阿司匹林诱导人恶性睾丸生殖细胞瘤NTera-2细胞凋亡

阿司匹林,又称乙酰水杨酸,已证实有抑制肿瘤细胞增殖、诱导肿瘤细胞凋亡和抑制血管生成等多种抗癌功能.除已知对环氧合酶COX-2的活性有抑制外，阿司匹林抗癌分子机制尚不十分清楚.已报道阿司匹林可以降低多种癌症发生风险，但应用于人类睾丸肿瘤治疗的研究报道很少.本文研究了阿司匹林对人恶性睾丸肿瘤NTera-2细胞凋亡的机制.通过MTT方法检测细胞活力，发现阿司匹林以时间和剂量依赖方式抑制NTera-2细胞增殖.不同浓度阿司匹林处理NTera-2细胞后，采用Hoechest 33258染色方法和Annexin V-FITC/PI流式法分别检测NTera-2细胞的形态学变化、凋亡小体形成、细胞凋亡水平；RT-PCR结果显示,NTera-2细胞中Fas和caspase-8的表达以阿司匹林剂量依赖性上升；蛋白印迹结果显示,FasL的蛋白表达水平下降并活化caspase-8、caspase-3蛋白表达，PARP出现剪切体. 进一步的实验证明,caspase广谱抑制剂Z-VAD-FMK能够减弱阿司匹林诱导NTera-2细胞凋亡. 结果显示，阿司匹林能明显抑制NTera-2细胞活力，并通过激活caspase 通路诱导NTera-2细胞的凋亡，为进一步利用阿司匹林治疗人类睾丸肿瘤的研究奠定基础.

Aspirin Induces Apoptosis in Cultured NTera-2 Human Malignant Testicular Germ Cells

Aspirin, also known as acetylsalicylic acid, has been shown to have anticancer effects with multiple activities, including inhibition of proliferation, induction of apoptosis, and inhibition of angiogenesis. The functional characteristics and the anti-tumor mechanism of aspirin are largely unknown, except for the suppression of cyclo-oxygenase 2 (COX-2). Aspirin administration is known to associate with lower risks of many cancer types, but less reported in human testicular tumors. We investigated on whether aspirin was able to induce apoptosis in NTera-2 human malignant testicular germ cells, using MTT to detected cell viabilities. The morphological changes, formation of apoptotic bodies, and cell apoptosis were assessed by fluorescence microscopy, Hoechest33342 staining, Annexin V-FITC/PI flow cytometry, RT-PCR and Western blotting were also performed. The result showed that aspirin inhibited the proliferation of NTera-2 cells in a dose- and time-dependent manner, and Fas and caspase-8 were up-regulated. The level of FasL was down-regulated after aspirin treatment. The protein levels of caspase-3, caspase-8, and poly(ADP-Ribose) polymerase (PARP) were increased. Caspase inhibitor Z-VAD-FMK could attenuate the aspirin–induced apoptosis. We concluded that the anticancer activity of aspirin was partially due to the inhibition of cell viability and induction of apoptosis associated with caspase apoptotic pathway.