PIAS1- hnRNPA2/B1依赖的外泌体miRNAs分拣机制在胰腺癌耐药性中的作用研究

pancreatic cancer lacks effective biomarkers for predicting gemcitabine chomesensitivity. In our previous work, mi-RNAs expression profiling difference was compared between parental and gemcitabine-resistant pancreatic cancer cell lines, between before and after gemcitabine treatment in pancreatic cancer patients and confirmed by cell function verification. miR-1290, miR-221, miR-134 and miR-1246 are found to be potential mi-RNA molecules that mediate gemcitabine resistance, and the enrichment of miR-1290, miR-1246 and miR-134 in exosomes is dependent on SUMO-modified hnRNPA2/B1 protein. Further studies confirmed that PIAS1 (SUMO-modified E3 ligase), which is highly expressed in gemcitabine resistant cells, can increase the stability of hnRNPA2/B1, and its high expression is closely related to gemcitabine resistance. Therefore, this study intends to retrospectively analyze the possibility of miR-1290, miR-1246,miR-134 and hnRNPA2/B1 as non-invasive clinical markers for predicting gemcitabine resistance in patients undergoing chemotherapy from a large sample based on the findings of previous studies. Meanwhile, PIAS1-hnRNPA2/B1-dependent exosomes sorting mechanism will been further explored in animal and cell models.

胰腺癌缺乏预判化疗敏感性判断的生物学指标。本课题组在前期工作中通过对比普通及吉西他滨耐药性胰腺癌细胞株外泌体中的miRNA表达谱初筛，胰腺癌患者血液样本复检，细胞功能验证等多轮筛选后，发现miR-1290，miR-221，miR-134及miR-1246是潜在的介导吉西他滨耐药性的miRNA分子，其中miR-1290,miR-1246,miR-134在外泌体中的富集依赖于SUMO修饰的hnRNPA2/B1蛋白。进一步试验证实，耐药株中高表达的PIAS1(SUMO修饰E3连接酶)能够增加hnRNPA2/B1的稳定性，且其高表达与吉西他滨耐药性密切相关。因此，本项目拟在前期基础上，从大样本回顾性分析评估miR-1290,miR-1246, miR-134及其分拣蛋白作为预测吉西他滨耐药性临床指标的可能性。同时，在动物及细胞模型中深入研究PIAS1- hnRNPA2/B1依赖的外泌体分拣机制。

本研究利用生物信息技术并结合基础实验，筛选出了多个胰腺癌的治疗靶点和预后相关标志物。通过对吉西他滨耐药的胰腺癌细胞进行高通量测序，结合数据库比对后筛选出了胰腺癌的治疗靶点，揭示了一个可能介导 PC 的耐药性，包含 lncRNA（MIR210HG、SNHG1 和 LOC729970）和 mRNA（RAB3D、DDX17 和 SPNS2）的枢纽；并通过TCGA、GTEx、GEO数据库的大量应用，筛选出了多个胰腺癌的治疗靶点和预后相关标志物，包括PLS3、COL17A1、EVL、CA12、SCAMP1、SCAMP5等，并对这些靶分子的分子机制进行了一定的研究。