Serum exosomal microRNAs as novel biomarkers for multiple myeloma.

Accumulating studies have focused on circulating microRNAs, which might be potential biomarkers for different malignancies. The aim of this study was to investigate the potential of serum exosomal microRNAs to be novel serum biomarkers for smouldering myeloma (SMM) or even multiple myeloma (MM). The levels of serum exosomal microRNAs and serum circulating microRNAs were measured in healthy individuals and patients with SMM (n = 20) or MM (n = 20). Serum exosomal microRNAs and serum circulating microRNAs were extracted from serum, and the expression levels of selected microRNAs were quantified by real-time polymerase chain reaction (PCR). The levels of serum exosome-derived miR-20a-5p, miR-103a-3p, and miR-4505 were significantly different among patients with MM, patients with SMM, and healthy individuals, while there were differences in the levels of let-7c-5p, miR-185-5p, and miR-4741 in patients with MM relative to those in SMM patients or healthy controls. Additionally, a significant correlation was rarely found between the levels of serum and exosomal microRNAs. This study shows that serum exosomal microRNAs can be used independently as novel serum biomarkers for MM.

Changes in the structure and hydration properties of high-temperature peanut protein induced by cold plasma oxidation.

To improve the hydration properties of high-temperature pressed peanut protein isolate (HPPI), we investigated the effect of cold plasma (CP) oxidation on functional and structural properties. Compared to HPPI, the hydrated molecules number and the surface contact angle were significantly decreased at 70 W, from 77.2 × 109 to 17.7 × 109 and from 85.74° to 57.81°, respectively. The reduction of the sulfhydryl content and the increase of the disulfide bond and di-tyrosine content indicated that the structural transformation was affected by the oxidation effect. In terms of structural changes, a stretched tertiary structure, ordered secondary structure, and rough apparent structure were observed after CP treatment. Additionally, the enhancement of surface free energy and group content such as -COOH, -CO and -OH on the surface of HPPI contributed to the formation of hydrated crystal structures. In general, the oxidation effect of CP effectively improved the hydration properties of HPPI and broaden its application field.

Potential Relationship between Clinical Significance and Serum Exosomal miRNAs in Patients with Multiple Myeloma.

This study evaluated the potential relationship between exosomal miRNAs and clinical symptoms in patients with multiple myeloma (MM). Forty-eight newly diagnosed myeloma patients and sixteen normal donors were enrolled in the study. The results showed that the relative expression levels of let-7c-5p, let-7d-5p, miR-140-3p, miR-185-5p, and miR-425-5p in the exosomes of MM patients were significantly lower than those of healthy controls. Furthermore, there were significant differences in the clinical characteristics of myeloma, such as kidney damage, while the expression levels of the same miRNA in exosomes and serum are not correlated. The expression of exosomal miRNA is related to the expression levels of clinical feature-related factors, such as creatinine, ß2-microglobulin, ß-CTX, and IL-6 in serum. Establishing this relationship could contribute to understanding the pathogenesis of MM.

[Effect of GRK6 on Proliferation of Multiple Myeloma MM1R Cells and Its Mechanism].

OBJECTIVE: To explore the regulatory effect of GRK6 on the proliferation of multiple myeloma cells and its mechanism. METHODS: A lentivirus vector shRNA interfering in human GRK6 gene expression was constructed and trans-fected into multiple myeloma cells to obtain the cell line MM1R with stable down-regulation of GRK6 gene expression. The real-time quantitative PCR and Western blot were used to confirm the effectiveness of the GRK6 gene expression down-regulation mediated by lentivirus vector. The MM1R cells with most obvious down-regulation were selected to detect the effect of GRK6 gene on cell proliferation. RESULTS: The lentivirus vector GRK6-shRNA interfering in human GRK6 gene was constructed succesufully and transfected into multiple myeloma cells, thereby the MM1R cell line with stable down-regulation of GRK6 gene was obtained. The CCK-8 assay showed that the proliferative viability of MM1R cells in experimental group was significantly lower than that in control group (P<0.05); the flow cytometry showed that cells in experimental group were arrested in G0/G1 phase(P<0.05); the Western blot detection showed that the Cyclin D1 and CDK4 levels in experiment group obviously decreased as compared with control group. CONCLUSION: A lentivirus vector which can specifically interfere in GRK6 gene expression is constructed successfully, The MM1R cell line with stable down-regulation of GRK6 expression is obtained by transfection and screening. The down-regulation of GRK6 expression can arrest MM1R cells in G0/G1 phase, moreover inhibits the proliferation of MM1R cells by inhibition of Cyclin D1 and CDK4 levels.

[Effect of ADAM10 Inhibitor GI254023X on Proliferation and Apoptosis of Multiple Myeloma H929 Cells and Its Possible Mechanisms].

OBJECTIVE: To investigate the effect of ADAM10 inhibitor GI254023X on the proliferation and apoptosis of multiple myeloma H929 cell line and its mechanisms. METHODS: H929 cells were treated with different concentrations of GI254023X, the proliferation-inhibitive curve was assayed and plotted by CCK-8 method, the cell viability and apoptosis were detected by flow cytometry with Annexin V/7-AAD double staining. The cleavage of Notch1 protein (cleaved notch1) was determined by Western blot. The transcripts of Notch1 target gene Hes-1 were detected by real-time PCR. RESULTS: The GI254023X inhibited the proliferation of H929 cells in the time- and dose- dependent manners. As compared with the control group, the apoptosis of cells increased along with enhancement of GI254023X concentration; The expression of cleaved Notch1 was down-regulated after the treatment with GI254023X. The levels of Hes-1 mRNA transcripts in H929 cells was reduced in GI254023X treated group. CONCLUSION: GI254023X can remarkably inhibit the proliferation and induce the apoptosis of H929 cells. Its mechanism may be associated with inbihition of Notch1 activation.