[The Expression of WTAP Gene in Acute Myeloid Leukemia and Its Clinical Significance].

OBJECTIVE: To investigate the expression of WTAP gene in acute myeloid leukemia (AML) and its clinical significance. METHODS: 74 acute myeloid leukemia patients with non-M3 type and 19 normal donors were selected, and real-time quantitative polymerase chain reaction was used to detect the mRNA expression level of WTAP gene in their bone marrow cells. The relationship between the mRNA expression level of WTAP gene and the clinical characteristics was analyzed. RESULTS: The relative mRNA expression of WTAP gene in the non-M3 AML group was significantly higher than that in the healthy control group, and the difference showed statistically significant (P<0.01). There showed no statistically significant difference in WTAP gene expression among each subtypes (all P>0.05) according to the classification of FAB. The mRNA expression level of WTAP gene in FLT3-ITD mutated AML patients was higher than that in FLT3-ITD unmutated group (P=0.016), and the mRNA expression level of WTAP gene in AML patients with CEBPα mutation was lower than that in CEBPα unmutated group (P=0.016). The expression level of WTAP mRNA was positively correlated with WT1 expression (r=0.6866, P<0.01). There was no relationship between WTAP mRNA expression level and other clinical parameters, such as age, gender, white blood cell count, hemoglobin level, platelet count, bone marrow original proportion of immature cells, chromosome karyotype, and NPM1, DNMT3A, ASXL1, NRAS, TET2 genes mutation status (P>0.05). The expression level of WTAP mRNA showed no obvious effect on the complete remission of patients after first treatment. The different expression level of WTAP gene at initial diagnosis showed also no effect on the overall survival time of patients. CONCLUSION: The expression level of WTAP gene is increasing in new diagnosed non-M3 acute myeloid leukemia. There is a positive correlation between the expression level of WTAP gene and the expression level of WT1 fusion gene. WTAP mRNA always shows higher expression in patients with FLT3-ITD mutation than that in patients without FLT3-ITD mutation, and shows lower expression in patients with CEBPα mutation than that in unmutated group.

Allogeneic haematopoietic stem cell transplantation improves outcome of adults with relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia entering remission following CD19 chimeric antigen receptor T cells.

Relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (r/r Ph+ ALL) has an extremely poor prognosis. Chimeric antigen receptor T-cell (CART) therapy has acquired unprecedented efficacy in B-cell malignancies, but its role in the long-term survival of r/r Ph+ ALL patients is unclear. We analyzed the effect of CART on 56 adults with r/r Ph+ ALL who accepted split doses of humanized CD19-targeted CART after lymphodepleting chemotherapy. 51/56 (91.1%) achieved complete remission (CR) or CR with inadequate count recovery (CRi), including 38 patients with negative minimal residual disease (MRD) tested by bone marrow BCR-ABL1 copies. Subsequently, 30/51 CR/CRi patients accepted consolidative allogeneic haematopoietic stem cell transplantation (alloHSCT). Their outcomes were compared with those of 21/51 contemporaneous patients without alloHSCT. The 2-year overall survival (OS) and leukemia-free survival (LFS) of CR/CRi patients with alloHSCT were significantly superior to those without alloHSCT (58.9%, CI 49.8-68.0% vs. 22.7%, CI 12.7-32.7%, p = 0.005; 53.2%, CI 43.6-62.8% vs. 18.8%, CI 9.2-28.4%, p = 0.000, respectively). Multivariate analysis revealed that alloHSCT and MRD-negative post-CART were the independent prognostic factors for OS and LFS. CART therapy is highly effective for r/r Ph+ ALL patients, and consolidative alloHSCT could prolong their OS and LFS.

Increased prostacyclin levels inhibit the aggregation and activation of platelets via the PI3K-AKT pathway in prolonged isolated thrombocytopenia after allogeneic hematopoietic stem cell transplantation.

