iPSC modeling of stage-specific leukemogenesis reveals BAALC as a key oncogene in severe congenital neutropenia.

Severe congenital neutropenia (CN) is a pre-leukemic bone marrow failure syndrome that can evolve to acute myeloid leukemia (AML). Mutations in CSF3R and RUNX1 are frequently observed in CN patients, although how they drive the transition from CN to AML (CN/AML) is unclear. Here we establish a model of stepwise leukemogenesis in CN/AML using CRISPR-Cas9 gene editing of CN patient-derived iPSCs. We identified BAALC upregulation and resultant phosphorylation of MK2a as a key leukemogenic event. BAALC deletion or treatment with CMPD1, a selective inhibitor of MK2a phosphorylation, blocked proliferation and induced differentiation of primary CN/AML blasts and CN/AML iPSC-derived hematopoietic stem and progenitor cells (HSPCs) without affecting healthy donor or CN iPSC-derived HSPCs. Beyond detailing a useful method for future investigation of stepwise leukemogenesis, this study suggests that targeting BAALC and/or MK2a phosphorylation may prevent leukemogenic transformation or eliminate AML blasts in CN/AML and RUNX1 mutant BAALC(hi) de novo AML.

Prognostic effect of RUNX1 mutations in myelodysplastic syndromes: a meta-analysis.

OBJECTIVES: RUNX1 mutations have been widely found in patients with myelodysplastic syndrome (MDS). Majority of reports revealed that RUNX1 mutations are associated with a poor prognosis. However, discrepancies still remain. The results of univariate analysis were not confirmed in multivariate analysis in some cases. Therefore, we performed a meta-analysis to assess the prognostic effect of RUNX1 mutations in MDS. METHODS: We extracted data from qualified studies that were searched from PubMed, Embase and the Cochrane Library. Hazard ratios (HRs) and their 95% confidence intervals (CIs) for the overall survival (OS) and leukemia free survival (LFS) were pooled from the multivariate Cox proportional hazard models. RESULTS: Sixteen studies containing 5422 patients were included in this meta-analysis. There were 617 patients with mutated RUNX1 and 4805 patients with wide type RUNX1. The total HR for OS was 1.43 (95% CI = 1.21-1.70, P < 0.0001) and the counterpart of LFS was 1.88 (95% CI = 1.42-2.51, P < 0.0001). DISCUSSION AND CONCLUSION: These results suggest that the RUNX1 mutations are associated with unfavorable outcomes and shorter survival in patients with MDS. Furthermore, poor prognosis of patients might be alleviated by stem cell transplantation. Patients bearing these mutations should be prioritized for aggressive therapy.

Cooperating, congenital neutropenia-associated Csf3r and Runx1 mutations activate pro-inflammatory signaling and inhibit myeloid differentiation of mouse HSPCs.

Patients with the pre-leukemia bone marrow failure syndrome called severe congenital neutropenia (CN) have an approximately 15% risk of developing acute myeloid leukemia (AML; called here CN/AML). Most CN/AML patients co-acquire CSF3R and RUNX1 mutations, which play cooperative roles in the development of AML. To establish an in vitro model of leukemogenesis, we utilized bone marrow lin- cells from transgenic C57BL/6-d715 Csf3r mice expressing a CN patient-mimicking truncated CSF3R mutation. We transduced these cells with vectors encoding RUNX1 wild type (WT) or RUNX1 mutant proteins carrying the R139G or R174L mutations. Cells transduced with these RUNX1 mutants showed diminished in vitro myeloid differentiation and elevated replating capacity, compared with those expressing WT RUNX1. mRNA expression analysis showed that cells transduced with the RUNX1 mutants exhibited hyperactivation of inflammatory signaling and innate immunity pathways, including IL-6, TLR, NF-kappaB, IFN, and TREM1 signaling. These data suggest that the expression of mutated RUNX1 in a CSF3R-mutated background may activate the pro-inflammatory cell state and inhibit myeloid differentiation.

