热化疗对小鼠移植性S180肉瘤细胞凋亡、增殖及血管生成的影响

摘要

目的 探讨热疗联合化疗对小鼠S180肉瘤模型细胞凋亡、增殖及血管生成的影响.方法 建立荷瘤小鼠模型,随机分为对照组、化疗组、热疗组和热化疗组,化疗组予以平阳霉素0.2mg/只,热疗组予以(43±0.2)℃水浴1h,热化疗组同时予以化疗+热疗,每4天1次,重复3次.治疗结束后,取瘤体,测瘤重,计算抑瘤率,流式细胞仪测定肿瘤细胞周期、凋亡率及增殖细胞核抗原(PCNA)蛋白含量,RT-PCR检测血管内皮生长因子(VEGF) mRNA、PCNA mRNA,免疫组化法检测VEGF蛋白,计数微血管密度(MVD)值.结果 S期细胞对热疗最敏感.化疗组、热疗组和热化疗组均可抑制小鼠S180肉瘤的生长,细胞凋亡率均较对照组高(P＜0.05),PCNA、VEGF蛋白表达和MVD均较对照组降低(P＜0.05),其中热化疗组变化最显著(P＜0.05).RT-PCR检测VEGF mRNA、PCNA mRNA亦得到上述同样结果.直线相关性分析示,VEGF蛋白表达与MVD呈正相关(r=0.915,P＜0.01).结论 热疗可以诱导S180细胞凋亡,抑制PCNA、VEGF表达,使MVD下降.热疗与化疗联合具有协同作用,显著提高对S180肉瘤的疗效.%Objective To study effects of chemohyperthermia on apoptosis, proliferation and angiogenesis of mice models transplanted with sarcoma S180 cells. Methods S180 tumor-bearing mice models were established and randomly assined into 4 groups: control group, hyperthermia group, chemotherapy group and chemohyperthrmia group. Hyperthermia(43 ±0. 2℃ waterbath for 1 hour), chemotherapy (pingyangmycin 0. 2mg for a mouse) and chemohyperthermia (combine the methods mentioned before) were given respectinely. Treatment was reparted every 4 days for 3 times. Then subcutaneous tumors were processed for weight and inhibition rate. Cell apoptosis, cell cycle and the expression of PCNA protein were detected and analyzed by FCM. The expression levels of PCNA mRNA and VEGF mRNA were detected with semiquantity RT-PCR. VEGF and MVD were measured by immunohistechemical staining. Results The cells in “S” phase were more sensitive to hyperthermia. Compared with the control group,all of the experimental groups inhibited sarcoma S180 cells growing,the apoptosis rates of them were increased and the PCNA, VEGF and MVD of them were decreased,especially in the chemohyperthermia group. The changes of PCNA and VEGF in genes also verified the results, and findings demonstrated a significant positive correlation between VEGF and MVD ( r = O. 915, P ＜ 0. Ol ). Conclusion Hyperthermia can induce apoptosis of sarcoma S180 cells, restrain their producing of PCNA and VEGF protein to inhibit proliferation and angiogenesis.Chemohyperthermia can improve tumor cells sensitivity to chemotherapeutics and become a better therapy for tumor patients.