NPM-ALK mediates phosphorylation of MSH2 at tyrosine 238, creating a functional deficiency in MSH2 and the loss of mismatch repair.
NPM-ALK mediates phosphorylation of MSH2 at tyrosine 238, creating a functional deficiency in MSH2 and the loss of mismatch repair.
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DOI：
10.1038/bcj.2015.35
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发表时间：
2015-05-15
影响因子：
12.8
通讯作者：
Lai R
中科院分区：
文献类型：
--
作者：
Bone KM;Wang P;Wu F;Wu C;Li L;Bacani JT;Andrew SE;Lai R
绝大多数间变性淋巴瘤激酶阳性间变性大细胞淋巴瘤（ALK+ALCL）肿瘤表达特征性致癌融合蛋白NPM-ALK，其通过对各种底物发挥组成性酪氨酸激酶活性介导肿瘤发生。我们最近发现MSH 2是DNA错配修复（MMR）的核心蛋白，是NPM-ALK的新型结合伴侣和磷酸化底物。在这里，使用液相色谱-质谱法，我们报告的第一次，MSH 2是磷酸化的NPM-ALK在一个特定的残基，酪氨酸238。使用NPM-ALK转染的GP 293细胞，我们证实MSH 2 Y238 F突变体没有被酪氨酸磷酸化。此外，MSH 2 Y238 F转染到这些细胞中显著降低了内源性MSH 2的酪氨酸磷酸化。重要的是，MSH 2 Y238 F的基因转染消除了NPM-ALK与内源性MSH 2的结合，重新建立了MSH 2：MSH 6的二聚化，并恢复了对DNA错配诱导药物的敏感性，表明MMR恢复。在两种ALK+ALCL细胞系Karpas 299和SUP-M2中观察到类似结果。此外，我们发现单独在ALK+ALCL细胞中强制表达MSH 2 Y238 F足以诱导自发性凋亡。总之，我们的研究结果已经确定NPM-ALK诱导的MSH 2 Y238磷酸化是抑制MMR的关键事件。我们的研究为致癌酪氨酸激酶破坏MMR的机制提供了新的见解。
The vast majority of anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK+ALCL) tumors express the characteristic oncogenic fusion protein NPM-ALK, which mediates tumorigenesis by exerting its constitutive tyrosine kinase activity on various substrates. We recently identified MSH2, a protein central to DNA mismatch repair (MMR), as a novel binding partner and phosphorylation substrate of NPM-ALK. Here, using liquid chromatography–mass spectrometry, we report for the first time that MSH2 is phosphorylated by NPM-ALK at a specific residue, tyrosine 238. Using GP293 cells transfected with NPM-ALK, we confirmed that the MSH2Y238F mutant is not tyrosine phosphorylated. Furthermore, transfection of MSH2Y238F into these cells substantially decreased the tyrosine phosphorylation of endogenous MSH2. Importantly, gene transfection of MSH2Y238F abrogated the binding of NPM-ALK with endogenous MSH2, re-established the dimerization of MSH2:MSH6 and restored the sensitivity to DNA mismatch-inducing drugs, indicative of MMR return. Parallel findings were observed in two ALK+ALCL cell lines, Karpas 299 and SUP-M2. In addition, we found that enforced expression of MSH2Y238F into ALK+ALCL cells alone was sufficient to induce spontaneous apoptosis. In conclusion, our findings have identified NPM-ALK-induced phosphorylation of MSH2 at Y238 as a crucial event in suppressing MMR. Our studies have provided novel insights into the mechanism by which oncogenic tyrosine kinases disrupt MMR.
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DOI：
10.1093/jnci/89.20.1537
发表时间：
1997-10-15
期刊：
JOURNAL OF THE NATIONAL CANCER INSTITUTE
影响因子：
--
作者：
delasAlas, MM;Aebi, S;Los, G
通讯作者：
Los, G
影响因子：
16
作者：
Hickman, MJ;Samson, LD
通讯作者：
Samson, LD
影响因子：
11.5
作者：
Kinsella, Timothy J.
通讯作者：
Kinsella, Timothy J.
影响因子：
3.5
作者：
Hernandez-Pigeon, H;Laurent, G;Lautier, D
通讯作者：
Lautier, D
影响因子：
5.6
作者：
Hernandez-Pigeon, H;Quillet-Mary, A;Lautier, D
通讯作者：
Lautier, D