Fukuhara Hirokazu, Hayashi Yasushi, Yamamoto Noriyuki, Fukui Takafumi, Nishikawa Masaya, Mitsudo Kenji, Tohnai Iwai, Ueda Minoru, Mizuno Masaaki, Yoshida Jun
Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya 466-8550, Japan.
Oral Oncol. 2003 Sep;39(6):601-9. doi: 10.1016/s1368-8375(03)00047-2.
Adenovirus (Ad) vectors are commonly used in gene therapy trials because of their efficiency in gene transfer. However, their use is limited by immune responses that reduce transgene expression and decrease the efficiency of repeated vector administration. In this study, the efficacy of gene transduction and the tumor-cell killing effect on four human oral (SAS, HSC-2, HSC-3, HSC-4) and one murine squamous cell carcinoma cell (SCC-7, a kind gift of Dr. M. Hiraoka, Kyoto University) lines in vitro with Ad vector conjugated with catioic liposome (Ad/SUV) was evaluated. Ad/SUV resulted in two to five-fold over higher transduction efficiency in four human and one murine cell lines in vitro than Ad vector alone. The optimal Ad-SUV ratio was determined as 10(6) pfu of Ad vector with 1 micromol SUV. Ad/SUV showed more tumor-cell killing effect than Ad vector alone. Furthermore, the shielding effects of Ad vector with Ad/SUV from neutralizing antibody were evaluated. We also found that Ad/SUV is less susceptible to inactivation by neutralizing antibodies in vitro. The efficacy of gene transduction with Ad vector was blocked more than 70% with neutralizing serum, while Ad/SUV retained approximately 50% of the control activity in vitro. On the basis of these results, the anti-tumor effect with suicide gene therapy using Ad/SUV in vivo was evaluated. Three injections of Ad/SUV showed the inhibition of tumor growth compared with control in vivo. Our results suggested that an enhanced anti-tumor effect on human oral squamous cell carcinoma would be obtained with repeated administrations of Ad/SUV.
腺病毒（Ad）载体因其高效的基因转移能力而常用于基因治疗试验。然而，其应用受到免疫反应的限制，免疫反应会降低转基因表达并降低重复载体给药的效率。在本研究中，评估了阳离子脂质体偶联的腺病毒载体（Ad/SUV）对四种人类口腔癌细胞系（SAS、HSC-2、HSC-3、HSC-4）和一种小鼠鳞状细胞癌细胞系（SCC-7，由京都大学的平冈博士惠赠）的基因转导效率和肿瘤细胞杀伤作用。与单独的腺病毒载体相比，Ad/SUV在体外对四种人类细胞系和一种小鼠细胞系的转导效率高出两到五倍。确定最佳的Ad-SUV比例为10(6) 个腺病毒载体空斑形成单位（pfu）与1微摩尔SUV。Ad/SUV比单独的腺病毒载体表现出更强的肿瘤细胞杀伤作用。此外，还评估了Ad/SUV对腺病毒载体的中和抗体屏蔽作用。我们还发现Ad/SUV在体外对中和抗体的灭活作用更具抗性。用中和血清处理后，腺病毒载体的基因转导效率被阻断超过70%，而Ad/SUV在体外仍保留约50%的对照活性。基于这些结果，评估了在体内使用Ad/SUV进行自杀基因治疗的抗肿瘤效果。与对照组相比，三次注射Ad/SUV显示出对体内肿瘤生长的抑制作用。我们的结果表明，重复给药Ad/SUV可增强对人类口腔鳞状细胞癌的抗肿瘤作用。
