In vivo antitumor activity of DNA-specific ADP-ribosyltransferase, pierisin-1

粉蝶素-1，一种在菜粉蝶中发现的98-kDa蛋白，对癌细胞具有细胞毒性。为了检查该蛋白质是否具有体内抗癌活性，分析了对小鼠的急性毒性和对移植肿瘤的抑制作用。经<50>腹腔注射给BALB/c小鼠的LD_（50）约为5 μg/kg体重。在第一天接种1 × 10^7个HeLa细胞的BALB/c nu/nu雌性6周龄裸鼠在第二天接受3 μg/kg剂量的粉蝶菌素-1的腹膜内注射。此后，在第80天处死动物。在所有10只未经粉蝶菌素-1处理的小鼠中均形成肿瘤，平均肿瘤重量为1.16 g/小鼠。在用粉蝶素-1处理的小鼠中，平均肿瘤重量为每只小鼠0.56 g，并且其值显著更低，并且在十只测试小鼠中的三只中未发现肿瘤。我们的研究结果表明，pierisin-1在体内具有抗肿瘤活性。接下来，我们从1，340个紫粉蝶中纯化了47.6 mg粉蝶素-1。酶促特性表明，N-末端多肽和胰蛋白酶处理的pierisin-1的最大营业额分别为每秒55和25。在某些条件下，相关的C-末端片段对N-末端酶结构域的抑制是明显的。长期反应表明，一个单一分子的粉蝶素-1能够产生超过10^6个ADP-核糖基化DNA加合物，这可能导致哺乳动物细胞死亡。

Pierisin-1, a 98-kDa protein found in cabbage butterfly, exhibits cytotoxicity to cancer cells. To examine whether this protein has anti-cancer activity in viva, acute toxicity to mice and suppression effects to transplanted tumors were analyzed. The LD_<50> value for pierisin-1 was around 5 μg/kg body weight on intraperitoneal injection into BALB/c mice. BALB/c nu/nu female 6-week-old nude mice inoculated 1 x 10^7 HeLa cells on the first day were subjected for intraperitoneal injection of pierisin-1 at a dose of 3 μg/kg on the next day. Thereafter, animals were killed at day 80. Tumors were formed in all ten mice treated without pierisin-1 and the mean tumor weight was 1.16 g per mouse. In mice treated with pierisin-1, the mean tumor weight was 0.56 g per mouse, and its value was significantly lower and no tumors were found in three of ten mice tested. Our results indicate that pierisin-1 has antitumor activity in viva. Next, we purified 47.6 mg pierisin-1 from 1,340 pupae of Pieris rapae. Enzymatic characterization demonstrated that the maximum turnover number of the N-terminal polypeptide and trypsin-treated pierisin-1 were 55 and 25 per second, respectively. Inhibition of the N-terminal enzyme domain by the associated C-terminal fragment was evident under certain conditions. Long-term reactions indicated that a single molecule of pierisin-1 has the capacity to generate more than 10^6 ADP-ribosylated DNA adducts, which could cause the death of a mammalian cell.