LncRNA-LOC00132891/PCDH20通路调控葡萄膜黑色素瘤侵袭转移的机制研究

Uveal melanoma (UM) is the most common primary malignant intraocular tumor in adults and has a strong potential to metastasize. Previous studies have shown that mutation of proto-oncogenes and chromosomal aberrations occur early in UM tumorigenesis. Recent studies have also highlighted the epigenetic mechanisms in UM progression. Our previous work has identified a novel lncRNA-LOC00132891, which was upregulated in UM tissues and cells. LOC00132891 silencing in UM cell lines significantly suppressed tumor growth and metastasis in vitro and in vivo. Genome-wide cDNA array revealed that PCDH20 was remarkably activated upon LOC00132891 knockdown. Therefore, we speculate that LOC00132891 may regulate PCDH20 expression by epigenetic factors. We propose Chromatin Immunoprecipitation and RNA Guided Chromosome Conformation Capture method to further explore LOC00132891 guided epigenetic modification at PCDH20 promoter. In this study, we will elaborate how LOC00132891/PCDH20 pathway regulates the progression of uveal melanoma, and aim to provide a potential therapeutic target in the diagnosis and treatment of UM.

葡萄膜黑色素瘤（UM）是成人中发病率最高的眼内恶性肿瘤，易发肝转移，致死率高。早期研究认为基因突变或染色体异常是UM发生的诱因，近来UM发病的表观遗传机制亦受到关注。前期研究发现，长非编码RNA（lncRNA）LOC00132891在UM组织和细胞系中异常高表达，在UM细胞中沉默LOC00132891能显著抑制细胞的生长转移能力，进一步研究显示，LOC00132891敲除明显激活PCDH20基因的表达。我们推测：LOC00132891通过关键因子调控下游靶基因PCDH20的表达，进而促进UM侵袭转移。因此，本项目提出以lncRNA调控为突破口，利用染色质免疫共沉淀、RNA 介导的染色体构象捕捉等方法探究LOC00132891对PCDH20的表观遗传修饰作用，阐明LOC00132891/PCDH20通路调控UM生长转移的相关机制，为UM的临床诊断和治疗提供理论依据和新靶点。

葡萄膜黑色素瘤（Uveal Melanoma, UM）是成人最常见的原发性眼内恶性肿瘤，转移性高，死亡率高居不下。UM极易通过血行转移至全身重要器官，即使原发灶得以控制，仍有25%和34%的患者发生远处脏器转移。研究认为，UM的发生和GNAQ/GNA11突变以及BAP1缺失都可能导致肿瘤发生。此外，UM的发生除受细胞遗传学改变影响，还和甲基化水平、基因印记改变和染色体构象变化等表观遗传学改变密切相关。基于以上阐述，本项目通过染色质免疫共沉淀、 染色体寡核苷酸沉淀、RNA免疫共沉淀等分子生物学与表观遗传学的技术手段，深入分析LOC00132891介导PCDH20基因表观遗传修饰在UM转移能力变化中的关键作用，阐明PCDH20基因在UM转移中的重要功能,并进一步通过动物实验揭示UM中LOC00132891调控PCDH20的表达机理，为治疗恶性肿瘤提供新思路，同时对lncRNA引发的机制研究提供有益的借鉴。