Targeting alfa 1beta1 integrin in cancer development

描述（申请人提供）：实体瘤的生长高度依赖于血管生成。在这种新血管形成过程中，在内皮细胞上表达的整合素是重要的介质。抑制这些整合素的功能是目前癌症研究的方向之一。此外，癌细胞上表达的整合素参与这些细胞在转移期间的迁移。在拟议的研究计划中，我们将研究ct 1131整联蛋白（VLA-1），它被认为是一种特异性的IV型胶原受体。我们将重点研究VLA-1的两种抑制剂obtustatin和viperisrastatin。它们都属于去整合素家族，并且是VLA-1的低分子量抑制剂（4.2kDa）。这些去整合素的活性已经定位在其整合素结合环内作为活性序列KTS。Obtustatin在体内鸡CAM模型和体外试管EC形成试验中显示出有效的血管抑制活性。此外，obtustatin在同基因小鼠模型中抑制刘易斯肺癌的发展。KTS-去整合素的活性将在由小鼠黑色素瘤B 16和M-3细胞系在同基因小鼠中诱导的生长肿瘤上以及人黑色素瘤细胞系MV 3、HS. 939 T、A-375、C32和A2058在裸鼠中诱导的生长肿瘤上进一步测试。VLA-1参与这些细胞系向肺的转移将使用同基因小鼠和裸鼠在体内进行研究。为了解释含去整合素的KTS的血管抑制作用的机制，将进行一系列实验来研究它们对微血管EC的影响。初步数据表明，obtustatin诱导这些细胞的凋亡，并抑制其增殖。基于先前的报告表明VLA-1参与依赖于MAPK的信号转导途径，将评价KTS-去整合素对该途径活化的影响。此外，将提出胶原凝胶中的径向迁移测定。该体外试验模拟了基底膜溶解后新生血管形成早期EC的运动。将测试这两种去整合素在该模型中EC运动性中的作用。Obtustatin及其天然存在的类似物viperisrastatin可能是设计合成或重组化合物的模型，这些化合物可能用于癌症治疗。总之，含去整合素的KTS的工作可能导致更好地理解VLA-1参与癌症进展和转移，以及有助于理解VLA-1在血管生成中的作用。

DESCRIPTION (provided by applicant): The growing of solid tumors highly depends on angiogenesis. In this new vessel formation process the integrins, expressed on endothelial cells are important mediators. Inhibition of function of these integrins is currently one of the directions in cancer research. Moreover, integrins expressed on cancer cells are involved in migration of these cells during metastasis. In the proposed research plan, we will investigate ct 1131 integrin (VLA-1), which is recognized as a specific collagen IV receptor. We will focus our research on two inhibitors of VLA-1, obtustatin and viperisrastatin. Both of them belong to disintegrin family, and are low molecular mass inhibitors (4.2 kDa) of VLA-1. The activity of these disintegrins has been localized within their integrin-binding loop as an active sequence KTS. Obtustatin showed potent angiostatic activity in the chicken CAM model in vivo, and in tube EC formation assay in vitro. Moreover, obtustatin inhibited Lewis lung cancer development in syngeneic mouse model. The activity of KTS-disintegrins will be further tested on growing tumor induced by mouse melanoma B 16 and M-3 cell lines in the syngeneic mouse, and human melanoma cell lines, MV3, HS.939T, A-375, C32, and A2058 in nude mice. The participation VLA-1 in metastasis of these cell lines to the lung will be investigated in vivo using syngeneic and nude mice. To explain the mechanism of the angiostatic effect of KTS containing disintegrins, series of experiments will be performed to investigate their effect on microvascular EC. The preliminary data showed that obtustatin induced apoptosis in these cells and inhibited their proliferation. Based on the previous reports indicating involvement of VLA-1 in signal transduction pathway dependent on MAPK, the effect of KTS-disintegrins on activation of this pathway will be evaluated. Moreover, radial migration assay in collagen gel will be proposed. That in vitro assay imitates movement of EC during early stage of neovascularization after dissolution of the basement membrane. The effect of both disintegrins in EC motility in this model will be tested. Obtustatin and its naturally occurring analog viperisrastatin may be models for designing of synthetic or recombinant compounds, which may be useful in cancer therapy. In summary, the work with KTS containing disintegrins may lead to the better understanding of the involvement of VLA-1 in cancer progression and metastasis, as well as contribute to an understanding of the role of VLA-1 in angiogenesis.