Kudo Shigetaka, Konda Ryuichiro, Obara Wataru, Kudo Daisuke, Tani Kenzaburo, Nakamura Yusuke, Fujioka Tomoaki
Department of Urology, Iwate Medical University School of Medicine, Morioka 020-8505, Japan.
Oncol Rep. 2007 Oct;18(4):785-91.
This study was designed to elucidate the therapeutic effect of transfering the brain-specific angiogenesis inhibitor 1 (BAI1) gene to a mouse renal cell carcinoma cell line (Renca). Female BALB/c mice were inoculated subcutaneously with wild-type Renca (Renca/Wild) cells or Renca cells transfected with the BAI-1 (Renca/BAI-1) or LacZ (Renca/LacZ) gene. Tumor growth was observed every other day from 3 to 35 days after implantation. Moreover, the intratumoral injection of the adenovirus vector containing the gene encoding BAI1 was conducted at two-day intervals from 11 to 31 days after implantation of the Renca/Wild or Renca/BAI1 tumor. Tumor blood flow was measured by colorimetric angiogenesis assay (CAA). The concentration of the vascular endothelial growth factor (VEGF) in the cell culture supernatants was determined by enzyme-linked immunoassay. The size of the Renca/BAI1 tumor was significantly (p<0.01) suppressed compared to the Renca/Wild and Renca/LacZ tumors 21 days after tumor implantation. The injection of the BAI1 viral vector at 2-day intervals significantly inhibited the growth of both the Renca/Wild and Renca/BAI1 tumors. The blood volume measured by CAA and microvessel density was significantly lower in the Renca/BAI1 than in the Renca/Wild and Renca/LacZ tumors (p<0.01 and p<0.05, respectively). A significant (p<0.01) reduction in VEGF concentration in the supernatant was demonstrated in the Renca/BAI1 compared with the Renca/Wild and Renca/LacZ cell cultures. These observations suggest that the transfer of the BAI1 gene to Renca can suppress the tumor growth via the inhibition of angiogenesis. The down-regulation of VEGF production in tumor cells contributes to this anti-tumor effect.
本研究旨在阐明将脑特异性血管生成抑制因子1（BAI1）基因导入小鼠肾癌细胞系（Renca）的治疗效果。将野生型Renca（Renca/Wild）细胞或转染了BAI-1（Renca/BAI-1）或LacZ（Renca/LacZ）基因的Renca细胞皮下接种到雌性BALB/c小鼠体内。在植入后3至35天每隔一天观察肿瘤生长情况。此外，在Renca/Wild或Renca/BAI1肿瘤植入后11至31天，每隔两天进行一次含编码BAI1基因的腺病毒载体的瘤内注射。通过比色血管生成测定法（CAA）测量肿瘤血流量。采用酶联免疫吸附测定法测定细胞培养上清液中血管内皮生长因子（VEGF）的浓度。肿瘤植入21天后，与Renca/Wild和Renca/LacZ肿瘤相比，Renca/BAI1肿瘤的大小受到显著抑制（p<0.01）。每隔两天注射BAI1病毒载体可显著抑制Renca/Wild和Renca/BAI-1肿瘤的生长。通过CAA测量的血容量和微血管密度在Renca/BAI1肿瘤中显著低于Renca/Wild和Renca/LacZ肿瘤（分别为p<0.01和p<0.05）。与Renca/Wild和Renca/LacZ细胞培养相比，Renca/BAI1细胞培养上清液中VEGF浓度显著降低（p<0.01）。这些观察结果表明，将BAI1基因导入Renca可通过抑制血管生成来抑制肿瘤生长。肿瘤细胞中VEGF产生的下调有助于这种抗肿瘤作用。
