Regulation of Tumor and Metastatic Growth by Hypoxia and CTGF

在上一次资助期间，我们获得的证据表明，结缔组织生长的表达 CTGF在人胰腺肿瘤中升高，但在正常胰腺或胰腺炎中不升高。以来 胰腺肿瘤是高度缺氧的，并且已知CTGF是缺氧诱导的，我们将重点放在 授予了解缺氧和CTGF在胰腺肿瘤进展中的作用。这些的基础 研究CTGF在胰腺肿瘤进展中的重要性来自我们的 证明用单克隆特异性抗体靶向抑制CTGF导致显著的 作为皮下肿瘤植入的两种不同胰腺癌细胞系的生长抑制。在这 竞争性更新，项目1将重点确定CTGF及其个人的机械作用 在常氧和缺氧条件下，胰腺肿瘤进展的结构域。我们的初步数据 提示CTGF能够促进胰腺肿瘤细胞的生长。CTGF的诱导没有 影响塑料上的细胞生长，但显著促进软琼脂中的球状体生长。最引人注目的是 CTGF表达诱导的细胞粘附增加。这些细胞粘附的变化是必要的 三维生长的研究使我们验证了CTGF在恶性进展中的主要作用之一是 调节细胞-细胞粘附，抑制这种活性将影响肿瘤生长和转移。因此，在本发明中， 该建议的目的是：1）确定CTGF如何影响胰腺肿瘤细胞的细胞粘附， 在常氧和低氧条件下，在细胞中使用结构域特异性缺失突变体， 表达不同水平的HIF-1（项目3），2）确定CTGF对三维生长的重要性， 在常氧和缺氧条件下的侵袭，3）确定CTGF介导的粘附的抑制如何 影响转移性生长，4）确定CTGF对细胞粘附的抑制如何影响皮下， 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)确定基质和肿瘤细胞CTGF对肿瘤生长的作用，6）确定 CTGF Ab与新型缺氧特异性细胞毒素PR-104联合应用对胰腺肿瘤的治疗作用 与CTGF Ab和吉西他滨相比的生长（项目2）。总的来说，拟议的研究是 目的是解决CTGF影响肿瘤进展的重要机制， 胰腺癌，并确定它在联合治疗中的有效性， 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.