MicroRNA-153-3p enhances the sensitivity of chronic myeloid leukemia cells to imatinib by inhibiting B-cell lymphoma-2-mediated autophagy.

Chronic myeloid leukemia (CML) is a hematopoietic stem cell disease caused by abnormal DNA replication of bone marrow stem cells and chemotherapy resistance is a major obstacle to the effective treatment of patients with CML. Imatinib (IM), a tyrosine kinase inhibitor (TKI), is a first-line drug clinically used for CML. Mounting evidence has indicated that the dysregulation of microRNAs (miRNAs) is associated with the chemoresistance of CML. In this study, miR-153-3p, which had been implicated with numerous types of tumors, was identified to be downregulated in IM-resistant CML cells. Upregulation of miR-153-3p significantly increased IM sensitivity and decreased the survival rate of IM-resistant CML cells, whereas downregulation of miR-153-3p attenuated these effects in IM-resistant CML cells. Upregulated miR-153-3p could decrease the autophagy caused by IM in IM-resistant CML cells. Dual-luciferase reporter assays confirmed that Bcl-2 is a direct target of miR-153-3p. Bcl-2 restoration reversed the increased sensitivity to IM induced by miR-153-3p-mimic transfection in IM-resistant CML cells. The results of the present study showed that dysregulated miR-153-3p may target Bcl-2 to promote the development of IM resistance and attenuate IM-induced apoptosis in CML. Therefore, miR-153-3p upregulation combined with IM treatment may serve as a promising therapeutic strategy for patients with low sensitivity.

[Establishing the Ion Torrent PGM Sequencing Methods for the Clinical Diagnosis of MPN Patients].

OBJECTIVE: To investigate the feasibility and relibility of rapidly and accurately acquiring the informations of gene mutations in MPN patients by using self-designed custom MPN mutation-related multipe-PCR primer kit and next generation Ion Torrent PGM sequencing platform. METHODS: The bone marrow samples of 10 MPN patients with JAK2V617F and/or CALR+, Ph- confirmed by sanger sequencing method were collected and were re-detected by using next generation Ion Torrent PGM sequencing method, then the consistence of results of above-mentioned 2 kinds of detection methods was compared. RESULTS: In terms of JAK2V617F, MPL and CALR mutations, the results of Ion Torrent PGM sequencing were complete consistent with results of Sanger sequencing, except 52 bp deletion of CALR gene, which conld not be detected by next generation Ion Torrent PGM sequencing method in all bone marrow samples. CONCLUSION: The detection of multiple gene mutations in MPN patients by Ion Torrent PGM sequencing platform is feasible and can meet the needs of clinical testing. This method can complete detection of all 23 mutetions within 1-2 days, moreover, possesses advantages of high sensitivity, specificity, rapidity, high throughput and low cost.

TNF-α enhances vascular cell adhesion molecule-1 expression in human bone marrow mesenchymal stem cells via the NF-κB, ERK and JNK signaling pathways.

The migration of circulating mesenchymal stem cells (MSCs) to injured tissue is an important step in tissue regeneration and requires adhesion to the microvascular endothelium. The current study investigated the underlying mechanism of MSC adhesion to endothelial cells during inflammation. In in vitro MSC culture, tumor necrosis factor­α (TNF­α) increased the level of vascular cell adhesion molecule­1 (VCAM­1) expression in a dose­dependent manner. The nuclear factor-κB (NF-κB), extracellular signal­regulated kinase (ERK) and c­Jun N­terminal kinase (JNK) signaling pathway inhibitors, pyrrolidine dithiocarbamate (PDTC), U0126 and SP600125, respectively, suppressed VCAM­1 expression induced by TNF­α at the mRNA and protein levels (P<0.05). TNF­α augmented the activation of NF­κB, ERK and JNK, and promoted MSC adhesion to human umbilical vein endothelial cells; however, the inhibitors of NF­κB, ERK and JNK did not affect this process in these cells. The results of the current study indicate that adhesion of circulating MSCs to the endothelium is regulated by TNF-α-induced VCAM-1 expression, which is potentially mediated by the NF­κB, ERK and JNK signaling pathways.

Correlation between deletion of the CDKN2 gene and tyrosine kinase inhibitor resistance in adult Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Frequency relapses are common in Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukemia (ALL) following tyrosine kinase inhibitors (TKIs). CDKN2A/B is believed to contribute to this chemotherapy resistance. METHODS: To further investigate the association between CDKN2 status and TKI resistance, the prevalence of CDKN2 deletions and its correlation with a variety of clinical features was assessed in 135 Ph-positive ALL patients using interphase fluorescence in situ hybridization (I-FISH). RESULTS: Results showed that no difference occurred between patients with CDKN2 deletion (44/135) and wild-type patients in sex, age, and complete remission (CR) rate following induction chemotherapy combined with tyrosine kinase inhibitors (TKIs). However, CDKN2 deletion carriers demonstrated higher white blood cell (WBC) count, enhanced rates of hepatosplenomegaly (P = 0.006), and upregulation of CD20 expression (P = 0.001). Moreover, deletions of CDKN2 resulted in lower rates of complete molecular response (undetectable BCR/ABL), increased cumulative incidence of relapse, short overall survival (OS), and disease-free survival (DFS) time (P < 0.05) even though these patients received chemotherapy plus TKIs followed by allogenic hematopoietic stem cell transplantation (Allo-HSCT). In the case of 44 patients who presented with CDKN2 deletion, 18 patients were treated with dasatinib treatment, and another 26 patients were treated with imatinib therapy, and our study found that there were no differences associated with OS (P = 0.508) and DFS (P = 0.555) between the two groups. CONCLUSIONS: CDKN2 deletion is frequently acquired during Ph-positive ALL progression and serves as a poor prognostic marker of long-term outcome in Ph-positive ALL patients with CDKN2 deletion even after the second-generation tyrosine kinase inhibitor treatment.

