Neuroblastoma (NB) is a highly malignant solid tumor in children. The cysteine endopeptidase legumain is expressed in adult solid tumors, but its expression in NB has not been examined. In this study, we assayed legumain expression in two NB cell lines and in microarrays of tumor tissues collected from 46 children with undifferentiated NB, differentiated NB, and ganglioneuroblastoma. Correlation analyses showed that legumain was expressed in all NB cell lines tested and that expression correlated with the degree of tumor differentiation. The efficacy, specificity, and toxicity of EMC-AANL-DOX, a novel doxorubicin-based legumain-activated prodrug, were then evaluated in mouse model of NB. Compared with DOX, EMC-AANL-DOX showed greater inhibition of tumor growth and a lower toxicity at high doses. Neither leukocyte or platelet counts nor renal function or cardiac anatomy differed significantly between the EMC-AANL-DOX and control groups (p > .05), suggesting that the prodrug caused minimal bone marrow depression and did not induce renal or cardiac damage. The good specificity and efficacy of EMC-AANL-DOX and low toxicity recommend its use in the treatment of NB. Correlation analyses of NB differentiation and legumain expression may reveal a novel anti-tumor-related functions of the drug and a new strategy for the treatment of pediatric solid tumors.

Legumain correlated with neuroblastoma differentiation by detection of clinic tumors. EMC-AANL-DOX activated by legumain presented better efficacy and lower toxicity in tumor-bearing models of neuroblastoma.

神经母细胞瘤（NB）是儿童的高度恶性实体瘤。半胱氨酸内肽酶legumain在成人实体瘤中表达，但尚未在NB中检查其表达。在这项研究中，我们测定了豆科菌素在两种NB细胞系中的表达以及在从46例未分化NB，分化的NB和神经节神经母细胞瘤患儿收集的肿瘤组织的微阵列中的表达。相关分析表明，豆荚菌素在所有测试的NB细胞系中均有表达，且该表达与肿瘤分化程度相关。然后，在NB小鼠模型中评估了EMC-AANL-DOX（一种新的基于阿霉素的豆腐素激活的前药）的功效，特异性和毒性。与DOX相比，EMC-AANL-DOX在高剂量时显示出对肿瘤生长的更大抑制作用和更低的毒性。p  > .05），表明该前药可引起最小的骨髓抑制，并且不会引起肾脏或心脏损害。EMC-AANL-DOX的良好特异性和功效以及低毒性建议将其用于NB的治疗。NB分化和豆荚菌素表达的相关分析可能揭示该药物的新型抗肿瘤相关功能和治疗小儿实体瘤的新策略。

豆蔻因通过检测临床肿瘤与神经母细胞瘤分化相关。在神经母细胞瘤的荷瘤模型中，legumain激活的EMC-AANL-DOX表现出更好的功效和更低的毒性。