Identification of small molecule activators of procaspase-7 to caspase-7

描述（由申请人提供）：癌症的一个标志是能够逃避程序性细胞死亡或凋亡；这允许不受控制的增殖和肿瘤生长。我们的目标是通过靶向凋亡通路中的关键蛋白：executioner procaspase，利用一种小分子来激活并触发癌细胞的凋亡。我们希望开发出一种个性化的癌症治疗策略，用专门的小分子治疗procaspase水平升高的癌症。众所周知，在某些癌症中，如前列腺癌，procaspase-7水平升高。我们假设，通过直接将procaspase-7转化为caspase-7的小分子激活剂，可以选择性地诱导含有高水平procaspase-7的癌细胞凋亡。我们小组最近的研究支持了这一假设，我们能够通过小分子激活procaspase-3到caspase-3来诱导癌细胞凋亡。

DESCRIPTION (provided by applicant): One hallmark of cancer is the ability to evade programmed cell death, or apoptosis; this allows uncontrolled proliferation and tumor growth. Our goal is to use a small molecule to activate to trigger apoptosis in cancer cells by targeting key proteins in the apoptotic pathway: executioner procaspases. We hope to develop a strategy for personalized cancer treatment in which cancers with elevated levels of procaspases will be treated with specialized small molecules. It is known that there are elevated levels of procaspase-7 in certain cancers, such as prostate cancer. We hypothesize that apoptosis can be selectively induced in cancer cells containing elevated levels of procaspase-7 via a direct small molecule activator of procaspase- 7 to caspase-7. This hypothesis is supported by recent research in our group in which we were able to induce apoptosis in cancer cells by small molecule activation of procaspase-3 to caspase-3. Specific Aim 1. Identification of small molecules which activate procaspase-7 to caspase-7. In this specific aim we intend to A) perform timecourse analyses to elucidate how procaspase-7 activates over time, B)identify a small molecule activator of procaspase-7 from a library screen, and C) validate procaspase-7-activating compounds found in the library screen. Specific Aim 2. Induction of apoptotic death using the identified small molecule activator of procaspase-7. During apoptosis, cells display a variety of characteristic traits. We will use various techniques to monitor the apoptotic hallmarks in HL60 and MCF-7 cells induced by the identified small molecule in Specific Aim 1. Techniques include Flow cytometry to detect phosphatidyl serine exposure on apoptotic cell membranes, Hoescht staining to detect chromatin condensation in apoptotic cells, Rescue from apoptotic death with a pan-caspase inhibitor Specific Aim 3. Identification of specific cancers in which executioner procaspase levels are elevated. A variety of paraffin-embedded primary cancer tissues are available to the Hergenrother laboratory. Using Western blotting and immunohistochemistry, we can determine executioner procaspase-3, -6, and -7 levels in prostate and breast cancer tissues.