KINOME EXPRESSION PROFILING FOR RISK STRATIFICATION OF MYELODYSPLASTIC SYNDROMES

Introduction: Myelodysplastic syndrome (MDS) is a heterogeneous constellation of myeloid neoplasms originating from the clonal proliferation of aberrant hematopoietic stem cells (HSC). The human kinome, which comprises over five hundred kinases, plays a critical role in regulating numerous cellular functions. Although the dysregulation of kinases has been observed in various human cancers, the characterization and clinical implications of kinase expressions in MDS have not been investigated before. Methods: Overall, 341 patients diagnosed with primary MDS according to the 2016 WHO classification, who had adequate cryopreserved diagnostic unsorted bone marrow (BM) samples for DNA and RNA sequencing, were recruited. The normalized gene expressions of a total of 517 kinase gene were studied. We first identified those kinases whose expressions were higher in MDS patients than in healthy controls, and then used LASSO-regularized Cox proportional hazards regression to identify prognostically significant kinases to construct the KInase Stratification Score (KISS). Results: We discovered that the expression levels of seven kinases (PTK7, KIT, MAST4, NTRK1, PAK6, CAMK1D, PRKCZ) could predict patient outcome, and we used these kinases to construct the KISS; we further validated its prognostic significance in two external MDS cohorts. A higher KISS was associated with older age, higher BM blast percentage, higher IPSS-R risk, complex karyotype, and mutations in several adverse-risk genes in MDS. In the multivariate analysis, a higher KISS was proved to be an independent unfavorable risk factor. Conclusions: Altogether, our findings suggest that KISS holds the potential to improve the current prognostic scheme of MDS, and inform novel therapeutic opportunities.