OBJECTIVES: The aim of this study was to investigate the role of prostacyclin (PGI2) in prolonged isolated thrombocytopenia (PT) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) and the effect of PGI2 on the activation and aggregation of platelets in PT. METHODS: We enrolled 37 patients with PT and 36 controls following allo-HSCT in this study. Platelet aggregation and activation and PGI2 levels were measured. Endothelial progenitor cells (EPCs) from either PT or control patients were cultured ex vivo with serum from either PT or control patients. PGI2 secretions were then measured. PGI2 was added to the platelets ex vivo, and platelet aggregation and activation and PI3K/Akt phosphorylation were analyzed. RESULTS: A higher PGI2 level was observed in the PT patients. The activation and aggregation of platelets were significantly lower in the PT patients. EPCs from PT patients cultured in PT serum secreted higher levels of PGI2, and PGI2 inhibited platelet activation and aggregation in a concentration-dependent manner ex vivo. PI3K/Akt phosphorylation of platelets was regulated by PGI2 after allo-HSCT. Disease status, serum PGI2 level and platelet aggregation were independent risk factors in patients with PT after allo-HSCT. CONCLUSIONS: Higher PGI2 levels and lower platelet activation and aggregation occurred simultaneously in PT patients. PGI2 inhibited platelet activation and aggregation, probably by regulating the phosphorylation of PI3K/Akt.

IL-35 inhibits acute graft-versus-host disease in a mouse model.

Acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our previous study found that the novel anti-inflammatory cytokine IL-35 could suppress aGVHD in patients after allo-HSCT. In this study, we used C57BL/6 (B6, H-2b) mice as donors and (B6×DBA/2) F1 (BDF1, H-2b×d) mice as recipients to create a model of aGVHD and explore the relationship between IL-35 and aGVHD. The mice receiving IL-35 survived longer than did the control mice. We observed that treatment with IL-35 and RAPA could reduce the incidence of aGVHD. Additionally, this treatment inhibited intestinal and thymic epithelial cell apoptosis and liver infiltration by the donor T-cells, thereby ameliorating the enteropathy and liver injury caused by aGVHD. We found that IL-35 and RAPA also markedly suppressed TNF-α and IL-17A expression and enhanced IFN-γ expression in the intestine and liver. We measured Tregs in spleen and found that IL-35 and RAPA treatment expanded the number of Tregs in spleen. We found that the phosphorylation of STAT1 and STAT4 were inhibited in mice with aGVHD. In contrast, STAT1 and STAT4 were phosphorylated when the mice were treated with IL-35. IL-35 may have therapeutic potential in the treatment of aGVHD after allo-HSCT.

[Identification of a missense mutation in SEDL gene from a Chinese family with X-linked spondyloepiphyseal dysplasia tarda].

OBJECTIVE: To identify the SEDL gene mutation in a Chinese family with X-linked spondyloepiphyseal dysplasia tarda (SEDL) and to establish a genotyping assay for rapid diagnosis of this X-linked recessive disorder. METHODS: Clinical diagnoses were made based on physical examination, radiological examination and pedigree analysis for this family. Four primer pairs flanking the SEDL exons 3-6 including their exon/intron boundaries were designed. A rapid genotyping assay based on denaturing high performance liquid chromatography (DHPLC) was established to screen the point mutations of the SEDL gene. Genomic DNA was extracted by standard methods from 18 members in the three generations of the pedigree and subjected to PCR-denaturing high performance liquid chromatography (PCR-DHPLC) assay followed by direct DNA sequencing. RESULTS: A c.218C>T mutation in exon 4 of the SEDL gene, which resulted in a substitution of serine 218 with leucine, was identified in this family. Among the 18 members, 3 patients, 5 obligate female carriers and 2 unmarried young females were found to have the missense mutation, and other 8 healthy individuals were not detected to carry the mutation, in which genotype-phenotype correlations were well established in each member investigated in this family. CONCLUSION: A c.218C>T missense mutation in the SEDL gene was firstly reported in Chinese population and the results of this study expand the spectrum of SEDL mutations. The PCR-DHPLC assay is a useful tool to rapidly detect the SEDL mutation in clinical and prenatal diagnosis.