他莫昔芬(tamoxifen,TAM)作为雌激素受体阳性(estrogen receptor,ER+)乳腺癌的一线化疗药物使大多数患者受益,但原发性和继发性耐药问题严重影响临床治疗效果。深入研究ER+乳腺癌TAM耐药机制,改善治疗效果是当前亟待解决的问题。抑癌因...他莫昔芬(tamoxifen,TAM)作为雌激素受体阳性(estrogen receptor,ER+)乳腺癌的一线化疗药物使大多数患者受益,但原发性和继发性耐药问题严重影响临床治疗效果。深入研究ER+乳腺癌TAM耐药机制,改善治疗效果是当前亟待解决的问题。抑癌因子NDRG2(N-myc downstream regulated gene 2,NDRG2)在肿瘤发生发展中发挥重要作用,但是否参与ER+乳腺癌TAM耐药尚不清楚。本研究旨在探明NDRG2在ER+乳腺癌TAM耐药中发挥的作用和机制。通过RT-PCR与免疫印迹分析对比TAM敏感型和耐药型ER+乳腺癌细胞发现,NDRG 2的mRNA转录水平和蛋白质翻译水平在TAM耐药细胞中表达显著下调,且与耐药能力负相关(P<0.001);CCK-8细胞毒性实验和软琼脂克隆形成实验证实,在耐药细胞中过表达NDRG2可显著降低TAM药物半抑制浓度IC 50和软琼脂克隆形成率(P<0.001),逆转耐药表型。分子机制上,X-box结合蛋白1(X-box binding protein 1,XBP1)mRNA剪切实验与内质网相关降解(endoplasmic-reticulum associated degradation,ERAD)报告蛋白的结果显示,过表达NDRG2可增强耐药细胞中剪切型XBP1s mRNA转录与ERAD报告蛋白CD3ε-YFP表达(P<0.001),引发耐药细胞内质网强应激反应;免疫印迹检测结果显示,过表达NDRG2可显著提高耐药细胞中内质网应激感受器肌醇需要激酶1α(inositol requiring enzyme 1,IRE1α)的磷酸化水平及其下游因子,例如内质网EIP辅助因子(endoplasmic reticulum-localized DnaJ 4,ERdj4)、PKR蛋白激酶的细胞抑制剂(cellular Inhibitor of the PKR protein kinase,P58 IPK)、α甘露糖苷酶样应激蛋白(er degradation enhancingαmannosidase likeprotein,EDEM)和蛋白质二硫键异构酶家族A成员5(protein disulfide isomerase family a member 5,PDIA5)的表达水平(P<0.001)。小鼠异种移植瘤研究进一步证实,在耐药细胞中过表达NDRG2可增强TAM治疗效果,显著抑制耐药移植瘤生长(P<0.001)。以上研究结果表明,通过提高耐药细胞中NDRG2表达,增强TAM治疗引发的内质网强烈应激,可逆转ER+乳腺癌细胞耐药性,改善TAM治疗效果。研究结果为解决ER+乳腺癌TAM耐药问题提供了新的思路和有价值的潜在药物靶点。展开更多
Aim Breast cancer is one of the lethal gynecological malignancy in the world. Tamoxifen （TAM） and fulvestrant （FUL） are the major drugs for patients with estrogen receptor-positive （ER ＋ ） breast cancers. Howev...Aim Breast cancer is one of the lethal gynecological malignancy in the world. Tamoxifen （TAM） and fulvestrant （FUL） are the major drugs for patients with estrogen receptor-positive （ER ＋ ） breast cancers. Howev- er, the development of endocrine resistance is the impediment for successful treatment. In this study, we explored the mechanisms of endocrine resistance and therapeutic strategy for overcoming resistance against TAM and FUL. Methods The experiments were performed in Ell ＋ and estrogen/TAM-sensitive MCF7 cells and antiestrogen-re- sistant MCF7/LCC9 cells. Western blot and confocal microscopy were used to determine cell autophagy. Cell trans- fection and luciferase activity assay were performed to identify the target gene of miR-214. Results It showed that 4-OHT/FUL treatment induced apoptosis as well as autophagy in breast cancer cells. The increase of autophagy might be the major cause of endocrine resistance to 4-OHT or FUL. Mill-214 increased the sensitivity of breast cancer cells to the 4-OHT/FUL-induced apoptosis through inhibition of autophagy. Importantly, a negative correla- tion was established between miR-214 and UCP2 in human breast cancer tissue specimens by RT-qPCR assay. UCP2 was identified to be a direct target of mill-214. Further study in MCF7/LCC9 cells indicated that endocrine resistance might arise from activation of the PI3 K-Akt-mTOll pathway, thereby inducing autophagy by overexpres- sion of UCP2. Conclusions MiR-214 increased the sensitivity of breast cancer cells to TAM and FUL through in- hibition of autophagy by targeting UCP2. Mill-214 shows potential as a novel therapeutic strategy for overcoming endocrine resistance in ER ＋ breast cancers.展开更多
Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell ...Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell cycle distribution and apoptosis induction were analyzed by using flow cytometry when breast cancer cell lines MCF-7 were cotreated with daidzein （1, 5 μmol/L） and E2 （0.1-10 nmol/L） for 5 days. Whether daidzein could alter E2-modulated mRNA expression of estrogen receptor alpha （ERα）, estrogen receptor beta （ERI3） and ERβ-estrogen response element （ERE） dependent transcription was investigated by RT-PCR and luciferase induction assays. The effects of daidzein on E2-modulated expression of proapoptotic p53, bax and antiapoptotic bcl-2 at both mRNA and protein levels were also investigated by RT-PCR and Western blot. Results： Daidzein enhanced the antiapoptotic effect in an Ea dose-dependent manner, but had no effect on E2-induced proliferation. Daidzein antagonized E2-induced ERβ mRNA expression and ERβ-ERE dependent transcription. In addition, daidzein only antagonized E2-upregulated expression of p53 and bax, but had no effect on E2-upregulated expression of bcl-2. Conclusion： Daidzein enhances the antiapoptotic effect of E2 on breast cancer cells by inhibiting E2-mediated p53-bax proapoptotic pathway. These results suggest that dietary daidzein may enhance deleterious effect of endogenous E2 in hormone-dependent breast cancer.展开更多
Aim Recent evidence has revealed that Eukaryotic elongation factor-2 kinase （eEF2K） activity may confer cancer cell adaptation to metabolic stress, and high expression of eEF2K is found in several types of cancer. T...Aim Recent evidence has revealed that Eukaryotic elongation factor-2 kinase （eEF2K） activity may confer cancer cell adaptation to metabolic stress, and high expression of eEF2K is found in several types of cancer. Therefore, eEF2K may contribute to carcinogenesis and represent a promising therapeutic target; however, inhibi- tion of eEF2K for cancer drug discovery still remains in its infancy. This study aimed at developing a series of eEF2K inhibitor as candidate anti-tumor drugs in breast cancer and illustrating the possible mechanisms of its anti- tumor activity in vitro and in vivo. Methods In silico screening, structure modifications, MTT assay and molecular dynamics （MD） simulations were applied for the discovery of the novel eEF2K inhibitor （BL-EKI03）. Observa- tions of cell morphology were executed through several methods including ER-traeker, MDC and Hoeehst 33258 staining and GFP-LC3 transfeetion. Flow eytometrie analyses of MDC and Annexin V/PI were used for quantifica- tion of autophagy and apoptosis ratio. Western blot and ITRAQ analysis were used to explore the detailed mecha- nisms of BL-EKI03-induced ER stress, autophagie death and apoptosis in breast cancer cells. Furthermore, an in vivo xenograft mouse model was established for validating the anti-tumor efficacy of BL-EKI03. Results Firstly, a novel eEF2K inhibitor （BL-EKI03） with a good affinity for eEF2K was eventually discovered after computational screening and synthesis of a series of candidate compounds targeting eEF2K. Subsequently, our results demonstra- ted that BL-EKI03 has remarkable anti-proliferative activities and induces endoplasmie retieulum （ER） stress, au- tophagy and apoptosis in MCF-7 and MDA-MB-436 cells. More importantly, the mechanism for BL-EKI03-indueed autophagie death involves eEF2K-mediated AMPK-mTOR-ULK complex pathways. The proteomies analyses and ex-perimental validation revealed that the BL-EKI03-induced mechanism was also involved BIRC6, BNIP1, SNAP29 and Bif-1, which might be regulated by eEF2K. Moreover, BL-EKI03 exerted its anti-tumor activities without re- markable toxicity, and it also induced autophagy and apoptosis by targeting eEF2K in fifo. Conclusion In this study, a novel eEF2K inhibitor （BL-EKI03） was discovered with remarkable anti-proliferative activities and in- duced endoplasmic reticulum （ER） stress, autophagy and apoptosis of breast cancer in vitro and in fifo. These findings highlight a new small-molecule eEF2K inhibitor （BL-EKI03） that has the potential to impact future breast cancer therapy.展开更多
