雄激素受体在乳腺癌细胞中的表达及其对细胞增殖的影响

目的 检测雄激素受体(AR)在乳腺癌细胞中的表达,并观察雄激素刺激对乳腺癌细胞增殖的影响.方法 选择雌激素受体(ER)阳性的MCF-7和ER阴性的MDA-MB-453乳腺癌细胞,体外培养,Western blot技术检测两乳腺癌细胞株中AR蛋白的表达,MTT法检测用1×10-7、1×10-8和1×10-9 mol/L不同浓度的雄激素二氢睾酮(DHT)分别干预48、96、144 h后的细胞增殖,并应用流式细胞术检测DHT刺激乳腺癌细胞72 h后细胞周期的变化.结果 两个乳腺癌细胞株经DHT作用后AR蛋白表达均增多,DHT通过AR抑制MCF-7和MDA-MB-453两个乳腺癌细胞株的生长,各时间段不同浓度组比较A值差异无统计学意义(P＞0.05),细胞周期结果显示G1期细胞比例增高,S期细胞比例降低.结论 雄激素受体途径对ER阳性的MCF-7和ER阴性的MDA-MB-453乳腺癌细胞均有抑制生长作用,可能通过抑制细胞由G1期到S期转化来实现的.

Abstract：

Objective To evaluate the expression of androgen receptor (AR) in the breast cancer cell lines and its effect on proliferation of breast cancer cells. Methods The estrogen receptor (ER) -positive MCF-7 and ER-negative MDA-MB-453 cells were involved in this study and cultured in vitro. The expression of AR was detected by using Western blotting. Cell proliferation was determined by methyl thiazol tetrazolium (MTT) assay after the treatment with different concentrations of dihydrotestosterone (DHT) ( 1 x 10 -7, 1 x 10- 8, 1 x 10 -9 mol/L) for 48, 96 and 144 h respectively. Cell cycle was analyzed by flow cytometry following culture for 72 h. Results DHT increased the AR expression in the two breast cancer cell lines. AR pathway could inhibit proliferation of MCF-7 and MDA-MB-453 cells. There was no significant difference in absorbance values among three treatment groups at different time points (P ＞ 0. 05). Cell cycle analysis revealed that the proportion of cells at G1 phase was increased, and that at S phase decreased. Conclusion AR pathway may inhibit proliferation of ER-negative MDA-MB-453 breast cells as well as ER-positive MCF-7 cells, by suppressing the process of G1 to S phase progression.     

雄激素受体在乳腺癌细胞中的表达及其对细胞增殖的影响

Objective To evaluate the expression of androgen receptor (AR) in the breast cancer cell lines and its effect on proliferation of breast cancer cells. Methods The estrogen receptor (ER) -positive MCF-7 and ER-negative MDA-MB-453 cells were involved in this study and cultured in vitro. The expression of AR was detected by using Western blotting. Cell proliferation was determined by methyl thiazol tetrazolium (MTT) assay after the treatment with different concentrations of dihydrotestosterone (DHT) ( 1 x 10 -7, 1 x 10- 8, 1 x 10 -9 mol/L) for 48, 96 and 144 h respectively. Cell cycle was analyzed by flow cytometry following culture for 72 h. Results DHT increased the AR expression in the two breast cancer cell lines. AR pathway could inhibit proliferation of MCF-7 and MDA-MB-453 cells. There was no significant difference in absorbance values among three treatment groups at different time points (P ＞ 0. 05). Cell cycle analysis revealed that the proportion of cells at G1 phase was increased, and that at S phase decreased. Conclusion AR pathway may inhibit proliferation of ER-negative MDA-MB-453 breast cells as well as ER-positive MCF-7 cells, by suppressing the process of G1 to S phase progression.     

雄激素受体在乳腺癌细胞中的表达及其对细胞增殖的影响

Objective To evaluate the expression of androgen receptor (AR) in the breast cancer cell lines and its effect on proliferation of breast cancer cells. Methods The estrogen receptor (ER) -positive MCF-7 and ER-negative MDA-MB-453 cells were involved in this study and cultured in vitro. The expression of AR was detected by using Western blotting. Cell proliferation was determined by methyl thiazol tetrazolium (MTT) assay after the treatment with different concentrations of dihydrotestosterone (DHT) ( 1 x 10 -7, 1 x 10- 8, 1 x 10 -9 mol/L) for 48, 96 and 144 h respectively. Cell cycle was analyzed by flow cytometry following culture for 72 h. Results DHT increased the AR expression in the two breast cancer cell lines. AR pathway could inhibit proliferation of MCF-7 and MDA-MB-453 cells. There was no significant difference in absorbance values among three treatment groups at different time points (P ＞ 0. 05). Cell cycle analysis revealed that the proportion of cells at G1 phase was increased, and that at S phase decreased. Conclusion AR pathway may inhibit proliferation of ER-negative MDA-MB-453 breast cells as well as ER-positive MCF-7 cells, by suppressing the process of G1 to S phase progression.     

