miR-183-96-182簇及miR-135a调控乳腺癌恶性进展研究

发布时间：2018-07-12 14:59

本文选题：乳腺癌 + 生长激素　；参考：《中国科学技术大学》2015年博士论文

【摘要】：第一部分：人生长激素不仅在乳腺发育过程发挥重要作用,也有证据显示自分泌的人生长激素促进乳腺上皮细胞的恶性转化。之前我们报道生长激素通过促进乳腺细胞上皮间充质转变(EMT)增强细胞的侵袭能力,但具体机制并未详细探讨。这里,利用芯片技术,我们发现在乳腺癌细胞MCF7中自分泌的人生长激素调节一系列的微小RNA(miRNA)的表达水平。其中,受生长激素上调的miR-183-96-182簇介导了生长激素促进乳腺细胞上皮间充质转变的过程。在体外和体内实验中,过表达miR-183-96-182簇显著增强上皮样的MCF-7 细胞的迁移能力,同时伴随有细胞骨架的重排以及EMT相关蛋白表达水平的改变。进一步的研究证实miR-183-96-182簇是通过乳腺癌转移抑制蛋白1相似蛋白基因(BRMS1L)调节细胞的EMT过程。同时,生长激素受体(GHR)受到 miR-96和miR-182的直接调节,证实了生长激素-miR-183-96-182簇之间的负反馈调节机制。而且我们还发现受生长激素激活的信号转导及转录激活因子 STAT3和STAT5转录因子可以结合到miR-96-183-183簇启动子区激活 miR-183-96-182的转录。miR-183-96-182簇与BRMS1L的表达水平在乳腺癌病人样本中与淋巴结转移指标相关。研究揭示了人生长激素通过miR-183-96-182 簇调节乳腺癌转移的具体分子机制。第二部分：肿瘤组织的基因组研究可以为个体化的医疗方案以及治疗反应提供丰富的参考信息,但对特定基因组突变背后的机制研究是整合基因组信息和临床决策的关键。这里,我们报道人类三号染色体断臂上的MIR135A1基因在30%左右的乳腺癌病人中均存在拷贝丢失的现象,并且该类乳腺癌病人的预后相比其他病人明显较差。同时,MIR135A1基因的成熟产物,.miR-135a的表达水平也被发现在乳腺癌肿瘤组织中明显较良性组织低。在体内和体外实验中, 我们都证实了低的miR-135a表达水平与细胞的高恶性度以及转移潜力密切相关。在肿瘤组织中,miR-135a的水平与雌激素受体alpha(ERa)呈明显的正相关。进一步的研究证实MIR135A1基因的启动子区存在ERa响应元件(ERE), 在雌激素刺激下可以转录出更高水平的miR-135a。实验中还发现较低的 miR-135a水平可以削弱ERa阳性的细胞生长过程中对雌激素的依赖。在体外长期对细胞使用抗雌激素治疗药物他莫昔芬(tamoxifen)引起miR-135a不可逆的下调。在体内体外实验中我们都证实了miR-135a的下调是获得他莫昔芬抗性的充分必要条件。对miR-135a的下游信号通路的研究显示,miR-135a不仅可以通过靶点ERa(ESR1),雌激素受体alpha相关蛋白A(ESRRA)和核受体辅激活蛋白1(NCOA1)负反馈调节雌激素信号通路,而且抑制ERK和AKT信号通路上游基因PIM2, MRASLCP1的表达。这些研究揭示了miR-135a与乳腺癌发生发展中扮演重要角色的信号网络ERa-ERK-AKT之间的平衡机制,而MIR135A1基因的缺失或者长期的抗雌激素治疗破坏了该平衡从而导致乳腺癌的发展以及对他莫昔芬治疗的抗性产生。
[Abstract]:Part I : Human growth hormone plays an important role not only in the development of mammary gland , but also in evidence .

Self - secreted human growth hormone promotes malignant transformation of mammary epithelial cells . We report growth hormone .

Overpromoting mesenchymal transition ( EMT ) in the mammary gland cells enhances the invasion ability of cells , but specific mechanisms and

Not discussed in detail . Here , using chip technology , we have found that self - secreted in breast cancer cell MCF7

Human growth hormone regulates the level of expression of a series of miRNA .

Up - regulated miR - 183 - 96 - 182 cluster mediated growth hormone to promote mesenchymal transition of mammary gland cells

Cheng . Over - expression of miR - 183 - 96 - 182 clusters in vitro and in vivo experiments significantly enhanced epithelial - like MCF - 7

The migration ability of the cells is accompanied by the rearrangement of the cytoskeletal framework and the alteration of the expression level of EMT - related protein .

Further studies confirm that miR - 183 - 96 - 182 clusters are similar to those obtained by breast cancer metastasis suppressor protein 1

White gene ( BRMS1L ) regulates EMT process of cells . At the same time , the growth hormone receptor ( GHR ) is affected

Direct modulation of miR - 96 and miR - 182 confirms the negative between growth hormone - miR - 183 - 96 - 182 clusters

Feedback regulatory mechanisms . And we also found signal transduction and transcriptional activation factors activated by growth hormone

STAT5 Transcription Factor binds to the miR - 96 - 183 - 183 cluster promoter region activation

Transcription of miR - 183 - 96 - 182 . Expression level of miR - 183 - 96 - 182 cluster and BRMS1L in breast cancer

The study revealed that human growth hormone was passed through miR - 183 - 96 - 182 .

Cluster regulates the specific molecular mechanism of breast cancer metastasis . Part 2 : The gene group of tumor tissue can be a personalized medical regimen and therapeutic response .

Provides rich reference information , but the mechanism behind a particular genome mutation is to integrate genome information

and the key to clinical decision - making . Here , we report the gene of the human chromosome 3 on the genome of the gene .

There is a loss of copy in breast cancer patients around 30 % , and the pre - treatment of this type of breast cancer patient

At the same time , the mature product of the mir135A1 gene , the expression of miR -

the level was also found to be significantly lower in breast cancer tumor tissues than in benign tissues , in vivo and in vitro experiments ,

We all confirmed that the low expression level of miR - 135 was closely related to the high malignancy of the cell and the metastatic potential .

In the tumor tissues , the level of miR - A is positively correlated with the estrogen receptor alpha ( ERa ) .

Further studies confirm the presence of an ERa response element ( ERE ) in the promoter region of the mir135A1 gene ,

Higher levels of miR - 135 can be transcribed under estrogen stimulation . The experiments also find low

The level of miR - 135 can weaken the dependence of ERa - positive cells on estrogen during growth , and is long in vitro

The use of an anti - estrogen therapy drug tamoxifen for the cells in the period of time causes an irreversible miR -

Down - regulation . In in vitro experiments in vivo , we all confirmed that the down regulation of miR - 135 was tamoxifen resistant .

It is sufficient and necessary . Research on the downstream signaling pathway of miR -

Estrogen receptor alpha - associated protein A ( ESRRA ) and nuclear receptor sub - activator protein 1 ( NCOA1 ) negative feedback regulate estrogen signaling pathway through target ERa ( ESR1 ) , estrogen receptor alpha - associated protein A ( ESRRA ) , and nuclear receptor secondary activator protein 1 ( NCOA1 ) . These studies revealed a balance mechanism between ERK and ERa - ERK - 1 , a signaling network that plays an important role in the development of breast cancer , and the absence or long - term anti - estrogen treatment of either the mir135A1 gene disrupted the balance leading to the development of breast cancer and the resistance to tamoxifen therapy .
【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R737.9

【共引文献】