Yoon A-Rum, Kim Joo-Hang, Lee Young-Sook, Kim Hoguen, Yoo Ji-Young, Sohn Joo-Hyuk, Park Byeong-Woo, Yun Chae-Ok
Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, South Korea.
Hum Gene Ther. 2006 Apr;17(4):379-90. doi: 10.1089/hum.2006.17.379.
Oncolytic adenoviruses are currently being developed as novel antitumor therapeutics. To enhance their therapeutic potential, adenoviruses are being administered in combination with standard chemotherapy. Adenoviral vectors used in these clinical trials, however, can be destructive as they encode intact E1B 19-kDa protein, which can block the apoptotic pathway induced by a variety of chemotherapeutic agents. Previously, we have shown that oncolytic adenovirus Ad-DeltaE1B19/55, deleted for sequence encoding E1B 19-kDa and E1B 55-kDa proteins, exhibits marked enhancement in cytolytic and apoptotic activity [Kim, J., Cho, J.Y., Kim, J.H., Jung, K.C., and Yun, C.O. (2002). Cancer Gene Ther. 9, 725-736]. In the current study, we assess the therapeutic value of Ad- DeltaE1B55 and Ad-DeltaE1B19/55 in combination with cisplatin. A marked increase in cytotoxicity was observed for both Ad-DeltaE1B55 and Ad-DeltaE1B19/55 when combined with cisplatin. Relative to each other in all cell lines examined, the combination of the double-deleted adenovirus, Ad-DeltaE1B19/55, plus cisplatin exhibited a greater cell-killing effect than did the single-deleted adenovirus, Ad-DeltaE1B55, plus cisplatin. Propidium iodide staining and TUNEL analysis also revealed that the combination of cisplatin with Ad-DeltaE1B19/55 caused greater induction of apoptosis than that with Ad-DeltaE1B55. Similarly, in vivo, the combination of Ad-DeltaE1B55 or Ad-DeltaE1B19/55 with cisplatin also induced greater antitumor effect in a human cervical xenograft model. TUNEL staining showed that the apoptotic level was significantly higher in tumor tissue treated with Ad-DeltaE1B19/55 plus cisplatin than with any other treatment. In addition, viral presence was confirmed by immunohistological staining, with increased numbers of adenoviral particles detected in wider areas of tumors treated with Ad-DeltaE1B19/55 oncolytic adenovirus plus cisplatin. Taken together, these findings demonstrate that cisplatin in combination with E1B- 19kD-deleted oncolytic adenovirus may enhance therapeutic efficacy (via active induction of apoptosis), eliciting a greater efficacy profile than that with E1B-19kD-expressing oncolytic adenovirus.
溶瘤腺病毒目前正作为新型抗肿瘤治疗药物进行研发。为增强其治疗潜力，腺病毒正与标准化疗联合使用。然而，这些临床试验中使用的腺病毒载体可能具有破坏性，因为它们编码完整的E1B 19 kDa蛋白，该蛋白可阻断多种化疗药物诱导的凋亡途径。此前，我们已经表明，缺失编码E1B 19 kDa和E1B 55 kDa蛋白序列的溶瘤腺病毒Ad-DeltaE1B19/55在细胞溶解和凋亡活性方面有显著增强[Kim, J., Cho, J.Y., Kim, J.H., Jung, K.C., and Yun, C.O. (2002). Cancer Gene Ther. 9, 725 - 736]。在本研究中，我们评估了Ad-DeltaE1B55和Ad-DeltaE1B19/55与顺铂联合使用的治疗价值。当Ad-DeltaE1B55和Ad-DeltaE1B19/55与顺铂联合使用时，观察到细胞毒性显著增加。在所有检测的细胞系中，与单缺失腺病毒Ad-DeltaE1B55加顺铂相比，双缺失腺病毒Ad-DeltaE1B19/55加顺铂的组合表现出更大的细胞杀伤作用。碘化丙啶染色和TUNEL分析还显示，顺铂与Ad-DeltaE1B19/55联合使用比与Ad-DeltaE1B55联合使用诱导的凋亡更多。同样，在体内，Ad-DeltaE1B55或Ad-DeltaE1B19/55与顺铂联合使用在人宫颈异种移植模型中也诱导了更大的抗肿瘤作用。TUNEL染色显示，用Ad-DeltaE1B19/55加顺铂治疗的肿瘤组织中的凋亡水平明显高于其他任何治疗组。此外，通过免疫组织化学染色证实了病毒的存在，在用Ad-DeltaE1B19/55溶瘤腺病毒加顺铂治疗的肿瘤更广泛区域检测到腺病毒颗粒数量增加。综上所述，这些发现表明，顺铂与缺失E1B - 19kD的溶瘤腺病毒联合使用可能会提高治疗效果（通过主动诱导凋亡），比表达E1B - 19kD的溶瘤腺病毒产生更大的疗效。
