摘要
目的观察5氮2脱氧胞苷(5-AZA-CDR)对雌激素受体Α(ERΑ)阴性人类乳腺癌细胞株MDA-MB-231和MDA-MB-435ERΑ基因诱导表达作用;5-AZA-CDR联合三苯氧胺(TAM)对ERΑ阴性乳腺癌细胞的体外抑制作用。方法应用甲基化特异性PCR(MSP)检测MDA-MB-231和MDA-MB-435细胞和20例ERΑ阴性乳腺癌组织ERΑ基因核心启动子区CPG岛甲基化情况;5-AZA-CDR处理MDA-MB-231和MDA-MB-435细胞,逆转录PCR(RT-PCR)检测ERΑMRNA表达;5-AZA-CDR、TAM分别或联合作用于MDA-MB-231和MDA-MB-435细胞,MTT比色法分析细胞生长抑制作用,流式细胞仪测定细胞周期分布和凋亡率。结果适当浓度的5-AZA-CDR能诱导MDA-MB-231和MDA-MB-435细胞表达ERΑMRNA,抑制细胞生长、阻滞细胞周期于G0/G1期,诱导细胞凋亡;TAM对MDA-MB-231和MDA-MB-435细胞生长、细胞周期无影响;而两药联合时能显著抑制细胞生长,诱导细胞凋亡,凋亡率分别为48.8%和53.1%。结论5-AZA-CDR能诱导ERΑ阴性乳腺癌表达ERΑMRNA,恢复ERΑ阴性乳腺癌细胞对TAM的敏感性,联合TAM能协同抑制ERΑ阴性乳腺癌细胞生长,诱导细胞凋亡,从而为ERΑ阴性乳腺癌开辟新的内分泌治疗途径提供实验依据。
Objective To observe if ER alpha gene can be induced by 5-aza-CdR in ER alpha negative human breast cancer cell lines （MDA-MB-231 and MDA-MB-435 ） and the synergistic inhibitory effects of 5-aza-CdR and Tamoxifen on these two cell lines in vitro. Methods The status of 5CpG island methylation of ER alpha gene in ER alpha negative （MDA-MB-231 and MDA-MB-435） human breast cancer cell lines and 20 cases of breast cancer tissue was studied by MSP, the expression of ER alpha mRNA was inspected by using RT-PCR after these two cell lines were treated with 5-aza-CdR. Cell proliferation was evaluated by MTT assay, distribution of cell cycle and rate of apoptosis were determined by flow cytometry after these two cell lines were treated with 5-aza-CdR or TAM alone, or in combination in vitro. Results The 5＇CpG island is methylated in the core promotor of ER alpha gene in ER alpha negative （MDA-MB-231 and MDA-MB-435 ） human breast cancer cell lines and the methylating rate is 25.0% , 66. 7% , 83.3% , 100% in 20 cases of breast cancer tissue of stage Ⅰ,Ⅱ,Ⅲ, Ⅳ, respectively. The expression of ER alpha mRNA was induced in these two cell lines after treated with 5-aza-CdR, MTT array showed the proliferation activity of these two cell lines was obviously reduced in 5-aza-CdR group and the inhibitory effect on proliferation was enhanced when 5-aza-CdR combined with TAM compared with control group, the induction of apoptosis was 11.20% and 8. 71% respectively by 5-aza-CdR,while the rate of apoptosis is 48.8% and 53.1% when these two cells were treated with 5-aza-CdR combined with TAM. Conclusions 5-aza-CdR can re-express ER alpha by demethylating and sensitive ER alpha negative human breast cancer cell lines to TAM ,5-aza-CdR and TAM synergistically inhibite proliferation and induce apoptosis in ER alpha negative human breast cancer cell lines ,thus offer a new way for the treatment of ER alpha negative breast cancer.
出处
《中华外科杂志》
CAS
CSCD
北大核心
2005年第23期1545-1549,共5页
Chinese Journal of Surgery
关键词
乳腺肿瘤
受体
雌激素
脱氧胞苷
甲基化
三苯氧胺
Breast neoplasms
Receptors, estrogen
Deoxycytidine
Methylation
Tamoxifen