The Clinical, Molecular, and Mechanistic Basis of RUNX1 Mutations Identified in Hematological Malignancies.

RUNX1 plays an important role in the regulation of normal hematopoiesis. RUNX1 mutations are frequently found and have been intensively studied in hematological malignancies. Germline mutations in RUNX1 cause familial platelet disorder with predisposition to acute myeloid leukemia (FPD/AML). Somatic mutations of RUNX1 are observed in various types of hematological malignancies, such as AML, acute lymphoblastic leukemia (ALL), myelodysplastic syndromes (MDS), myeloproliferative neoplasm (MPN), chronic myelomonocytic leukemia (CMML), and congenital bone marrow failure (CBMF). Here, we systematically review the clinical and molecular characteristics of RUNX1 mutations, the mechanisms of pathogenesis caused by RUNX1 mutations, and potential therapeutic strategies to target RUNX1-mutated cases of hematological malignancies.

[Clinical features and curative effect analysis of patients with myeloid neoplasms and RUNX1 mutations].

Objective: To investigate the survival and prognostic factors of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for patients with myeloid neoplasms and RUNX1 mutations. Methods: From July 2014 to April 2018, the clinical data of forty-two AML/MDS patients with RUNX1 mutations in the First Affiliated Hospital of Soochow University were retrospectively analyzed. The clinical characteristic features and distribution of the mutations frequently observed with RUNX1 mutations were summarized, the prognosis of allo-HSCT for these patients was also analyzed. Results: Among 42 AML/MDS patients with RUNX1 mutations, 27 were male, 15 were female. The median age was 43.5 (16-68) years old. There are 31 patients in allo-HSCT group and 11 patients in chemotherapy group. RUNX1 mutations co-occurred with many other gene mutations, the most frequent mutations were FLT3 (26.2%, 11/42) . Interestingly, FLT3 mutations only occurred in AML patients compared with MDS patients (P=0.014) . ASXL1 (25%, 3/12) mutations were observed as the most frequent co-mutations in MDS patients. One-year overall survival (OS) , disease-free survival (DFS) of allo-HSCT and chemotherapy patients were (70.6±9.0) %, (61.0±9.4) % and (34.4±16.7) %, (22.4±15.3) %, respectively. When OS and DFS between allo-HSCT and chemotherapy patients were compared, significant differences (χ(2)=4.843, 4.320, P<0.05) were showed. In univariate analysis, transplant age >45 years was a negative effect for OS [HR=4.819 (95% CI 1.145-20.283) , P=0.032] and DFS [HR=5.945 (95% CI 1.715-20.604) , P=0.005]. Also, complex chromosome karyotype abnormality was a negative effect for OS [HR=5.572 (95%CI 1.104-28.113) , P=0.038]. Conclusion: Transplant age (>45 years) and complex chromosome karyotype abnormality were negative prognostic factors in allo-HSCT for myeloid neoplasms patients with RUNX1 mutations.

Clinical features and curative effect analysis of patients with myeloid neoplasms and RUNX1 mutations / 中华血液学杂志

Objective: To investigate the survival and prognostic factors of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for patients with myeloid neoplasms and RUNX1 mutations. Methods: From July 2014 to April 2018, the clinical data of forty-two AML/MDS patients with RUNX1 mutations in the First Affiliated Hospital of Soochow University were retrospectively analyzed. The clinical characteristic features and distribution of the mutations frequently observed with RUNX1 mutations were summarized, the prognosis of allo-HSCT for these patients was also analyzed. Results: Among 42 AML/MDS patients with RUNX1 mutations, 27 were male, 15 were female. The median age was 43.5 (16-68) years old. There are 31 patients in allo-HSCT group and 11 patients in chemotherapy group. RUNX1 mutations co-occurred with many other gene mutations, the most frequent mutations were FLT3 (26.2%, 11/42) . Interestingly, FLT3 mutations only occurred in AML patients compared with MDS patients (P=0.014) . ASXL1 (25%, 3/12) mutations were observed as the most frequent co-mutations in MDS patients. One-year overall survival (OS) , disease-free survival (DFS) of allo-HSCT and chemotherapy patients were (70.6±9.0) %, (61.0±9.4) % and (34.4±16.7) %, (22.4±15.3) %, respectively. When OS and DFS between allo-HSCT and chemotherapy patients were compared, significant differences (χ(2)=4.843, 4.320, P<0.05) were showed. In univariate analysis, transplant age >45 years was a negative effect for OS [HR=4.819 (95% CI 1.145-20.283) , P=0.032] and DFS [HR=5.945 (95% CI 1.715-20.604) , P=0.005]. Also, complex chromosome karyotype abnormality was a negative effect for OS [HR=5.572 (95%CI 1.104-28.113) , P=0.038]. Conclusion: Transplant age (>45 years) and complex chromosome karyotype abnormality were negative prognostic factors in allo-HSCT for myeloid neoplasms patients with RUNX1 mutations.

