Sex-Dependent PTHrP Processing and Lung Cancer Survival

描述(由申请人提供)： 甲状旁腺激素相关蛋白(PTHrP)是一种经过翻译后加工的多功能分子，是一种在50-75%的肺癌中表达的癌蛋白。治疗过程对患者的预后有重要影响。从我们以前的工作中，我们知道，在非小细胞肺癌(NSCLC)中，肿瘤羧基末端PTHrP的表达本身是一个积极的预后指标，而处理为单独的氨基末端PTHrP与患者较短的生存期相关。有趣的是，女性肺癌可能只表达羧基甲状旁腺素rP，只有女性患者在表达这一结构域时才表现出生存优势。相比之下，男性癌症通常包含两个PTHrP表位，并不显示出对生存的好处。因此，基于性别的氨基和羧基末端PTHrP相对表达的差异导致了性别相关的结局差异。来自小鼠肺癌模型的初步数据表明，睾丸激素控制着氨基和羧基PTHrP的性别差异。作为一个假设，我们提出，氨基和羧基末端PTHrP的相对表达是由于性类固醇而在男性和女性癌症中不同的加工过程的函数。此外，氨基和羧基PTHrP分别通过刺激和抑制肺癌细胞的生长、存活和侵袭作用直接调节肿瘤的进展。目的1建立雄激素对14种不同肺癌细胞系、同基因或免疫缺陷小鼠原位肺癌和新鲜人类肺癌中PTHrP加工的影响。这些研究将考虑与组织学、性别、吸烟史、共同突变状态、重要分子驱动因素和其他协变量的相互作用。加工过程将通过区域特异性免疫分析、体外PTHrP蛋白分解分析和质谱仪进行评估。目的2将确定PTHrP处理对小鼠肺癌进展的调节作用。实验将研究PTHrP形式，这些形式已经通过基因截断来处理，以缺少氨基或羧基PTHrP结构域。其他实验将研究耐受关键加工步骤的PTHrP突变体。目的3将确定调节雄激素依赖的PTHrP过程的蛋白水解酶及其对肿瘤进展的相关影响。这些实验将使用基于活性的探针来分离和测序受雄激素调控的蛋白酶。随后的实验将证实这些蛋白酶在PTHrP加工中的作用。该项目的翻译效益将来自于了解激素途径如何影响肺癌中氨基PTHrP和羧基PTHrP之间的平衡，并确定介导这些影响的蛋白酶。可以在针对雄激素调节途径或蛋白酶的药物中寻求新的、改进的治疗方法，以增加羧基PTHrP相对于氨基PTHrP并延长生存期。这一目标可能接近实现，因为我们已经发现了单独的环胍化合物，这是一类已知对丝氨酸蛋白酶活性有影响的分子，可以减少肺癌中的氨基PTHrP。

DESCRIPTION (provided by applicant): Parathyroid hormone-related protein (PTHrP), an oncoprotein expressed in 50-75% of human lung carcinomas, is a multifunctional molecule that undergoes post-translational processing. Processing has significant implications for patient outcome. From our previous work, we know that tumor expression of carboxyl-terminal PTHrP by itself is a positive prognostic indicator in women with non-small cell lung carcinoma (NSCLC), while processing to solely amino-terminal PTHrP is associated with shorter patient survival. Interestingly, lung carcinomas in females are likely to express carboxyl PTHrP alone and only female patients demonstrate a survival benefit from when expressing this domain. In contrast, carcinomas in males usually contain both PTHrP epitopes and do not show a survival benefit. Thus, a sex-based difference in relative expression of amino and carboxyl-terminal PTHrP contributes to a sex-dependent difference in outcome. Preliminary data from a mouse lung cancer model suggest that testosterone controls the sex difference in amino and carboxyl PTHrP. As a hypothesis, we propose that the relative expression of amino- and carboxyl-terminal PTHrP is a function of processing that varies between male and female carcinomas because of sex steroids. Furthermore, amino and carboxyl PTHrP regulate tumor progression directly through stimulatory and inhibitory effects, respectively, on lung cancer cell growth, survival and invasiveness. Aim 1 will establish the effects of androgens on processing of PTHrP in lung carcinoma in over 14 different lung cancer cell lines, in orthotopic lung carcinomas in syngeneic or immunocompromised mice, and in fresh human lung carcinomas. The studies will consider interactions with histology, sex, smoking history, mutational status in common, important molecular drivers and other covariates. Processing will be assessed by region-specific immunoassay, in vitro PTHrP proteolysis assays and mass spectrometry. Aim 2 will define the regulatory effects of PTHrP processing on lung carcinoma progression in the mouse models. Experiments will study PTHrP forms that have been processed by gene truncation to lack amino or carboxyl PTHrP domains. Additional experiments will study PTHrP mutants resistant to key processing steps. Aim 3 will identify proteases that regulate androgen-dependent PTHrP processing and the associated effects on tumor progression. The experiments will use activity-based probes to isolate and sequence proteases regulated by androgens. Subsequent experiments will confirm the role of these proteases in PTHrP processing. The translational benefit of this project will result from learning how hormonal pathways affect the balance between amino PTHrP and carboxyl PTHrP in lung cancer and identifying the proteases mediating those effects. Novel, improved treatments could be sought in drugs that targeted the androgen regulatory pathway or the proteases to augment carboxyl PTHrP relative to amino PTHrP and prolong survival. This goal may be close to fruition because we have found individual cyclic guanidine compounds , a class of molecule with known effects on serine protease activity, that reduce amino PTHrP in lung cancer.