Expression of Interleukin 23p19 in Colorectal Carcinoma: An Immunohistochemical Study with Clinico-Pathological Correlation

Abstract

Background Cancer of the colon is the fourth most common cancer in the world, while cancer of the rectum is the eight most common. Together, colorectal carcinomas (CRCs) are the third most commonly diagnosed form of cancer globally, comprising about 11% of all cancer diagnoses. In Egypt, a rapid increase in CRC incidence has been observed with an unusually high rate under the age of 40. Interleukin 23 (IL-23) is a member of a family of pro-inflammatory cytokines, consisting of a p19 subunit and a p40 subunit. Studies showed that IL-23 signaling causes up-regulation of MMP9, increased angiogenesis, and reduced CD8+ T cell recruitment to tumors. Therefore, IL-23–mediated inflammatory processes might provide a tumor-promoting microenvironment. Objective To evaluate the immunohistochemical expression of IL23p19 in colorectal carcinoma with clinico-pathological correlation. Methods This is a retrospective study consisting of formalin fixed paraffin embedded tissue blocks of 25 cases diagnosed as colorectal carcinoma. All tissue blocks were retrieved from the archives of the pathology department at Al-Demerdash Hospital. Results There was a significant difference between CRC cases with different tumor stages as regard total IL23p19 expression, as 100% of cases with higher stage (T4a/b) had positive expression compared to 42.9% and 92.9% of T2 and T3 respectively. However, no significant difference was detected between cases with different tumor grades as regard total IL23p19 expression. Conclusion It can be concluded from our study that there is an association between IL23p19 expression and the pathological stage in CRC patients. IL23p19 could be used as a prognostic biomarker and a potential treatment target.