RESUMO
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.
Assuntos
Regulação para Baixo , Ferroptose , GTP Cicloidrolase , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , Ferroptose/genética , MicroRNAs/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Células A549 , GTP Cicloidrolase/genética , GTP Cicloidrolase/metabolismo , Proliferação de Células , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Masculino , Linhagem Celular Tumoral , Feminino , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismoRESUMO
Ionizing radiation (IR) induces severe hematopoietic injury by causing DNA and RNA damage as well as activating the immune responses, necessitating the development of effective therapeutic strategies. Ribonuclease L (RNase L) as an innate immune response pathway is triggered by exogenous and endogenous abnormal dsRNA under viral infection and dyshomeostasis, thereby activating the immune responses. Thus, we investigated the effect of RNase L on irradiation-induced bone marrow damage using RNase L knockout (RNase L-/-) mice. Phenotypic analysis revealed that RNase L knockout mitigates irradiation-induced injury in the bone marrow. Further investigation into the mechanism of RNase L by RNA-seq, qRT-PCR, and CBA analysis demonstrated that RNase L deficiency counteracts the upregulation of genes related to immune responses induced by irradiation, including cytokines and interferon-stimulated genes. Moreover, RNase L deficiency inhibits the increased levels of immunoglobulins in serum induced by irradiation. These findings indicate that RNase L plays a role in the immune response induced by irradiation in the bone marrow. This study further enhances our understanding of the biological functions of RNase L in the immune response induced by irradiation and offers a novel approach for managing irradiation-induced bone marrow injury through the regulation of RNase L activation.
