INSERM, Unité Mixte de Recherche 892, Nantes, France; Université de Nantes, Nantes, France; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 6299, Nantes, France; Service d'Hématologie, Centre Hospitalo-Universitaire Nantes, Nantes, France;
INSERM, Unité Mixte de Recherche 892, Nantes, France; Université de Nantes, Nantes, France; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 6299, Nantes, France;
Blood. 2014 Sep 4;124(10):1626-36. doi: 10.1182/blood-2014-01-548800. Epub 2014 Jul 8.
The aim of this study was to assess the efficiency of p53 reactivation and induction of massive apoptosis (PRIMA-1(Met)) in inducing myeloma cell death, using 27 human myeloma cell lines (HMCLs) and 23 primary samples. Measuring the lethal dose (LD50) of HMCLs revealed that HMCLs displayed heterogeneous sensitivity, with an LD50 ranging from 4 μM to more than 200 μM. The sensitivity of HMCLs did not correlate with myeloma genomic heterogeneity or TP53 status, and PRIMA-1(Met) did not induce or increase expression of the p53 target genes CDKN1A or TNFRSF10B/DR5. However, PRIMA-1(Met) increased expression of NOXA in a p53-independent manner, and NOXA silencing decreased PRIMA1(Met)-induced cell death. PRIMA-1(Met) depleted glutathione (GSH) content and induced reactive oxygen species production. The expression of GSH synthetase correlated with PRIMA-1(Met) LD50 values, and we showed that a GSH decrease mediated by GSH synthetase silencing or by and L-buthionine sulphoximine, an irreversible inhibitor of γ-glutamylcysteine synthetase, increased PRIMA-1(Met)-induced cell death and overcame PRIMA-1(Met) resistance. PRIMA-1(Met) (10 μM) induced cell death in 65% of primary cells independent of the presence of del17p; did not increase DR5 expression, arguing against an activation of p53 pathway; and synergized with L-buthionine sulphoximine in all samples. Finally, we showed in mouse TP53(neg) JJN3-xenograft model that PRIMA-1(Met) inhibited myeloma growth and synergized with L-buthionine sulphoximine in vivo.
本研究旨在评估 p53 再激活和诱导大量细胞凋亡（PRIMA-1(Met)）在诱导骨髓瘤细胞死亡方面的效率，使用了 27 个人骨髓瘤细胞系（HMCL）和 23 个原发性样本。测量 HMCL 的致死剂量（LD50）表明，HMCL 表现出异质性的敏感性，LD50 范围从 4 μM 到 200 μM 以上。HMCL 的敏感性与骨髓瘤基因组异质性或 TP53 状态无关，PRIMA-1(Met) 不会诱导或增加 p53 靶基因 CDKN1A 或 TNFRSF10B/DR5 的表达。然而，PRIMA-1(Met) 以 p53 非依赖性方式增加了 NOXA 的表达，而 NOXA 沉默则降低了 PRIMA1(Met)诱导的细胞死亡。PRIMA-1(Met) 耗竭了谷胱甘肽 (GSH) 含量并诱导了活性氧的产生。GSH 合成酶的表达与 PRIMA-1(Met)LD50 值相关，我们表明，通过 GSH 合成酶沉默或不可逆的γ-谷氨酰半胱氨酸合成酶抑制剂 L-丁硫氨酸亚砜胺介导的 GSH 减少，增加了 PRIMA-1(Met)诱导的细胞死亡并克服了 PRIMA-1(Met) 耐药性。PRIMA-1(Met)（10 μM）在 65%的原发性细胞中诱导细胞死亡，与 del17p 的存在无关；没有增加 DR5 的表达，这表明 p53 途径没有被激活；并且在所有样本中与 L-丁硫氨酸亚砜胺协同作用。最后，我们在 TP53(neg) JJN3-异种移植模型小鼠中表明，PRIMA-1(Met) 抑制骨髓瘤生长并与 L-丁硫氨酸亚砜胺在体内协同作用。
