PILOT 2 IMPACT OF HYALURONAN TURNOVER ON SIGNALING THROUGH ENDOSOMA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在侵袭性前列腺癌中，肿瘤细胞部分通过产生和转化透明质酸(HA)来操纵细胞外基质，透明质酸是一种糖胺多聚糖聚合物。尽管HA在正常成人前列腺中可以忽略不计，但它会在前列腺癌及其骨转移瘤中积聚。定量检测肿瘤细胞相关的HA及其周转酶--透明质酸酶--可预测侵袭性临床进展。由透明质酸合成酶(HAS)合成的细胞表面HA聚合物和由Hyal1合成的HA低聚物以相反的方式调节信号通路，至少部分通过影响特定细胞表面受体的活性来控制细胞的增殖和运动。具体地说，HAS生物合成酶的过表达降低了质膜上黏附和生长因子受体的水平，并损害了细胞黏附和运动。Hyal1的同时存在缓解了这些影响，但其机制尚不清楚。这项建议将继续新的观察，即升高的透明蛋白，既是一种分泌酶，也是一种溶酶体酶，增加了稳定选择用于其表达的前列腺肿瘤细胞的内吞循环速度。工作假说是，Hyal1通过调节囊泡运输的速度影响多个信号通路，从而通过维持重要受体的表面呈现以及回收和释放作为信号的生物有效的HA消化产物来促进肿瘤细胞的生长和运动。目的1将量化操作HAS和Hyal1引起的HA摄取改变的参数，并确定其对运动性和侵袭性的影响。目的2将确定HA和透明质酸1被内吞的途径(S)，以及它们被摄取后的命运。目标3将直接表征受体周转率对HAS或Hyal1改变的反应。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In aggressive prostate cancer, tumor cells manipulate the extracellular matrix in part by production and turnover of hyaluronan (HA), a glycosaminoglycan polymer. Although negligible in normal adult prostate, HA accumulates in prostate tumors and their resultant bone metastases. Quantification of tumor cell-associated HA and its turnover enzyme, the hyaluronidase Hyal1, predicts invasive clinical progression. Cell surface HA polymers, synthesized by HA synthase enzymes (HAS), and HA oligomers generated from the polymers by Hyal1, modulate signaling pathways that control proliferation and motility in an opposing fashion, at least partially by impacting activity of specific cell surface receptors. Specifically, overexpression of the HAS biosynthetic enzyme reduces plasma membrane levels of adhesion and growth factor receptors, and impairs both cell adhesion and motility. These effects are relieved by the concurrent presence of Hyal1, but the mechanism is not understood. This proposal will pursue the novel observation that elevated Hyal1, which is both a secreted and a lysosomal enzyme, increases the rate of endocytic recycling in the prostate tumor cells stably selected for its expression. The working hypothesis is that Hyal1 impacts multiple signaling pathways by modulating the rate of vesicular trafficking, thus contributing to tumor cell growth and motility by maintaining surface presentation of important receptors and by recycling and releasing biologically potent digestion products of HA that serve as signals. Aim 1 will quantify parameters of altered HA uptake resulting from manipulation of HAS and Hyal1, and determine the consequences for motility and invasion. Aim 2 will identify the route(s) by which HA and Hyal1 are endocytosed, and their fate after uptake. Aim 3 will directly characterize receptor turnover rates in response to HAS or Hyal1 alteration.