乳腺癌干细胞放疗反应性和耐受机制的研究

Objective To discuss the response of breast cancer stem cells to radiation and its resistant mechanism. Methods Single breast cancer stem cells were isolated from the human breast adenocarcinoma cell line, MCF-7, and suspension-cultured into mammary cell microspheres in vitro. The radiosensitivity of these breast cancer stem cells were evaluated using a colony formation assay. Real-time polymerase chain reaction (PCR) was used to detect the expression levels of the following genes before and after radiation in the breast cancer stem cells, along with non-stem cells of the breast cancer cell line: ATM, p53, Her-2, Ku70/Ku80 and Survivin. Results The average survival fraction (SF2) of the suspensioncultured MCF-7 cells after 2 Gy of radiation was 0. 49, while the average SF2 of MCF-7 cells cultured as a monolayer was 0. 27 (P<0.01). Compared to the MCF-7 cells grown in a monolayer, the suspension-cultured MCF-7 cells had higher expression levels of ATM, p53, Her-2, Ku70/Ku80 and Survivin; The expression of ATM, p53, Her-2, Ku70/Ku80 and Survivin was 5. 29±1. 36,1. 37±0. 73,2.10±0. 57,4. 69±1. 45,and 1. 80±1.29 fold, respectively. Conclusion Breast cancer stem cells have stronger anti-radiation capabilities than breast cancer non-stem cells. The stronger DNA repair capacity is an important resistant mechanism about radiotherapy of breast cancer stem cells.     

乳腺癌干细胞放疗反应性和耐受机制的研究

Objective To discuss the response of breast cancer stem cells to radiation and its resistant mechanism. Methods Single breast cancer stem cells were isolated from the human breast adenocarcinoma cell line, MCF-7, and suspension-cultured into mammary cell microspheres in vitro. The radiosensitivity of these breast cancer stem cells were evaluated using a colony formation assay. Real-time polymerase chain reaction (PCR) was used to detect the expression levels of the following genes before and after radiation in the breast cancer stem cells, along with non-stem cells of the breast cancer cell line: ATM, p53, Her-2, Ku70/Ku80 and Survivin. Results The average survival fraction (SF2) of the suspensioncultured MCF-7 cells after 2 Gy of radiation was 0. 49, while the average SF2 of MCF-7 cells cultured as a monolayer was 0. 27 (P<0.01). Compared to the MCF-7 cells grown in a monolayer, the suspension-cultured MCF-7 cells had higher expression levels of ATM, p53, Her-2, Ku70/Ku80 and Survivin; The expression of ATM, p53, Her-2, Ku70/Ku80 and Survivin was 5. 29±1. 36,1. 37±0. 73,2.10±0. 57,4. 69±1. 45,and 1. 80±1.29 fold, respectively. Conclusion Breast cancer stem cells have stronger anti-radiation capabilities than breast cancer non-stem cells. The stronger DNA repair capacity is an important resistant mechanism about radiotherapy of breast cancer stem cells.     

