RRM2 Is a Putative Biomarker and Promotes Bladder Cancer Progression via PI3K/AKT/mTOR Pathway

Bladder cancer (BLCA) is the tenth most common cancer worldwide, characterized by its high recurrence and progression rates. Thus, identifying prognostic biomarkers and understanding its underlying mechanisms are imperative to enhance patient outcomes. In this study, we aimed to investigate the prognostic significance, expression, functional activity, and underlying mechanisms of RRM2 in BLCA. RRM2 expression and its association with pathological grading and survival were investigated in samples from TCGA dataset and BLCA tissue microarray. CCK8 assays, colony formation assays, wound healing, and transwell assays were performed to assess the role of RRM2 in BLCA cell proliferation and migration. Western blot was employed to investigate alterations in markers associated with epithelial-to-mesenchymal transition (EMT), apoptosis, and cell cycle regulation. Gene set enrichment analysis was performed to investigate the biological processes associated with RRM2, which were subsequently validated. The expression of RRM2 was significantly elevated in both BLCA tissues and cells. Our results also indicated a positive correlation between RRM2 expression and high tumor stage, high tumor grade, and poor survival. Knockdown of RRM2 inhibited cell proliferation and migration of BLCA. RRM2 knockdown significantly induced apoptosis and arrested the cell cycle at the G0/G1 phase. Opposite results were observed in the RRM2 overexpression cells. Additionally, our study demonstrates that RRM2 promotes BLCA progression by activating the PI3K/AKT/mTOR pathway. RRM2 is remarkably correlated with poor prognosis in BLCA and facilitate its progression via PI3K/AKT/mTOR pathway. It is suggested that RRM2 might become an effective prognostic biomarker and potential therapeutic target for BLCA.