Lnc-DSGC结合APAF1调节胃癌顺铂耐药的作用机制研究

Platinum compounds represented by cisplatin (DDP) are still widely used in the treatment of many malignant tumors, but the cisplatin resistance and clinical toxic side effects severely limit its clinical application. The mechanism of cisplatin resistance is still not clear, and further study is needed. Long non-coding RNA (lncRNA) plays an important role in the development of various diseases including gastric cancer, but there are few reports on the mechanism of lncRNA regulating cisplatin resistance in gastric cancer. This study is based on the pre-constructed gastric cancer organoid. According to their sensitivity to cisplatin, these organoids are divided into DDP-Sensitivity and DDP-Tolerance groups. Through lncRNA array and RNA pulldown methods, we found Lnc-DSGC was significantly up-regulated in the DDP-Tolerance group, and it could bind to the apoptotic enzyme activator APAF1, which regulates the sensitivity of gastric cancer cells to cisplatin. Based on these, we will use cellular, organoid, animal models and cohort study with molecular biological skills and epidemiological method to clarify the mechanism of Lnc-DSGC-APAF1 in cisplatin resistance in gastric cancer, and we will also explore the reasons for the increased expression of Lnc-DSGC in cisplatin-resistant gastric cancer cells. These efforts may provide a theoretical basis for the monitoring and effective intervention of cisplatin resistance in gastric cancer.

顺铂广泛应用于许多恶性肿瘤治疗，但肿瘤对顺铂耐药及顺铂毒副作用严重限制了其临床应用。顺铂的作用机制需要进一步研究。长链非编码RNA（lncRNA）在多种疾病包括胃癌发生发展中发挥重要作用，但lncRNA调节胃癌顺铂耐药的研究报道甚少。本课题基于胃癌类器官（organoid），根据对顺铂的敏感性，胃癌organoid分为DDP-Sensitivity和DDP-Tolerance组，通过lncRNA芯片结合RNA免疫沉淀技术发现lncRNA-Lnc-DSGC在DDP-Tolerance组显著上调，并通过结合凋亡酶激活因子APAF1调节胃癌细胞顺铂敏感性。本项目拟通过细胞，类器官和动物模型，结合人群样本，利用分子生物学技术和流行病学方法探讨Lnc-DSGC结合APAF1调节胃癌顺铂耐药的作用机制，并研究Lnc-DSGC在胃癌顺铂耐药细胞中表达上升的原因，为胃癌顺铂耐药的监测和干预提供理论依据。

顺铂广泛应用于包括胃癌在内的多个恶性肿瘤治疗，但顺铂耐药及毒副作用严重限制了其临床应用。本项目通过细胞，类器官和动物模型，结合人群样本，利用分子生物学技术和流行病学等方法发现一种与凋亡蛋白酶激活因子1(APAF1)结合的lncRNA(ABL)，即Lnc-DSGC。研究发现ABL在胃癌（GC）组织中显著升高，可作为GC患者的独立预后因素。此外，ABL可以抑制GC细胞凋亡并促进GC细胞存活和多药耐药。机制上，ABL直接与RNA结合蛋白IGF2BP1结合识别METTL3介导的ABL上的m6A修饰，维持ABL稳定。同时，ABL与APAF1的WD1/WD2结构域结合，竞争性地阻止细胞色素C（Cyt c）与APAF1相互作用，阻断凋亡小体组装和Caspase-9/3激活，最终导致GC细胞对多个化疗药物耐药。同时，我们也发现使用纳米材料共组装ABL siRNA和紫杉醇（PTX）可以促进PTX的抗肿瘤作用。在课题执行期内，我们还揭示RNA甲基化转移酶METTL3通过调控HDGF/GLUT4/ENO2轴增加糖酵解和血管生成来促进胃癌的发生和转移，提示METTL3可能是胃癌潜在的预测和治疗靶点。总的来说，本研究结果表明ABL及METTL3等多个分子可作为GC潜在的预后生物标志物和治疗靶点，依托于本课题，以第一作者（含共一）或通讯作者（含共通）发表和此研究内容相关SCI论文9篇，标记此课题号文章8篇，还有2篇文章在审稿中。项目实施期间获得中国博士后科学基金特别资助（站中）及南京市杰出青年基金项目。