Screen for inhibitors of STK-33 kinase activity

描述（由申请人提供）：小gtpase的RAS家族突变约占人类肿瘤的30%。尽管在过去的25年里RAS的研究非常活跃，但事实证明，RAS的直接抑制剂的鉴定具有挑战性，需要其他方法来调节RAS的活性。一种这样的方法利用突变ras依赖细胞对非致癌细胞因子的明显依赖性。例如，丝氨酸/苏氨酸激酶STK33最近被RNAi技术证明是kras依赖性突变癌细胞存活和增殖所必需的，而不是kras独立型细胞。这些结果表明突变体KRAS和STK33之间存在共同依赖性，从而导致STK33被抑制后的合成致死相互作用。本提案的总体目标是鉴定一组直接的STK33激酶活性抑制剂，这些抑制剂可以概括RNAi在诱导kras依赖性突变细胞凋亡的精细细胞特异性，而对kras非依赖性细胞没有明显的影响。该提案的具体目标是：(1)在一个强大的、敏感的、先前经过验证的初级筛选中鉴定STK33激酶活性抑制剂，(2)利用一组基于二级细胞的检测来选择那些特异性靶向突变kras依赖性细胞的STK33抑制剂，以及(3)实现一个关键路径来促进探针的优化和开发。该研究计划的长期目标是利用这些STK33特异性探针与综合蛋白质组学方法相结合，阐明ras依赖性调节和突变kras依赖性肿瘤发生的分子基础，目标是将这些知识转化为治疗机会。

DESCRIPTION (provided by applicant): Mutations in the RAS family of small GTPases are responsible for approximately 30% of human tumors. Despite intense activity over the last 25 years, the identification of direct inhibitors of RAS has proven challenging, necessitating alternative approaches to modulating RAS activity. One such approach takes advantage of the apparent dependency of mutant RAS-dependent cells on non-oncogenic cellular factors. For instance, the serine/threonine kinase, STK33, has recently been shown by RNAi techniques to be required for the survival and proliferation of mutant KRAS-dependent cancer cells, but not KRAS-independent cells. These results indicate a co-dependency between mutant KRAS and STK33 that results in a synthetic lethal interaction upon suppression of STK33. The overall goal of this proposal is to identify a set of direct STK33 kinase activity inhibitors that can recapitulate the exquisite cell-based specificity of RNAi for inducing apoptosis in mutant KRAS-dependent cells without discernable effects on KRAS-independent cells. The specific aims of this proposal are to (1) identify STK33 kinase activity inhibitors in a robust, sensitive, previously validated primary screen, (2) utilize a panel of secondary cell-based assays to select for those STK33 inhibitors that specifically target mutant KRAS-dependent cells, and (3) implement a critical path to facilitate probe optimization and development. The longer term objective of this research program is to utilize these STK33- specific probes in conjunction with a comprehensive proteomics approach to elucidate the molecular basis of RAS-dependent regulation and mutant KRAS-dependent tumorigenesis with the goal of translating this knowledge into a therapeutic opportunity. PUBLIC HEALTH RELEVANCE: The overall goal of this research is to identify chemical probes that will inform us about how the most common mutation occurring in human tumors causes cancer. This knowledge along with these chemical probes as lead structures can then be used to generate novel therapeutic opportunities.