The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan Province 453100, PR China.
Oncol Rep. 2012 Oct;28(4):1193-9. doi: 10.3892/or.2012.1910. Epub 2012 Jul 13.
Gelatinases play an important role in tumor growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumors. Lidamycin is an enediyne antitumor antibiotic with potent cytotoxicity. We previously reported that a tandem scFv format (dFv-LDP-AE) showed enhanced binding ability with gelatinases compared with the scFv-lidamycin conjugate (Fv-LDP-AE). In this study, the antitumor activities of dFv-LDP-AE on hepatocellular carcinoma (HCC) were evaluated in vitro and in vivo. By SDS-PAGE analysis, it was found that partial fusion protein dFv-LDP existed as dimer; the results of ELISA and immunofluorescence demonstrated that the fusion protein dFv-LDP could efficiently bind to hepatoma cells in vitro. The apparent arrest of cell cycle at G2/M phase and induction of apoptosis at nanomole levels indicated that the dFv-LDP-AE was very potent against HCC. In in vivo experiments, dFv-LDP-AE shown enhanced cytotoxic effects compared to those of LDM. Administration at mouse tolerable dosage level, the inhibition rate of tumor growth was 89.5% of dFv-LDP-AE vs. 73.6% of LDM on transplantable H22 in mice (P<0.05) and, 87.3% of dFv-LDP-AE vs. 63.4% of LDM on hepatoma Bel-7402 in athymic mice (P<0.01). Small animal optical imaging showed that the FITC-labeled dFv-LDP preferentially localized in the tumor site in less than 30 min, which demonstrated remarkable tumor-targeting properties. Taken together with the above findings, the enediyne-energized fusion protein dFv-LDP-AE showed potential application as a new agent for therapeutic appications in HCC.
明胶酶在肿瘤生长和转移中发挥重要作用，这些分子的过度表达与多种恶性肿瘤的预后不良密切相关。力达霉素是一种具有强大细胞毒性的烯二炔类抗肿瘤抗生素。我们之前报道过，串联 scFv 形式（dFv-LDP-AE）与 scFv-力达霉素缀合物（Fv-LDP-AE）相比，具有更强的与明胶酶结合的能力。在这项研究中，评估了 dFv-LDP-AE 对肝癌（HCC）的体内外抗肿瘤活性。通过 SDS-PAGE 分析，发现部分融合蛋白 dFv-LDP 以二聚体形式存在；ELISA 和免疫荧光结果表明，融合蛋白 dFv-LDP 能够在体外有效地与肝癌细胞结合。细胞周期明显停滞在 G2/M 期，凋亡在纳摩尔水平诱导，表明 dFv-LDP-AE 对 HCC 非常有效。在体内实验中，dFv-LDP-AE 与 LDM 相比显示出增强的细胞毒性作用。在耐受剂量水平下给药时，dFv-LDP-AE 对移植性 H22 小鼠的肿瘤生长抑制率为 89.5%，而 LDM 为 73.6%（P<0.05），dFv-LDP-AE 对裸鼠 Bel-7402 肝癌的抑制率为 87.3%，而 LDM 为 63.4%（P<0.01）。小动物光学成像显示，FITC 标记的 dFv-LDP 在不到 30 分钟内优先定位在肿瘤部位，表现出显著的肿瘤靶向特性。综上所述，烯二炔类激活的融合蛋白 dFv-LDP-AE 作为一种新的治疗 HCC 的药物具有潜在的应用价值。
