Abstract：
Metastasis is one of the most significant causes for deterioration of breast cancer, contributing to the clinical failure of anti-tumour drugs. Excessive inflammatory responses intensively promote the occurrence and development of tumour, while protease-activated receptor 2 (PAR2) as a cell membrane receptor actively participates in both tumour cell functions and inflammatory responses. However, rare investigations linked PAR2-mediated inflammatory environment to tumour progression. Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology is an emerging and powerful gene editing technique and can be applied for probing the new role of PAR2 in breast cancer metastasis, but it still needs the development of an efficient and safe delivery system. This work constructed anionic bovine serum albumin (BSA) nanoparticles to encapsulate CRISPR/Cas9 plasmid encoding PAR2 sgRNA and Cas9 (tBSA/Cas9-PAR2) for triggering PAR2 deficiency. tBSA/Cas9-PAR2 remarkably promoted CRISPR/Cas9 to enter and transfect both inflammatory and cancer cells, initiating precise PAR2 gene editing in vitro and in vivo. PAR2 deficiency by tBSA/Cas9-PAR2 effectively suppressed NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome signalling in inflammatory microenvironment to magnify stimulator of interferon genes (STING) signalling, reactive oxygen species (ROS) accumulation and epithelial-mesenchymal transition (EMT) reversal, consequently preventing breast cancer metastasis. Therefore, this study not only demonstrated the involvement and underlying mechanism of PAR2 in tumour progression via modulating inflammatory microenvironment, but also suggested PAR2 deficiency by tBSA/Cas9-PAR2 as an attractive therapeutic strategy candidate for breast cancer metastasis.
摘要：
转移是乳腺癌恶化的最重要原因之一，导致抗肿瘤药物的临床失败。过度的炎症反应强烈促进肿瘤的发生和发展,而蛋白酶激活受体2（PAR2）作为细胞膜受体积极参与肿瘤细胞功能和炎症反应。然而,罕见的研究将PAR2介导的炎症环境与肿瘤进展联系起来。聚集的规则间隔短回文重复序列(CRISPR)/Cas9技术是一种新兴的强大的基因编辑技术，可应用于探测PAR2在乳腺癌转移中的新作用。但是它仍然需要开发一个高效和安全的输送系统。这项工作构建了阴离子牛血清白蛋白（BSA）纳米颗粒来封装编码PAR2sgRNA和Cas9（tBSA/Cas9-PAR2）的CRISPR/Cas9质粒，以引发PAR2缺乏症。tBSA/Cas9-PAR2显著促进CRISPR/Cas9进入和转染炎症细胞和癌细胞，在体外和体内启动精确的PAR2基因编辑。tBSA/Cas9-PAR2缺乏可有效抑制炎症微环境中NOD样受体热蛋白结构域相关蛋白3（NLRP3）炎症体信号传导，以放大干扰素基因刺激因子（STING）信号传导，活性氧（ROS）积累和上皮间质转化（EMT）逆转，从而预防乳腺癌转移。因此,这项研究不仅证明了PAR2通过调节炎症微环境参与肿瘤进展及其潜在机制，但也提示tBSA/Cas9-PAR2缺乏作为乳腺癌转移的有吸引力的候选治疗策略.
