[Role and mechanism of platelet-derived growth factor BB in thrombocytosis in Kawasaki disease]. / è¡€å°æ¿è¡ç”Ÿç”Ÿé•¿å› å­BBåœ¨å·å´Žç— è¡€å°æ¿å¢žå¤šä¸­çš„ä½œç”¨åŠæœºåˆ¶ç ”ç©¶.

OBJECTIVES: To study the role and mechanism of platelet-derived growth factor BB (PDGF-BB) on platelet production in Kawasaki disease (KD) mice and human megakaryocytic Dami cells through in vitro and invivo experiments. METHODS: ELISA was used to measure the expression of PDGF in the serum of 40 children with KD and 40 healthy children. C57BL/6 mice were used to establish a model of KD and were then randomly divided into a normal group, a KD group, and an imatinib group (30 mice in each group). Routine blood test was performed for each group, and the expression of PDGF-BB, megakaryocyte colony forming unit (CFU-MK), and the megakaryocyte marker CD41 were measured. CCK-8, flow cytometry, quantitative real-time PCR, and Western blot were used to analyze the role and mechanism of PDGF-BB in platelet production in Dami cells. RESULTS: PDGF-BB was highly expressed in the serum of KD children (P<0.001). The KD group had a higher expression level of PDGF-BB in serum (P<0.05) and significant increases in the expression of CFU-MK and CD41 (P<0.001), and the imatinib group had significant reductions in the expression of CFU-MK and CD41 (P<0.001). In vitro experiments showed that PDGF-BB promoted Dami cell proliferation, platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). Compared with the PDGF-BB group, the combination group (PDGF-BB 25 ng/mL + imatinib 20 µmol/L) had significantly lower levels of platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). CONCLUSIONS: PDGF-BB may promote megakaryocyte proliferation, differentiation, and platelet production by binding to PDGFR-ß and activating the PI3K/Akt pathway, and the PDGFR-ß inhibitor imatinib can reduce platelet production, which provides a new strategy for the treatment of thrombocytosis in KD.

Epigenetic silencing of miR-335 induces migration by targeting insulin-like growth factor-1 receptor in multiple myeloma.

Multiple myeloma (MM) is a common hematological malignancy and remains incurable. MiRNA-335 is a classic tumor suppressor, yet its expression pattern and biological role in MM is unclear. The aim of the present study was to determine the expression pattern, biological role, and mechanism of miR-335 in MM. In this study, we found that miR-335 expression was decreased in MM. The promoter of miR-335 was also hypermethylated in MM. It was found that over-expression of miR-335 or 5-azacytidine treatment suppressed migration of MM cells and down-regulated the expression of IGF-1R. MiR-335 thus acts as a metastatic suppressor by targeting IGF-1R in MM. Moreover, aberrant promoter hyper-methylation is critical for miR-335 silencing in MM. We also found that miR-335 assisted in predicting both the prognosis and progression of disease in MM patients. Observations might offer a new complementary diagnostic and therapeutic target in MM.

Analytical Value of Cell-Free DNA Based on Alu in Psychiatric Disorders.

Psychiatric disorders impose a huge burden on individuals, families, and society. The Alu repeat sequence is a member of the short interspersed nuclear element (SINE) family of mammalian genomes, however, its expression pattern and role in psychiatric disorders is unclear. The current paper aimed at determining the concentrations of Alu in patients with schizophrenia (SZ), major depressive disorder (MDD), and alcohol-induced psychotic disorder (AIPD), and to further define the role and value of Alu as a potential biomarker in psychiatric disorders. In this work, we found that the concentration of Alu was considerably incremented in patients with SZ, and a significant difference existed between patients diagnosed with SZ and MDD or AIPD. ROC analysis also indicated that Alu was effective in the complementary diagnosis of SZ, and differentially diagnosed between SZ patients and patients with MDD or AIPD. In addition, we found a positive relationship between the Alu concentrations and interleukin-1ß (IL-1ß) in patients with SZ, MDD, and AIPD, and between the concentrations of Alu and interleukin-18 (IL-18) in patients with SZ. Overall, the present work indicates that Alu might be an innovative biomarker for diagnosing psychiatric disorders, and provides the basis for hypotheses about the pathophysiology of psychiatric disorders.

