Zhang Xiaochun, Cheung Rex Min, Komaki Ritsuko, Fang Bingliang, Chang Joe Y
Department of Experimental Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
Clin Cancer Res. 2005 Sep 15;11(18):6657-68. doi: 10.1158/1078-0432.CCR-04-2699.
To sensitize non-small cell lung cancer (NSCLC) to radiotherapy by tumor-specific delivery of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene.
The TRAIL was delivered to human NSCLC cell lines and normal human bronchial epithelial cells by the replication-defective adenoviral vector Ad/TRAIL-F/RGD using a tumor-specific human telomerase reverse transcriptase promoter. Cancer growth was studied using 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide inner salt and clonogenic assays. Activation of the apoptosis pathway was analyzed in a Western blot and sub-G(1) DNA accumulation. A xenograft mouse lung cancer model was treated by intratumoral injections of Ad/TRAIL-F/RGD and local radiotherapy; the other groups received one of these treatments alone or a control agent. Apoptosis and TRAIL expression in tumors were also analyzed.
Ad/TRAIL-F/RGD specifically targets human NSCLC cells without significant effect in normal human bronchial epithelial cells. The combination of Ad/TRAIL-F/RGD and radiotherapy significantly improved cell-killing effect in all NSCLC cell lines tested (P < 0.05). Expression of TRAIL showed a dose-dependent relationship with Ad/TRAIL-F/RGD, and radiation seemed to increase TRAIL expression. Activation of the apoptosis by TRAIL and radiation was shown by activation of caspase-9, caspase-8, caspase-3, and poly(ADP-ribose) polymerase and increased DNA sub-G(1) accumulation. The combination of TRAIL and radiotherapy significantly increased apoptosis in vivo, inhibited tumor growth, and prolonged mean survival in mice bearing human NSCLC to 43.7 days compared with 23.7 days (TRAIL only) and 16.5 days (radiotherapy only; P < 0.05).
The combination of Ad/TRAIL-F/RGD and radiotherapy significantly improved therapeutic efficacy in suppressing NSCLC tumor growth and prolonging survival. Ad/TRAIL-F/RGD may improve the therapeutic ratio of radiotherapy in NSCLC.
通过肿瘤特异性递送肿瘤坏死因子相关凋亡诱导配体（TRAIL）基因，使非小细胞肺癌（NSCLC）对放疗敏感。
使用肿瘤特异性人端粒酶逆转录酶启动子，通过复制缺陷型腺病毒载体Ad/TRAIL-F/RGD将TRAIL递送至人NSCLC细胞系和正常人支气管上皮细胞。使用2,3-双[2-甲氧基-4-硝基-5-磺基苯基]-2H-四唑-5-羧基苯胺内盐和克隆形成试验研究癌症生长。通过蛋白质印迹法和亚G1期DNA积累分析凋亡途径的激活情况。通过瘤内注射Ad/TRAIL-F/RGD和局部放疗治疗异种移植小鼠肺癌模型；其他组单独接受这些治疗之一或对照剂。还分析了肿瘤中的凋亡和TRAIL表达。
Ad/TRAIL-F/RGD特异性靶向人NSCLC细胞，对正常人支气管上皮细胞无明显影响。Ad/TRAIL-F/RGD与放疗联合在所有测试的NSCLC细胞系中显著提高了细胞杀伤效果（P<0.05）。TRAIL的表达与Ad/TRAIL-F/RGD呈剂量依赖性关系，并且辐射似乎增加了TRAIL的表达。通过半胱天冬酶-9、半胱天冬酶-8、半胱天冬酶-3和聚（ADP-核糖）聚合酶的激活以及DNA亚G1期积累增加，显示了TRAIL和辐射对凋亡的激活作用。TRAIL与放疗联合在体内显著增加凋亡，抑制肿瘤生长，并将荷人NSCLC小鼠的平均生存期延长至43.7天，而单独使用TRAIL为23.7天，单独放疗为16.5天（P<0.05）。
Ad/TRAIL-F/RGD与放疗联合在抑制NSCLC肿瘤生长和延长生存期方面显著提高了治疗效果。Ad/TRAIL-F/RGD可能提高NSCLC放疗的治疗增益比。
