Regulation of Tumor and Metastatic Growth by Hypoxia and CTGF

在上一次授权期内，我们获得了结缔组织生长的表达 结缔组织生长因子(CTGF)在人胰腺肿瘤中升高，但在正常胰腺或胰腺炎中不升高。自.以来 胰腺肿瘤是高度低氧的，CTGF是众所周知的低氧诱导的，我们已经关注了这一点 了解缺氧和CTGF在胰腺肿瘤进展中的作用。这些的基础是 研究CTGF在胰腺肿瘤进展中的作用 证明用一种单抗特异性抗体靶向抑制CTGF可显著 两种不同胰腺癌细胞皮下移植瘤的生长抑制作用。在这 竞争性更新，项目1将侧重于确定CTGF及其个人的机械作用 常氧和低氧条件下胰腺肿瘤进展的区域。我们的初步数据 提示CTGF具有促进胰腺癌细胞生长的作用。CTGF的诱导没有 对塑料上的细胞生长有影响，但显著促进软琼脂中的球体生长。最引人注目的是 CTGF表达诱导的细胞黏附增加。这些细胞黏附的变化是必要的 导致我们检验了CTGF在恶性进展中的主要作用之一的假设 来调节细胞间的黏附，抑制这种活性会影响肿瘤的生长和转移。因此， 本研究的目的是：1)研究CTGF对胰腺癌细胞黏附的影响。 在细胞中使用区域特异性缺失突变体的常氧和低氧条件，这些突变体被操纵以 表达不同水平的HIF-1(项目3)，2)确定CTGF对3D生长和 常氧和低氧条件下的侵袭，3)抑制CTGF介导的黏附 影响转移生长，4)确定CTGF抑制细胞黏附如何影响皮下和 胰腺肿瘤细胞的原位肿瘤生长，并与项目4头颈部肿瘤合作， 5)确定间质和肿瘤细胞CTGF在肿瘤生长中的作用，6)确定 CTGF单抗与新型缺氧特异性细胞毒素PR-104联合应用控制胰腺肿瘤 与CTGF单抗和吉西他滨相比的生长(项目2)。总括而言，建议进行的研究包括 目的是阐明CTGF影响肿瘤进展的一个重要机制 并确定在联合治疗中将胰腺癌带到 诊所。

During the last grant period, we have obtained evidence that the expression of connective tissue growth factor (CTGF) is elevated in human pancreatic tumors, but not in normal pancreas or pancreatitis. Since pancreatic tumors are highly hypoxia and CTGF is known to be hypoxia inducible, we have focused this grant to understand the role of hypoxia and CTGF in pancreatic tumor progression. The basis for these studies to investigate the importance of CTGF in pancreatic tumor progression derive from our demonstration that targeted inhibition of CTGF with a monoclonal specific antibody results in significant growth inhibition of two different pancreatic cancer cell lines implanted as subcutaneous tumors. In this competitive renewal, Project 1 will focus on determining the mechanistic role of CTGF and its individual domains on pancreatic tumor progression under normoxic and hypoxic conditions. Our preliminary data suggests that CTGF is able to enhance the growth of pancreatic tumor cells. Induction of CTGF had no effect on cell growth on plastic, but significantly enhanced spheroid growth in soft agar. Most striking was the increase in cell adhesion induced by CTGF expression. These changes in cell adhesion that are necessary for 3-D growth lead us to test the hypothesis that one of the major roles of CTGF in malignant progression is to regulate cell-cell adhesion, and that inhibiting this activity will impact tumor growth and metastases. Thus, the aims of this proposal are to 1) determine how CTGF affects cell adhesion of pancreatic tumor cells under normoxic and hypoxic conditions using domain specific deletion mutants in cells that are manipulated to express different levels of HIF-1 (Project 3), 2) determine how important CTGF is for 3-D growth and invasion under normoxic and hypoxic conditions, 3) determine how inhibition of CTGF mediated adhesion affects metastatic growth, 4) determine how inhibition of cell adhesion by CTGF affects subcutaneous and orthotopic tumor growth of pancreatic tumor cells and in collaboration with Project 4 head and neck tumors, 5) determine the role of stromal and tumor cell CTGF on tumor growth, 6) determine how effective the combination of CTGF Ab and the new hypoxic specific cytotoxin PR-104 are in controlling pancreatic tumor growth compared to CTGF Ab and gemcitabine (Project 2). In summary, the proposed studies are intended to address an important mechanism by which CTGF affects tumor progression in pancreatic cancers and to determine how effective it is in combination therapy to bring it to the clinic.