About 30% of human breast cancers are human epidermal growth factor receptor 2 （HER2）＋. This particular biological portrait is characterized by the overexpression of HER2 receptor with the subsequent deregulation o...About 30% of human breast cancers are human epidermal growth factor receptor 2 （HER2）＋. This particular biological portrait is characterized by the overexpression of HER2 receptor with the subsequent deregulation of downstream pathways, which control cellular survival and proliferation. The most effective treatment for HER2＋ cancer is represented by therapy with HER2-targeted agents. Anti-HER2 therapy dramatically improves clini-cal outcomes, although it shows some limitations in achieving a proper treatment. These drawbacks of HER2-targeted therapy may be overcome with the develop-ment of HER2-targeted drug delivery nanodevices. These nanoparticles possess an internal three-dimensional com-partimentalization, which allows to combine the specifc target recognition with their capability to act as a drug reservoir for the selective delivery of chemotherapics to tumor sites. Moreover, nanoparticles useful in photo-thermal ablation or in photodynamic therapy have been functionalized in order to match specifcity in tumor cell recognition and suitable chemical properties. Here, we summarize the state of the art concerning the HER2＋ breast cancer and anti-HER2 therapy, in particular deep-ening the contribution of the nanomedicine. Description of preclinical studies performed with HER2-targeted nanoparticles for HER2＋ breast cancer therapy will be preceded by an overview on HER2-targeting molecules and nano-conjugation strategies. Further investigation will be necessary to introduce these nano-drugs in clinical prac-tice; however promising results encourage an upcoming translation of this research for the next future.展开更多
Objective: The purpose of the study was to investigate the relationship between the expression of estrogen receptor(ER), progestogen receptor(PR), human epidermal growth factor receptor(Her-2), Ki-67 and the effect of...Objective: The purpose of the study was to investigate the relationship between the expression of estrogen receptor(ER), progestogen receptor(PR), human epidermal growth factor receptor(Her-2), Ki-67 and the effect of neoadjuvant chemotherapy in breast cancer. Methods: The expression of ER, PR, Her-2 and Ki-67 in 45 breast cancers which received neoadjuvant chemotherapy was detected by immunohistochemistry. Results: The effective rates in ER negative and PR negative groups were higher than those in ER positive and PR positive groups(83.3% vs 59. 4%, 82.4% vs 60.6%). There was no significant difference of the effective rate between Her-2 overexpressed group and Her-2 non-overexpressed group(81.8% vs 64.1%), and the same thing happened between Ki-67 negative group and Ki-67 positive group(67.7% vs 63.2%). Conclusion: In the patients with breast cancer, ER, PR negative ones were more sensitive to neoadjuvant chemotherapy. These patients may get more benefits from chemotherapy. ER, PR could be feasible markers for predicting the effective rate of neoadjuvant chemotherapy.展开更多
文摘他莫昔芬(tamoxifen,TAM)作为雌激素受体阳性(estrogen receptor,ER+)乳腺癌的一线化疗药物使大多数患者受益,但原发性和继发性耐药问题严重影响临床治疗效果。深入研究ER+乳腺癌TAM耐药机制,改善治疗效果是当前亟待解决的问题。抑癌因子NDRG2(N-myc downstream regulated gene 2,NDRG2)在肿瘤发生发展中发挥重要作用,但是否参与ER+乳腺癌TAM耐药尚不清楚。本研究旨在探明NDRG2在ER+乳腺癌TAM耐药中发挥的作用和机制。通过RT-PCR与免疫印迹分析对比TAM敏感型和耐药型ER+乳腺癌细胞发现,NDRG 2的mRNA转录水平和蛋白质翻译水平在TAM耐药细胞中表达显著下调,且与耐药能力负相关(P<0.001);CCK-8细胞毒性实验和软琼脂克隆形成实验证实,在耐药细胞中过表达NDRG2可显著降低TAM药物半抑制浓度IC 50和软琼脂克隆形成率(P<0.001),逆转耐药表型。分子机制上,X-box结合蛋白1(X-box binding protein 1,XBP1)mRNA剪切实验与内质网相关降解(endoplasmic-reticulum associated degradation,ERAD)报告蛋白的结果显示,过表达NDRG2可增强耐药细胞中剪切型XBP1s mRNA转录与ERAD报告蛋白CD3ε-YFP表达(P<0.001),引发耐药细胞内质网强应激反应;免疫印迹检测结果显示,过表达NDRG2可显著提高耐药细胞中内质网应激感受器肌醇需要激酶1α(inositol requiring enzyme 1,IRE1α)的磷酸化水平及其下游因子,例如内质网EIP辅助因子(endoplasmic reticulum-localized DnaJ 4,ERdj4)、PKR蛋白激酶的细胞抑制剂(cellular Inhibitor of the PKR protein kinase,P58 IPK)、α甘露糖苷酶样应激蛋白(er degradation enhancingαmannosidase likeprotein,EDEM)和蛋白质二硫键异构酶家族A成员5(protein disulfide isomerase family a member 5,PDIA5)的表达水平(P<0.001)。小鼠异种移植瘤研究进一步证实,在耐药细胞中过表达NDRG2可增强TAM治疗效果,显著抑制耐药移植瘤生长(P<0.001)。以上研究结果表明,通过提高耐药细胞中NDRG2表达,增强TAM治疗引发的内质网强烈应激,可逆转ER+乳腺癌细胞耐药性,改善TAM治疗效果。研究结果为解决ER+乳腺癌TAM耐药问题提供了新的思路和有价值的潜在药物靶点。
