热诱导视网膜母细胞瘤细胞凋亡及阿斯匹林对热凋亡的保护作用

Hyperthermia induced apoptosis and the protective effect of aspirin in retinoblastoma

目的 研究视网膜母细胞瘤的热凋亡现象及阿斯匹林对视网膜母细胞瘤热凋亡的影响。 方法 将视网膜母细胞瘤Ｙ７９细胞分为单纯加热组及加热＋ 阿斯匹林组。加热条件：４４℃水浴，加热时间分别为１０，２０，３０，４０分钟。阿斯匹林浓度为０１８，１８，１８ μｇ／ｍ ｌ。分别测定细胞凋亡；热休克蛋白７０的表达；ｂｃｌ２蛋白的表达。 结果 ４４℃加热可诱导视网膜母细胞瘤Ｙ７９细胞凋亡，并呈剂量依赖性。当加热超过一定范围（４４℃，４０分钟）细胞主要表现为坏死。阿斯匹林可抑制热诱导的Ｙ７９ 细胞的凋亡，也呈剂量依赖性。Ｙ７９ 细胞经４４℃３０ 分钟加热后，热休克蛋白７０ 表达增强，阿斯匹林（１８ μｇ／ｍｌ以上）可进一步增加Ｙ７９细胞热休克蛋白７０的表达。加热对Ｙ７９细胞ｂｃｌ２的表达无明显影响，阿斯匹林在加热状态下可增加Ｙ７９细胞ｂｃｌ２的表达。 结论 加热在一定范围内可诱导Ｙ７９ 细胞凋亡，阿斯匹林对热诱导的Ｙ７９细胞凋亡有保护作用，可能与其增加Ｙ７９ 细胞热休克蛋白７０及ｂｃｌ２的表达有关。

Objective To study hyperthermia induced apoptosis and the effect of aspirin on hyperthermia induced apoptosis in retinoblastoma cells. Methods Retinoblastoma cells (Y79) were divided into two groups:hyperthermia groups,hyperthermia+aspirin (0.18～18 μg/ml) groups.Heat shock condition:44℃,heat shock time:10,20,30,and 40 minutes respectively.The following events were studied after heat shock by using FAC Scan:① cell apoptosis;② heat shock protein 70 (HSP70) expression; ③ bcl 2 expression. Results Apoptosis was induced by the treatment of hyperthermia (44℃) in Y79 cells in a heat dose dependent fashion.Longer time heating (44℃,40 minutes) induced necrosis rather than apoptosis. Aspirin could rescue Y79 cells from hyperthermia induced apoptosis in a dose dependent manner.HSP70 was induced in Y79 cells after heat shock,it was further enhanced by the treatment of aspirin (>1.8 μg/ml).Heat shock itself showed no effect on bcl 2 expression in Y79 cells,aspirin,on the other hand,could enhance bcl 2 expression in a modest level in heat treated Y79 cells. Conclusions Hyperthermia may induce apoptosis in Y79 cells which can be protected by use of aspirin.The enhancement of HSP70 and bcl 2 expression in Y79 cells by the treatment of aspirin in heating condition may be responsible for the protective function.