铁死亡是一种受调节的细胞死亡，其特征是铁积累和脂质过氧化。非小细胞肺癌 (NSCLC) 中铁死亡调节的分子机制尚不清楚。在这项研究中，我们发现蛋白激酶 A (PKA) 抑制增强了 NSCLC 细胞的铁死亡易感性，细胞活力降低和脂质过氧化增加就证明了这一点。我们进一步鉴定了 cAMP 反应元件蛋白 1 (CREB1)（一种转录因子和 PKA 的底物）作为铁死亡的关键调节因子。 CREB1的敲低使NSCLC细胞对铁死亡诱导剂（FINs）敏感，并消除了PKA抑制剂和激动剂的作用，揭示了CREB1在铁死亡调节中的关键作用。使用高通量筛选方法以及随后通过染色质免疫沉淀 (ChIP) 和双荧光素酶测定进行的验证，我们发现 CREB1 转录激活硬脂酰辅酶 A 去饱和酶 (SCD)，这是一种催化饱和脂肪酸转化为单不饱和脂肪酸的酶。 SCD 通过降低多不饱和脂肪酸用于脂质过氧化的可用性而赋予铁死亡抗性，并且其过度表达在体外挽救了 CREB1 敲低对铁死亡的影响。此外，在存在有效 FIN 咪唑酮 Erastin (IKE) 的情况下，CREB1 敲低可抑制异种移植肿瘤的生长，而这种效应可被 SCD 逆转。最后，我们从公共数据集和我们的机构中​​发现，CREB1 的高表达与 NSCLC 患者的不良预后相关。总的来说，本研究阐明了 PKA/CREB1/SCD 轴在调节 NSCLC 铁死亡中的作用，针对该通路可能为治疗 NSCLC 患者提供新策略。© 2023。作者。

Ferroptosis is a type of regulated cell death characterized by iron accumulation and lipid peroxidation. The molecular mechanisms underlying ferroptosis regulation in non-small cell lung cancer (NSCLC) are poorly understood. In this study, we found that protein kinase A (PKA) inhibition enhanced ferroptosis susceptibility in NSCLC cells, as evidenced by reduced cell viability and increased lipid peroxidation. We further identified cAMP-responsive element protein 1 (CREB1), a transcription factor and a substrate of PKA, as a key regulator of ferroptosis. Knockdown of CREB1 sensitized NSCLC cells to ferroptosis inducers (FINs) and abolished the effects of PKA inhibitor and agonist, revealing the pivotal role of CREB1 in ferroptosis regulation. Using a high-throughput screening approach and subsequent validation by chromatin immunoprecipitation (ChIP) and dual-luciferase assays, we discovered that CREB1 transcriptionally activated stearoyl-CoA desaturase (SCD), an enzyme that catalyzes the conversion of saturated fatty acids to monounsaturated fatty acids. SCD conferred ferroptosis resistance by decreasing the availability of polyunsaturated fatty acids for lipid peroxidation, and its overexpression rescued the effect of CREB1 knockdown on ferroptosis in vitro. Besides, CREB1 knockdown suppressed xenograft tumor growth in the presence of Imidazole Ketone Erastin (IKE), a potent FIN, and this effect was reversed by SCD. Finally, we showed that high expression of CREB1 was associated with poor prognosis in NSCLC patients from public datasets and our institution. Collectively, this study illustrates the effect of PKA/CREB1/SCD axis in regulating ferroptosis of NSCLC, targeting this pathway may provide new strategies for treating NSCLC patients.© 2023. The Author(s).