Clinical features and curative effect analysis of patients with myeloid neoplasms and RUNX1 mutations / 中华血液学杂志

Objective@#To investigate the survival and prognostic factors of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for patients with myeloid neoplasms and RUNX1 mutations.@*Methods@#From July 2014 to April 2018, the clinical data of forty-two AML/MDS patients with RUNX1 mutations in the First Affiliated Hospital of Soochow University were retrospectively analyzed. The clinical characteristic features and distribution of the mutations frequently observed with RUNX1 mutations were summarized, the prognosis of allo-HSCT for these patients was also analyzed.@*Results@#Among 42 AML/MDS patients with RUNX1 mutations, 27 were male, 15 were female. The median age was 43.5 (16-68) years old. There are 31 patients in allo-HSCT group and 11 patients in chemotherapy group. RUNX1 mutations co-occurred with many other gene mutations, the most frequent mutations were FLT3 (26.2%, 11/42) . Interestingly, FLT3 mutations only occurred in AML patients compared with MDS patients (P=0.014) . ASXL1 (25%, 3/12) mutations were observed as the most frequent co-mutations in MDS patients. One-year overall survival (OS) , disease-free survival (DFS) of allo-HSCT and chemotherapy patients were (70.6±9.0) %, (61.0±9.4) % and (34.4±16.7) %, (22.4±15.3) %, respectively. When OS and DFS between allo-HSCT and chemotherapy patients were compared, significant differences (χ2=4.843, 4.320, P<0.05) were showed. In univariate analysis, transplant age >45 years was a negative effect for OS [HR=4.819 (95% CI 1.145-20.283) , P=0.032] and DFS [HR=5.945 (95% CI 1.715-20.604) , P=0.005]. Also, complex chromosome karyotype abnormality was a negative effect for OS [HR=5.572 (95%CI 1.104-28.113) , P=0.038].@*Conclusion@#Transplant age (>45 years) and complex chromosome karyotype abnormality were negative prognostic factors in allo-HSCT for myeloid neoplasms patients with RUNX1 mutations.

A novel recurrent copy number loss region on 6q23.3 in MDS-related myeloid malignancy patients with stable survival conditions.

Metaphase cytogenetics (MC) karyotyping is a fundamental way to approach cytogenetic pathogenesis of MDS-related myeloid malignancies. However, in some patients, the results are normal while the patients often show discrepancies in survival conditions. To explain this question, we analyzed CytoScan™ HD array results of 20 MC-normal/failure patients who were followed up for three years. Exon sequencing was performed in genes RUNX1, TP53, ASXL1, and TET2. The array enabled the detection of additional aberrations in 16 (80%) patients. Eight patients were detected with cryptic copy number losses and six of them got aggressive disease conditions. RUNX1 mutations were sequenced in P110 and P114. Most importantly, two patients (P114 and P116) with copy number loss aberrations got stable survival conditions during follow-ups, and a novel recurrent copy number loss region harboring the proto-oncogene MYB was detected on chromosome 6q23.3 in both of them, which might benefit the survival of the patients.