METASTATIC REGULATION OF DIFFERENTIAL SPLICING OF CD44

这是香农奖，为这项研究提供部分支持 项目低于指定研究所的资助范围，但 都在最优秀的边缘。香农奖旨在提供 支持测试该方法的可行性；开发进一步的测试 并改进研究方法；进行二次分析或可用 数据集；或执行可演示PI的离散项目 研究能力或为已经功成名就的 申请。下面的摘要摘自原始文件 由首席调查员提交。 描述(改编自调查员摘要)：期间 转移，肿瘤细胞脱离原发肿瘤块并通过 通过细胞外基质侵入身体的其他部位。这个 肿瘤细胞穿透基质并相互黏附的能力 部分原因是肿瘤细胞上存在细胞表面蛋白 与细胞外基质或细胞表面相互作用 其他细胞上的蛋白质。一种这样的细胞表面蛋白，其 细胞外结构域与转移潜能相关 多功能黏附糖蛋白CD44，表达于 哺乳动物体内各种各样的细胞。来自CD44基因的RNA经历了 广泛的可选剪接。该基因含有10个内部盒式磁带 可替代地包括产生CD44变异形式的外显子 带有额外的影响结合的胞外结构域 携带CD44的细胞的特异性。包含特定的子集 可选外显子与转移扩散有很强的相关性 在结肠癌、乳腺癌、卵巢癌和脑癌中表达 CD44的不同形式现在被用来评估肿瘤的转移潜能 人类癌症。 含交替包涵外显子的CD44基因的表达 与转移相关足以使同源基因发生转移 肿瘤细胞和CD44变异型抗体防止转移 在动物模型中传播。因此，拼接模式的改变 CD44mRNA的表达足以使肿瘤细胞发生转移。这 建议旨在了解涉及到的分子机制 CD44在卵巢和乳腺转移中的选择性剪接 肿瘤细胞系及其转移选择的比较 与刺激白细胞生长时发生的剪接或 在发育早期的上皮细胞和组织形成期间。 具体目标包括：1)确定顺式作用序列 监管CD44替代外显子的包含。这些项目的目标是 实验是为了区分组织剪接的调节- 剪接调控中的特定因素 通用剪接机械的水平或活动。2)测定 规管纳入 CD44外显子在转移细胞和正常细胞中的变化 选择性剪接事件之间关系的研究 CD44转移变异体的产生与正常组织的建立 在哺乳动物早期发育过程中。

THIS IS A SHANNON AWARD PROVIDING PARTIAL SUPPORT FOR THE RESEARCH PROJECTS THAT FALL SHORT OF THE ASSIGNED INSTITUTE'S FUNDING RANGE BUT ARE IN THE MARGIN OF EXCELLENCE. THE SHANNON AWARD IS INTENDED TO PROVIDE SUPPORT TO TEST THE FEASIBILITY OF THE APPROACH; DEVELOP FURTHER TESTS AND REFINE RESEARCH TECHNIQUES; PERFORM SECONDARY ANALYSIS OR AVAILABLE DATA SETS; OR CONDUCT DISCRETE PROJECTS THAT CAN DEMONSTRATE THE PI'S RESEARCH CAPABILITIES OR LEND ADDITIONAL WEIGHT TO AN ALREADY MERITORIOUS APPLICATION. THE ABSTRACT BELOW IS TAKEN FROM THE ORIGINAL DOCUMENT SUBMITTED BY THE PRINCIPAL INVESTIGATOR. DESCRIPTION (adapted from the investigator's abstract): During metastasis, tumor cells break away from the primary tumor mass and pass through the extracellular matrix to invade other areas of the body. The ability of tumor cells to penetrate the matrix and attach to each other is, in part, due to the presence of cell surface proteins on tumor cells that interact with either the extracellular matrix or with cell surface proteins on other cells. One such cell surface protein whose extracellular domains have been correlated with metastatic potential is the multifunctional adhesion glycoprotein, CD44, which is expressed in a wide variety of cells in mammals. RNA from the CD44 gene undergoes extensive alternative splicing. The gene contains 10 internal cassette exons that are alternatively included to produce variant forms of CD44 with additional extracellular domains that influence the binding specificity of cells bearing CD44. Inclusion of a specific sub-set of the alternative exons has a strong correlation with metastatic spread in colon, breast, ovarian and brain cancer such that expression of variant forms of CD44 is now used to assess metastatic potential of human cancers. Expression of CD44 cDNAs containing the alternatively-included exons associated with metastasis is sufficient to confer metastasis on syngenic tumor cells and antibodies to the variant form of CD44 prevent metastatic spread in animal models. Therefore, alteration in the splicing pattern of CD44 mRNA is sufficient to render a tumor cell metastatic. This proposal is aimed at understanding the molecular mechanism involved in the alternative splicing of CD44 during metastasis of ovarian and breast cancer tumor cell lines and comparing the metastatic alternative splicing to that occurring during growth stimulation of leukocyte or epithelial cells and during tissue formation in early development. Specific aims include: 1) determination of the cis-acting sequences that regulate inclusion of the CD44 alternative exons. The goal of these experiments is to distinguish regulation of splicing due to tissue- specific factors from regulation of splicing due to alterations in the levels or activities of the general splicing machinery; 2) determination of the trans-acting factors required for regulation of inclusion of the CD44 alternative exons in metastatic versus normal cells; 3) Investigation of the relationship between the alternative splicing event producing the CD44 metastatic variants and normal tissue establishment during early mammalian development.