拉帕替尼逆转ER-α36介导的他莫昔芬耐药的分子机制研究
发布时间：2018-10-30 18:08
【摘要】：目的：已有研究发现ER-a36可通过非经典的雌激素膜信号传导通路,使激素受体阳性的乳腺癌对内分泌治疗产生耐药。拉帕替尼(Lapatinib)是一种小分子表皮生长因子酪氨酸激酶抑制剂,可通过阻断下调信号抑制乳腺癌细胞增殖。本研究将探索拉帕替尼是否能通过下调ER-a36相关非经典的雌激素膜信号传导通路,逆转激素受体阳性乳腺癌细胞的他莫昔芬(tamoxifen, TAM)耐药,并初步探索其逆转耐药的分子机制,为乳腺癌内分泌治疗及靶向治疗提供新的理论支持。 方法：运用MTT、AnnexinV-FITC/PI双染法流式细胞术、Western Blot等技术检测经拉帕替尼单药或加用4-羟基他莫昔芬(4-hydroxy-tamoxifen,4OHT)处理后乳腺癌细胞株的增殖情况及相关蛋白水平的变化。 结果：1、MTT检测可发现拉帕替尼对ER阳性乳腺癌细胞存在明显抑制作用,在MCF-7、MCF-7/ER-a36两细胞系中,存在剂量依赖效应；2、AnnexinV-FITC/PI双染法流式细胞仪检测发现拉帕替尼可显著增强40HT诱导激素受体阳性、ER-a36过表达的乳腺癌细胞凋亡(P0.001)；3、拉帕替尼预处理或与40HT联合作用均可加强凋亡起始、执行阶段关键Caspase家族蛋白剪切活化、抑制抗凋亡Bcl-2蛋白表达,下调细胞周期正性调控蛋白Cyclin D1、Cyclin D3、CDK2、CDK4等的表达；4、拉帕替尼显著抑制ER-a36相关非经典的雌激素膜信号传导通路中AktT308位点及S6K1蛋白的磷酸化活化,发挥增敏、部分逆转MCF-7/ER-a36对40HT耐药的作用。 结论：拉帕替尼可逆转ER阳性、ER-a36过表达的乳腺癌细胞对他莫昔芬的耐药,其主要通过(1)诱导细胞周期停滞与凋亡,(2)抑制ER-a36相关的非经典的Akt-mTOR信号传导通路过度活化,发挥逆转他莫昔芬耐药作用。拉帕替尼可能成为激素受体阳性、ER-a36过表达的他莫昔芬耐药乳腺癌治疗的新靶点。
[Abstract]:Aim: it has been found that ER-a36 can make hormone receptor-positive breast cancer resistant to endocrine therapy through non-classical estrogen membrane signaling pathway. Rapatini (Lapatinib) is a small molecular inhibitor of epidermal growth factor tyrosine kinase, which inhibits breast cancer cell proliferation by blocking down-regulation signals. This study will explore whether Rapatinib can reverse tamoxifen (tamoxifen, TAM) resistance in steroid-receptor-positive breast cancer cells by down-regulating the non-classical estrogen membrane signaling pathway associated with ER-a36. The molecular mechanism of reversal of drug resistance was preliminarily explored to provide new theoretical support for endocrine therapy and targeted therapy of breast cancer. Methods: MTT,AnnexinV-FITC/PI double staining flow cytometry (, Western Blot) and other techniques were used to detect 4-hydroxy-tamoxifenin (4-hydroxy-tamoxifen). After 4OHT treatment, the proliferation of breast cancer cell lines and the changes of related protein levels were observed. Results: (1) ER positive breast cancer cells were significantly inhibited by Rapatinib, and there was a dose-dependent effect in two MCF-7,MCF-7/ER-a36 cell lines. 2Annexin V-FITC / Pi double staining flow cytometry showed that Rapatinib could significantly enhance the apoptosis of breast cancer cells induced by 40HT and overexpression of ER-a36 (P0.001). 3, pretreatment with Rapatinib or combined with 40HT can enhance the initiation of apoptosis, shear activation of key Caspase family proteins, inhibit the expression of anti-apoptotic Bcl-2 protein, and down-regulate the cell cycle positive regulatory protein Cyclin D1 cyclin D3 CDK2. The expression of CDK4 et al. 4. Rapatini significantly inhibited the phosphorylation of AktT308 site and S6K1 protein in the non-classical estrogen membrane signal transduction pathway associated with ER-a36, and partially reversed the effect of MCF-7/ER-a36 on 40HT resistance. Conclusion: Rapatinib can reverse the drug resistance of breast cancer cells with ER positive and ER-a36 overexpression to tamoxifen mainly through (1) inducing cell cycle arrest and apoptosis. (2) inhibiting the overexpression of non-classical Akt-mTOR signal transduction pathway associated with ER-a36 and reversing tamoxifen resistance. Rapatinib may be a new target for tamoxifen-resistant breast cancer with hormone receptor positive and ER-a36 overexpression.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R737.9
