AR-v12基因突变导致胃癌侵袭转移的分子机制研究

Gastric cancer metastasis often leads to poor prognosis and death. Identifying mechanisms that related to gastric cancer metastasis can help to improve prognosis and reduce mortality. The researches found that androgen receptor (AR) plays an important role in a variety of tumor metastasis processes, but the function and molecular mechanism of AR in gastric cancer remains to be studied. Our previous study found that the high expression of splice variant AR-v12 in gastric cancer could promote gastric cancer cells migration and invasion with independing on hormone ligand. Patients with AR-v12 gene mutation in gastric cancer were more likely to metastasis and poor prognosis. Bioinformatics prediction suggested that AR-v12 gene mutation may bind to the upstream transcription factor YY-1 and participate in the regulation of downstream metastasis-associated genes. Based on this, we hypothesized that AR-v12 gene mutation targeting YY-1 can enhance transcriptional activity and regulate metastasis-associated gene expression leading to gastric cancer metastasis. This study aims to determine that the role of AR-v12 gene mutation in gastric cancer metastasis from cells, tissues, molecules and animals multiple levels; to elucidate the mechanism that AR-v12 gene mutation regulated by YY-1 and downstream metastasis-associated genes. This study explores the molecular mechanism of gastric cancer metastasis from a new perspective of AR-v12 gene mutation, and provides a new target therapy for gastric cancer .

胃癌转移常导致患者预后不良甚至死亡。明确胃癌转移相关机制有助于改善预后降低死亡率。研究报道雄激素受体（AR）在多种肿瘤转移过程中起重要作用，但在胃癌中的功能及分子机制有待研究。申请人前期研究发现胃癌中不依赖配体激素刺激的剪切体AR-v12高表达促进胃癌细胞迁移、侵袭，胃癌组织中AR-v12基因突变患者更易发生转移且预后不良，生物信息学预测AR-v12突变基因可能与上游转录因子YY-1靶向结合并参与调控下游转移相关基因。据此我们提出假说：AR-v12基因突变靶向结合YY-1增强转录活性调控转移相关基因表达导致胃癌发生转移。本课题拟从细胞、组织、分子及动物等多层次确定AR-v12基因突变在胃癌转移中的作用；阐明AR-v12基因突变受YY-1调节的机制；明确AR-v12基因突变与转移相关的下游靶基因。本研究从AR-v12基因突变的新视角探讨胃癌转移的分子机制，为进展期胃癌靶向治疗提供新的靶标。

胃癌是我国常见的恶性肿瘤之一，胃癌侵袭转移是导致预后差的主要原因之一。基因突变在胃癌恶性进展中发挥重要作用。因此，寻找胃癌转移的驱动基因尤为重要。研究表明雄激素受体（AR）是一类类固醇受体，在肿瘤发生发展过程中发挥至关重要的作用。在本研究中，我们采用外显子测序技术筛选出影响胃癌细胞侵袭转移的功能基因AR，我们发现AR基因在胃癌患者中高频突变，且突变患者预后生存明显短于未发生突变的胃癌患者，提示AR突变与胃癌患者不良预后相关。TCGA数据库分析显示AR与甲基化、TMB、突变数、临床分期等均有相关性，同时分析TIMER数据库分析AR表达与免疫细胞浸润显著相关。CCK-8、流式细胞术、细胞划痕和Transwell实验提示AR突变型比野生型更加促进胃癌细胞增殖、侵袭和迁移。通过RNA-seq和高效液相色谱法进行机制研究筛选出可能与AR突变发挥生物学功能有关的下游特异基因。综上所述，我们认为AR突变可能作为胃癌的新预后标记及潜在治疗靶点。