Chromosome 1q ceRNAs in Melanoma Progression and Metastasis

项目总结 转移是恶性黑色素瘤相关死亡的主要原因。过去十年的研究表明 揭示了转移过程主要不是由基因变化驱动的。相反，放松对基因的管制 通过表观遗传、转录或转录后机制以及拷贝数来表达 改变可能会促进黑色素瘤的转移。我们之前的工作描述了信使RNA是如何参与 蛋白质编码无关的转录后调控，通过隔离来自其他生物的microRNAs(MiRNAs) 转录本，我们称之为这种天然的miRNA海绵竞争内源RNA(CeRNAs)。 去调控的Cerna表达与癌症的发展有因果关系，因此与基因组复制有关。 CENA基因的数目增加可能是黑色素瘤恶性进展的重要驱动因素。我们有 发现了位于染色体1q上的一组黑色素瘤Cerna基因，它经历了拷贝数 25%-50%的黑色素瘤患者增加(1qGAIN)。1qGAIN在转移瘤中更常见，提示1qGAIN ceRNAs 可能导致黑色素瘤的进展。我们的预测确定CEP170是一个有效的1qGAIN Cerna，并且 初步实验揭示了其在体外和体内的致癌作用。另外两个1qGAIN CERNA， NUCKS1和ZC3H11A显示出致癌潜能，并增强了CEP170介导的作用。因此， 1Q的增加可能导致促进黑色素瘤转移的多个CERNAs的过度表达 隔离的肿瘤抑制miRNAs。我们已经确定了五个与转移相关的miRNAs，它们是 被CEP170隔离，促进黑色素瘤细胞迁移和侵袭。在这项提案中，我们将 系统研究1qGAIN ceRNAs在黑色素瘤转移中的致癌作用。具体而言，在目标1中 我们将研究CEP170的3‘非编码区是否促进黑色素瘤在miRNA结合位点特异性中的扩散 采用转移模型和自体模型。在目标2中，我们将评估来自 内源性CEP170转录本反对转移，如果这些miRNAs具有肿瘤抑制活性 在黑色素瘤细胞中。此外，我们将确定和表征介导CEP170的下游效应器- 激起的表型。最后，在目标3中，我们将研究NUCKS1和ZC3H11A是否促进CEP170的效果 通过增加miRNA的封存。我们还将测试剩余的1qGAIN ceRNA中是否有任何一个，总共10个， 具有致癌活性，并与CEP170协同作用。我们预计我们的研究将揭示 1qGAIN CERNAs与黑色素瘤转移的相关性及进一步阐明CENA-CERNA的作用机制 介导的黑色素瘤进展和转移。

PROJECT SUMMARY Metastasis is the main cause of deaths related to malignant melanoma. Studies over the last decade have revealed that the metastatic process is not primarily driven by genetic changes. Instead, deregulation of gene expression through epigenetic, transcriptional, or posttranscriptional mechanisms as well as copy number alterations may promote melanoma metastasis. Our previous work described how messenger RNAs engage in protein coding-independent posttranscriptional regulation by sequestering microRNAs (miRNAs) from other transcripts, and we termed such natural miRNA sponges competitive endogenous RNAs (ceRNAs). Deregulated ceRNA expression has been causally linked to cancer development, and thus genomic copy number gains of ceRNA genes may be an important driver of malignant progression of melanoma. We have identified a cluster of melanoma ceRNA genes localized on chromosome 1q, which undergoes copy number gains (1qGAIN) in 25-50% of melanoma. 1qGAIN is more frequent in metastases, suggesting that 1qGAIN ceRNAs may contribute to melanoma progression. Our predictions identified CEP170 as a potent 1qGAIN ceRNA, and preliminary experiments revealed its oncogenic role in vitro and in vivo. Two additional 1qGAIN ceRNAs, NUCKS1 and ZC3H11A, exhibited oncogenic potential and enhanced the CEP170-mediated effects. Thus, gains of 1q may lead to overexpression of multiple ceRNAs that promote melanoma metastasis by sequestering tumor suppressive miRNAs. We have identified five metastasis-associated miRNAs that are sequestered by CEP170 and that promote melanoma cell migration and invasion. In this proposal, we will systematically examine the oncogenic role of 1qGAIN ceRNAs in melanoma metastasis. Specifically, in Aim 1 we will examine if the 3'UTR of CEP170 promotes melanoma dissemination in a miRNA binding site-specific manner using metastasis and autochthonous models. In Aim 2 we will assess if the release of miRNAs from the endogenous CEP170 transcript opposes metastasis, and if these miRNAs have tumor suppressive activity in melanoma cells. Moreover, we will identify and characterize downstream effectors that mediate the CEP170- provoked phenotype. Finally, in Aim 3 we will examine if NUCKS1 and ZC3H11A boost the effect of CEP170 by augmenting miRNA sequestration. We will also test if any of the remaining 1qGAIN ceRNAs, ten in total, possess oncogenic activity and cooperate with CEP170. We expect that our study will reveal the biological relevance of 1qGAIN ceRNAs to melanoma metastasis and further elucidate the mechanisms underlying ceRNA- mediated melanoma progression and metastasis.