RESUMEN
Ferroptosis, a recently discovered type of programmed cell death triggered by excessive accumulation of irondependent lipid peroxidation, is linked to several malignancies, including nonsmall cell lung cancer. Long noncoding RNAs (lncRNAs) are involved in ferroptosis; however, data on their role and mechanism in cancer therapy remains limited. Therefore, the aim of the present study was to identify ferroptosisassociated mRNAs and lncRNAs in A549 lung cancer cells treated with RASselective lethal 3 (RSL3) and ferrostatin1 (Fer1) using RNA sequencing. The results demonstrated that lncRNA lung cancerassociated transcript 1 (LUCAT1) was significantly upregulated in lung adenocarcinoma and lung squamous cell carcinoma tissues. Coexpression analysis of differentially expressed mRNAs and lncRNAs suggested that LUCAT1 has a crucial role in ferroptosis. LUCAT1 expression was markedly elevated in A549 cells treated with RSL3, which was prevented by coincubation with Fer1. Functionally, overexpression of LUCAT1 facilitated cell proliferation and reduced the occurrence of ferroptosis induced by RSL3 and Erastin, while inhibition of LUCAT1 expression reduced cell proliferation and increased ferroptosis. Mechanistically, downregulation of LUCAT1 resulted in the downregulation of both GTP cyclohydrolase 1 (GCH1) and ferroptosis suppressor protein 1 (FSP1). Furthermore, inhibition of LUCAT1 expression upregulated microRNA (miR)34a5p and then downregulated GCH1. These results indicated that inhibition of LUCAT1 expression promoted ferroptosis by modulating the downregulation of GCH1, mediated by miR34a5p. Therefore, the combination of knocking down LUCAT1 expression with ferroptosis inducers may be a promising strategy for lung cancer treatment.
Asunto(s)
Regulación hacia Abajo , Ferroptosis , GTP Ciclohidrolasa , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Humanos , Ferroptosis/genética , MicroARNs/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Células A549 , GTP Ciclohidrolasa/genética , GTP Ciclohidrolasa/metabolismo , Proliferación Celular , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Masculino , Línea Celular Tumoral , Femenino , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/metabolismoRESUMEN
Hydroxyl radical (·OH) generated by the Fenton reaction between transition metal ions and hydrogen peroxide (H2O2) can induce significant cellular damage. However, the specific mechanism of ·OH-induced cell death has not been systematically studied. In this study, we reacted FeSO4 and Fe3O4 magnetic nanoparticles with H2O2 and found that ·OH generated from the intracellular Fenton reaction can lead to significant cell death. The Fenton reaction between Fe2+ with H2O2 resulted in a shift in lipid peroxidation and cell cycle arrest. It is noteworthy that the ·OH generated from the Fenton reaction triggered severe apoptosis but did not lead to DNA double-strand breakage. Our results suggest that the Fenton reaction had acute cytotoxicity, which was primarily due to ·OH produced from the Fenton reaction inducing lipid peroxidation and apoptosis and modulating the cell cycle, but not by inducing DNA damage.