文摘Aim Breast cancer is one of the lethal gynecological malignancy in the world. Tamoxifen （TAM） and fulvestrant （FUL） are the major drugs for patients with estrogen receptor-positive （ER ＋ ） breast cancers. Howev- er, the development of endocrine resistance is the impediment for successful treatment. In this study, we explored the mechanisms of endocrine resistance and therapeutic strategy for overcoming resistance against TAM and FUL. Methods The experiments were performed in Ell ＋ and estrogen/TAM-sensitive MCF7 cells and antiestrogen-re- sistant MCF7/LCC9 cells. Western blot and confocal microscopy were used to determine cell autophagy. Cell trans- fection and luciferase activity assay were performed to identify the target gene of miR-214. Results It showed that 4-OHT/FUL treatment induced apoptosis as well as autophagy in breast cancer cells. The increase of autophagy might be the major cause of endocrine resistance to 4-OHT or FUL. Mill-214 increased the sensitivity of breast cancer cells to the 4-OHT/FUL-induced apoptosis through inhibition of autophagy. Importantly, a negative correla- tion was established between miR-214 and UCP2 in human breast cancer tissue specimens by RT-qPCR assay. UCP2 was identified to be a direct target of mill-214. Further study in MCF7/LCC9 cells indicated that endocrine resistance might arise from activation of the PI3 K-Akt-mTOll pathway, thereby inducing autophagy by overexpres- sion of UCP2. Conclusions MiR-214 increased the sensitivity of breast cancer cells to TAM and FUL through in- hibition of autophagy by targeting UCP2. Mill-214 shows potential as a novel therapeutic strategy for overcoming endocrine resistance in ER ＋ breast cancers.
基金supported by the National Natural Science Foundation of China (No.30671508)by State Key Laboratory for Agrobiotechnology of China (No.2009SKLAB07-5)
文摘Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell cycle distribution and apoptosis induction were analyzed by using flow cytometry when breast cancer cell lines MCF-7 were cotreated with daidzein （1, 5 μmol/L） and E2 （0.1-10 nmol/L） for 5 days. Whether daidzein could alter E2-modulated mRNA expression of estrogen receptor alpha （ERα）, estrogen receptor beta （ERI3） and ERβ-estrogen response element （ERE） dependent transcription was investigated by RT-PCR and luciferase induction assays. The effects of daidzein on E2-modulated expression of proapoptotic p53, bax and antiapoptotic bcl-2 at both mRNA and protein levels were also investigated by RT-PCR and Western blot. Results： Daidzein enhanced the antiapoptotic effect in an Ea dose-dependent manner, but had no effect on E2-induced proliferation. Daidzein antagonized E2-induced ERβ mRNA expression and ERβ-ERE dependent transcription. In addition, daidzein only antagonized E2-upregulated expression of p53 and bax, but had no effect on E2-upregulated expression of bcl-2. Conclusion： Daidzein enhances the antiapoptotic effect of E2 on breast cancer cells by inhibiting E2-mediated p53-bax proapoptotic pathway. These results suggest that dietary daidzein may enhance deleterious effect of endogenous E2 in hormone-dependent breast cancer.
