Denlinger Chadrick E, Rundall Brian K, Jones David R
Department of Thoracic and Cardiovascular Surgery, University of Virginia, Charlottesville, VA 22908, USA.
J Thorac Cardiovasc Surg. 2004 Nov;128(5):740-8. doi: 10.1016/j.jtcvs.2004.07.010.
The histone deacetylase inhibitor suberoylanilide hydroxamic acid induces apoptosis in some malignancies through mitochondrial injury and generation of reactive oxygen species. Histone deacetylase inhibitors also activate the antiapoptotic transcription factor nuclear factor kappaB. We hypothesize that proteasome inhibition with bortezomib (Velcade; Millennium Pharmaceuticals, Inc, Cambridge, Mass)will inhibit nuclear factor kappaB activation, enhance suberoylanilide hydroxamic acid-induced mitochondrial injury, and sensitize non-small cell lung cancer cells to apoptosis.
Four tumorigenic non-small cell lung cancer cell lines were treated with nothing, suberoylanilide hydroxamic acid, bortezomib, or both drugs. Nuclear factor kappaB-dependent transcription was determined by reporter gene assays and endogenous interleukin 8 transcription. Reactive oxygen species were quantified by using the fluorophore H 2 DCFDA. Cell viability was determined on the basis of clonogenic survival, and apoptosis was measured by quantifying caspase-3 activity and DNA fragmentation. Apoptosis and cell-survival assays were repeated in similarly treated cells incubated in the presence or absence of N-acetyl cysteine. Statistical significance was determined by means of analysis of variance.
Suberoylanilide hydroxamic acid significantly enhanced interleukin 8 and nuclear factor kappaB-dependent reporter gene transcription, and these effects were inhibited by bortezomib ( P < or = .01). Combined treatment with suberoylanilide hydroxamic acid and bortezomib induced greater reactive oxygen species generation, more apoptosis ( P < or = .02), and more cell death ( P < or = .001) than either drug alone. N-acetyl cysteine diminished the induction of apoptosis and enhanced cell survival ( P < or = .04).
Suberoylanilide hydroxamic acid and bortezomib synergistically induce reactive oxygen species generation in non-small cell lung cancer, and this plays a critical role in the induction of apoptosis after treatment. Combined treatment with suberoylanilide hydroxamic acid and bortezomib might be an effective treatment strategy for non-small cell lung cancer.
组蛋白去乙酰化酶抑制剂辛二酰苯胺异羟肟酸通过线粒体损伤和活性氧生成在某些恶性肿瘤中诱导细胞凋亡。组蛋白去乙酰化酶抑制剂还可激活抗凋亡转录因子核因子κB。我们推测，用硼替佐米（万珂；千年制药公司，马萨诸塞州剑桥）抑制蛋白酶体将抑制核因子κB激活，增强辛二酰苯胺异羟肟酸诱导的线粒体损伤，并使非小细胞肺癌细胞对凋亡敏感。
用空白对照、辛二酰苯胺异羟肟酸、硼替佐米或两种药物处理四种致瘤性非小细胞肺癌细胞系。通过报告基因测定和内源性白细胞介素8转录来确定核因子κB依赖性转录。使用荧光团H2DCFDA对活性氧进行定量。根据克隆形成存活率确定细胞活力，并通过定量半胱天冬酶-3活性和DNA片段化来检测凋亡。在存在或不存在N-乙酰半胱氨酸的情况下，对经类似处理的细胞重复进行凋亡和细胞存活测定。通过方差分析确定统计学显著性。
辛二酰苯胺异羟肟酸显著增强白细胞介素8和核因子κB依赖性报告基因转录，而这些作用被硼替佐米抑制（P≤0.01）。与单独使用任何一种药物相比，辛二酰苯胺异羟肟酸和硼替佐米联合处理诱导产生更多的活性氧、更多的细胞凋亡（P≤0.02）和更多的细胞死亡（P≤0.001）。N-乙酰半胱氨酸减少了凋亡诱导并提高了细胞存活率（P≤0.04）。
辛二酰苯胺异羟肟酸和硼替佐米协同诱导非小细胞肺癌中活性氧的生成，这在治疗后诱导细胞凋亡中起关键作用。辛二酰苯胺异羟肟酸和硼替佐米联合治疗可能是非小细胞肺癌的一种有效治疗策略。
