Clinical and Molecular Characteristics of Megakaryocytes in Myelodysplastic Syndrome.

Objective Myelodysplastic syndrome (MDS) is a malignant clonal disorder of hematopoietic stem cells which is characterized by morphologic dysplasia. However, the pathological characteristics of megakaryocytes (MKs) in MDS patients with gene mutation are not well established. Methods Bone marrow MK specimens from 104 patients with primary MDS were evaluated, and all patients were distributed into two groups according to gene mutation associated with functional MKs. The morphologic and cellular characteristics of MKs and platelets were recorded and compared. Results The more frequently mutated genes in MDS patients were TUBB1 (11.54%), VWF (8.65%), NBEAL2 (5.77%), and the most common point mutation was TUBB1 p.(R307H) and p.(Q43P). Patients with MK mutation showed a decrease in adenosine diphosphate-induced platelet aggregation, high proportion of CD34 + CD61 + MKs (10.00 vs. 4.00%, p = 0.012), and short overall survival (33.15 vs. 40.50 months, p = 0.013). Further, patients with a higher percent of CD34 + CD61 + MKs (≧20.00%) had lower platelet counts (36.00 × 10 9 /L vs. 88.50 × 10 9 /L, p = 0.015) and more profound emperipolesis ( p = 0.001). By analyzing RNA-sequencing of MKs, differentially expressed mRNA was involved in physiological processes including platelet function and platelet activation, especially for MDS patients with high percent of CD34 + CD61 + MKs. The high levels of expression of CD62P, CXCL10, and S100A9 mRNA, shown by RNA sequencing, were validated by PCR assay. Conclusion High proportion of CD34 + CD61 + MKs was a poor prognostic factor in MDS patients with MK mutation. CD62P, CXCL10, and S100A9 may be the potential targets to evaluate the molecular link between gene defects and platelet function.

SET Domain Containing 2 Deficiency in Myelodysplastic Syndrome.

Recent studies have shown that myelodysplastic syndrome's (MDS) progression to acute myeloid leukemia (AML) is associated with gene mutations. SET domain containing 2 (SETD2) variants were reported as a risk factor of poor prognosis in patients with AML. However, little is known about the potential contribution of the SETD2 gene in MDS. In this study, we investigated the roles of SETD2 gene mutations/variants on clinical features and prognosis in patients with MDS. A 43-gene panel was used for next-generation sequencing in 203 patients with primary MDS, and then the effects of SETD2 mutation on Wnt/ß-catenin signaling was investigated during the different stages of MDS. At a median follow up of 33 months, 65 (32.0%) deaths and 94 (46.3%) leukemic transformations were recorded. The most frequent mutations/variants included TET2, DNMT3A, and ASXL1 mutations/variants. 37 patients had SETD2 gene mutations/variants, and these patients exhibited a significantly increased frequency of TP53 mutations. Multivariate survival analyses indicated that SETD2 mutations/variants were closely associated with overall survival (OS), and they were identified as risk factors for progression-free survival (PFS), especially with low expression of SETD2 gene. Further, we found that SETD2 loss could promote MDS progression via upregulation DVL3 mRNA level in BM cells and it could also cause genomic instability. Secondary mutations, such as TP53 and FLT3 mutations, were acquired at the time of progression to AML. In conclusion, we showed that SETD2 deficiency was associated with poor outcomes in patients with MDS. Moreover, SETD2 deficiency may upregulate DVL3 expression and modulate genomic stability that caused AML transformation.

[Effect of immunoglobulin heavy/light chain detection on the minimal residual disease monitoring in IgG multiple myeloma patients].

OBJECTIVE: To evaluate the specificity and sensitivity of immunoglobulin heavy/light chain (HLC) and serum free light chain (FLC) level in minimal residual disease monitoring of IgG type multiple myeloma (MM) patients during complete remission (CR). METHODS: Immunoglobulin HLC was assessed in 20 IgG myeloma patients by immune turbidimetry using SPAplus Analyzer. The serum level of HLC and FLC was detected at same time. Combine with those obtained by serum protein electrophoresis (SPE) and immune fixation electrophoresis (IFE), the specificity and sensitivity of HLC in detection of serum immunoglobulin were analyzed. Combined with the clinical efficacy, kappa/lambda ratios of HLC (rHLC) and FLC (rFLC) were compared between the patients and normal controls. RESULTS: Among 20 patients, there were 10 male and 10 female, the median age was 56 years (35-70). There were 6 patients with abnormal rHLC but normal rFLC; 3 patients with abnormal rFLC but normal HLC; and 11 patients with both normal rHLC and rFLC. During the mean follow-up time of 18 months, 4 of the6 patients with abnormal rHLC accepted intervention therapies, 1 case relapsed in 9 months,the other 2 untreated patients relapsed in 3 months. Among the 3 cases with abnormal rFLC, 2 patients are still in remission after intervention therapies,the other untreated patient relapsed in 1.5 months. Among the 11 untreated patients with both normal rHLC and rFLC, 3 relapsed with the disease free survival time of 3.5 months, 5.0 months and 5.5 months respectively. CONCLUSION: The combined detection of HLC and FLC is helpful to assess the curative efficacy and the accuracy of minimal residual disease monitoring, and more effectively evaluate the prognosis of MM patients. Abnormal rHLC and rFLC are correlated with poor prognosis, while early intervention therapies can help to improve disease free survival.

Abnormal methylation of the sex-determining region Y-box 17 (SOX17) promoter predicts poor prognosis in myelodysplastic syndrome.

BACKGROUND: The sex-determining region Y-box 17 (SOX17) is a member of the high mobility group (HMG) transcription factor family, which plays critical roles in the regulation of development and stem/precursor cell function. Recent evidence demonstrated that SOX17 acts as a tumor-suppressor gene, at least partly though repression of Wnt pathway activity. METHODS: Here we report that SOX17 methylation was detected in THP-1 and SKM-I cell lines and SOX17 mRNA levels was up-regulated by 5-aza-dC. To clarify the role of SOXI7 in MDS, methylation-specific PCR (MSP) was employed to examine the methylation status of SOX17 in 164 adult de novo MDS patients and 6 normal samples. RESULTS: We found that SOX17 methylation was presented in 58.5% (n = 96) of these patients and none of the normal samples. Methylation was correlated significantly with World Health Organization (WHO) subtypes and international prognostic scoring system (IPSS) risk group. Patients with advanced stages of WHO subtypes (69.6% vs. 44.4%, p = 0.001) and higher risk IPSS subgroups (69.8% vs. 48.8%, p = 0.010) exhibited a significantly higher frequency of SOX17 methylation. Though multivariate analysis indicated that SOX17 methylation status was not the independent factor that impacted overall survival (OS) (HR = 0.097), there were significant differences in marrow blast levels and the IPSS risk subgroups between patients with and without SOX17 methylation. CONCLUSIONS: These findings suggest that the hypermethylation of SOX17 promoter may be one of the early events in the development of MDS and predicts poor prognosis.