β-羟基异戊酰紫草素对人肺癌A549裸鼠移植瘤生长的影响及其机制研究

Effect of β-hydroxyisovaleryl shikonin on growth of lung adenocarcinoma cells A549 in nude mice and its mechanism

目的探讨β-羟基异戊酰紫草素(β-HIVS)对人肺癌A549裸鼠移植瘤生长的影响,并探讨其可能机制。方法建立人肺癌裸鼠移植瘤模型,随机分为对照组,β-HIVS低、中、高剂量(10、20、40 mg/kg)组和紫杉醇(30 mg/kg)组,每组6只。各组ip给药,每次0.2 m L,每周2次,连续用药4周。检测裸鼠体质量、肿瘤体积、瘤质量等,绘制肿瘤生长曲线,并计算抑瘤率。TUNEL法检测β-HIVS处理后各组移植瘤组织中的细胞凋亡情况;免疫组化法、Westernblotting和实时荧光定量PCR技术(qRT-PCR)检测各组移植瘤组织中p53、Bcl-2蛋白和m RNA的表达。结果β-HIVS能够较好地抑制肺癌裸鼠移植瘤的生长,能明显缩小肿瘤体积,且呈剂量依赖性。TUNEL法显示β-HIVS处理后肿瘤细胞凋亡较对照组明显增多。免疫组化结果显示β-HIVS处理后移植瘤组织中p53蛋白表达有升高的趋势,而Bcl-2蛋白表达有降低的趋势。Westernblotting和q RT-PCR结果与免疫组化有相同的变化趋势。结论β-HIVS对人肺癌A549裸鼠移植瘤具有明显的抑制作用,其机制可能与上调p53的表达和下调Bcl-2的表达,诱导肺癌细胞凋亡有关。

Objective To study the effects of β-hydroxyisovaleryl shikonin(β-HIVS) on the growth of human lung cancer A549 cells in nude mice and explore its mechanism. Methods Thirty mice with subcutaneous xenografts of a lung cancer cell line(A549) were randomly divided into five groups: negative control group, positive control group(paclitaxel), and low-dose, medium-dose, and high-dose β-HIVS groups(10, 20, and 40 mg/kg, respectively). There were six mice in each group. Tumor volume, tumor weight, and body weight were measured to draw up tumor growth curves and the tumor weight inhibition rates were calculated. The apoptosis rates were measured by TUNEL staining method. The protein and m RNA expression of p53 and Bcl-2 were assessed by immunohistochemical staining, Western blot, and quantitative real-time PCR analysis. The mice in each group were administrated with β-HIVS(0.2 mL, ip) twice each week for four consecutive weeks. Results The β-HIVS could inhibit the growth of A549 xenografts in a dose-dependent manner. TUNEL assay showed that the apoptotic rate of tumor cells in β-HIVS-treated mice were significantly higher than the negative control group. The protein and mRNA expression of p53 was up-regulated, while the expression of Bcl-2 was down-regulated in nude mice after the treatment with β-HIVS. Conclusion β-HIVS significantly inhibited the growth of A549 cell xenografts in nude mice, which might be related with the up-regulation of p53 expression and down-regulation of Bcl-2 expression.