慢病毒介导CCL5-siRNA对乳腺癌细胞生物学行为的影响

Objective To study the effect of lentivirus-mediated CCL5-RNAi on the biological behaviors of human breast cancer cells. Methods CCL5-specific siRNA gene was synthesized and cloned into the recombinant lentiviral vector, pGCSIL-GFP. Human high-metastatic breast cancer cells, MDA-MB-231, were infected by CCL5-siRNA recombinant lentivirus, which was set as KD group. Cells infected with CCL5-NC was as NC group, and cells cultured was as CON group. The expression of CCL5 mRNA and protein in MDA-MB-231 cells was detected by RT-PCR and western blot, respectively. Cell growth suppression and cell cycle was observed by MTT assay and fluorescence activated cell sorting (FACS). Colony formation and migration ability were determined by colony-rorming assay and Boyden chamber method. Results After infection of CCL5-siRNA recombinant lentivirus, the expression level of CCL5 mRNA and protein in MDA-MB-231 cells as well as the colony formation and migration ability decreased significantly, but cell's proliferation was not affected obviously. Compared with MDA-MB-231 (0.88± 0.15) and MDA-MB-231/CCL5-NC (1.00±0.07) cells, the expression of CCL5 mRNA in MDA-MB-231/ CCL5-siRNA decreased to 0.18±0.03, P<0.01. Compared with MDA-MB-231/CCL5-NC (1.82±0.18) cells, the expression of CCL5 protein in MDA-MB-231/CCL5-siRNA decreased to 0.33±0.13, P <0.01. Colony-forming assay and Boyden chamber method showed that the colony formation and migration ability of MDA-MB-231/CCL5-siRNA decreased markedly (P<0.05). The clone count in KD group was (0.33± 0.10), which was a significant decrease from (0.97±0.09) (NC group) and (1.04±0.07) (CON group), P<0.05. The number of cells that migrated through the chamber membrane of KD group (38± 15) was less than that of NC group (77±11, P <0.05) and CON group (69±9, P <0.05). However, MTT assay and FACS revealed that the proliferation of MDA-MB-231/CCL5-siRNA was not different from MDA-MB-231/CCL5-NC and MDA-MB-231 (P>0.05), the proliferation index (PI) of group KD, NC and CON were (0.48±0.02), (0.44±0.05) and (0.47±0.02) respectively. The difference was not statistically significant by multiple comparison (P>0.05). Conclusion CCL5-specific siRNA can specifically suppress the colony formation and migration of human high-matastatic breast cancer cells.     

转染ERα基因对MDA-MB-231乳腺癌细胞白细胞介素-8表达的影响

目的 通过转染GFP-C1-ERα质粒建立稳定表达ERα的MDA-MB-23l细胞株,观察ERα对该细胞株白细胞介素(IL)-8表达的影响.方法 pEGFP-C1-ERα质粒经酶切和测序后转染MDA-MB-231细胞,使用G418筛选出稳定表达的克隆并鉴定.使用荧光逆转录-聚合酶链反应(RT-PCR)分别测定稳定转染ERα的MDA-MB-231细胞、MDA-MB-231细胞及MCF-7细胞的IL-8mRNA的表达,使用酶联免疫吸附试验(ELISA)法测定细胞上清液IL-8的浓度.结果 成功建立ERα阳性表达的MDA-MB-231细胞株,转染ERα的细胞株IL-8 mRNA的合成(105±16)ng/L明显低于MDA-MB-231细胞(195±32)ng/L(P<0.05),但仍然高于MCF-7细胞(32±4)ng/L(P<0.05),转染后细胞上清液IL-8浓度较未转染细胞明显降低,分别为(3499±312)ng/L和(6788±427)ng/L(P<0.05),但仍然高于MCF-7细胞(1846±44)ng/L(P<0.05).结论 稳定转染ERα基因抑制了MDA-MB-231细胞的IL-8的合成和分泌.     

人平衡型核苷载体在乳腺癌细胞中的表达情况及其对5-FU药效的影响

目的研究乳腺癌细胞株MDA-MB-231、MDA-MB-468、SK-BR-3、MCF-7中人平衡型核苷载体（hENTS）的表达及其对5氟尿嘧啶（5-Fu）细胞毒性的影响。方法MDA-MB-231、MDA—MB-468、SK-BR-3、MCF-7细胞常规培养于含10％小牛血清的高糖DMEM培养液中。逆转录．聚合酶链反应（RT-PCR）检测4种细胞株中hENTlmRNA及hENT2mRNA的表达。每种细胞分别在含有一定浓度序列（1．28×10^4ng／L～2．00×10^8ng／L）5-FU的培养液中培养48h。MTT法检测4种细胞株增殖,并计算其5-FU的半数抑制浓度（IC50）。结果①bENT1及hENT2mRNA在MDA-MB-231、MDA-MB-468、SK-BR-3细胞中的表达均较其在MCF-7细胞中（P伊〈0．05）,但其表达在MDA-MB-231、MDA-MB-468、SK-BR-3细胞中差异无统计学意义（P〉0．05）。hENT2mRNA表达在4种细胞中均较hENT1 mRNA表达低,差异有统计学意义（P〈0．05）。②MTT结果显示,5-FU的IC50在MDA-MB-231、MDA-MB-468、SK-BR-3细胞株中均较在MCF-7细胞株中低（P〈0．05）,在MDA-MB-231、MDA-MB-468、SK-BR-3细胞株之间差异无统计学意义（P〉0．05）。③在5-FU的IC50 较低的乳腺癌细胞株（MDA-MB-231、MDA—MB-468、SK-BR-3）中高表达hENTs,而在5-Fu的Ic50较高的乳腺癌细胞株（MCF-7）中,低表达hENTs或无表达。结论在乳腺癌细胞株中,细胞膜上hENTs的表达情况能显著影响5-FU的作用效果,其结果提示,在临床上可能需要依据hENTs的表达情况来选择核苷类抗癌药物。     

