IL‑23 concentration‑dependently regulates T24 cell proliferation, migration and invasion and is associated with prognosis in patients with bladder cancer.

Interleukin‑23 (IL‑23, also known as IL23A), is an important proinflammatory cytokine whose role in the development and progression of tumors remains controversial. The present study on IL‑23 focused on its impact on the tumor microenvironment. Existing studies on its direct role on tumor cells are limited. Previously, we reported that the expression level of IL‑23 in human bladder urothelial carcinoma was significantly higher than that in adjacent tissues as determined by immunohistochemistry. In this study, we further validated the results of immunohistochemistry using the Oncomine database and we found that IL23A expression in non‑muscle invasive bladder urothelial carcinoma (NMIBC) was significantly higher than that in muscle invasive bladder urothelial carcinoma (MIBC). Expression of IL23A was negatively correlated with the clinical stage of bladder urothelial carcinoma and had a positive correlation with prognosis. In vitro experiments revealed that different concentrations of IL‑23 had different effects on T24 cells. A low concentration of 20 ng/ml IL‑23 promoted T24 cell proliferation, migration, invasion and EMT transformation, while a high concentration of 40 ng/ml IL‑23 inhibited these functions. These results indicated that IL‑23 plays a dual role in the progression of bladder cancer. Low concentrations of IL‑23 promote bladder tumor progression, while high concentrations of IL‑23 have the opposite effect.