文摘Aim Recent evidence has revealed that Eukaryotic elongation factor-2 kinase （eEF2K） activity may confer cancer cell adaptation to metabolic stress, and high expression of eEF2K is found in several types of cancer. Therefore, eEF2K may contribute to carcinogenesis and represent a promising therapeutic target; however, inhibi- tion of eEF2K for cancer drug discovery still remains in its infancy. This study aimed at developing a series of eEF2K inhibitor as candidate anti-tumor drugs in breast cancer and illustrating the possible mechanisms of its anti- tumor activity in vitro and in vivo. Methods In silico screening, structure modifications, MTT assay and molecular dynamics （MD） simulations were applied for the discovery of the novel eEF2K inhibitor （BL-EKI03）. Observa- tions of cell morphology were executed through several methods including ER-traeker, MDC and Hoeehst 33258 staining and GFP-LC3 transfeetion. Flow eytometrie analyses of MDC and Annexin V/PI were used for quantifica- tion of autophagy and apoptosis ratio. Western blot and ITRAQ analysis were used to explore the detailed mecha- nisms of BL-EKI03-induced ER stress, autophagie death and apoptosis in breast cancer cells. Furthermore, an in vivo xenograft mouse model was established for validating the anti-tumor efficacy of BL-EKI03. Results Firstly, a novel eEF2K inhibitor （BL-EKI03） with a good affinity for eEF2K was eventually discovered after computational screening and synthesis of a series of candidate compounds targeting eEF2K. Subsequently, our results demonstra- ted that BL-EKI03 has remarkable anti-proliferative activities and induces endoplasmie retieulum （ER） stress, au- tophagy and apoptosis in MCF-7 and MDA-MB-436 cells. More importantly, the mechanism for BL-EKI03-indueed autophagie death involves eEF2K-mediated AMPK-mTOR-ULK complex pathways. The proteomies analyses and ex-perimental validation revealed that the BL-EKI03-induced mechanism was also involved BIRC6, BNIP1, SNAP29 and Bif-1, which might be regulated by eEF2K. Moreover, BL-EKI03 exerted its anti-tumor activities without re- markable toxicity, and it also induced autophagy and apoptosis by targeting eEF2K in fifo. Conclusion In this study, a novel eEF2K inhibitor （BL-EKI03） was discovered with remarkable anti-proliferative activities and in- duced endoplasmic reticulum （ER） stress, autophagy and apoptosis of breast cancer in vitro and in fifo. These findings highlight a new small-molecule eEF2K inhibitor （BL-EKI03） that has the potential to impact future breast cancer therapy.
文摘About 30% of human breast cancers are human epidermal growth factor receptor 2 （HER2）＋. This particular biological portrait is characterized by the overexpression of HER2 receptor with the subsequent deregulation of downstream pathways, which control cellular survival and proliferation. The most effective treatment for HER2＋ cancer is represented by therapy with HER2-targeted agents. Anti-HER2 therapy dramatically improves clini-cal outcomes, although it shows some limitations in achieving a proper treatment. These drawbacks of HER2-targeted therapy may be overcome with the develop-ment of HER2-targeted drug delivery nanodevices. These nanoparticles possess an internal three-dimensional com-partimentalization, which allows to combine the specifc target recognition with their capability to act as a drug reservoir for the selective delivery of chemotherapics to tumor sites. Moreover, nanoparticles useful in photo-thermal ablation or in photodynamic therapy have been functionalized in order to match specifcity in tumor cell recognition and suitable chemical properties. Here, we summarize the state of the art concerning the HER2＋ breast cancer and anti-HER2 therapy, in particular deep-ening the contribution of the nanomedicine. Description of preclinical studies performed with HER2-targeted nanoparticles for HER2＋ breast cancer therapy will be preceded by an overview on HER2-targeting molecules and nano-conjugation strategies. Further investigation will be necessary to introduce these nano-drugs in clinical prac-tice; however promising results encourage an upcoming translation of this research for the next future.
文摘Objective: The purpose of the study was to investigate the relationship between the expression of estrogen receptor(ER), progestogen receptor(PR), human epidermal growth factor receptor(Her-2), Ki-67 and the effect of neoadjuvant chemotherapy in breast cancer. Methods: The expression of ER, PR, Her-2 and Ki-67 in 45 breast cancers which received neoadjuvant chemotherapy was detected by immunohistochemistry. Results: The effective rates in ER negative and PR negative groups were higher than those in ER positive and PR positive groups(83.3% vs 59. 4%, 82.4% vs 60.6%). There was no significant difference of the effective rate between Her-2 overexpressed group and Her-2 non-overexpressed group(81.8% vs 64.1%), and the same thing happened between Ki-67 negative group and Ki-67 positive group(67.7% vs 63.2%). Conclusion: In the patients with breast cancer, ER, PR negative ones were more sensitive to neoadjuvant chemotherapy. These patients may get more benefits from chemotherapy. ER, PR could be feasible markers for predicting the effective rate of neoadjuvant chemotherapy.
