Department of Epidemiology and Biostatistics, Key Laboratory for Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, China.
Department of Epidemiology and Biostatistics, Key Laboratory for Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, China.
Eur J Cancer. 2021 Jul;151:94-105. doi: 10.1016/j.ejca.2021.04.008. Epub 2021 May 8.
This study aimed to identify the functional genes and genetic variants associated with the prognosis of pancreatic ductal adenocarcinoma (PDAC) and reveal the mechanism underlying their prognostic roles.
First, we implement a two-stage exome-wide association study in a total of 1070 patients to identify the genetic variant correlated with PDAC prognosis. Then we performed fine mapping through bioinformatics analysis and dual-luciferase reporter assays to reveal the causal functional variant and prognostic gene. Next, we established the gene knockdown, knockout, and overexpression cell lines with small interfering RNA, CRISPR/Cas9, and lentivirus, respectively, and investigated the gene function on cell proliferation and migration in vivo and in vitro. Finally, we performed the RNA-seq to elucidate downstream genes and mechanisms altering PDAC prognosis.
We identified the CAV1-CAV2 locus tagged by rs8940 was significantly associated with PDAC prognosis, and rs10249656 in the 3'untranslated region of CAV2 was the real functional variant, which upregulated CAV2 expression through abolishing miR-548s binding. We observed upregulated CAV2 in PDAC and the higher expression correlated with worse prognosis. Transient knockdown of CAV2 inhibited PDAC migration without affecting proliferation rate. Knockout of CAV2 suppressed PDAC progression and metastasis, whereas stable overexpression of CAV2 promoted. Overexpressed CAV2 promoted the PDAC progression and metastasis via perturbing genes in the focal adhesion (CCND1, IGTA1, and ZYX) and extracellular matrix organisation (PLOD2, CAST, and ITGA1) pathways mechanically.
These findings shed light on an important role of CAV2 on PDAC progression and the prognostic impact of its genetic variation.
本研究旨在鉴定与胰腺导管腺癌（PDAC）预后相关的功能基因和遗传变异，并揭示其预后作用的机制。
首先，我们在总共 1070 例患者中进行了两阶段外显子全基因组关联研究，以鉴定与 PDAC 预后相关的遗传变异。然后，我们通过生物信息学分析和双荧光素酶报告基因检测进行精细定位，以揭示因果功能变异和预后基因。接下来，我们分别使用小干扰 RNA、CRISPR/Cas9 和慢病毒建立基因敲低、敲除和过表达细胞系，并在体内和体外研究基因对细胞增殖和迁移的功能。最后，我们进行了 RNA-seq 以阐明改变 PDAC 预后的下游基因和机制。
我们鉴定出 CAV1-CAV2 基因座被 rs8940 标记与 PDAC 预后显著相关，rs10249656 是 CAV2 3'非翻译区的真实功能变异，通过消除 miR-548s 的结合而上调 CAV2 的表达。我们观察到 PDAC 中 CAV2 的表达上调，并且表达水平较高与预后较差相关。CAV2 的瞬时敲低抑制了 PDAC 的迁移而不影响增殖率。CAV2 的敲除抑制了 PDAC 的进展和转移，而稳定过表达 CAV2 则促进了其进展和转移。过表达的 CAV2 通过干扰细胞黏附（CCND1、IGTA1 和 ZYX）和细胞外基质组织（PLOD2、CAST 和 ITGA1）途径中的基因，促进了 PDAC 的进展和转移。
这些发现揭示了 CAV2 在 PDAC 进展中的重要作用及其遗传变异的预后影响。
