微型RNA (MicroRNAs or miRNAs) 表現不正常已被證明影響許多疾病的產生。此外，研 究指出比起傳統mRNA，微型RNA是為更有效率的分類癌症依據。已有利用微型RNA模 擬物或抑制物，來干擾失調的訊息傳導路徑，在臨床測試中來達到治療疾病的目的。 Ｍitogen-activated protein kinase (MAPK/ERK) signaling 的活化與許多細胞癌化息息相 關，例如黑色素癌。之前上個計畫我們利用microRNA晶片及MAPK活化抑制劑的實驗去 篩選可能參與MAPK路徑的微型RNA。經分析後，篩選出與MAPK路徑有顯著關係的二 十二個微型RNA。研究miR-524-5p在MAPK/ERK signaling的角色已發表並且另一微型 RNA:miR-596在抑制黑色素癌及其在影響的機制以及利用在黑色素癌病人檢體中 miR-524-5p的表現可以判別良性痣及黑色素癌(ROC=0.8645) 的研究成果正投稿中。由最 近在MAPK/ERK signaling 領域的頂尖科學家所撰寫的綜合評論，也引用我們的研究成 果，可證明我們研究的重要性 (Masliah-Planchon, 2016)。我們會藉由這項優勢來繼續系 統性的探討與篩選出MAPK路徑有顯著關係的微型RNA。 在這個研究計畫，我們希望延續研究MAPK路徑有顯著關係的微型RNA，主要目標更進 一步在了解在黑色素癌及對標靶藥PLX4032抗藥性的黑色素癌的效果，以及在人類癌症 血液及組織中，是否可為一個偵測及預後的生物標記。深入探討MAPK路徑相關的二十 二個微型RNA，其中有些微型RNA也會負調控MAPK路徑及其機制做詳細的探索。其中 會著重在探討微型RNA對腫瘤細胞的生長、細胞增生、細胞轉移、和細胞凋零的影響。 此研究計畫的新發現，將可以闡明新一層調控MAPK/ERK signaling的機制。此外，此研 究新知識，有潛力可應用於發展新的診斷方法或對疾病的治療，並可以增進基礎和轉譯 醫學的研究。 ;The mitogen-activated protein kinase (MAPK/ERK) signaling occupies an essential role in many cancer progressions, including melanoma. BRAF is mutated frequently in melanoma (~60-80%) and this causes MAPK/ERK signaling activation. BRAF inhibitors such as PLX4032 (Vemurafenib), are active in BRAF mutant melanoma patients, but the majority of patients will develop drug resistance within an average 7 months via reactivation of MAPK/ERK pathway through different ways. The drug resistance is always the concern for small molecule inhibitors so that there has been a drive to design novel therapies to circumvent this problem. Several experimental evidences showed that microRNA (miRNAs) can modulate the effectiveness of cell signaling pathways, and utilizing miRNAs to mimic or inhibit endogenous miRNA expression may provide a powerful therapeutic strategy to interfere with key signal transduction pathways. We have successfully identified 22 miRNAs associated with MAPK/ERK pathway, and our studies demonstrated that miR-524-5p regulates MAPK/ERK signaling and suppresses melanoma. The results regarding to miR-524-5p have been published. In addition, we recently investigated the status of miR-524-5p expression in Taiwan and Western melanoma specimen. Receiver operating characteristic curve (ROC curve) of miR-524-5p showed an accurate discrimination between diagnostic melanoma and nevus groups (ROC= 0.8645). Moreover, regarding another candidate miRNA-miR596, we discovered this miRNA can suppress melanoma proliferation through MEK1, and two anti-apoptosis proteins, MCL1 and BCL2L1 directly. These two manuscripts have been submitted and under journal reviewing. The significance of our work has been specifically recognized and mentioned in a review article by a leading scientist in the field (Masliah-Planchon, 2016). Given that the advantage of being the leading position in this subject, we will further systematically study these 22 miRNAs related with MAPK/ERK pathway from our screen. In this project, we will delineate whether these candidate MAPK/ERK miRNAs (22 miRNAs) could be the detection and/or prognosis biomarkers, and have the therapeutic effects for melanoma. We will focus on whether some miRNAs can inhibit survival and migration ability in melanoma and PLX4032 resistant melanoma in vitro and in vivo and dissect the gene targets and the mechanisms of the candidate miRNAs. The ultimate goal of this proposed research is to get the clear picture of molecular network of candidate MAPK/ERK miRNAs in signaling pathways and functions of these miRNAs. Finally, the knowledge we gained from this study can potentially be extended in discovery of new diagnosis or therapy targets for diseases, and can be used in both basic and translational medicine research.
