MiR-203a-5p Inhibits Multiple Myeloma Cell Proliferation and Cell Cycle Progression via Targeting JAG1 / 中国实验血液学杂志

OBJECTIVE@#To investigate the biological function of miR-203a-5p and the underlying mechanism in multiple myeloma (MM).@*METHODS@#Three miRNA expression profiles (GSE16558, GSE24371 and GSE17498) were downloaded from the GEO database. The three miRNA expression profiles contained 131 MM samples and 17 normal plasmacyte samples. The robust rank aggregation (RRA) method was used to identify the differentially expressed miRNAs between MM and normal plasmacytes. In order to carry out cytological experiments, MM cell line with stable over-expression of miR-203a-5p was constructed with lentivirus. Expression levels of miR-203a-5p in MM cells were quantified by qRT-PCR. The effects of miR-203a-5p on MM cells were investigated using assays of cell viability and cell cycle. Cell proliferation was measured using the Cell Counting kit (CCK)8 assay. The percentage of cells in each cell cycle was measured with a FACSCalibur system. Xenograft tumor models were established to evaluate the role of miR-203a-5p in tumorigenesis in vivo . To elucidate the underlying molecular mechanisms of miR-203a-5p in mediating cell proliferation inhibition and cell cycle arrest in MM, we used TargetScan and miRanda to predict the candidate targets of miR-203a-5p. The potential target of miR-203a-5p in MM cells was explored using the luciferase reporter assay, qRT-PCR, and Western blot.@*RESULTS@#An integrated analysis of three MM miRNA expression datasets showed that the levels of miR-203a-5p in MM were notably downregulated compared with those in normal plasmacytes. Accordingly, the relative expression levels of miR-203a-5p were decreased in MM cell lines. In addition, overexpression of miR-203a-5p inhibited the proliferation and cell cycle progression of RPMI8226 and U266 cells. In vivo experiments demonstrated that upregulation of miR-203a-5p expression could significantly inhibit the tumorigenesis of subcutaneous myeloma xenografts in nude mice. Mechanistic investigation led to the identification of Jagged 1 (JAG1) as a novel and direct downstream target of miR-203a-5p. Interestingly, the reintroduction of JAG1 abrogated miR-203a-5p-induced MM cell growth inhibition and cell cycle arrest.@*CONCLUSION@#Our data demonstrate that miR-203a-5p inhibits cell proliferation and cell cycle progression in MM cells by targeting JAG1, supporting the utility of miR-203a-5p as a novel and potential therapeutic agent for miRNA-based MM therapy.

Expression and clinical significance of PDCD5 in patients with acute myeloid leukemia / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was aimed to investigate the roles of PDCD5 (programmed cell death 5) in pathogenesis of acute myeloid leukemia (AML) and the relevance of PDCD5 with the clinical characteristics and prognosis of patients by testing the PDCD5 expression in adult AML patients.</p><p><b>METHODS</b>The mRNA and intracellular protein levels of PDCD5 from 36 newly diagnosed AML patients were analyzed by real-time fluorescence quantitative polymerase chain reaction (RQ-PCR) and flow cytometry (FCM), respectively. The correlation of mRNA levels and intracellular protein levels of PDCD5 with the clinical characteristics and survival time of patients were analyzed.</p><p><b>RESULTS</b>The intracellular protein expression levels of PDCD5 in AML patients were significantly higher than those in normal controls (P < 0.05). The PDCD5 mRNA levels were not significantly different between patients and controls (P > 0.05). The mRNA and protein levels of PDCD5 did not significantly correlate with sex, age, WBC count, FAB subtype, extramedullary infiltration, WT1 gene, NPM1 gene mutation and the patients response to induction therapy. The patients with positive FLT3/ITD mutation displayed higher protein levels of PDCD5 as compared with negative FLT3/ITD mutation patients (P < 0.05).</p><p><b>CONCLUSION</b>The intracellular protein of PDCD5 significantly increased in AML patients. However, the increased PDCD5 does not exert the pro-apoptotic effects on AML cells. The patients with positive FLT3/ITD mutation show higher protein levels of PDCD5.</p>

Expression and clinical significance of B-cell lymphoma 2 (BCL-2) in hyperleukocytic acute myeloid leukemia / 中国实验血液学杂志

This study was aimed to investigate the role of B-cell lymphoma 2 (BCL-2) in pathogenesis of hyperleukocytic acute myeloid leukemia (AML). The levels of intracellular BCL-2 in 48 AML patients were detected by flow cytometry (FCM). Serum levels of BCL-2 in 40 AML patients were measured by enzyme-linked immunosorbent assay (ELISA). The results showed that the serum levels of BCL-2 in hyperleukocytic AML and non-hyperleukocytic AML patients were significantly higher than that in normal controls (P < 0.05), but intracellular BCL-2 levels were not significantly different, as compared with normal controls (P > 0.05). There were no difference of intracellular and serum BCL-2 levels between hyperleukocytic and non-hyperleukocytic AML patients (P > 0.05). The serum and intracellular levels of BCL-2 between hyperleukocytic AML, non-hyperleukocytic AML patients and normal controls were not statistically correlated. It is concluded that leukemic cells in AML patients produce and secrete too much BCL-2, which may be involved in the pathogenesis of leukemia disease. However, the anti-apoptosis effect of BCL-2 has no significant impact on the pathogenesis of hyperleukocytic AML.