反义RNA抑制Ezrin表达对乳腺癌细胞侵袭能力的影响

目的 观察特异性阻断Ezrin的表达对人乳腺癌细胞MDA-MB-231和MCF-7的增殖和侵袭能力的影响.方法 将anti-pCR3.1-Ezrin质粒经脂质体介导,转染人人乳腺癌细胞MDA-MB-231 6、12和24 h,应用Western blot和逆转录-聚合酶链反应(RT-PCR)方法检测Ezrin的表达变化情况;转染质粒24h后,噻唑蓝(MTT)比色法检测抑制Ezrin对MDA-MB-231和MCF-7细胞体外增殖能力的影响,Boyden小室法检测抑制Ezrin对MDA-MB-231和MCF-7细胞体外侵袭能力的影响.结果 转染anti-pCR3.1-Ezrin后,对MDA-MB-231细胞中的Ezrin表达抑制在24 h时达高峰.MTT法比色实验结果显示,MDA-MB-231和MCF-7细胞中转染anti-pCR3.1-Ezrin组、转染空质粒组和对照组的A值分别为0.410±0.018、0.765±0.058、0.795±0.061和0.480±0.021、0.632±0.052、0.648±0.059.转染anti-pCR3.1-Ezrin组细胞的增殖受到明显抑制,抑制率分别为(47.9±3.1)%和(32.0±2.8)%(P<0.05).Boyden小室法检测结果显示,MDA-MB-231和MCF-7细胞中转染anti-pCR3.1-Ezrin组细胞的侵袭能力分别为对照组的(50.5±3.2)%和(74.8±4.6)%(P<0.05).结论 Ezrin在乳腺癌的生长和侵袭过程中发挥重要作用.     

肿瘤相关钙信号传导蛋白-2基因对人乳腺癌细胞黏附和侵袭力的影响

目的 观察肿瘤相关钙信号传导蛋白-2(TROP-2)基因小干扰RNA (siRNA)对乳腺癌细胞黏附和侵袭力的影响.方法 培养人乳腺癌Bcap-37、LCC1、MCF-7、MDA-MB-231、MDA-MB-435、MDA-MB-468及ZR75-1细胞株,以荧光实时定量聚合酶链反应(PCR)方法检测TROP-2基因mRNA表达;筛选出TROP-2表达最高者.采用TROP4基因siRNA转染乳腺癌细胞,分别以荧光实时定量RT-PCR和免疫荧光方法观察TROP-2基因mRNA和蛋白水平,然后以噻唑蓝(MTT)比色法检测细胞黏附性,以Transwell方法检测癌细胞侵袭能力.结果 人乳腺癌Bcap-37、LCC1、MCF-7、MDA-MB-231、MDA-MB-35、MDA-MB-468及ZR75-1细胞株TROP-2 mRNA分别是1.362±0.057、2.207±0.056、2.997±0.052、0.136±0.045、0.122±0.025、0.194±0.028和2.706±0.039,以MCF-7细胞最高;以TROP-2 siRNA转染乳腺癌MCF-7细胞后,癌细胞TROP-2基因mRNA和蛋白水平明显下降,且呈浓度依赖性;黏附实验结果显示,5、10、20 nmol/L siRNA组黏附率分别为(52.9±2.5)％、(25.6±2.3)％、(12.8±2.2)％(P＜0.01);Transwell实验结果显示,5、10和20 mol/L siRNA组穿过滤膜的细胞分别为78±17、39±15、19±16,而对照组分别为136±25、139±21(P＜0.01).结论 TROP-2基因在乳腺癌细胞黏附和侵袭中发挥着重要作用;以siRNA转染乳腺癌细胞,可抑制乳腺癌细胞黏附和侵袭能力.     