CDKN2 Gene Deletion as Poor Prognosis Predictor Involved in the Progression of Adult B-Lineage Acute Lymphoblastic Leukemia Patients.

Deletion of cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) is well known in many hematologic malignancies, but only few reports have investigated this deletion effect on clinical prognosis. This study performed analysis of the CDKN2 deletion in 215 adult B- lineage acute lymphoblastic leukemia (B-ALL) patients, and related cytogenetic prognostic factors (BCR/ABL; E2A/PBXl; TEL/AML1; Mixed Lineage Leukemia (MLL) rearrangement; MYC, Immunoglobulin heavy locus (IGH) translocation). The prevalence of CDKN2 deletions in all study populations was 28.4%. There is no difference between patients with CDKN2 deletion and wild-type patients in sex, age, white blood cells (WBC) count, BM blast percentage, extra infiltration and induction complete remission (CR) rate. Analysis in relapse patients revealed that the distribution of CDKN2 deletion is higher in relapse patients (44.6%) than all patients (28.4%, P=0.006). Deletion of CDKN2 was significantly associated with poor outcomes including decreased overall survival (OS) (P<0.001), lower disease free-survival (DFS) (P<0.001), and increased cumulative incidence of relapse (P=0.002); Also, CDKN2 deletion was strongly associated with IGH translocation (P=0.021); and had an adverse effect on patients with BCR-ABL fusion gene or with MLL rearrangement. Patients with CDKN2 gene deletion benefited from allogenic hematopoietic stem cell transplantation (Allo-HSCT). Deletion of CDKN2 gene was commonly observed through leukemia progression and was poor prognostic marker in long-term outcomes.

Prognostic Significance of Monosomal Karyotype in Adult Patients With Acute Myeloid Leukemia Treated With Risk-Adapted Protocols.

BACKGROUND: The monosomal karyotype (MK) is a well-known adverse prognostic factor and has been found to be related to poor outcome in patients with acute myeloid leukemia (AML). However, the outcome in MK-positive AML patients undergoing different therapies has not been well investigated. PATIENTS AND METHODS: We retrospectively analyzed clinical and laboratory features in 225 MK-positive AML patients. Clinical outcome of overall survival (OS) and disease-free survival (DFS) was evaluated in patients according to age group and in patients who received different therapy protocols. RESULTS: The proportion of MK-positive patients increased along with age. Also, patients who were treated with high-dose cytarabine (HD-Ara-C) as consolidation therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) demonstrated longer OS and DFS compared to allo-HSCT or HD-Ara-C alone. Patients treated with allo-HSCT alone exhibited longer DFS compared to patients treated with HD-Ara-C alone. No difference in OS was discovered between these 2 single protocols. CONCLUSION: MK was associated with a lower complete remission rate. HD-Ara-C therapy followed by allo-HSCT could improve the prognosis of MK-positive AML patients.

[TNF-α stimulates bone marrow mesenchymal stem cell VCAM-1 production by ERK signaling pathway].

This study was aimed to explore the effect of TNF-α on the vascular cell adhesion molecule 1 (VCAM-1) expression of human bone marrow mesenchymal stem cells (BMMSC) and the relationship between this process and ERK signalling pathway. BMMSC were isolated by density gradient centrifugation combined with adherent culture method, and then identified by surface antigen expression and differentiation potential. Flow cytometry was used to detect expression of VCAM-1 on BMMSC exposed to TNF-α at different concentrations, and the effect of ERK inhibitor U0126 on VCAM-1 of BMMSC. ERK signaling pathway activation was analyzed by Western blot. The results showed that BMMSC positively expressed CD29, CD69, CD44, CD105, and negatively expressed CD34, CD45. BMMSC could be induced to differentiate into osteoblasts and adipocytes. Flow cytometry analysis showed that after the TNF-α stimulation, the expression of VCAM-1 on BMMSC increased in a dose-dependent manner. And this increase was inhibited by U0126. TNF-α caused activation of ERK signal pathway, and U0126 suppressed this effect induced by TNF-α. It is concluded that TNF-α can increase expression of VCAM-1 of BMMSC via ERK signaling pathway.

[Dynamic of phytoplankton abundance and the relationship with environmental factors in Dianshan Lake, Shanghai].

During January 2004 to December 2006, the abundance of phytoplankton and environmental factors such as the water temperature, wind speed, transparency of water (SD), TN, TP, pH, and permanganate index were monitored monthly in Dianshan Lake. The water quality of Dianshan Lake was in the mid-eutrophication state. The correlation analysis between phytoplankton community and environmental factors were performed. It indicated that the phytoplankton abundance, cyanobacteria abundance in Dianshan Lake were positively correlated with temperature (r = 0.487, r = 0.497), pH (r = 0.415, r = 0.379) and permanganate index (r = 0.460, r = 0.436), and negatively correlated with SD (r = -0.382, r = -0.394). Chlorophyta abundance in Dianshan Lake was positively correlated with PO4(3-) -P (r = 0.466). There was also a significant positive correlation between phytoplankton abundance and cyanobacteria abundance (r = 0.970). According to (CCA) ordination analysis, temperature, DO, SD and PO4(3-) -P were main factors affecting dynamic characteristics of phytoplankton community. The meteorological and hydrological factors were more important than nutrition concentration related to the water bloom in Dianshan Lake.