Role of Hydrogen Sulfide in Colorectal Tumors

描述(申请人提供)：这项修订的拨款申请集中在内源性气态生物介体硫化氢(硫化氢)在结直肠癌中的作用。基于一系列新的数据，我们提出了一个新的假设，即结肠癌细胞中胱硫醚合成酶(CBS)的选择性上调和随后的硫化氢的产生通过刺激肿瘤细胞的生物能量学、生长、增殖、迁移和侵袭，作为促进生存的因素。为了探讨这一概念，我们将继续 目的：1.研究CBS/H_2S轴促进肿瘤细胞生物能量学和肿瘤细胞增殖的分子机制；#2.确定CBS/H_2S轴促进肿瘤细胞迁移、侵袭和转移的分子机制；#3.在患者来源的异种移植物(PDTX)与当前临床抗癌治疗药物联合使用的翻译相关动物模型中，评价CBS抑制剂氨基氧乙酸(AOAA)在人类结直肠癌中的作用。综上所述，目前的项目将利用人结肠癌组织、人结肠癌细胞系和携带肿瘤的小鼠进行人结肠癌细胞系或患者来源的异种移植。为了解决CBS的作用，将使用遗传学(CBS沉默)和药理学(CBS抑制剂)相结合的方法。结果变量将包括生物能量学参数(氧化磷酸化、线粒体电子传递、糖酵解、GAPDH活性)、细胞增殖、细胞生长(包括Pr-炎症/促生长激酶通路的激活)、肿瘤细胞迁移、肿瘤细胞侵袭、血管生成和体外和体内转移。硫水化(一种特定的硫化氢介导的翻译后蛋白质修饰)在相关蛋白质靶标(GAPDH、PTEN、PI3K)上的作用也将被探索。最终的翻译目标将包含潜在的治疗相关性研究，通过测试CBS抑制剂的抗癌效果，综上所述，本项目需要一种全面的方法来测试CBS/H2S在结直肠癌中的新途径的重要性，并结合早期的翻译工作来探索其作为抗癌治疗靶点的潜在效用。

DESCRIPTION (provided by applicant): This revised grant application focuses on the role of the endogenous gaseous biological mediator hydrogen sulfide (H2S) in colorectal cancer. Based on multiple lines of novel data, we have developed the novel hypothesis that selective upregulation of cystathionine-¿-synthase (CBS) and the subsequent production of H2S in colonic cancer cells serves as a pro-survival factor by stimulating tumor cell bioenergetics, growth, proliferation, migration and invasion. In order to explore this concept, we will pursue the following Aims: #1. To characterize the molecular mechanisms by which the CBS/H2S axis promotes tumor cell bioenergetics and tumor cell proliferation; #2. To determine the molecular mechanisms by which the CBS/H2S axis promotes tumor cell migration, invasion and metastasis; and #3. To evaluate the effect of the CBS inhibitor aminooxyacetic acid (AOAA) in human colorectal cancer, in a translationally relevant animal model utilizing patient-derived xenografts (PDTX) in combination with current clinical anticancer therapeutic agents. Taken together, the current project will utilize human colonic cancer tissues, human colonic cancer cell lines and tumor-bearing mice subjected to heterotopic transplantation of human colon cancer lines or patient-derived xenografts. To address the role of CBS, a combination of genetic (CBS silencing) and pharmacological (CBS inhibitors) approaches will be used. Outcome variables will include parameters of bioenergetics (oxidative phosphorylation, mitochondrial electron transport, glycolysis, GAPDH activity), cell proliferation, cell growth (including activation of pr-inflammatory/pro-growth kinase pathways), tumor cell migration, tumor cell invasion, angiogenesis and metastasis in vitro and in vivo. The role of sulfhydration (a specific H2S-mediated posttranslational protein modification) will be also explored on relevant protein targets (GAPDH, PTEN, PI3K). The final, translational aim will contain studies of potential therapeutic relevance, by testing the anticancer effect of CBS inhibitors, in summary, the current project entails a comprehensive approach to test the importance of CBS/H2S a novel pathway in colorectal cancer, and incorporates early translational work to explore its potential utility as a target for anticancer therapy.