NUPR1 and LCN2: Potential Therapeutic Targets for Colorectal Cancer Via Modulating Cell Viability, Migration, and Ferroptosis-Related Pathways.

Nuclear protein 1 (NUPR1) is a small, highly basic transcriptional regulator that is involved in regulating a variety of cellular processes. However, its role in colorectal cancer (CRC) remains uncertain. This study aimed to elucidate the NUPR1 role in CRC progression and to explore its downstream mechanism. Cell viability, migration and invasive capabilities were detected using cell counting kit-8 and Transwell assays. The Iron content, malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), and lipid peroxidation were measured using assay kits. The interaction between NUPR1 and lipocalin 2 (LCN2) was examined by co-immunoprecipitation (Co-IP) and dual-luciferase reporter assays. BALB/c nude mice were used to establish xenograft models, tumor weight and volume were systematically recorded. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to quantify gene expression levels in both cellular and tumor tissue samples. Our results indicated that NUPR1 and LCN2 were significantly overexpressed in CRC cell lines. NUPR1 and LCN2 knockdown led to a significant reduction in cell viability and a decrease in both migratory and invasive capacity. The effects of NUPR1 knockdown on GSH, ROS, lipid peroxidation, iron, and MDA levels were comparable to those observed after erastin treatment. Moreover, the administration of ferrostatin-1 partially alleviated the effects of NUPR1 overexpression. Dual-luciferase reporter and Co-IP assays have demonstrated a direct interaction between NUPR1 and LCN2. In vivo experiments indicated that NUPR1 and LCN2 knockdown inhibited tumor growth, whereas NUPR1 overexpression facilitated tumor progression. NUPR1 and LCN2 knockdown resulted in increased acyl-CoA synthetase long-chain family member 4 (ACSL4) levels and a decrease in glutathione peroxidase 4 (GPX4) expression. Notably, the effects of NUPR1 overexpression were partially reversed by the LCN2 knockdown. These findings suggest a significant association between NUPR1 and LCN2, indicating that NUPR1 may serve as a potential therapeutic target for CRC treatment.