Two Kinds of HLA-mismatched Allogeneic Hematopoictic Stem Cell Transplantation for Treatment of Hematologic Malignancies / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the safety and effectiveness of HLA-mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT) combined with related haploidentical bone marrow infusion for treatment of hematologic malignancies and to explore the mathod for reduction of aGVHD incidence and clinical significance.</p><p><b>METHODS</b>A total of 30 patients with hematologic malignancies (8 cases of AML, 17 AML, 2 MDS and 3 Mix-AL) received related haploidentical and unrelated HLA-mismatched allo-HSCT combined with related haploidentical bone marrow infusion. Among them 20 cases received related haploidentical transplantation of the first donor, 10 cases received unrelated HLA-mismatched treaplantation. The new conditioning regimen for the patients underwent allo-HSCT consisted of fludarabine, busulfan, Me-CCNU and cyclophosphamide. The drugs for GVHD prophylaxis included cyclosporine A and methotrexate, while mycophenolate mofetil and rabbit anti-T-lymphocyte globulin (ATG) were used.</p><p><b>RESULTS</b>All the patients achieved full engraftment. The median time for neutrophils to reach over 0.5 × 10(9)/L was 14 days (8-26 days), while the median time for platelets to reach over 20 × 10(9)/L was 11.5days (10-24 days). The incidence of I-II grade of aGVHD at 100 d was 22.28% (95% CI 9.9%-34.7%), the incidences of II-IV and III-IV grade of aGVHD were 22.7% (95% CI, 10%-35.4%) and 12.7% (95% CI 6.9%-15.5%) respectively. The incidences of I-II and III-IV cGVHD were 13.3% (95% CI, 1.4%- 26.8%) and 3.3 % (95% CI, 0%-12.2%), one case (3.3%) was in extensive cGVHD. DFS and OS of 2 years were 81.1% (95% CI, 66.0%-96.2%) and 68.2% (95% CI 51.0%-85.4%).</p><p><b>CONCLUSION</b>These data suggest that the incidence of grade II-IV grade of aGVHD in recipients of 2 partially HLA-matched units was lower, co-infusion of haplo-BM and partially matched units in allogeneic transplantation is safe and effective for reducing the incidence of aGVHD and improving the survival in DFS.</p>

Correlations of jak2v617f mutation with clinical and laboratory findings in primary thrombocythemia patients / 中国实验血液学杂志

To evaluate the frequency of jak2v617f mutation and analyze its correlation with clinical features of primary thrombocythemia (PT) patients, the mutation was detected by allele specific polymerase chain reaction (AS-PCR), the clinical and laboratory data in 66 PT patients with and without jak2v617f mutation were compared and clinical features of these PT patients were retrospectively analyzed. The results showed that among 66 patients, 27 patients (41%) had the mutation. The patients carrying the mutation displayed higher bone marrow erythropoiesis (26.9%+/-9.4% vs 16.3%+/-8.7%, p<0.05), higher ratio of granulopoiesis/erythropoiesis (2.9+/-1.8 vs 5.2+/-2.9, p<0.05) and higher incidence of microvascular disturbances (29.6% vs 5.1%, p<0.05). However, the age, gender, leukocyte and platelet counts, hemoglobin level, bone granulopoiesis, splenomegaly, history of thrombosis and hemorrhage had no difference between patients with and without the mutation. It is concluded that the frequency of jak2v617f mutation in primary thrombocythemia patients is 41%. The presence of the jak2v617f mutation is associated with a higher bone marrow erythropoiesis in primary thrombocythemia patients at diagnosis.

JAK2V617F mutation in patients with idiopathic myelofibrosis / 中国实验血液学杂志

To investigate JAK2V617F mutation and its clinical significance in patients with idiopathic myelofibrosis (IMF), genomic DNA was extracted from peripheral blood cell samples of 12 IMF cases. Allele-specific PCR (AS-PCR) was performed to identify JAK2V617F mutation, and the results were confirmed by sequence analysis. A retrospective study was performed to explore the correlation between JAK2V617F mutation and the clinical, hematologic features. The results showed that in follow-up for 2 to 15 months, the occurrence of the positive point mutation in 12 patients with IMF was 50%, and the half of these positive patients had thrombosis. Patients with JAK2V617F point mutation had a higher counts of platelets and megakaryocytes in bone marrow than those in patients without JAK2V617F point mutation. Out of other 6 IMF patients without JAK2V617F point mutation only 1 patient had thrombosis, and lower counts of platelets in peripheral blood and megakaryocytes in bone marrow. It is concluded that majority of IMF patients with positive JAK2V617F point mutation have typical clinical and hematologic features, higher incidence of thrombosis, and higher counts of platelets in peripheral blood and megakaryocytes in bone marrow.

Protective effect of O6-methylguanine-DNA-methyltransferase on mammalian cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>O(6)-methylguanine-DNA-methyltransferase (MGMT) is a specific DNA revising enzyme transferring alkylated groups from DNA to its cysteine residue to avoid the abnormal twisting of DNA. Therefore, it is one of the drug resistant genes targeted in the treatment of cancer. This study explored the protective effect of MGMT gene transferred into mammalian cells.</p><p><b>METHODS</b>Mammalian expression vector containing the MGMT gene cloned from human hepatocytes by RT-PCR was constructed and transferred into K562 cells and human peripheral blood mononuclear cells (PBMCs) via liposome, then assayed for gene expression at RNA and protein levels. MTT assay was used to check the drug resistance of cells transfected with MGMT gene.</p><p><b>RESULTS</b>MGMT gene was successfully cloned. Real-time PCR showed that the mRNA expression in gene transfected groups in K562 cell line and PBMC were 13.4 and 4.0 times that of the empty vector transfected groups respectively.</p><p><b>RESULTS</b>of Western blotting showed distinct higher expression of MGMT in gene transfected group than in other two groups. The IC(50) values increased to 7 and 2 times that of the original values respectively in stable transfected K562 cells and transient transfected PBMC.</p><p><b>CONCLUSION</b>The alkylating resistance of eukaryotic cells is enhanced after being transfected with MGMT gene which protein product performs the protective function, and may provide the reference for the protective model of peripheral blood cells in cancer chemotherapy.</p>