肿瘤转移是恶性黑素瘤患者死亡的首要因素。我们前期发现Linc00681在转移性恶性黑素瘤中高表达，并竞争性结合miR-16，上调YAP1表达，促进恶性黑素瘤细胞侵袭转移；敲低Linc00681后，YAP1表达降低，但YAP1磷酸化水平及PTPN14表达增高，既往文献报道PTPN14促进YAP1磷酸化。进一步实验证实Linc00681与RNF2蛋白结合，且沉默RNF2亦上调PTPN14表达。故我们提出假说：Linc00681不仅在胞浆中竞争性吸附miR-16上调YAP1表达；还在胞核中通过结合RNF2蛋白抑制PTPN14转录，阻遏YAP1磷酸化，增强YAP1核转位，促进恶性黑素瘤转移。本研究拟通过RIP、ChIP、原位杂交、动物实验等从细胞-组织-整体层面阐明Linc00681通过调控YAP1表达及磷酸化促进黑素瘤转移的具体机制。本课题将有助于明确恶性黑素瘤转移的分子机制及发现新的治疗靶点。

Metastasis is the primary factor account for the death of malignant melanoma(MM). Our preliminary studies found linc00681 was upregulated in the tissues of metastasis melanoma，and could competitively bind with miR-16, upregulate YAP1 expression, and promote migration and invasion in MM cells. While, YAP1 was down-regulated, and the phosphorylated levels of YAP1 and PTPN14 expression which was proved to be a key regulator of YAP1 phosphorylation were upregulated after silencing Linc00681 expression in MM cells. Further investigation revealed that Linc00681 could interact with RNF2 protein, and silencing RNF2 also upregulated PTPN14 expression. Thus, we hypothesis that Linc00681 promotes invasion-metastasis cascade of MM not only by sponging miR-16 to enhance YAP1 expression in cytoplasma, but also interacting with RNF2 in nucleus to repress PTPN14 expression and YAP1 phosphorylation, and promote YAP1 nuclear transposition. Thus, we will clarify the mechanism of Linc00681 in regulation of YAP1 expression and YAP1 phosphorylation during MM metastasis from cell-tissue-whole organism levels by performing RIP, ChIP, in situ hybridization histochemistry, and animal experiments. Our study will contribute to explicit the molecular mechanisms of metastasis of MM, and identify new therapeutic targets of MM.