Regulation of multiple angiogenic signaling and development of cancer-specific gene therapy

我们之前报道过血管生成素（Angiopoietin, Ang），一种Tie2血管内皮特异性受体酪氨酸激酶的配体，可能在人类肝细胞癌（HCC）的进展中发挥作用，HCC通常以快速生长的高血管肿瘤为特征（J clininvest 1999）和基质蛋白酶表达（Cancer Res 2001）。然而，Tie2受体在肝癌发生中的作用尚不清楚。免疫组化结果显示，Tie2受体蛋白在31/39（80%）人肝癌肿瘤的新生血管内皮中过表达，且与细胞去分化和肿瘤大小有显著相关性（p<0.05）。在体外表达含有可溶性Tie2外结构域（sTie2）的显性阴性构建体，导致Ang蛋白相互作用，抑制血管内皮细胞内源性Tie2磷酸化，抑制基质金属蛋白酶-9 （MMP-9）。体内基因转移和肝细胞癌模型中sTie2的表达抑制了肝细胞癌新生血管形成的致瘤性。更多尿液肝细胞癌模型表明，Tie2表达可能在肝细胞癌新生血管形成和疾病进展中起作用（《肝病》杂志）。更重要的是，抑制Ang/Tie2信号转导级联是一种很有前途的肿瘤治疗方法。通过靶向差异显示，我们发现了CCN家族成员WISP1 （wnt诱导分泌蛋白1）的一种新变体，命名为WISP1v，在硬膜性胃癌中过度表达。新出现的CCN基因家族成员（用于结缔组织生长因子，富含半胱氨酸61，肾母细胞瘤过度表达）编码富含半胱氨酸的分泌蛋白，在人类纤维化疾病和癌症血管生成中发挥作用。预测的WISP1 v蛋白完全缺乏被认为参与蛋白复合物形成的Von Willebrand C型模块。异位表达表明WISP1 v是一种分泌的癌蛋白，可诱导显著的细胞转化和快速堆积生长。值得注意的是，WISP1 v转染物增强了共培养胃癌细胞的侵袭性表型，而野生型WISP1则没有这种潜力。这些发现提示CCN蛋白WISP1 v参与了黏液性胃癌的侵袭性进展。少

We have previously reported that Angiopoietin (Ang), a ligand for Tie2 vascular endothelial-specific receptor tyrosine kinase, may play a role in the progression of human hepatocellular carcinoma (HCC) is generally characterized as a hypervascular tumor of rapid growth (J Clin Invest 1999) and matrix proteinase expression (Cancer Res 2001). However, the role of Tie2 receptor in hepatic oncogenesis is unknown. The Tie2 receptor protein was overexpressed in the neovascular endothelium of 31/39 (80%) human HCC tumors by immunohistochemical analysis with significant correlation to cell dedifferentiation and tumor size (p<0.05). In vitro expression of a dominant-negative construct, containing a soluble Tie2 ectodomain (sTie2), led to Ang protein interaction, inhibition of endogeneous Tie2 phosphorylation in vascular endothelial cells, and matrix metalloproteinase-9 (MMP-9) suppression. Tumorigenicity with neovascularization was suppressed by in vivo gene transfer and sTie2 expression in a m … More urine HCC model suggesting a possible role for Tie2 expression in the induction of HCC neovascularization, and disease progression (Hepatology (in press)). More important, inhibition of the Ang/Tie2 signal transduction cascade is a promising approach for tumor treatment.Using targeted differential displays, we identified a novel variant of the CCN family member WISP1 (Wnt-induced secreted protein 1), named WISP1v, as overexpressed in scirrhous gastric carcinomas. Members of the emerging family of the CCN gene (for connective tissue growth factor, cysteine-rich 61, nephroblastoma overexpressed) encode cysteine-rich secreted proteins with roles in human fibrotic disorders and cancer angiogenesis. Predicted protein of the WISP1 v completely lacks a module of Von Willebrand type C that is thought to participate in protein complex formation. Ectopic expression revealed WISP1 v to be a secreted oncoprotein inducing a striking cellular transformation and rapid piling-up growth. It is noteworthy that WISP1 v transfectants enhanced the invasive phenotype of co-cultured gastric carcinoma cells, while wild-type WISP1 had no such potential. These findings suggest that CCN protein WISP1 v is involved in the aggressive progression of scirrhous gastric carcinoma. Less