PDF(Pubmed)
Abstract：
High mobility group box 1 (HMGB1) is secreted from activated immune cells, necrotic cells, and certain cancers. Previous studies have reported that different patterns of post-translational modification, particularly acetylation and oxidation, mediate HMGB1 release and confer distinct extracellular HMGB1 signaling activity. Here we report that cisplatin but not carboplatin induces secretion of HMGB1 from human A549 non-small cell lung cancer (NSCLC) cells. Cisplatin-mediated HMGB1 secretion was dose-dependent and was regulated by nuclear exportin 1 (XPO1) also known as chromosomal maintenance 1 (CRM1) rather than adenosine diphosphate (ADP)-ribosylation, acetylation, or oxidation. HMGB1, as well as lysine acetylation and cysteine disulfide oxidation of secreted HMGB1, were monitored by sensitive and specific assays using immunoprecipitation, stable isotope dilution, differential alkylation, and nano liquid chromatography parallel reaction monitoring/high-resolution mass spectrometry (nano-LC-PRM/HRMS). A major fraction of the HMGB1 secreted by low-dose cisplatin treatment of A549 NSCLC cells was found to be in the fully reduced form. In contrast, mainly oxidized forms of HMGB1 were secreted by dimethyl sulfoxide (DMSO)-mediated apoptosis. These findings suggest that inhibition of XPO1 could potentiate the anti-tumor activity of cisplatin by increasing the nuclear accumulation of HMGB1 protein, an inhibitor of cisplatin DNA-adduct repair. Furthermore, low-dose cisplatin therapy could modulate the immune response in NSCLC through the established chemokine activity of extracellular reduced HMGB1. This could potentially enhance the efficacy of subsequent immunotherapy treatment.
摘要：
高迁移率族蛋白1（HMGB1）由活化的免疫细胞分泌，坏死细胞,某些癌症。以前的研究报道，翻译后修饰的不同模式，特别是乙酰化和氧化，介导HMGB1释放并赋予不同的细胞外HMGB1信号传导活性。在这里，我们报道了顺铂而不是卡铂诱导人A549非小细胞肺癌（NSCLC）细胞分泌HMGB1。顺铂介导的HMGB1分泌是剂量依赖性的，并且受到核输出蛋白1（XPO1）的调节，也称为染色体维持1（CRM1），而不是二磷酸腺苷（ADP）-核糖基化。乙酰化,或氧化。HMGB1，以及分泌的HMGB1的赖氨酸乙酰化和半胱氨酸二硫化物氧化，通过使用免疫沉淀的敏感和特异性测定法进行监测，稳定同位素稀释，微分烷基化，和纳米液相色谱平行反应监测/高分辨质谱(nano-LC-PRM/HRMS)。发现低剂量顺铂治疗A549NSCLC细胞分泌的HMGB1的主要部分为完全还原形式。相比之下,二甲基亚砜（DMSO）介导的细胞凋亡分泌主要氧化形式的HMGB1。这些发现表明，抑制XPO1可以通过增加HMGB1蛋白的核积累来增强顺铂的抗肿瘤活性。顺铂DNA加合物修复的抑制剂。此外，低剂量顺铂治疗可以通过建立细胞外减少的HMGB1的趋化因子活性来调节NSCLC的免疫应答。这可能潜在地增强后续免疫疗法治疗的功效。
