DIET,APOPTOSIS AND COLON CARCINOGENESIS

饮食、细胞凋亡和结肠癌发生

• 批准号: 6698029
• 负责人: JOANNE R LUPTON
• 金额: $ 32.74万
• 依托单位: TEXAS A&M UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2007-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6698029
• 关键词: apoptosis; butyrates; cardiolipins; cell differentiation; cell proliferation; chemical carcinogen; chemical carcinogenesis; colon neoplasms; cyclin dependent kinase; cyclins; dietary lipid; dietary supplements; enzyme activity; enzyme inhibitors; free radical oxygen; immunocytochemistry; laboratory rat; marine animal oil; mitochondria; nutrition aspect of cancer; nutrition related tag; prostaglandin endoperoxide synthase; vegetable oils

DESCRIPTION: Others and we have shown that fish oil vs corn oil, is protective against experimentally-induced colon cancer. Recently we reported that this protective effect is due to a higher steady state level of apoptosis with fish oil supplementation. In addition, we show a synergistic protective effect of the combination of fish oil and pectin (a highly fermentable fiber) on both tumor incidence and enhancement of spontaneous apoptosis. We now show data that the combination of fish oil and pectin also enhances targeted apoptosis within the first 12 hours after administration of the carcinogen azoxymethane (AOM). The overall goal of this proposal is to understand, at a mechanistic level, how fish oil, high in n-3 fatty acids, induces apoptosis in colonocytes and thus protects against experimentally-induced colon tumorigenesis. A secondary goal is to determine how supplementing fish oil-containing diets with pectin compared to cellulose synergistically enhances the protective effect of fish oil. Hypotheses: The observed enhancement of apoptosis with fish oil supplementation is due to (1) down regulation of Cox-2 expression providing a permissive environment for butyrate-induced apoptosis; and/or (2) alterations in mitochondrial function which are permissive for butyrate-induced apoptosis. To test these hypotheses we have three specific aims: 1. Determine in vivo expression of Cox-2, apoptosis, p21waf1/CipI p27kip1, Cyclin Dl, cell proliferation and differentiation as a function of dietary lipid, butyrate, and carcinogen administration, during the stage of promotion. Using a 3 x 2 x 2 factorial design (fish oil, fish oil ethyl esters, or corn oil supplementation; plus or minus butyrate; saline or AOM), we will use quantitative immunohistochemistry on serial sections of rat colon to detect patterns of expression of Cox-2, apoptosis, p21 WAFI/CIPI and Cyclin Dl; and p27Kip1 differentiation, and apoptosis in the same cells. 2. Determine in vivo expression of the same markers as in specific aim #1, as a function of dietary lipid, butyrate, and AOM, but during the initiation stage of colon cancer. 3. Determine in an ex vivo system if fish oil alters mitochondrial function thus creating a permissive environment for butyrate-induced apoptosis. Using a 3 x 2 factorial design (fish oil; fish oil ethyl esters or corn oil; saline or AOM), during the stage of promotion we will determine the effect on known indicators of mitochondrial function, reactive oxygen species, cardiolipin fatty acid composition and butyrate-induced apoptosis. An understanding of how diet affects colon tumor incidence has important consequences for the design of clinical trials and for future dietary recommendations.

描述：其他人和我们已经表明，鱼油与玉米油，是保护 对抗实验诱发的结肠癌最近我们报道说， 保护作用是由于鱼的细胞凋亡的更高的稳态水平 补充油。此外，我们还显示了协同保护作用， 鱼油和果胶（一种高度发酵的纤维）的组合， 肿瘤发生率和自发凋亡增强。我们现在的数据显示， 鱼油和果胶的组合还增强了细胞内的靶向细胞凋亡， 致癌物氧化偶氮甲烷（AOM）给药后的前12小时。 本提案的总体目标是在机械层面上了解如何 富含n-3脂肪酸的鱼油可诱导结肠细胞凋亡， 防止实验诱导的结肠肿瘤发生。次要目标 是为了确定如何在含鱼油的饮食中补充果胶 与纤维素相比， 油假设：观察到的鱼油对细胞凋亡的增强作用 补充是由于（1）下调考克斯-2表达， 丁酸盐诱导的细胞凋亡的容许环境;和/或（2）改变 在线粒体功能中，其允许丁酸盐诱导的细胞凋亡。 为了验证这些假设，我们有三个具体目标：1。确定体内 考克斯-2表达，凋亡，p21 waf 1/CipI，p27 kip 1，细胞周期蛋白D1，细胞 增殖和分化作为膳食脂质、丁酸盐和 致癌物管理，在促进阶段。使用3 x 2 x 2 析因设计（鱼油、鱼油乙酯或玉米油补充剂; 加或减丁酸盐;生理盐水或AOM），我们将使用定量 免疫组织化学方法检测大鼠结肠连续切片中 考克斯-2、细胞凋亡、p21 WAFI/CIPI和细胞周期蛋白D1的表达;以及p27 Kip 1 分化和凋亡。2.确定体内 表达与具体目标#1中相同的标志物，作为饮食的函数， 脂质，丁酸盐和AOM，但在结肠癌的起始阶段。3. 在离体系统中确定鱼油是否改变线粒体功能， 为丁酸盐诱导的细胞凋亡创造一个允许的环境。使用3x 2 析因设计（鱼油;鱼油乙酯或玉米油;盐水或AOM）， 在推广阶段，我们将确定对已知指标的影响 线粒体功能，活性氧，心磷脂脂肪酸 组成和丁酸诱导的细胞凋亡。了解饮食 影响结肠肿瘤的发病率对设计 临床试验和未来的饮食建议。