PILOT 2 IMPACT OF HYALURONAN TURNOVER ON SIGNALING THROUGH ENDOSOMA

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 在侵袭性前列腺癌中，肿瘤细胞部分地通过透明质酸（HA）（一种糖胺聚糖聚合物）的产生和周转来操纵细胞外基质。 尽管在正常成人前列腺中可以忽略不计，但HA在前列腺肿瘤及其导致的骨转移中蓄积。 肿瘤细胞相关HA及其转换酶Hyal 1的定量可预测侵袭性临床进展。由HA合成酶（HAS）合成的细胞表面HA聚合物和由Hyal 1从聚合物产生的HA寡聚体至少部分地通过影响特定细胞表面受体的活性来调节以相反方式控制增殖和运动性的信号传导途径。 具体而言，HAS生物合成酶的过表达降低了粘附和生长因子受体的质膜水平，并损害细胞粘附和运动性。 Hyal 1的同时存在缓解了这些影响，但其机制尚不清楚。 该提案将追求新的观察结果，即升高Hyal 1，这是一种分泌和溶酶体酶，增加了前列腺肿瘤细胞中稳定选择其表达的内吞再循环的速率。 工作假设是Hyal 1通过调节囊泡运输的速率来影响多种信号传导途径，从而通过维持重要受体的表面呈递以及通过回收和释放作为信号的HA的生物学上有效的消化产物来促进肿瘤细胞生长和运动。 目的1将量化由HAS和Hyal 1操纵引起的改变的HA摄取的参数，并确定运动和侵袭的后果。 目的2将确定HA和Hyal 1被内吞的途径，以及它们在摄取后的命运。 目标3将直接表征响应于HAS或Hyal 1改变的受体周转率。

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.