重组F3肽-铜绿假单胞菌外毒素A抑制肿瘤生长

 为检测重组的F3 肽-铜绿假单胞菌外毒素A（F3-PE39KDEL）的抗肿瘤作用，采用MTT 法检测F3-PE39KDEL 对人乳腺癌细胞MCF-7、人肺癌细胞A549、人卵巢癌细胞SKOV3 和人肝癌细胞HepG2 的生长抑制活性。采用半数致死剂量法观察F3-PE39KDEL 对小鼠的毒性反应。以接种人肺癌细胞的裸鼠为模型，观察F3-PE39KDEL 的抗肿瘤作用。结果显示，培养72、120 h时，F3-PE39KDEL对于人肺癌细胞A549和人乳腺癌细胞MCF-7具有显著的抑制活性，IC₅₀分别为0.41、0.42 μg/mL，4.95、2.53 μg/mL。毒性试验结果显示，静脉注射给予F3-PE39KDEL 后小鼠的半数致死量为1.1782 mg/kg，动物出现自发运动减少，死亡集中在给药后1 d 内，死亡动物及实验结束存活动物剖检未见异常。F3-PE39KDEL 对荷瘤裸鼠具有较强的抗肿瘤活性，剂量分别为0.1、0.2、0.4 mg/kg，其抑制率分别达到37.0%、43.2%、53.1%，显示出良好的量效关系。F3-PE39KDEL 在靶向治疗肿瘤方面具有较好的应用前景。

Recombinant Vascular Endothelial Receptor F3 Peptide-PE39KDEL Protein can Inhibit Tumor Growth

The objective was to investigate the antitumor effect of F3-PE39KDEL in vitro and in vivo. MTT method was employed to determine the inhibiting effect of F3-PE39KDEL on MCF-7, A549, SKOV3 and HepG2 cell lines. Its toxicity in mice was observed using the median lethal dose method. Its antitumor effect was determined based on the transplanted A549 cell line in nude mice. The results showed that when the culture times were 72 h and 120 h, the F3-PE39KDEL showed significant inhibitory effect on A549 and MCF-7 cell lines, with IC₅₀ values of 0.41 and 0.42 μg/mL, and 4.95 and 2.53 μg/mL, respectively. The toxicity test showed that the median lethal dose was 1.1782 mg/kg. The animals' spontaneous movement was decreased after administration, and animals died mainly within 1d after administration. All the animals including the dead and alive showed no abnormalities after sectional examination. The F3-PE39KDEL showed a potential antitumor effect in vivo. At the doses of 0.1, 0.2 and 0.4 mg/kg, its inhibitory rates were 37.0%, 43.2% and 53.1%, respectively, and the dose-activity relationship was also observed. These results suggest that the F3-PE39KDEL has good prospects in terms of targeted cancer therapy.