暴露在颗粒物上与DNA损伤和肺癌风险相关联。p53蛋白在DNA损伤早期通过多个位点的磷酸化被激活，并影响细胞结局。我们的研究旨在评估标准空气污染物：碳黑（CB）、城市尘土（UD）和纳米碳黑（NPCB）（浓度分别为100µg/mL-1/24小时）对增殖和处于静止状态的A549细胞及对顺铂（CisPT）暴露后存活的细胞的细胞周期、DNA损伤和在Ser 9、Ser 20、Ser 46和Ser 392位点的53磷酸化的影响。通过流式细胞术使用特定荧光染料标记的单克隆抗体和双变量荧光分布散点图分析，对细胞亚群中的磷酸化p53进行定量。顺铂、UD和NPCB增加了位点特异性p53磷酸化，产生独特的模式。NPCB无论在细胞周期上如何均激活所有位点，而UD更具选择性。p53 Ser 9-P和p53 Ser 20-P与G0/G1期经过顺铂处理的细胞数量呈正相关，NPCB和NPCB + CisPT产生了类似的效应。在经过NPCB和CisPT处理的静止A549细胞中，p53 Ser 20-P和Ser 392-P之间也发现了正相关和整体反应，但在UD处理中未发现。p53磷酸化在Ser 20和Ser 392位点的表达与细胞周期阻滞之间的相互依赖关系表明，翻译后修饰变化与功能激活有关。我们的数据表明，响应特定DNA损伤的p53蛋白磷酸化是由多条相互独立和综合的途径驱动的，以产生在癌症预防和治疗中至关重要的功能激活。版权所有 © 2023 Niechoda, Milewska, Roslan, Ejsmont and Holownia.

Exposure to particulate matter is associated with DNA damage and the risk of lung cancer. Protein p53 is activated by multi-site phosphorylation in the early stages of DNA damage and affects cell outcome. Our study aimed to assess the effect of (100 µg/mL-1/24 h) standardized air pollutants: carbon black (CB), urban dust (UD), and nanoparticle carbon black (NPCB) on cell cycle, DNA damage and 53 phosphorylation at Ser 9, Ser 20, Ser 46, and Ser 392 in proliferating and quiescent A549 cells and in cells that survived cisplatin (CisPT) exposure. Phosphorylated p53 was quantified in cell subpopulations by flow cytometry using specific fluorochrome-tagged monoclonal antibodies and analysis of bivariate fluorescence distribution scatterplots. CisPT, UD and NPCB increased site-specific p53 phosphorylation producing unique patterns. NPCB activated all sites irrespectively on the cell cycle, while the UD was more selective. p53 Ser 9-P and p53 Ser 20-P positively correlated with the numbers of CisPT-treated cells at G0/G1, and NPCB and NPCB + CisPT produced a similar effect. A positive correlation and integrated response were also found between Ser 20-P and Ser 392-P in resting A549 cells treated with NPCB and CisPT but not UD. Interdependence between the expression of p53 phosphorylated at Ser 20, and Ser 392 and cell cycle arrest show that posttranslational alterations are related to functional activation. Our data suggest that p53 protein phosphorylation in response to specific DNA damage is driven by multiple independent and integrated pathways to produce functional activation critical in cancer prevention and treatment.Copyright © 2023 Niechoda, Milewska, Roslan, Ejsmont and Holownia.