PRMT1-meFOXO1通路在低温常压等离子体诱导的三阴型乳腺癌细胞铁死亡中的作用机制研究

Triple negative breast cancer is a kind of breast cancer with high degree of malignancy and difficult to be treated. Cold atmospheric plasma (CAP) is the fourth state high-energy substance composed of electrons, ions and molecules, which can effectively kill some cancer cells. Our previous study found that CAP can promote the death of triple negative breast cancer cells, however, the relevant molecular mechanism is unknown. Our preliminary results focusing on CAP treatment in SUM 149 cells showed that CAP made cells smaller, the RPL8 expression was increased, Ferrostatin-1 significantly reduced cell death, which inferred that CAP might induce ferroptosis; the PRMT1 and the FOXO1 methylation expression were increased, the protein and phosphorylation level of FOXO1 were decreased, Ferrostatin-1 reduced the expression of PRMT1 and increased the expression of FOXO1, which inferred that PRMT1-FOXO1 might involve in the regulation of CAP induced ferroptosis in SUM 149 cells. According on above preliminary results, we speculate that the PRMT1-meFOXO1 pathway promotes the ferroptosis of triple-negative breast cancer cells induced by CAP. We plan to apply Electron Microscopy, ferroptotic inhibition experiments, transcriptome sequencing data analysis, and molecular biology techniques to explore the main style and its regulatory mechanism of triple negative breast cancer cell death induced by CAP. The discovery of CAP induced ferroptosis will provide new ideas for the clinical treatment of triple negative breast cancer, and the study on the mechanism of ferroptosis will provide precise molecular targets and theoretical basis for the development of drugs similar to the function of CAP.

低温常压等离子体（CAP）是由电子，离子，分子等构成的第四态物质，可有效杀死多种癌细胞。我们前期发现：CAP可以促进三阴型乳腺癌细胞（简称“细胞”）的死亡，但死亡类型及机制不详。本研究预实验发现：CAP使细胞形态缩小，RPL8表达增加，Ferrostatin-1使细胞存活率增加，提示细胞发生铁死亡；CAP使PRMT1的mRNA及其蛋白、FOXO1甲基化水平增加，使FOXO1蛋白及其磷酸化水平下降，Ferrostatin-1使PRMT1水平降低，FOXO1水平升高，提示PRMT1-FOXO1可能调控细胞铁死亡。因此我们推测PRMT1通过促进FOXO1的甲基化和去磷酸化调控CAP诱导的细胞铁死亡。本项目拟通过电镜，转录组数据分析及分子生物学技术等探索CAP诱导细胞死亡的类型及调控机制。细胞铁死亡的发现将为三阴型乳腺癌的临床治疗提供新的思路，其机制研究将为开发类似于CAP功能的药物提供靶点。

三阴性乳腺癌（TNBC）是一类恶性程度高，异质性高，易复发的乳腺癌，由于缺乏有效的靶点，目前尚无有效的靶向治疗方案。低温常压等离子体（CAP）是区别于气、液、固的第四态物质，临床上可用于伤口消毒，促进伤口愈合。有研究表明等离子体可有效杀伤癌细胞，然而机制不明确。该研究的目的是明确CAP对TNBC细胞的铁死亡易感性，及探索其可能的调控机制。本研究发现CAP可选择性的诱导TNBC细胞铁死，EGFR在CAP诱导的TNBC细胞中其磷酸化被激活，抑制EGFR的磷酸化可减少CAP诱导的TNBC细胞铁死亡，铁死亡抑制剂可减少CAP诱导下TNBC细胞中磷酸化EGFR的激活，FOXO1的磷酸化或甲基化可能促进CAP诱导TNBC细胞铁死亡，铁死亡抑制剂可增加TNBC细胞中FOXO1的表达，FOXO1作为EGFR的下游分子参与调控CAP诱导的TNBC细胞铁死亡。本项目率先发现 CAP 主要诱导TNBC细胞发生铁死亡，通过 CAP 处理TNBC细胞前后的反转录数据富集分析筛选出候选靶基因及蛋白，为研究 CAP 诱导的TNBC细胞铁死亡机制的突破口，层层递进揭秘EGFR-FOXO1 调控 CAP 诱导的TNBC细胞铁死亡的分子调控机制。CAP 治疗TNBC分子机制的研究将为 CAP 应用于肿瘤领域奠定坚实的理论基础，同时也为进一步开发出 CAP 类似功能及与 CAP 联合治疗的药物提供精确可靠的分子靶点。