THZ1通过CDK7抑制RNAPII磷酸化调控超级增强子及关联的致癌基因导致胃癌细胞凋亡的分子机制研究

胃癌出现多种基因突变型，导致靶向药物作用效果不佳，限制了临床精准治疗。已知周期蛋白依赖性激酶7（CDK7)具有周期和转录调控双重作用，超级增强子（SE）在转录过程中富集大量的转录因子和辅因子发挥调控基因表达的功能。文献报道小分子抑制剂THZ1具有抗肿瘤作用，但在胃癌治疗中的作用及机制并不明确。本课题预实验发现：1，THZ1抑制胃癌细胞活性且下调CDK7和RNAPII蛋白表达及磷酸化；2，mRNA测序分析发现THZ1导致细胞周期、转录调控和凋亡等基因下调。结合研究背景，我们提出假说：THZ1通过CDK7抑制RNAPII磷酸化，进而抑制转录过程中SEs及相关致癌基因表达，导致肿瘤细胞死亡。因此，我们拟采用细胞模型（CCK8、FACs、基因敲除、WB等）、肿瘤动物模型（免疫组化、小动物活体成像等）、生物信息学（RNA-Seq、CHIP-Seq）等方法。为临床胃癌精准治疗和新药研发提供理论基础。

There are a variety of gene mutations in gastric cancer, leading to poor effects of targeted drugs and limiting clinical precision treatment. It has known that cyclin-dependent kinase 7 (CDK7) exhibits a dual role of cycle and transcription regulation, as well as the super enhancer (SE) enriches a large number of transcription factors and cofactors during the transcription process to regulate gene expression. It is reported in the literature that the small molecule inhibitor THZ1 has anti-tumor effects, but its role and mechanism in the treatment of gastric cancer are not clear. Preliminary experiments of this subject found that: 1. THZ1 inhibits the activity of gastric cancer cells and down-regulates the expression and phosphorylation of CDK7 and RNAPII; 2. mRNA sequencing analysis found that THZ1 leads to the down-regulation of genes such as cell cycle, transcription regulation and apoptosis. Based on previous studies and these pilot experimental results, we put forward our hypothesis: THZ1 inhibits RNAPII phosphorylation through CDK7, thereby inhibiting the expression of SEs and related oncogenes during transcription, leading to tumor cell death. To verify this, we are planning to perform cell models (CCK8, FACs, gene knockout, WB, etc.), tumor animal models (immunohistochemistry, small animal live imaging, etc.), bioinformatics (RNA-Seq, CHIP-Seq) and other methods. This study will provide a strong theoretical basis for the precise treatment of clinical gastric cancer and the development of new drugs.