Vitali Roberta, Mancini Camillo, Cesi Vincenzo, Tanno Barbara, Piscitelli Marta, Mancuso Mariateresa, Sesti Fabiola, Pasquali Emanuela, Calabretta Bruno, Dominici Carlo, Raschellà Giuseppe
Section of Toxicology and Biomedical Sciences, Research Center Casaccia, ENEA, Rome, Italy.
Int J Cancer. 2009 Dec 1;125(11):2547-55. doi: 10.1002/ijc.24606.
Stage 4 neuroblastoma (NB) is a devastating childhood cancer whose poor outcome has remained essentially unchanged in the last 20 years. Receptor tyrosine kinases have important roles in the control of proliferation, differentiation and apoptosis of NB cells. Thus, we tested the activity of second-generation tyrosine kinase inhibitor Dasatinib in human NB cell lines in vitro and in an orthotopic mouse model. Dasatinib inhibited cell viability with an IC(50) in the submicromolar range in 7 of 10 tested cell lines. In sensitive cells, Dasatinib reduced anchorage-independent growth and, in some instances, induced senescence and apoptosis. In HTLA-230 cells, Dasatinib treatment caused down-regulation of c-Kit and c-Src phosphorylation in conjunction with strong inhibition of Erk1/2 and Akt activity. To test the efficacy of Dasatinib in vivo, HTLA-230 and SY5Y cells were orthotopically injected in the adrenal gland of nude mice and drug treatments carried out until day 40. In mice injected with HTLA-230 cells, tumour growth was significantly inhibited at the dose of 30 mg/(kg day) when treatment was started 7 days after injection. In animals injected with SY5Y cells that were exquisitely sensitive in vitro (IC(50)= 92 nM), the antitumour effect of Dasatinib was observed at the dose of 60 mg/(kg day) but only when treatment was started 1 day after injection. However, the anti-tumour effect of Dasatinib in vivo was partial in both orthotopic models, emphasizing the importance of testing candidate new drugs in animal environments closely mimicking the human tumour.
4期神经母细胞瘤（NB）是一种毁灭性的儿童癌症，在过去20年里其较差的预后基本没有改变。受体酪氨酸激酶在NB细胞的增殖、分化和凋亡控制中发挥重要作用。因此，我们在体外人NB细胞系和原位小鼠模型中测试了第二代酪氨酸激酶抑制剂达沙替尼的活性。达沙替尼在10个测试细胞系中的7个中以亚微摩尔范围内的IC（50）抑制细胞活力。在敏感细胞中，达沙替尼减少了不依赖贴壁的生长，在某些情况下，还诱导了衰老和凋亡。在HTLA-230细胞中，达沙替尼处理导致c-Kit和c-Src磷酸化下调，同时强烈抑制Erk1/2和Akt活性。为了测试达沙替尼在体内的疗效，将HTLA-230和SY5Y细胞原位注射到裸鼠的肾上腺中，并进行药物治疗直至第40天。在注射HTLA-230细胞的小鼠中，当在注射后7天开始治疗时，30 mg/（kg·天）的剂量可显著抑制肿瘤生长。在注射对体外极其敏感（IC（50）= 92 nM）的SY5Y细胞的动物中，在60 mg/（kg·天）的剂量下观察到达沙替尼的抗肿瘤作用，但仅在注射后1天开始治疗时才观察到。然而，达沙替尼在两种原位模型中的体内抗肿瘤作用都是部分性的，这强调了在紧密模拟人类肿瘤的动物环境中测试候选新药的重要性。
