Role and mechanism of lncRNA NALT1 in Erastin-induced ferroptosis in colorectal cancer cells

Objective To preliminarily investigate the role and mechanism by which long non-coding RNA (lncRNA) NALT1 interacts with the tumor suppressor protein p53 to promote Erastin-induced ferroptosis in human colorectal cancer (CRC) cells.

Methods The ferroptosis inducer Erastin was used to induce ferroptosis in RKO cells. Cell viability and sensitivity to cell death were assessed using flow cytometry and the cell counting kit-8 (CCK-8) assay. Quantitative real-time PCR (qPCR) was performed to detect intracellular NALT1 expression. Stable NALT1-overexpressing RKO cell lines and control cell lines were established via lentiviral transduction. The effect of NALT1 on Erastin-induced lipid peroxidation was further evaluated using flow cytometry and immunofluorescence. The intervention experiment with ferroptosis inhibitor Ferrostatin-1 (Fer-1) was used to assess the impact of NALT1 on cell viability, lipid peroxidation levels, and glutathione (GSH) content following Erastin treatment. RNA immunoprecipitation (RIP) assays were performed to detect the interaction between NALT1 and p53 protein. Additionally, flow cytometry and immunofluorescence were used to determine whether NALT1 overexpression could rescue the inhibition of Erastin-induced lipid peroxidation caused by p53 knockdown.

Results Erastin treatment significantly increased lipid peroxidation and decreased cell viability in RKO cells, enhancing sensitivity to ferroptosis, accompanied by significant upregulation of NALT1 expression (P < 0.05). NALT1 overexpression further amplified Erastin-induced lipid peroxidation and ferroptotic cell death (P < 0.05). Fer-1 treatment significantly alleviated Erastin-induced lipid peroxidation and cellular ferroptosis, and partially reversed the lipid peroxidation promoted by NALT1. In GSH assays, Fer-1 partially restored GSH levels in the control cells, but this effect was not significant in NALT1-overexpressing cells.

Conclusion NALT1 may promote ferroptosis by interacting with p53 to upregulate lipid peroxidation levels and enhance sensitivity to Erastin in CRC cells.