SSBP1 positively regulates RRM2, affecting epithelial mesenchymal transition and cell cycle arrest in human lung adenocarcinoma cells

Abstract

Progression of lung adenocarcinoma (LUAD) is frequently associated with alterations in epithelial-mesenchymal transition (EMT) and cell cycle. Our study analyzed the Cancer Genome Atlas (TCGA) database and identified a positive correlation between high expression of SSBP1 in LUAD tumor tissues and poor prognosis (p < 0.05), with an AUC of 0.853, suggesting that SSBP1 could serve as a prognostic biomarker. In vitro experiments, including siRNA-mediated SSBP1 knockdown and subsequent cell cloning and Transwell assays, revealed significant inhibition of proliferation, migration, and cell cycle progression in LUAD cells (p < 0.05). In vivo mouse model experiments further confirmed that SSBP1 knockdown inhibits tumor burden (p < 0.05). Mechanistic investigations, integrating pathway enrichment analysis with molecular biology techniques, identified RRM2 as a downstream target of SSBP1, and RRM2 knockdown similarly suppressed LUAD cell proliferation, migration, and cell cycle progression (p < 0.05). These findings indicate that SSBP1 promotes EMT and cell cycle progression in LUAD cells by positively regulating RRM2, thereby accelerating disease progression. Collectively, our study not only confirms the potential role of SSBP1 in LUAD but also provides a theoretical foundation for therapeutic strategies targeting the SSBP1/RRM2 axis, potentially offering new therapeutic targets for LUAD patients.