Potential carcinogenic role of Reg IV in ulcerative colitis-associated colorectal neoplasia.

Background: Early detection of ulcerative colitis-associated neoplasia (UC-N) remains a clinical challenge. Identification of molecular biomarkers for colorectal dysplasia and cancer may be extremely beneficial in early detection and managing cancer risk in long-standing ulcerative colitis (UC) patients.

Objective: The aim of this work is to investigate the role of Reg IV in comparison to P53 and KRAS in UC-associated dysplasia and colorectal cancer (CRC) in order to evaluate the potential use of Reg IV for dysplasia and cancer screening in UC patients.

Methods: The study was conducted on 5 groups each 20 colonic endoscopic samples: 1) Normal colonic mucosa, 2) Active UC without dysplasia/carcinoma, 3) UC-associated dysplasia, 4) UC-associated CRC (UC-CRC), 5) Sporadic CRC. All included cases were subjected to Reg IV mRNA expression analysis by quantitative reverse transcription polymerase chain reaction, and immunostaining for Reg IV, P53 and KRAS.

Results: Reg IV mRNA expression levels were found to be significantly higher in groups 3 and 4 (mean: 3.37 and 5.70, respectively). Reg IV immunostaining was highly expressed in groups 3 and 4 (mean: 45.80 and 62.35, respectively). While P53 and KRAS immunostaining was highly expressed in group 5 (mean: 64.57 and 62.90). Furthermore, Reg IV immunoexpression had shown a negative correlation with P53 and KRAS immunoexpression in groups 4 and 5.

Conclusion: Higher expression of Reg IV in patients with UC-dysplasia and UC-CRC versus KRAS and P53 expression in sporadic CRC, suggests a potential role of Reg IV in UC carcinogenesis pathway. This could advocate the use of Reg IV as a screening biomarker for UC-N among patients with long-standing UC as well as a promising targeted therapeutic strategy.