Internal Medicine Department of Oncology, Jinjiang Municipal Hospital, Jinjiang, China.
J Biochem Mol Toxicol. 2024 Nov;38(11):e70015. doi: 10.1002/jbt.70015.
Lung adenocarcinoma (LUAD) emerges as one of the most lethal malignant tumors worldwide. Platinum-based combination chemotherapy remains one of the main methods for patients with advanced LUAD. Due to the resistance, the effect of this chemotherapy was not satisfactory. Therefore, studying the mechanism of cisplatin (DDP) resistance is essential for promoting the effect of this therapeutic strategy. Therefore, this work sought to probe the impact of E2F Transcription Factor 7 (E2F7) on LUAD resistance and the molecular regulatory mechanism. The mRNA expression level of the target gene E2F7 in LUAD was predicted by bioinformatics analysis, and regulatory miRNA upstream of the target gene was identified. The mRNA and protein expression of E2F7 in LUAD cells was detected through quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot, respectively. The expression of miR-195-5p in LUAD cells was measured via qRT-PCR. E2F7 high and low expression groups underwent enrichment analysis by utilizing Gene Set Enrichment Analysis software. The targeting relationship of miR-195-5p and E2F7 was validated by conducting a dual-luciferase reporter assay. The cell viability was tested through cell counting kit-8. The cell cycle was examined by flow cytometry. DNA damage level was determined via Comet assay and Western blot assay. The findings indicated that the mRNA and protein levels of E2F7 were high in LUAD. MiR-195-5p was the regulatory miRNA upstream of E2F7, and lowly expressed in LUAD. The cell experiments suggested that E2F7 advanced the DDP resistance of LUAD cells by repressing DNA damage. Finally, the rescue assay manifested that miR-195-5p overexpression could abate inhibition of E2F7 overexpression on the DNA damage and the DDP sensitivity of LUAD cells. MiR-195-5p raised the DDP sensitivity of LUAD cells by advancing the DNA damage in LUAD cells via inhibition of E2F7.
肺腺癌 (LUAD) 是全球最致命的恶性肿瘤之一。铂类联合化疗仍然是晚期 LUAD 患者的主要治疗方法之一。由于耐药性的存在，这种化疗的效果并不理想。因此，研究顺铂 (DDP) 耐药的机制对于促进这种治疗策略的效果至关重要。因此，这项工作旨在探讨 E2F 转录因子 7 (E2F7) 对 LUAD 耐药性的影响及其分子调控机制。通过生物信息学分析预测 LUAD 中靶基因 E2F7 的 mRNA 表达水平，并鉴定靶基因上游的调节 miRNA。通过定量逆转录聚合酶链反应 (qRT-PCR) 和 Western blot 分别检测 LUAD 细胞中 E2F7 的 mRNA 和蛋白表达。通过 qRT-PCR 测量 LUAD 细胞中 miR-195-5p 的表达。利用基因集富集分析软件对 E2F7 高表达和低表达组进行富集分析。通过双荧光素酶报告基因实验验证 miR-195-5p 和 E2F7 的靶向关系。通过细胞计数试剂盒-8 检测细胞活力。通过流式细胞术检测细胞周期。通过彗星试验和 Western blot 检测 DNA 损伤水平。结果表明，E2F7 在 LUAD 中的 mRNA 和蛋白水平较高。miR-195-5p 是 E2F7 的上游调节 miRNA，在 LUAD 中低表达。细胞实验表明，E2F7 通过抑制 DNA 损伤促进 LUAD 细胞对 DDP 的耐药性。最后，挽救实验表明，miR-195-5p 的过表达可以减轻 E2F7 过表达对 LUAD 细胞的 DNA 损伤和 DDP 敏感性的抑制作用。miR-195-5p 通过抑制 E2F7 来提高 LUAD 细胞的 DDP 敏感性，从而促进 LUAD 细胞的 DNA 损伤。
