PTEN缺失在乳腺癌发生发展中的作用研究

发布时间：2018-07-25 13:09

【摘要】：目的:乳腺癌是异质性肿瘤,由于个体之间基因表达,环境因素、遗传因素等的差异性造成乳腺癌的复杂多样性。乳腺癌的异质性给肿瘤的治疗和预后带来极大的困难。乳腺癌的其中一个重要致病因素是癌症基因组发生改变。基因的改变也构成了乳腺癌病理和生理的多样性。pten基因是抑癌基因,编码具有双重磷酸酶活性的PTEN蛋白。研究表明大约50%左右的乳腺癌发生PTEN的缺失。许多研究报道,PTTEN缺失与乳腺癌的不良预后有关。本文探讨了 PTEN基因同乳腺癌发生发展和预后之间的联系,将为乳腺癌的治疗提供理论依据。方法:综合TCGA数据和meta荟萃分析PTEN缺失与乳腺癌的预后的关系。根据知情同意原则收集云南省昆华医院乳腺癌样品,通过免疫组化方法检测乳腺癌患者关键蛋白的表达。构建PTEN敲低的乳腺癌细胞系检测PTEN缺失对PI3K/AKT/mTOR和Raf/MEK/ERK信号通路的影响。结果:①TCGA数据表明,PTEN突变或PTEN缺失对乳腺癌患者生存没有显著影响。②meta分析发现PTEN缺失与Her2靶向治疗Her2阳性乳腺癌患者药物反应率有显著相关性(p0.001)。PTEN缺失与曲妥珠单抗靶向治疗Her2阳性乳腺癌患者总生存期有显著相关性(p=0.006)。PTEN缺失与曲妥珠单抗靶向治疗Her2阳性乳腺癌患者无病生存期无显著相关性(p=0.460)。③乳腺癌样品四种分子分型中Luminal A型患者有3例(6%)、Luminal B型患者4例(8%)、Her2阳性型患者23例(46%)、三阴性患者有20例(40%),其中淋巴结肿大患者为92.6%,淋巴结转移患者有51.9%,绝大部分患者组织分级为浸润型导管癌。④乳腺癌分子分型和Bcl2、P53、MMP9、PI3K 110α的表达量没有显著相关性。⑤乳腺癌样品中,PTEN蛋白的缺失达到70%。PTEN表达量与肿瘤直径、淋巴结肿大和淋巴结转移没有显著相关性。PTEN的表达量与ER、Ki67、MMP9的表达量有显著相关性(p0.05),但是PTEN的表达量与PR的表达量、Her2的表达量、Bcl2的表达量、P53的表达量、PI3K110α表达量无显著相关性(p0.05)。⑥Cas9质粒构建PTEN敲低的乳腺癌细胞系发现,PI3K/Akt/mTOR通路中,p-AKTThr308和p-AKT Ser473表达量升高,p-mTOR Ser2481和p-mTOR Ser2448表达量也明显升高。而在Raf/MEK/ERK信号通路中p-MEK1/2和p-ERK1/2表达量没有显著性差异。结论:TCGA数据分析表明PTEN低表达或PTEN缺失对乳腺癌患者的预后没有差异性影响,但是meta数据分析显示在对Her2靶向治疗的Her2阳性乳腺癌中,PTEN缺失预示不良的预后结果。免疫组化结果显示乳腺癌组织中PTEN缺失达到70%。乳腺癌组织中MMP9的表达量高达72%。在PTEN缺失的样本中迁移标志物MMP9阳性率也显著高于PTEN正常的样本,PTEN蛋白表达量与MMP9的表达量有显著相关性(p=0.028),PTEN缺失与MMP9高表达有密切联系,PTEN缺失的患者淋巴结转移比率和个数与PTEN正常的样本相比呈明显增高趋势。说明PTEN在乳腺癌中与肿瘤的迁移和侵袭有着密切的关系,PTEN可能作为乳腺癌浸润和转移的标志物之一。在PTEN敲低的乳腺癌细胞系中,PTEN缺失或低表达激活对PI3K/Akt/mTOR信号通路起激活的作用,对Raf/MEK/ERK信号通路没有显著影响。因此PTEN缺失可能在乳腺癌的发生发展和预后中起到关键作用。
[Abstract]:Objective: breast cancer is a heterogeneous tumor. The diversity of breast cancer is caused by the differences in gene expression, environmental factors and genetic factors among individuals. The heterogeneity of breast cancer brings great difficulties to the treatment and prognosis of the tumor. One of the important pathogenic factors of breast cancer is the change of the cancer genome. The pathological and physiological diversity of.Pten is also a tumor suppressor gene, which encodes a PTEN protein with double phosphatase activity. The study shows that about 50% of the breast cancer is missing in PTEN. Many studies have reported that the deletion of PTTEN is related to the poor prognosis of breast cancer. This paper discusses the development and development of the PTEN gene with breast cancer. The relationship between the prognosis will provide a theoretical basis for the treatment of breast cancer. Methods: TCGA data and meta meta analysis of the relationship between PTEN deletion and the prognosis of breast cancer. According to the principle of informed consent, the samples of breast cancer in Kunhua Hospital of Yunnan province were collected, and the expression of key protein in breast cancer patients was detected by immunohistochemical method. The PTEN knockout was constructed. The effects of PTEN deletion on PI3K/AKT/mTOR and Raf/MEK/ERK signaling pathways were detected. Results: (1) TCGA data showed that PTEN mutation or PTEN deletion had no significant influence on the survival of breast cancer