【作者】 杨旭；

【导师】 林德贵； Hong Wang； Chung S. Yang；

【作者基本信息】 中国农业大学 ， 临床兽医学， 2017， 博士

【摘要】 背景:乳腺肿瘤是女性第一大癌症,也是母犬身上最常见的肿瘤病。而肿瘤转移是导致乳腺癌患者死亡的最主要原因。胞外核苷酸酶CD73在癌症转移等发展过程发挥重要的作用。研究表明,CD73能够促进乳腺癌的生长以及转移等过程。因此,CD73靶向抑制剂能够为乳腺癌提供一种有效的治疗方案。研究发现泰妙菌素在体外能够抑制CD73的活性。因此,本课题研究了泰妙菌素能否对乳腺癌产生抑制作用,并分析了可能存在的相关机制。此外,前列腺癌是威胁男性生命和健康的重大癌症之一。生育酚对包括前列腺癌在内的多种类型的癌症都有预防作用,而δ-生育酚在前列腺癌细胞中会抑制AKT的活化。因此,我们利用PTEN-/-小鼠研究了 δ-生育酚在体内对前列腺癌的预防作用。方法:(1)通过检测MDA-MB-231和4T1乳腺癌细胞系的细胞活性、细胞克隆形成试验、细胞迁移和侵袭试验、酶活试验以及Western-blot等技术研究了泰妙菌素对CD37蛋白表达和活性的影响,以及对乳腺癌细胞增殖、迁移和侵袭的影响。(2)通过乳腺肿瘤小鼠模型的建立,测量乳腺肿瘤的生长体积和重量以及免疫组化检测等试验研究了泰妙菌素对乳腺肿瘤生长和转移的影响,并分析了可能存在的相关机制。(3)通过建立PTEN-/-小鼠前列腺癌模型,前列腺组织病理学诊断以及免疫组化检测等试验研究了δ 生育酚对pAKT蛋白水平的影响以及对前列腺癌发生发展的影响,并分析了可能存在的相关机制。结果:(1)泰妙菌素抑制CD73的活性但并不影响其表达,泰妙菌素通过CD73抑制乳腺癌细胞的生长、迁移和侵袭。(2)泰妙菌素抑制小鼠体内乳腺肿瘤的生长和肺转移,并且抑制肿瘤组织中新生血管的形成。(3)δ-生育酚降低了前列腺组织中pAKT、Ki67的水平,并且降低了前列腺中发生癌变的腺体的数量。结论:(1)泰妙菌素通过降低CD73的活性来抑制乳腺癌的生长以及肿瘤的肺部转移。(2)δ-生育酚对前列腺癌的预防作用与降低pAKT的活化水平有关。更多还原

【Abstract】 Background:Breast cancer is the most frequent cancer in women,as well as in bitches.Metastasis is the leading cause of death in breast cancer patients.CD73,also known as ecto-5’-nucleotidase,plays a vital role in cancer development including metastasis.The existing researches indicate that overexpression of CD73 promote growth and metastasis of breast cancer.Therefore,CD73-targeted inhibitor can offer a promising treatment for breast cancer.Here,we determined whether tiamulin,which was found to inhibit CD73,was able to suppress breast cancer development and the related mechanisms.Prostate cancer is one of the most common cancers in male.Tocopheral was reported to prevent various types of cancer,including prostate cancer,and δ-tocopheral was shown to decrease pAKT level in prostate cancer cell.We studied the prostate cancer preventive activity of δ-tocopheral using PTEN-/-mice.Methods:(1)The effect of tiamulin hydrogen fumarate(THF)on CD73 was determined by high performance liquid chromatography(HPLC).Then,the cell proliferation,migration and invasion were investigated in MDA-MB-231 human breast cancer cell line and 4T1 mouse breast cancer cell line treated with THF by migration assay,invasion assay and activity assay.(2)The effect of THF on allograft mammary tumors of mice was examined by tumor volume and weight measurement,and immunohistochemistry.(3)The effect of δ-tocopheral on prostate cancer in PTEN-/-mice was examined by histopathology and and immunohistochemistry.Results:(1)Our data demonstrated that THF inhibited CD73 by decreasing the activity instead of the expression of CD73.In vivo,THF inhibited the proliferation,migration and invasion of MDA-MB-231 and 4T1 cells by suppressing CD73 activity.(2)In vivo,allograft experiments showed that THF treatment resulted in significant reduction in allograft tumor growth,microvascular density and lung metastasis rate.(3)PTEN-/-mice model showed that δ-tocopheral reduced the level of pAKT and Ki67,and also decreasing the number of prostate glands containing adenocarcinoma.Conclusion:(1)Our results indicate that THF inhibit growth and metastasis of breast cancer by blocking the activity of CD73,which may offer a promising treatment for breast cancer therapy.(2)Our results indicate that δ-tocopheral prevent prostate cancer might by decreasing the level of pAKT.更多还原