摘要
背景与目的:低氧作为实体瘤的特征和重要的生存微环境,可能与化疗耐药相关。我们认为低氧与卵巢癌化疗耐药可能相关。本研究建立低氧模型,探讨低氧、低氧诱导因子1α(HIF鄄1α)对紫杉醇诱导的人卵巢癌细胞A2780凋亡的影响。方法:体外培养的A2780细胞中加入化学性低氧诱导剂氯化钴(CoCl2),诱导并制作低氧模型。将细胞分为4组:A组(对照)、B组(常氧培养加紫杉醇)、C组(低氧培养加紫杉醇)、D组(低氧培养加Decoy加紫杉醇)。用诱骗法(Decoy)阻断HIF鄄1α功能,Westernblot、RT鄄PCR、TUNEL和流式细胞术分别检测各组细胞HIF鄄1α蛋白、mRNA的表达水平及细胞凋亡情况。结果:CoCl2能明显增加A2780细胞HIF鄄1α蛋白的表达,而对其mRNA的表达无明显影响,Decoy法阻断HIF鄄1α的功能,对其蛋白和mRNA的表达无明显影响。TUNEL检测发现,B组凋亡指数[AI:(41.12±25.65)%]显著高于C组[AI:(24.12±15.19)%](P<0.05);低氧阻断了HIF鄄1α功能后,D组凋亡指数[AI:(35.19±21.73)%]较C组明显增加(P<0.05)。流式细胞仪检测细胞凋亡率结果与TUNEL检测结果类似。结论:低氧能保护A2780细胞抵抗化学治疗,HIF鄄1α可能在紫杉醇诱导的细胞凋亡中发挥重要的抗凋亡作用。
BACKGROUND & OBJECTIVE: Hypoxia, a feature and important living micr oenvironment of solid tumors, might be related to drug-resistance of tumors. Thi s study was to establish a hypoxic model of ovarian cancer cell line A2780, and to investigate impacts of hypoxia and hypoxia inducible factor-1α (HIF-1α) on Taxol-induced apoptosis in A2780 cells. METHODS: Cobalt chloride (CoCl2), a chem ical hypoxia inducer, was added in A2780 cells to develop a hypoxic model. A2780 cells were divided into 4 groups: group A (control), group B (normoxia plus Tax ol), group C (hypoxia plus Taxol), and group D (hypoxia, Decoy plus Taxol). Deco y method was used to block the function of HIF-1α. Protein and mRNA levels of H IF-1α were detected by Western blot and reverse transcription-polymerase chain reaction (RT-PCR). Cell apoptosis was detected by TdT-mediated dUTP nick end lab eling (TUNEL), and flow cytometry (FCM). RESULTS: CoCl2 evidently increased prot ein level of HIF-1α, but had no effect on mRNA level of HIF-1α. Decoy didn't a ffect its expression. TUNEL showed that apoptotic index (AI) was significantly h igher in group B,and group D than in group C after treatment of Taxol <(41.1±25 .6)%,and (35.2±21.7)% vs. (24.1±15.2)%, P < 0.05>. The apoptosis rates detecte d by FCM displayed the same tendency as TUNEL results did. CONCLUSIONS: Hypoxia could weaken the effect of Taxol on inducing apoptosis of A2780 cells. HIF-1α m ight confer to resistance of cell apoptosis induced by Taxol.
出处
《癌症》
SCIE
CAS
CSCD
北大核心
2005年第4期408-413,共6页
Chinese Journal of Cancer
基金
国家杰出青年基金资助项目(No.30025017)
国家973重点基础科学基金资助项目(No.2002CB513107)~~
关键词
卵巢肿瘤
低氧
低氧诱导因子-1Α
凋亡
耐药
Ovarian neoplasms
Hypoxia
Hypoxia inducible factor-1α
Apoptosis
Drug-resistance