Mutations in DNA methyltransferase 3A (DNMT3A) gene were recently demonstrated in acute myeloid leukemia(AML). Approximately 20% patients with AML carry DNMT3A gene mutations and was associated with a poor clinical outcome. but its clinical implications in Chinese AML patients are largely unknown. We analyzed 101 adult AML patients in china and found 14 patients (13.9%) harboring this mutation. 9 patient with M5, 2 patients with M1, 2patient with M2 and 1 patient with M3. We identified 11 missense mutation,2 nonsense and 30 bp deletion encompassing DNMT3A. The most common of them was predicted to affect 882Arg(in 4 patients). Double mutations were detected in two cases.10 of 33(43.5%). DNMT3A mutations occurred more frequently in older (age > 50y,p < 0.05) and the outcome is too badly for these patients. We concluded that DNMT3A mutations are highly recurrent in AML and is associated with distinct clinical and biologic characteristics and seems to be a useful as a prognostic marker.

Histone deacetylase (HDAC) inhibitors are a new class of chemotherapeutic agents. Our laboratory has recently reported that phenylhexyl isothiocyanate (PHI), a synthetic isothiocyanate, is an inhibitor of HDAC. In this study we examined whether PHI is a hypomethylating agent and its effects on myeloma cells. RPMI8226, a myeloma cell line, was treated with PHI. PHI inhibited the proliferation of the myeloma cells and induced apoptosis in a concentration as low as 0.5 μM. Cell proliferation was reduced to 50% of control with PHI concentration of 0.5 μM. Cell cycle analysis revealed that PHI caused G1-phase arrest of RPMI8226 cells. PHI induced p16 hypomethylation in a concentration-dependent manner. PHI was further shown to induce histone H3 hyperacetylation in a concentration-dependent manner. It was also demonstrated that PHI inhibited IL-6 receptor expression and VEGF production in the RPMI8226 cells, and reactivated p21 expression. It was found that PHI induced apoptosis through disruption of mitochondrial membrane potential. For the first time we show that PHI can induce both p16 hypomethylation and histone H3 hyperacetylation. We conclude that PHI has dual epigenetic effects on p16 hypomethylation and histone hyperacetylation in myeloma cells and targets several critical processes of myeloma proliferation.

ObjectiveAberrant expression of miRNA (miR)-96 is associated with tumorigenesis and tumor progression in several solid cancers. However, little is known about the expression and prognostic value of miR-96 in acute myeloid leukemia (AML). Therefore, the aim of this study was to investigate the correlation of miR-96 expression with clinicopathological features and prognosis of AML.MethodsReal-time quantitative RT-PCR assay was performed to evaluate the expression levels of miR-96 in mononuclear cells from bone marrow or peripheral blood specimens in 86 patients with newly diagnosed AML.ResultsCompared with normal controls, miR-96 expression was significantly downregulated in patients with newly diagnosed AML (P < 0.001). In analysis of 14 diagnosis/CR-paired samples, the expression level of miR-96 was found markedly elevated in patients after treatment than before (P < 0.001). Moreover, lower levels of miR-96 were associated with a higher white blood cell count, bone marrow blast count (P < 0.001 and 0.022, respectively), and lower hemoglobin and platelet count (P = 0.036 and 0.033, respectively). Although the low-expression group seemed to have a lower CR rate (53.85% vs 70.0%), there was no significant difference between the two groups (P = 0.213). The low-expression group had a lower relapse-free survival (RFS) (P = 0.038) and overall survival (OS) (P = 0.022) compared with the high-expression group during a median follow-up of 20 months.ConclusionOur data demonstrated that the expression of miR-96 was downregulated in newly diagnosed AML patients and associated with leukemic burden, as well as RFS and OS. This suggests that miR-96 detection might become a potential biomarker of prognosis and monitoring in AML.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1434808553949498

Burkitt lymphoma (BL) has been reported to be strongly associated with Epstein-Barr virus (EBV) infection. The fact that EBV is generally present in cancer cells but rarely found in healthy cells represents an opportunity for targeted cancer therapy. One approach is to activate the lytic replication cycle of the latent EBV. Nuclear factor (NF)-κB is thought to play an essential role in EBV lytic infection. Elevated NF-κB levels inhibit EBV lytic replication. Parthenolide (PN) is a sesquiterpene lactone found in medicinal plants, particularly in feverfew ( Tanacetum parthenium ). The aim of the present study was to analyze the effect of PN on the survival of Raji EBV-positive lymphoma cells. Raji cells were treated with 0, 4 or 6 μmol/l PN for 48 h. MTT assay and western blot analysis were performed to evaluate the findings. Results showd that PN suppressed the growth of the EBV-positive BL cell line, Raji, and activated the transcription of BZLF1 and BRLF1 by inhibiting NF-κB activity. Most notably, when PN was used in combination with ganciclovir (GCV), the cytotoxic effect of PN was amplified. These data suggest that the induction of lytic EBV infection with PN in combination with GCV may be a viral-targeted therapy for EBV-associated BL.

