Identification of oncogenic drivers in aggressive B cell Lymphoma by ribosome profiling and a novel primary human lymphocyte transformation assay

弥漫性大B细胞淋巴瘤（DLBCL）是最常见的非霍奇金淋巴瘤。它是一种具有侵袭性和毁灭性的癌症。尽管联合化疗有可能治愈，但超过三分之一的患者将死于疾病。重要的是，DLBCL的发病率随着年龄的增长而增加，许多老年患者根本无法耐受所需的化疗。DLBCL的某些亚型已被确定对所有现有疗法的反应都特别差。因此，迫切需要开发更有效和耐受性更好的“靶向”治疗方法。在过去的十年里，我们对这种疾病的潜在生物学的理解有了相当大的进步。这些发现大多来自于研究不同亚型淋巴瘤基因群的活性差异。这些“基因表达”研究主要是检测每个细胞中mRNA的总量。mRNA是一种信使分子，在被翻译成最终的活性产物（称为蛋白质）之前，它携带来自基因DNA的指令。一般来说，更活跃的基因产生更多的mRNA，这就是为什么mRNA通常被用作基因活性的代理。然而，最近已经清楚的是，并不是所有的mRNA分子都以同样的效率“翻译”成蛋白质。此外，在癌症中经常发现，某些携带对癌症有利指令的mRNA分子可能会被肿瘤优先翻译。最近的技术使我们有机会测量每个mRNA的翻译速率。我将使用这种技术来识别那些被不同亚型DLBCL优先翻译的mrna。那些翻译率变化最大的基因/ mrna将在细胞培养系统中进行测试，以确定那些对淋巴瘤的发展和生长贡献最大的基因/ mrna。最终，抑制这些基因的药物可能被证明对淋巴瘤的治疗有用。我预计这种方法将为开发抗淋巴瘤药物治疗确定新的靶点。此外，我将研究一些mRNA被淋巴瘤细胞优先翻译的机制。我将使用计算方法筛选优先翻译的mRNA，以确定淋巴瘤细胞可能用来控制翻译的共同序列。然后，我将使用这些序列作为诱饵来确定导致淋巴瘤中翻译改变的“翻译因子”。我将研究这些翻译因子的活性是如何被淋巴瘤特异性信号通路或突变控制的。事实上，已经在淋巴瘤细胞中已知的调节翻译的因子中发现了突变，但这些突变的功能意义尚待研究。总的来说，这个项目将提供一个详细的了解淋巴瘤细胞如何破坏其基因的正常严格调节的活动。在这样做的过程中，这个项目可能会为淋巴瘤的新形式的靶向治疗提供机会。此外，我们对淋巴瘤中翻译调控机制的了解可能被证明与其他疾病，特别是其他类型的癌症具有更广泛的相关性。

Diffuse Large B Cell Lymphoma (DLBCL) is the most common form of non-Hodgkin Lymphoma. It is an aggressive and devastating form of cancer. Although potentially curable with combination chemotherapy, more than a third of patients will succumb to their disease. Importantly, the incidence of DLBCL increases with age and many older patients are simply unable to tolerate the required chemotherapy. Certain subtypes of DLBCL have been identified that respond particularly poorly to all existing therapies. Thus there is a pressing need for the development of more effective and better tolerated, "targeted" treatments. Over the last decade there have been considerable advances in our understanding of underlying biology of this disease. Much of this has arisen from studies that examine how the activity of cohorts of genes differs between different subtypes of lymphoma. These "gene expression " studies have predominantly examined the total amount mRNA in each cell. mRNA is a messenger molecule that carries instructions from the gene's DNA before being translated in to the final active product, termed the protein. In general more active genes make more mRNA, which is why mRNA has generally been used as a proxy for gene activity. However, recently it has become clear that not all mRNA molecules are "translated" into protein with equal efficiency. Furthermore, a frequent finding in cancer is that certain mRNA molecules that carry instructions advantageous to the cancer may be preferentially translated by the tumor. Recent technology now allows the opportunity to measure the translational rate for each individual mRNA. I will use this technique to identify those mRNAs that are preferentially translated by the different subtypes of DLBCL. Those genes / mRNAs with the greatest changes in translational rate will be tested in cell culture systems to identify those that contribute most to the development and growth of the lymphoma. Ultimately drugs designed to inhibit these genes may prove useful in the treatment of lymphoma. I anticipate that this approach will identify new targets for the development of anti-lymphoma drug treatments. In addition I will investigate the mechanism by which some mRNA is preferentially translated by lymphoma cells. I will use a computational approach to screen preferentially translated mRNA to identify common sequences that the lymphoma cells may use to control the translation. I will then use these sequences as bait to identify the "translation factors' responsible for the altered translation in lymphoma. I will investigate how the activity of these translation factors is controlled, either by lymphoma specific signaling pathways or by mutation. Indeed, mutations have already been identified in factors known to regulate translation in lymphoma cells but the functional significance of these mutations is yet to be investigated.Overall this project will provide a detailed understanding of how lymphoma cells corrupt the normally tightly regulated activity of their genes. In doing so this project may reveal opportunities for new forms of targeted treatment in lymphoma. In addition much of what we learn about the mechanisms of corrupted translational regulation in lymphoma may prove to be of broader relevance to other diseases, in particular other types of cancer.