Novel mutations in the inhibitory adaptor protein LNK drive JAK-STAT signaling in patients with myeloproliferative neoplasms

Blood - Tập 116 - Trang 988-992 - 2010
Stephen T. Oh1,2, Erin F. Simonds2, Carol Jones3, Matthew B. Hale2, Yury Goltsev2, Kenneth D. Gibbs2, Jason D. Merker3, James L. Zehnder1,3, Garry P. Nolan2, Jason Gotlib1
1Division of Hematology, Department of Medicine, Stanford University School of Medicine, CA
2Department of Microbiology & Immunology, and Stanford University School of Medicine, CA
3Department of Pathology, Stanford University School of Medicine, CA.

Tóm tắt

AbstractDysregulated Janus kinase–signal transducer and activator of transcription (JAK-STAT) signaling due to activation of tyrosine kinases is a common feature of myeloid malignancies. Here we report the first human disease-related mutations in the adaptor protein LNK, a negative regulator of JAK-STAT signaling, in 2 patients with JAK2 V617F–negative myeloproliferative neoplasms (MPNs). One patient exhibited a 5 base-pair deletion and missense mutation leading to a premature stop codon and loss of the pleckstrin homology (PH) and Src homology 2 (SH2) domains. A second patient had a missense mutation (E208Q) in the PH domain. BaF3-MPL cells transduced with these LNK mutants displayed augmented and sustained thrombopoietin-dependent growth and signaling. Primary samples from MPN patients bearing LNK mutations exhibited aberrant JAK-STAT activation, and cytokine-responsive CD34+ early progenitors were abnormally abundant in both patients. These findings indicate that JAK-STAT activation due to loss of LNK negative feedback regulation is a novel mechanism of MPN pathogenesis.

Tài liệu tham khảo

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