本文编号：2300770
[Abstract]:Aim: it has been found that ER-a36 can make hormone receptor-positive breast cancer resistant to endocrine therapy through non-classical estrogen membrane signaling pathway. Rapatini (Lapatinib) is a small molecular inhibitor of epidermal growth factor tyrosine kinase, which inhibits breast cancer cell proliferation by blocking down-regulation signals. This study will explore whether Rapatinib can reverse tamoxifen (tamoxifen, TAM) resistance in steroid-receptor-positive breast cancer cells by down-regulating the non-classical estrogen membrane signaling pathway associated with ER-a36. The molecular mechanism of reversal of drug resistance was preliminarily explored to provide new theoretical support for endocrine therapy and targeted therapy of breast cancer. Methods: MTT,AnnexinV-FITC/PI double staining flow cytometry (, Western Blot) and other techniques were used to detect 4-hydroxy-tamoxifenin (4-hydroxy-tamoxifen). After 4OHT treatment, the proliferation of breast cancer cell lines and the changes of related protein levels were observed. Results: (1) ER positive breast cancer cells were significantly inhibited by Rapatinib, and there was a dose-dependent effect in two MCF-7,MCF-7/ER-a36 cell lines. 2Annexin V-FITC / Pi double staining flow cytometry showed that Rapatinib could significantly enhance the apoptosis of breast cancer cells induced by 40HT and overexpression of ER-a36 (P0.001). 3, pretreatment with Rapatinib or combined with 40HT can enhance the initiation of apoptosis, shear activation of key Caspase family proteins, inhibit the expression of anti-apoptotic Bcl-2 protein, and down-regulate the cell cycle positive regulatory protein Cyclin D1 cyclin D3 CDK2. The expression of CDK4 et al. 4. Rapatini significantly inhibited the phosphorylation of AktT308 site and S6K1 protein in the non-classical estrogen membrane signal transduction pathway associated with ER-a36, and partially reversed the effect of MCF-7/ER-a36 on 40HT resistance. Conclusion: Rapatinib can reverse the drug resistance of breast cancer cells with ER positive and ER-a36 overexpression to tamoxifen mainly through (1) inducing cell cycle arrest and apoptosis. (2) inhibiting the overexpression of non-classical Akt-mTOR signal transduction pathway associated with ER-a36 and reversing tamoxifen resistance. Rapatinib may be a new target for tamoxifen-resistant breast cancer with hormone receptor positive and ER-a36 overexpression.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R737.9
【参考文献】
相关期刊论文 前2条
1 何倩;潘跃银;;乳腺癌内分泌治疗的耐药机制及对策[J];临床肿瘤学杂志;2011年05期
2 李东阳;王白石;崔桂花;罗速;;ER-α36基因沉默对ER阴性乳腺癌MDA-MB-231细胞的作用及其影响[J];吉林医药学院学报;2014年03期
，本文编号：2300770
本文链接：https://www.wllwen.com/yixuelunwen/waikelunwen/2300770.html
最近更新
教材专著
