DAP5-dependent translational control and breast cancer metastasis

肿瘤的发生发展、肿瘤的形成、进展、侵袭和转移都与选择性mRNA有关 但对致癌基因翻译的许多理解仍有待确定。 我们最近发现了一种新的帽子依赖的信使核糖核酸翻译机制，它建立了一个新的范式 对于转化性监管，因为它依赖于上限，但不涉及规范的启动前机制。 我们发现，大约20%的使用eIF4E/eIF4GI因子的mRNAs不需要标准的eIF4E/eIF4GI因子 翻译起始复合体DAP5/eIF3d，它利用翻译的帽结合活性 启动因子eIF3d而不是eIF4E和eIF4GI同源物，DAP5。我们发现DAP5/eIF3d对于 乳腺癌转移的动物模型与人类乳腺癌转移密切相关。这里 我们建议研究DAP5/eIF3d介导的mRNA翻译在乳腺癌发生和发展中的作用。 转移。我们将确定DAP5/eIF3d介导的mRNA翻译在肿瘤发生中的作用。 用同基因小鼠乳腺癌模型侵袭和转移人异种移植乳房 肿瘤细胞系模型和异种患者来源的异种移植模型，后两种模型进行 在免疫受损的小鼠身上。我们将描述DAP5/eIF3d与eIF4GI/eIF4E启动的要求 翻译对癌细胞上皮向间充质转化、间质组织侵袭、血管形成的影响 内渗、外渗、迁移，防止细胞脱离和迁移引起的细胞凋亡， 和殖民主义。其他研究将通过全基因组转译和翻译组学分析来表征 与mRNAs相比，由DAP5/eIF3d选择性翻译的、进展为转移所需的mRNAs 在动物模型中由eIF4E/eIF4GI翻译。这些研究将进一步加深我们对DAP5- 选择性信使核糖核酸翻译驱动转移性肿瘤进展中的特定致癌途径。我们 还将测试特定的DAP5 mRNA翻译靶点在DAP5介导的转移瘤中的重要性 进步。最后，将对DAP5/eIF3d介导的机制(S)进行研究 选择性的信使核糖核酸翻译。研究将集中在一种特定形式的mRNA甲基化修饰的作用上 之所以被称为M6A，是因为我们已经找到了支持其重要性的强有力的初步数据。

Cancer development, tumor formation, progression, invasion and metastasis all involve selective mRNA translation but much of the understanding by which oncogenic translation occurs remains to be characterized. We recently discovered a new mechanism of cap-dependent mRNA translation that established a new paradigm for translational regulation, in that it is cap-dependent but does not involve the canonical pre-initiation machinery. We showed that the canonical eIF4E/eIF4GIfactors are not required for approximately 20% of mRNAs that use the translation initiation complex known as DAP5/eIF3d, which utilizes the cap binding activity of translation initiation factor eIF3d rather than eIF4E and eIF4GI homolog, DAP5. We found that DAP5/eIF3d is essential for breast cancer metastasis in animal models and strongly associated with human breast cancer metastasis. Here we propose to study the role of DAP5/eIF3d-mediated mRNA translation in breast cancer development and metastasis. We will determine the roles of DAP5/eIF3d-mediated mRNA translation in tumor development, invasion and metastasis, using syngeneic mouse mammary cancer models, human xenotransplant breast cancer cell line models and a heterogeneous patient derived xenograft model, the latter two models carried out in immune impaired mice. We will characterize the requirement for DAP5/eIF3d versus eIF4GI/eIF4E initiation of translation on cancer cell epithelial to mesenchymal transition (EMT), stromal tissue invasion, vascular intravasation, extravasation, migration, prevention of apoptosis resulting from cell detachment and migration, and colonization. Other studies will characterize by genome-wide trancriptomic and translatomic analyses the mRNAs selectively translated by DAP5/eIF3d and required for progression to metastasis, compared to mRNAs translated by eIF4E/eIF4GI in animal models. These studies will further our understanding of the role of DAP5- selective mRNA translation in driving specific oncogenic pathways involved in metastatic tumor progression. We will also test the importance of specific DAP5 mRNA translation targets in DAP5-mediated metastatic tumor progression. Finally, studies will be carried out to understand the mechanism(s) for DAP5/eIF3d-mediated selective mRNA translation. Studies will focus on the role of a specific form of mRNA modification by methylation known as m6A because we have found strong preliminary data in support of its importance.