肝癌细胞内质网应激诱导的NAT10表达对RNA乙酰化ac4C修饰靶基因的筛选与鉴定及其对药物敏感性的影响

内质网应激（ERS）介导肝癌耐药机制尚不明确。NAT10介导RNA乙酰化ac4C修饰是目前研究热点，但与ERS相关的耐药关系未见报道。我们前期发现肝癌细胞ERS后NAT10染色质开放性、转录组及蛋白表达均明显增加，抑制NAT10可增加药物敏感性，提示ERS相关耐药与NAT10介导的RNA乙酰化ac4C修饰有关。本项目将首先明确肝癌细胞ERS诱导NAT10表达的上游调控机制，然后在细胞水平上，利用acRIP-seq分析转录组ac4C修饰位点，联合LongRNA-seq和Ribo-seq系统发现NAT10作用靶点和调控网络，预测并验证与耐药相关的靶基因及信号通路。通过调控相关靶基因观察药物敏感性变化，阐明相关信号通路。在此基础上，通过荷瘤小鼠模型研究NAT10介导的RNA乙酰化ac4C修饰对肝癌药物敏感性的影响。本研究将进一步阐明肝癌ERS相关耐药分子机制，有望发现肝癌药物治疗作用新靶点。

It is well believed that endoplasmic reticulum stress plays an important role in drug resistance in hepatocellular carcinoma (HCC).However, the molecular and cellular mechanisms underlying drug resistance induced by endoplasmic reticulum stress are largely unknown.Currently,N4-acetylcytidine (ac4C) as an mRNA modification that is catalyzed by the acetyltransferase NAT10 is becoming a hot topic in cancer area. However, the molecular and cellular mechanisms underlying the relationship between RNA ac4C and drug resistance induced by endoplasmic reticulum stress are still needed further investigation.Our previous studies found that NAT10 in hepatoma cells significantly changed after ERS stimulation using ATAC-seq , transcriptome sequencing platform and Western-blot.Inhibition of NAT10 can increase drug sensitiveness.Base on these finding, we propose the hypothesis that drug resistance mediated by ERS is closely related to RNA ac4C catalyzed by the acetyltransferase NAT10. To test this hypothesis, we first clarify the upstream mechanism of NAT10 expression induced by ERS in hepatocellular carcinoma cells.We will use acRIP-seq platform to perform ac4C Mapping in Poly(A) RNA.Then we used methods such as LongRNA-seq and Ribo-seq to predicted the functional of target RNA ac4C catalyzed by the acetyltransferase NAT10 induced by endoplasmic reticulum stress in drug resistance.The functions of target RNA ac4C catalyzed by the acetyltransferase NAT10 and related signal pathways will be confirmed.Lastly, gene editing of hepatoma cells on tumor-bearing mouse models will be performed to test the effects of RNA ac4C catalyzed by the acetyltransferase NAT10 induced by endoplasmic reticulum stress and drug sensitiveness.The proposed studies above not only could further precisely demonstrate the molecular mechanisms of drug resistance induced by endoplasmic reticulum stress but also provide solid evidence and basis for developing novel drug target in the future.