畸胎瘤细胞源性生长因子对雌激素受体阴性乳腺癌细胞雌激素依赖性的影响

目的分析乳腺癌细胞雌激素依赖性与畸胎瘤细胞源性生长因子（PC—cell derived growth factor,PCDGF）表达之间的关系,探讨雌激素受体（ER）阴性乳腺癌患者接受内分泌治疗的可能性。方法荧光定量聚合酶链反应检测乳腺癌细胞系MCF-7、MDA-MB-231、T47D、MDA-MB-435s中PCDGF的表达,CCK-8法检测不同浓度雌激素培养条件下细胞的存活情况。以ER阳性乳腺癌细胞系MCF-7为对照,用RNA干扰技术抑制ER阴性乳腺癌细胞系MDA-MB-231中PCDGF基因的表达,观察抑制前后雌激素依赖性的变化。结果PCDGF在4株乳腺癌细胞系中均有不同程度的表达,其中在MDA-MB-435s中表达量最高,PCDGF高表达的乳腺癌细胞系的雌激素依赖性较高,PCDGFshRNA可以有效抑制乳腺癌细胞系MCF-7和MDA-MB-213中PCDGF的表达（抑制率分别为81．1％和86．7％）。MDA-MB-231细胞系雌激素依赖性增加的程度高于MCF-7细胞系（P〈0．05）。结论PCDGF高表达于ER阴性乳腺癌细胞,抑制其表达可能会更好的逆转内分泌治疗的耐药性。     

RNA干扰下调midkine基因表达对人乳腺癌细胞粘附和侵袭力的影响

目的 探讨中期因子(midkine,MK)基因siRNA对乳腺癌细胞生物学行为的影响.方法 培养人乳腺癌Bcap-37、LCCI、MCF-7、MDA-MB-231、MDA-MB-435、MDA-MB-468及ZR75-1细胞株,以荧光实时定量PCR方法检测MK基因mRNA表达;筛选出MK表达最高者.采用MK siRNA...     

尿多酸肽对乳腺癌细胞凋亡的影响

目的研究肿瘤细胞分化诱导剂尿多酸肽（CDA—Ⅱ）对乳腺癌细胞凋亡的影响。方法将CDA—Ⅱ与不同生物学特性的乳腺癌细胞株MCF-7和MDA-MB-231进行体外培养，同时以维甲酸为阳性对照，观察CDA—Ⅱ对乳腺癌细胞生长曲线、细胞凋亡及形态学等方面的影响。结果CDA—Ⅱ可减缓两株乳腺癌细胞的生长和增殖能力，诱导乳腺癌细胞凋亡。结论CDA—Ⅱ可抑制MCF-7和MDA-MB-231两株乳腺癌细胞的生长和增殖能力，诱导乳腺癌细胞凋亡．本研究为CDA-Ⅱ治疗乳腺痛提供了实验依据。     

基质金属蛋白酶-2和纤维粘连蛋白在乳腺癌细胞系的定量表达

目的分析乳腺癌细胞系的基质金属蛋白酶-2(MMP-2)和纤维粘连蛋白(FN)mRNA表达及蛋白表达与乳腺癌转移的关系，阐明MMP-2和FN在乳腺癌转移中的作用。方法采用荧光定量逆转录-聚合酶链反应(RT—PCR)检测乳腺癌细胞系的MMP-2和FN mRNA表达量；采用Western blot方法检测细胞系的MMP-2和FN蛋白表达量。结果MMP-2和FN的mRNA表达量在乳腺癌高转移细胞系MDA-MB-231、MDA-MB-435中表达下调，而在低转移细胞系MDA-453、T47D、SK-BR-3和不转移细胞系MCF-7、ZR-75-30表达上调。MMP-2和FN蛋白表达在高转移细胞系上调，而在低转移细胞系和不转移细胞系中下调。结论MMP-2和FN mRNA表达和蛋白表达与乳腺癌转移相关，MMP-2和FN mRNA水平和蛋白水平的表达存在负反馈调节。     

多种人乳腺癌细胞株CCL5表达和其侵袭能力关系的初步研究

目的探讨四种人乳腺癌细胞株（MCF-7，SK—BR-3，T-47D和MDA—MB-231）之间，CCL5表达与其侵袭能力间是否有相关性。方法使用RT—PCR方法和采用Cell Invasion Assay Kit分别测定四种人乳腺癌细胞株CCL5表达及其侵袭能力。结果CCL5基因在四种细胞株中均有表达，其中MCF-7细胞株中该基因表达量相对较高，MDA—MB-231和T47-D细胞株次之，SK—BR-3细胞株表达量相对较低。MDA—MB-231细胞株侵袭能力最强，SK—BR-3细胞株次之，MCF-7、T-47-D细胞株侵袭能力弱。结论在四种人乳腺癌细胞株之间，尚未发现CCL5 mRNA表达量与其侵袭能力间有明显的线性相关性。该研究为进一步探讨CCL5和乳腺癌的关系提供新方向。