Kobayashi Minoru, Okada Takashi, Murakami Takashi, Ozawa Keiya, Kobayashi Eiji, Morita Tatsuo
Department of Urology, Jichi Medical University, Tochigi, Japan.
Urology. 2007 Dec;70(6):1230-6. doi: 10.1016/j.urology.2007.09.022.
Although the adenoviral vector represents an efficient delivery system, hepatotropic accumulation often has detrimental effects on adenoviral vector-mediated cancer therapy. To overcome this disadvantage, we performed in vivo local gene transfer, in combination with the histone deacetylase inhibitor, depsipeptide (FK228), in a rat renal cancer model.
Renal cancer cells induced by ferric nitrilotriacetate in ACI rats were used in this study. Adenoviral vectors containing luciferase cDNA were introduced into the tumor-burdened kidney by way of a catheter placed in the renal artery. Subcutaneous tumors were treated by herpes simplex virus thymidine kinase cDNA followed by intraperitoneal ganciclovir. The levels of Coxsackie-adenovirus receptor in various tissue were determined by quantitative reverse transcriptase-polymerase chain reaction. Depsipeptide (1 mg/kg) was intravenously administered 24 hours before adenoviral vector transduction.
The catheter-based adenoviral vector delivery enabled strong gene transduction of the tumor-burdened kidney. Moreover, depsipeptide treatment before adenoviral vector injection significantly improved transgene expression at tumor sites. Quantitative reverse transcriptase-polymerase chain reaction analysis showed that depsipeptide increased the expression levels of the Coxsackie-adenovirus receptor in the renal tumor (13-fold), but not in other normal tissues. Furthermore, the use of herpes simplex virus thymidine kinase cDNA-expressing adenoviral vector followed by ganciclovir markedly inhibited the established tumor growth in combination with depsipeptide compared with herpes simplex virus thymidine kinase cDNA alone.
The tissue-targeted in vivo gene transfer coupled with depsipeptide significantly enhanced adenoviral infection at tumor sites. Sensitization of tumor cells with depsipeptide can improve the efficacy of adenoviral vector-mediated suicide gene therapy. Thus, application of depsipeptide could be one of the beneficial adjunct for adenoviral vector-mediated cancer gene therapy.
尽管腺病毒载体是一种高效的递送系统，但嗜肝性积聚常常对腺病毒载体介导的癌症治疗产生有害影响。为克服这一缺点，我们在大鼠肾癌模型中进行了体内局部基因转移，并联合组蛋白去乙酰化酶抑制剂缩肽（FK228）。
本研究使用由三乙酸氮基铁在 ACI 大鼠中诱导产生的肾癌细胞。通过置于肾动脉的导管将携带荧光素酶 cDNA 的腺病毒载体导入荷瘤肾脏。皮下肿瘤用单纯疱疹病毒胸苷激酶 cDNA 处理，随后腹腔注射更昔洛韦。通过定量逆转录聚合酶链反应测定各种组织中柯萨奇病毒 - 腺病毒受体的水平。在腺病毒载体转导前 24 小时静脉注射缩肽（1mg/kg）。
基于导管的腺病毒载体递送能够使荷瘤肾脏实现强大的基因转导。此外，在腺病毒载体注射前进行缩肽处理可显著提高肿瘤部位的转基因表达。定量逆转录聚合酶链反应分析表明，缩肽增加了肾肿瘤中柯萨奇病毒 - 腺病毒受体的表达水平（13 倍），但在其他正常组织中未增加。此外，与单独使用单纯疱疹病毒胸苷激酶 cDNA 相比，使用表达单纯疱疹病毒胸苷激酶 cDNA 的腺病毒载体联合更昔洛韦，并与缩肽联合使用时，能显著抑制已形成肿瘤的生长。
组织靶向性体内基因转移联合缩肽可显著增强肿瘤部位的腺病毒感染。用缩肽使肿瘤细胞致敏可提高腺病毒载体介导的自杀基因治疗的疗效。因此，缩肽的应用可能是腺病毒载体介导的癌症基因治疗的有益辅助手段之一。
