miR-26b-5p suppresses proliferation and promotes apoptosis in multiple myeloma cells by targeting JAG1.

BACKGROUND: Though the levels of diagnosis and treatment of multiple myeloma (MM) have been largely improved recent years, the prognosis of these patients remain unacceptable. It is urgent for us to discover the exact mechanism and determine some new indicators for MM. MiRNAs play a critical role in the occurrence and progression of cancers, including MM. MiR-26b-5p has been reported to be closely related to cells proliferation in human pulmonary cancer, hepatocellular carcinoma and so on. MATERIAL AND METHODS: Here, we measured the expression of miR-26b-5p in MM samples and cell lines by real-time PCR. Then, Kaplan-Meier Curves were applied to assess the effect of miR-26b-5p expression on MM patients prognosis. Functionally, MTT assay and Flow cytometry were conducted to explore the functions of miR-26b-5p in cells proliferation and apoptosis. Furthermore, bioinformatics tools, Pearson's correlation coefficient analysis, gain-and loss of-function experiments and rescue experiment were used to determine the relationship between JAG1 and miR-26b-5p in MM cells. In addition, we also confirmed the role of JAG1 in MM cells proliferation and apoptosis by gain-and loss of-function experiments. RESULTS: Here, we reported for the first time that miR-26b-5p was under-expressed in MM by real-time PCR. Clinically, Kaplan-Meier Curves showed that MM patients with lower miR-26b-5p expression had worse prognosis. Functionally, MTT assay revealed that miR-26b-5p inhibited cells proliferation. Flow cytometry indicated that miR-26b-5p accelerated tumor cells apoptosis. Furthermore, bioinformatics tools, Pearson's correlation coefficient analysis gain-and loss of-function experiments showed that JAG1 was the target of miR-26b-5p in MM cells. And, gain-and loss of-function experiments for JAG1 confirmed that JAG1 was an oncogene in MM cells. What's more, rescue experiment showed that JAG1 mediated the function of miR-26b-5p in MM cells. CONCLUSION: MiR-26b-5p acts as a tumor suppressor through suppressing cells proliferation and inducing cells apoptosis via directly targeting JAG1 in MM. MiR-26b-5p could be a potential and ponderable tumor target for MM in future.

Abnormal vascular endothelial growth factor protein expression may be correlated with poor prognosis in diffuse large B-cell lymphoma: A meta-analysis.

OBJECTIVE: We conducted the present meta-analysis with relevant cohort studies to determine whether expression levels of vascular endothelial growth factor. (VEGF) could predict the prognosis of diffuse large B.cell lymphoma. (DLBCL). MATERIALS AND METHODS: The MEDLINE (1966-2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980-2013), CINAHL (1982--2013), Web of Science (1945-2013), and the Chinese Biomedical Database (1982-2013) were searched without any language restrictions. Meta-analysis was conducted using STATA software (Version 12.0, Stata Corporation, College Station, Texas USA). Hazard ratios (HR) and their corresponding 95% confidence intervals (95% CI) were calculated. RESULTS: Eight clinical cohort studies, which recruited a total 670 DLBCL patients, were included in the meta-analysis. The results of this meta-analysis indicate that DLBCL patients with positive VEGF expression had a shorter overall survival than those with negative VEGF expression. (HR = 1.58, 95% CI = 0.80-2.36, P < 0.001). Ethnicity-stratified analysis illustrates that high expression levels of VEGF may be significantly correlated with poor DLBCL prognosis among both Caucasian and Asian populations. (Caucasian: HR = 1.73, 95% CI = 0.56-2.90, P = 0.004; Asian: HR = 1.45, 95% CI = 0.41-2.50, P = 0.006). CONCLUSION: The major findings of our meta-analysis reveal that the aberrant expression of VEGF may correspond to shorter overall survival of patients with DLBCL, revealing that VEGF expression could be an unbiased prognostic determinant in the management of DLBCL patients.

[Clinical and molecular-biological study of a May-Hegglin anomaly family].

OBJECTIVE: To study the changes of platelet in May-Hegglin anomaly (MHA) and the molecular pathogenesis mechanism. METHODS: Peripheral blood was drawn from the MHA proband, her father and her uncle. Platelet count and morphology were examined by automatic blood cell counter and microscopy, respectively. The platelet membrane protein was examined by flow cytometry. Membrane antibodies were determined by ELISA. PCR was used to amplify the exons 25, 31 approximately 32, 38 and 40 of the MYH 9 gene in the MHA patient and her diseased father. Furthermore, PCR products were sequenced, a specific point mutation was identified and inclusions (Dohle's body) in the neutrophil was detected by indirect immunofluorescence technique. RESULTS: It was proved that in MHA patients, platelet count was higher by cell counter than by microscope (P < 0.01). Giant platelet was 94% but platelet membrane proteins (CD41, CD61, CD42A, CD42b) were in normal range. Membrane antibodies was undetectable. An A5521G mutation (GAG-->AAG) in the exon 38 was found in the proband and her diseased father, resulting in a characteristic change of NMMHC-A1841 (Glutamic acid-->Arginine), which was not found in other members of the family and in normal controls. Spindle-like inclusions with fluorescence were clearly displayed in neutrophil cytoplasm. CONCLUSION: The molecular pathogenesis mechanism of May-Hegglin anomaly is the mutation in MYH 9 gene.