BackgroundmiRNA is a microRNA that negatively regulates protein expression at post-transcriptional or translational level. It is widely involved in the pathogenesis of tumors. miR-98 belongs to the let-7 family, and its overexpression can increase the sensitivity to drugs in solid cancer cells. However, the function of miR-98 in leukemia is still unclear. In this study, the effect of miR-98 on drug resistance and proliferation of leukemia cells were investigated.MethodsReal-time quantitative polymerase chain reaction analyzed the expression difference between miR-98 and E2F1 in leukemia cell lines, K562 and K562/A02. The downstream target gene of miR-98 was predicted by TargetScan; K562/A02 was transiently transfected with miR-98 mimic to upregulate the expression of miR-98; real-time quantitative polymerase chain reaction and Western blot were used to analyze the expression alterations of E2F1; cell counting kit-8 was used to evaluate the influence on K562/A02 proliferation and sensitivity to chemotherapeutic drugs; meanwhile, Western blot was used to analyze the expression of p21, Bax, matrix metalloproteinase 9 and ABCG2 proteins.ResultsE2F1 is one of the target genes of miR-98 proved by bioinformatics. Compared with the K562, the level of miRNA-98 expression was decreased in K562/A02, but the level of E2F1 expression was upregulated. Leukemia cell line K562/A02 was transfected with miR-98 mimic to upregulate the expression of miR-98, the expression of E2F1 was significantly decreased. After upregulating the miR-98 expression in K562/A02, the proliferation was weakened, and the sensitivity to chemotherapy was increased. Western blot showed that upregulated miR-98 expression increased the levels of p21 and BAX proteins in K562/A02 cells, and decreased the levels of matrix metalloprotease 9 and ABCG2 proteins, which were significantly different compared with those before miR-98 mimic transfection.ConclusionIn the leukemia drug-resistant cell line K562/A02, the targeted upregulated expression of miR-98 could decrease the proliferation of leukemia cells and improve the sensitivity to chemotherapeutics by inhibiting E2F1 expression. miR-98 might be a potential target for overcoming leukemia multidrug resistance.

BackgroundHistiocytic sarcoma (HS) is a rare malignant tumor. Underlying or associated disorders have been reported in some patients with HS. We herein report a very rare case of HS combined with acute monocytic leukemia (AMoL).Case presentationA 62-year-old man presented with systemic lymph node enlargement and pancytopenia in August 2012. Bone marrow (BM) aspirate showed abnormal hematopoiesis with 3 % blast, but no obvious abnormalities on flow cytometric immunophenotyping. A BM cytogenetic study and fluorescence in situ hybridization revealed a 46, XY karyotype and no myelodysplastic syndrome-associated features, respectively. A right cervical node biopsy showed disrupted node structure with diffuse pleomorphic neoplastic cells that were positive for cluster of differentiation (CD) 68, MAC387 and lysozyme, but negative for CD1a, CD21, CD30, S100, and T-cell, B-cell, and myeloid lineage markers. The patient was diagnosed with HS and treated with 8 courses of CHOP chemotherapy. After 4 courses, total-body FDG-PET imaging showed partial remission and disappearance of abnormal hematopoiesis in the BM, but 2 % blasts remained. Lymphadenopathy and pancytopenia recurred 1 month after the his last chemotherapy dose. He became resistant to second-line chemotherapy, with gradually increasing leukocytes, up to 50 % blasts in BM in December 2013, and abnormal cells positive for CD117, CD13, CD33, HLA-DR, CD34, CD11c, CD38, and myeloperoxidase. He was diagnosed with acute monocytic leukemia (AMoL-M5), and treated by CAG regimen + decitabine, but died of severe pneumonia and hepatic failure.ConclusionTo our knowledge, this is the first case of HS combined with AMoL. The coexistence of these two neoplasms was shown by the lymph node biopsy findings and BM myeloid markers. The patient had a transient response to chemotherapy and a poor prognosis. Whether these two neoplasms were related is unclear; however, if so, we suspect the combination might be caused by a malignant transformation of a promonocyte or stem cell, upstream of histiocytes and monocytes.

Abstract. Acute myeloid leukaemia (AML) is a type of heterogeneous disease derived from haematopoietic stem cells. Cytogenetic characterisation is essential for diagnosis and prognosis stratification. Here, we present the case of a 43-year-old female diagnosed with leukaemia, who demonstrated a rare chromosomal change of t(11; 12) (p15; q13) along with a positive FLT3-ITD mutation. The patient had a white blood cell count of 76.41x10 9 /l. Bone marrow morphology revealed that monoblasts accounted for 25.5% of cells, and premonocytes accounted for 49.0%. This patient strongly responded to idarubicin and Ara-c (cytarabine) chemotherapy, which rapidly eliminated the leukaemia cell clones. However, the proliferation rate of the leukaemia cells was high during the intermission of chemotherapy. Subsequently, following two courses of chemotherapy, full haematological remission could not be attained. AML patients with t(11; 12) (p15; q13) combined with FLT3-ITD mutations are expected to have a short life expectancy; however, early haematopoietic stem cell transplantation therapy may improve the treatment outcome for these patients.

We report a rare pediatric chronic eosinophilic leukemia (CEL) case of an 8-year-old male whose leukemic cells carried t(1; 5)(q21; q33) chromosomal abnormality. Sequencing analysis confirmed a TPM3-PDGFRB fusion, and the breakpoint was the same as adult patient. Targeted therapy with imatinib induced a rapid hematologic response and reduction of TPM3-PDGFRB transcripts as monitored by reverse transcription real-time PCR (RT-qPCR). We then established an RT-qPCR assay applicable to detection of all possible PDGFRB fusions and also validated this assay in the patient. These data should provide a valuable reference for management of pediatric CEL.