expression levels of the DNA repair proteins OGG1, XPA, MLH1, PARP1, and XRCC6, which function in base excision repair, nucleotide excision repair, mismatch repair, single-strand break repair and double-strand break repair, respectively, were assessed using immunohistochemistry in ulcerative colitis and sporadic colorectal cancer biopsies. Levels of oxidative/ nitrosative stress biomarkers were also assessed. Results: Ulcerative colitis and colorectal cancer lesions expressed significantly higher levels of all DNA repair proteins and oxidative/ nitrosative stress biomarkers compared to normal colonic mucosa. Ulcerative colitis had the highest XPA and XRCC6 expression. Conclusion: Oxidative/nitrosative stress is prevalent in the colon of both diseases. Nucleotide excision repair and non-homologous end-joining double-strand break repair may be compromised in colorectal cancer, but not in ulcerative colitis. ER -