DEREGULATION BY HU PROTEINS IN LUNG CANCER

HU蛋白是一个RNA结合蛋白家族，包含三种RNA- 具有约束力的主题。HUD、Huc和Hel-N1在神经元组织中表达， 而HUR则无处不在地被表达。神经元HU蛋白也是 在所有小细胞肺癌(SCLC)和大约一半的小细胞肺癌中表达 神经母细胞瘤。它们可以与不稳定的不稳定序列结合 原癌基因mRNAs，如myc基因家族的那些。MYC 基因在小细胞肺癌和神经母细胞瘤中经常被激活 通过增加Myc蛋白水平的事件。建议的自然资源 HU蛋白在RNA降解和神经元特异性中的作用 剪接将允许这些蛋白质干扰适当的mrna衰退。 以及癌细胞的剪接。 该项目的具体目标是检验以下假设： 1)HU蛋白在小细胞肺癌中的表达在转录后调控中起作用 通过改变降解和/或剪接模式来解除基因调控 MRNAs编码影响细胞生长或黏附的蛋白质 属性。2)提高细胞内HU蛋白的水平 这些蛋白质的内源性水平不高或很低都会导致 与观察到的某些异常相似的基因调控 在SCLC中。为了验证我们的两个假设，我们建议使用 以下是具体目标：1)确定……的级别和身份 HU蛋白在小细胞肺癌和肺癌细胞系中的表达 非SCLC类型。1b)测量的表达水平和半衰期 原癌基因myc家族在缺乏和缺失的细胞中的mRNAs 表达HU蛋白以确定是否存在相关性 在一个或多个HU蛋白的表达和不适当的myc之间存在 M RNA降解。1c)以确定特定的HU蛋白是否显示出 对特定myc mRNA靶标的结合偏好，如c-，N-， 或L-myc基因体外非翻译区，并确定胡 在体内，蛋白质与myc mRNA相互作用。1d)分析表达式 和编码细胞外基质蛋白的mRNAs的剪接模式 小细胞肺癌和非小细胞肺癌细胞系中的生长刺激蛋白， 为了确定细胞中是否观察到剪接变化 表达一种或多种HU蛋白。2a)在细胞中表达Hu蛋白 通常缺少它们，以及2b)以确定HU的后果 在这些单元格中表达，如上文1b和1d所述。2C)使用 在2a建立的细胞系，以获得受 HU蛋白的表达。HU蛋白在小细胞肺癌中作用的研究 为开始了解RNA的作用提供了一个独特的机会- 癌症发生发展过程中的结合蛋白。

Hu proteins are a family of RNA-binding proteins containing three RNA- binding motifs. HuD, HuC and Hel-N1 are expressed in neuronal tissue, while HuR is expressed ubiquitously. The neuronal Hu proteins are also expressed in all small cell lung cancers (SCLCs) and about half of all neuroblastomas. They can bind to the destabilizing sequences of labile proto-oncogene mRNAs, such as those of the family of myc genes. myc genes are frequently oncogenically activated in SCLC and neuroblastoma by events that increase the levels of Myc protein. The proposed natural function of Hu proteins in RNA degradation and neuronal-specific splicing would allow these proteins to interfere with proper mRNA decay and splicing in cancer cells. The specific aims of this project are to test the following hypotheses: 1) Hu protein expression in SCLC plays a role in post-transcriptional gene deregulation by altering the degradation and/or splicing pattern of mRNAs encoding proteins that affect the cell's growth or adhesion properties. 2) Increasing the levels of Hu proteins inside a cell with no or low endogenous levels of these proteins will lead to changes in gene regulation that are similar to some of the abnormalities observed in SCLC. To test our two hypotheses, we propose studies with the following specific aims: 1a) To determine the levels and identities of Hu proteins expressed in lung cancer cell lines, both of the SCLC and non-SCLC type. 1b) To measure the level of expression and half-life of mRNAs of the myc family of proto-oncogenes genes in cells lacking and expressing Hu proteins in order to determine whether a correlation exists between expression of one or more Hu proteins and improper myc mRNA degradation. 1c) To determine whether specific Hu proteins show a binding preference for particular myc mRNA targets, such as the c-, N-, or L-myc untranslated regions in vitro, and to determine whether Hu proteins interact with myc mRNA in vivo. 1d) To analyze the expression and splicing pattern of mRNAs encoding extracellular matrix proteins and growth stimulatory proteins in cell lines of the SCLC and non-SCLC type, in order to determine whether splicing changes are observed in cells expressing one or more Hu proteins. 2a) to express Hu proteins in cells that normally lack them, and 2b) to determine the consequences of Hu expression in these cells as outlined under 1b and 1d above. 2c) To use the cell lines established in 2a to obtain genes that are affected by Hu protein expression. The study of the role of Hu proteins in SCLC offers a unique opportunity to begin to understand the role of RNA- binding proteins in the development and progression of cancer.