Correlation of Clinicopathological Features and IL6 Expression in Tumor Budding of Colon Adenocarcinoma

Background: Interleukin-6 (IL6) is one of the main cytokines produced by cancer-associated fibroblasts (CAFs). IL6 is linked with cancer progression and poor prognosis by activating cancer cells and modifying the cancer microenvironment. However, little is known about the expression of IL6 in tumor budding (TB) and its association with TB in colon adenocarcinoma (CA). Methods: The clinicopathological and prognostic significance of IL6 in TB was examined using a tissue microarray consisting of 36 patient samples of TB in CA. IL6 mRNA was detected by RNAscope kit. Patients were stratified into negative and positive IL6 expression groups.Results: IL6 expression was overwhelmingly observed in CAFs but was negligible in cancer cells. In the IL6-positive group in CAFs, TB grade was higher than in the IL6-negative group (P=0.0161). There was a significant difference in overall survival (OS) between CA cases in the IL6-positive group and the IL6-negative group (log rank test, P=0.0367). Cox proportional hazard regression model revealed that the IL6-negative group (OR = 0.25; 95% CI: 0.05–0.96; P=0.0440) had better OS for CA than the IL6-positive group. Conclusions: TB may be affected by IL6 expression, and IL6 expression in CAFs at TB may make IL6 an important prognostic marker.