[Inhibitory Effect of Resveratrol on the Proliferation of Multiple Myeloma Cells and the Underlying Mechanism].

OBJECTIVE: To investigate the effect of resveratrol (RSV) on the proliferation of multiple myeloma (MM) cells and its molecular mechanism. METHODS: MM cells (MM1.S, RPMI-8226 and U266) were treated with different concentrations of RSV for 24-72 h. The effect of RSV on the proliferation of MM cells was detected by CCK-8 (cell counting kit-8) assay. RPMI-8226 cells were divided into RSV, miR-21 mimic, RSV+miR-21 mimic, miR-21 inhibitor and RSV+miR-21 inhibitor groups, and transfected with corresponding plasmids. The cell cycle distribution of each group was detected by flow cytometry with propidium iodide (PI) single staining. The cell apoptosis of each group was detected by AnnexinV-FITC/PE-PI double staining. The expression of miR-21 in MM cells treated with RSV and the expression of KLF5 mRNA in each group were detected by qRT-PCR. The expression of KLF5 protein in each group was detected by Western blot. RESULTS: RSV inhibited the proliferation and induced apoptosis of MM cells in a time- and dose-dependent manner. After the MM cells were treated with RSV, the number of cells in sub-G1 phase was increased, and that in G2/M phase was decreased. Moreover, RSV significantly downregulated the expression of miR-21 in MM cells, and the inhibitory effect of miR-21 mimic on KLF5 expression in MM cells was counteracted by RSV. CONCLUSION: RSV may inhibit the proliferation and induce apoptosis of MM cells by inhibiting miR-21 and up-regulating KLF5 expression.

[MiR-21 Regulates the Proliferation of Multiple Myeloma Cells by Inhibiting the Expression of KLF5].

OBJECTIVE: To study the expression of miR-21 in multiple myeloma (MM) cell lines and plasma cells of patients, and explore the mechanism of miR-21 in MM. METHODS: Bone marrow samples from 30 patients with MM and 18 healthy controls were collected. The plasma cells were separated by magnetic beads. MM cell lines (MM1.S cells, RPMI-8226 cells and U266 cells) were cultured. The expression level of miR-21 was detected by real-time fluorescent quantitative PCR (qRT-PCR). After transfection with hsa-miR-21 mimics and hsa-miR-21 inhibitor, the proliferation of MM cells was detected by CCK-8 and cell cloning assay. The target genes regulated by miR-21 were predicted by bioinformatics website. The binding sites of miR-21 and KLF5 were detected by luciferase reporter gene assay. The expression of KLF5 were detected by Western blot and qRT-PCR after hsa-miR-21 mimics and hsa-miR-21 inhibitor were transfected into RPMI-8226 cells. KLF5 plasmid with 3'UTR knockout was synthesized and cotransfected into RPMI-8226 cells with hsa-miR-21 mimics, and the proliferation of MM cells was detected by CCK-8 and cell cloning assay. RESULTS: Compared with healthy donors, the expression level of miR-21 in plasma cells of patients with MM was significantly increased (P<0.001); the expression of miR-21 in MM cell lines MM1.S, RPMI-8226 and U266 was significantly higher than that in control group (P<0.05). After hsa-miR-21 mimics transfection, the proliferation and the number of colony formation of MM cells was significantly increased, while the proliferation and the number of colony formation of MM cells was decreased after hsa-miR-21 inhibitor transfection (P<0.01). The results of luciferase reporter gene assay showed that miR-21 could bind to 3'UTR of KLF5, and the expression level of KLF5 protein was significantly decreased after hsa-miR-21 mimics transfection. After 3'UTR-knockout KLF5 plasmid and hsa-miR-21 mimics were cotransfected into RPMI-8226 cells, the proliferation of the cells was significantly decreased. CONCLUSION: MiR-21 may be involved in regulating the proliferation of MM cells by inhibiting the expression of KLF5.

Long noncoding RNA LINC00314 facilitates osteogenic differentiation of adipose-derived stem cells through the hsa-miR-129-5p/GRM5 axis via the Wnt signaling pathway.

BACKGROUND: Many studies have shown that long noncoding RNAs (lncRNAs) are closely related to the stimulation of osteogenic differentiation of adipose-derived stem cells (ADSCs) and the prevention of osteoporosis. Current research aimed to investigate the novel lncRNA and explored the function and molecular mechanism of the LINC00314/miR-129-5p/GRM5 axis in regulating osteogenic differentiation of ADSCs. METHODS: LncRNA and miRNA sequencing was performed in normal and osteogenic differentiation-induced ADSCs (osteogenic group). Abnormally expressed lncRNAs and miRNAs were obtained by the R software and the relative expression of LINC00314, miR-129-5p, and GRM5 during osteogenic induction was measured by RT-PCR. ADSCs were then transfected with pcDNA3.1-sh-LINC00314 and agomiR-129-5p. Alizarin red staining (ARS) and alkaline phosphatase (ALP) staining were performed to identify the mechanism of the LINC00314/miR-129-5p/GRM5 axis in regulating osteogenic differentiation of ADSCs. RESULTS: LINC00314 was significantly upregulated in the group of osteogenic-induced ADSCs. LINC00314 and GRM5 mimics increased the early and late markers of osteogenic differentiation, which manifest in not only the markedly increased ALP activity but also higher calcium deposition, while miR-129-5p mimic had the opposite effects. LINC00314 directly targeted miR-129-5p through luciferase reporter assay, and miR-129-5p suppressed GRM5 expression. Moreover, the LINC00314/miR-129-5p/GRM5 regulatory axis activated the Wnt/ß-catenin signaling pathway. CONCLUSIONS: LINC00314 confers contributory function in the osteogenic differentiation of ADSCs and thus the LINC00314/miR-129-5p/GRM5 axis may be a novel mechanism for osteogenic-related disease.