patients. (2) meta analysis revealed a significant correlation between PTEN deletion and Her2 targeting therapy for Her2 positive breast cancer patients (p0.001).PT There was a significant correlation between EN deletion and trastuzumab targeting Her2 positive breast cancer patients (p=0.006).PTEN deletion and trastul monoclonal antibody targeting treatment of Her2 positive breast cancer patients without significant correlation (p=0.460). (p=0.460) in the four types of molecular typing of breast cancer, Luminal A patients (6%), Luminal B patients 4 Cases (8%), 23 cases (46%) of Her2 positive patients and 20 cases (40%) of three negative patients, of which lymph node enlargement was 92.6%, lymph node metastases were 51.9%, and most of the patients were classified as invasive ductal carcinoma. (4) there was no significant correlation between the molecular classification of breast cancer and the expression of Bcl2, P53, MMP9, and PI3K 110 alpha. (5) PTEN eggs in breast cancer samples There was no significant correlation between 70%.PTEN expression and tumor diameter, lymph node enlargement and lymph node metastasis. The expression of.PTEN was significantly correlated with the expression of ER, Ki67 and MMP9 (P0.05), but there was no significant correlation between the expression of PTEN and the expression of PR, the expression of Her2, the expression of Bcl2, the P53 expression, and the expression of PI3K110 alpha. P0.05. 6 Cas9 plasmid construction of PTEN knockout breast cancer cell lines found that the expression of p-AKTThr308 and p-AKT Ser473 increased in the PI3K/Akt/mTOR pathway, and the expression of p-mTOR Ser2481 and p-mTOR Ser2448 increased. PTEN low expression or PTEN deletion had no difference in the prognosis of breast cancer patients, but meta data analysis showed that PTEN deletion indicated poor prognosis in Her2 positive breast cancer targeting Her2 targeted therapy. The immunohistochemical results showed that the expression of MMP9 in 70%. breast cancer tissues was up to 72%. in breast cancer tissues as high as 72%.. The MMP9 positive rate of migratory markers in PTEN missing samples was significantly higher than that of the normal PTEN samples. The expression of PTEN protein was significantly correlated with the expression of MMP9 (p=0.028). The deletion of PTEN was closely related to the high expression of MMP9. The ratio and number of lymph node metastases in patients with PTEN deletion were significantly higher than those of normal PTEN samples. PTEN is closely related to tumor migration and invasion in breast cancer. PTEN may be one of the markers for breast cancer invasion and metastasis. In the PTEN knockout breast cancer cell lines, the PTEN deletion or low expression activation plays a role in the activation of the PI3K/Akt/mTOR signaling pathway and has no significant influence on the Raf /MEK/ERK signaling pathway. Therefore PTEN Deletion may play a key role in the development and prognosis of breast cancer.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R737.9

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