[Effect of miR-202 on the growth of multiple myeloma cells via regulating B cell-activating factor and the underlying mechanism].

OBJECTIVE: To explore the regulating effect of miR-202 on B cell-activating factor, and check whether the regulation influences the growth of multiple myeloma cells. METHODS: The potential binding sites of BAFF for miR-202 were predicted using bioinformatics software. Luciferase reporter gene analysis was used to evaluate the regulatory effect of miR-202 on BAFF. Human multiple myeloma U266 cells were transfected with has-miR-202-mimics, has-miR-202-inhibitor, siBAFF and their negative controls, respectively. After above treatments, BAFF mRNA and protein levels were detected by real-time PCR and Western blot analysis, and the proliferation and apoptosis in the multiple myeloma (MM) cells were examined by WST-1 and annexin V-FLUOS assay, respectively. RESULTS: The BAFF mRNA expression levels in the untransfected group, has-miR-202-3P-mimics transfected group, has-miR-202-3P-inhibitor transfected group and siBAFF transfected group were 1.040 ± 0.057, 0.573 ± 0.073, 1.205 ± 0.097 and 0.368 ± 0.052, respectively. BAFF mRNA expressions in U266 cells transfected with has-miR-202-3P-mimics and siBAFF were significantly decreased compared with that in the untransfected group (P < 0.05). The BAFF protein expression level of each group was consistent with the mRNA assay result. The absorbance value in 450 nm of the untransfected group, has-miR-202-3P-mimics transfected group, has-miR-202-3P-inhibitor transfected group and siBAFF transfected group were 1.063 ± 0.052, 0.714 ± 0.045, 0.936 ± 0.066 and 0.764 ± 0.053, respectively. In comparison with the untransfected group, the absorbance value at 450 nm of has-miR-202-3P-mimics and siBAFF transfected groups was significantly reduced (P < 0.05). The cell apoptosis rates of untransfected group, has-miR-202-3P-mimics transfected group, has-miR-202-3P-inhibitor transfected group and siBAFF transfected group were 26.2%, 49.6%, 21.1% and 30.7%, respectively. Therefore, the cell apoptosis rate of has-miR-202-3P-mimics transfected group was significantly increased than that of the untransfected group (P < 0.05). p-JNK protein expression level was decreased in the has-miR-202-3P-mimics transfected cells. CONCLUSIONS: MiR-202 can inhibit the proliferation and induce apoptosis in MM cells via regulating BAFF. JNK/SAPK signaling pathway is involved in the regulation of BAFF by miR-202.

[Effects of the inhibitor of NF-kappaB and IFN-gamma on BAFF-R gene promoter activity].

AIM: To investigate the effects of IFN-gamma and the inhibitor of NF-kappaB(BAY11-7082) on BAFF-R gene promoter activity. METHODS: The fragments with different lengths of the 5'-flanking region of BAFF-R gene were amplified by PCR.Then PCR products were cloned into Luciferase reporter vector (pGL3-Basic) to construct eight recombinant plasmids. These recombinant plasmids were transiently transfected into KM3 cells to locate the promoter region with the highest activity. Then cells transfected with recombinant plasmid with the highest promoter activity were cultured on media in the absence or presence of IFN-gamma and BAY11-7082 and relative luciferase activity were tested and compared. Meanwhile BAFF-R mRNA expression were also examined and compared before and after IFN-gamma and BAY11-7082 were added into cell medium. RESULTS: IFN-gamma can promote BAFF-R promoter activity and up-regulate BAFF-R mRNA expression. And BAY11-7082 can inhibit BAFF-R promoter activity and down-regulate BAFF-R mRNA expression. CONCLUSION: IFN-gamma and the NF-kappaB pathway could be involved in regulating the transcription and mRNA expression of BAFF-R gene.