LncRNA MEG3 negatively modified osteosarcoma development through regulation of miR-361-5p and FoxM1.

This study was aimed to figure out whether long noncoding RNA MEG3/miR-361-5p/FoxM1 signaling would contribute to improved proliferation and metastasis of osteosarcoma cells. We altogether collected 204 pairs of osteosarcoma tissues and adjacent normal tissues, and obtained four human osteosarcoma cell lines. Then pcDNA3.1-MEG3, si-MEG3, miR-361-5p mimic, miR-361-5p inhibitor, pcDNA3.1-FoxM1, si-FoxM1, and negative control (NC) were, respectively, transfected into the osteosarcoma cells. Furthermore, real time polymerase chain reaction was utilized to determine the mRNA expressions of maternally expressed gene 3 (MEG3) and miR-361-5p, and western blot analysis was applied for determining the FoxM1 expression. Besides, dual luciferase reporter gene assay was adopted to verify if MEG3 can be directly targeted by miR-361-5p. Finally, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, colony formation assay, flow cytometry, wound healing assay, and transwell assay were conducted to investigate the influence of MEG3, miR-361-5p, and FoxM1 expressions on the viability, proliferation, apoptosis, migration, and invasion of osteosarcoma cells. MEG3 and miR-361-5p were observed to be significantly downregulated within both osteosarcoma tissues and cell lines, whereas FoxM1 was upregulated in osteosarcoma tissues and cell lines (p < 0.05). MEG3 directly bound to miR-361-5p, and significantly upgraded its expression (p < 0.05). The upregulated MEG3 and miR-361-5p or the downregulated FoxM1 appeared to substantially inhibit proliferation, migration, and invasion of osteosarcoma cells (p < 0.05). Finally, the proliferation, migration, invasion, and motility of osteosarcoma cells within the miR-NC + pcDNA3.1-FoxM1 group and pcDNA + pcDNA-FoxM1 group were markedly promoted when compared with the miR-361-5p mimic group and pcDNA3.1-MEG3 group (p < 0.05). The MEG3/miR-361-5p/FoxM1 axis could potentially serve as therapeutic targets or diagnostic biomarkers for osteosarcoma.

Shen B ，Zhou N ，Hu T ，Zhao W ，Wu D ，Wang S ... -  《-》

The Effect of LncRNA H19/miR-194-5p Axis on the Epithelial-Mesenchymal Transition of Colorectal Adenocarcinoma.

Since the combined actions of lncRNAs and miRNAs have been considered to be involved in the occurrence and development of various neoplasms, the main purpose of this study was to discover whether and how lncRNA H19 and miR-194 influenced the epithelial-mesenchymal transition (EMT) process of colorectal adenocarcinoma (CRA). Totally 214 pairs of CRA and adjacent normal tissues were collected, and 5 human CRA cell lines (i.e. HCT116, HT-29, RKO SW280 and Lovo) were purchased. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was adopted to quantify the H19 and miR-194-5p expressions in cells and tissues. The expressions of FoxM1, E-cadherin, vimentin, N-cadherin were determined using western blot. On the side, si-H19, si-NC, miR-194-5p mimic, miR-194-5p inhibitor and negative control (NC) were transfected into CRA cell lines. Meanwhile, the invasive, migratory and proliferative conditions of the cells were assessed through transwell, wound healing and colony-forming experiments, with final verification of the relationship between H19 and miR-194-5p employing dual-luciferase reporter gene assay. Highly-expressed H19, lowly-expressed miR-194-5p, low-grade differentiation and lymph node metastasis appeared as the independent predictors of unfavorable prognosis in CRA patients' (all P< 0.05). It indicated that FoxM1 expression displayed positive correlations with H19 expression, yet negative associations with miR-194-5p expression within CRA tissues (P< 0.05). In addition, transfection of H19-siRNA and miR-145-5p mimic triggered a conspicuous increase in E-cadherin expression, as well as an evidently down-regulation in vimentin and N-cadherin expressions within HT29 and RKO cells (P< 0.05). On the other hand, the invasive and migratory capacities of CRA cells were significantly hindered (P< 0.05). Moreover, the luciferase reporter gene assay confirmed that H19 modified miR-194-5p expression through directly targeting at it (P< 0.05). Ultimately, FoxM1 could reverse the role of miR-194-5p in inhibiting invasion, migration and EMT of CRA cells (P< 0.05). LncRNA H19/miR-194/FoxM1 axis could serve as a profound target for the diagnosis and treatment of CRA.

Li CF ，Li YC ，Wang Y ，Sun LB ... -  《-》

lncRNA MEG3 modified epithelial-mesenchymal transition of ovarian cancer cells by sponging miR-219a-5p and regulating EGFR.

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR-219a-5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov-3, OVCAR-3, and SKOV-3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1-MEG3, si-MEG3, miR-219a-5p mimic, miR-219a-5p inhibitor, pcDNA3.1-EGFR, and si-EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual-luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR-219a-5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR-219a-5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR-219a-5p (P < .05). In addition, the OC cells transfected with si-MEG3 or miR-219a-5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si-MEG3 and miR-219a-5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR-219a-5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR-219a-5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR-219a-5p on the above-mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR-219a-5p/EGFR axis.

Wang L ，Yu M ，Zhao S 《-》

[LncRNA LINC-PINT regulating proliferation and apoptosis of osteosarcoma cells by targeting miR-524-5p].

Yang H ，Cao C ，Wang LJ 《-》

MiR-216b inhibits osteosarcoma cell proliferation, migration, and invasion by targeting Forkhead Box M1.

Osteosarcoma (OS) is considered the most common type of primary malignant bone tumor, which has a high rate of mortality in children and adolescents. However, the current treatment methods for OS are ineffective. Therefore, there is an urgent requirement to identify the critical targets. This study aimed to identify the roles and significance of microRNA-216b (miR-216b) in OS. To explore the cellular and molecular functions of miR-216b and Forkhead Box M1 (FoxM1) in OS, the expression of miR-216b and FoxM1 at the transcriptional level was measured using quantitative real-time PCR (qRT-PCR). Wound healing assay, 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide assay (MTT) assay, flow cytometry, and transwell invasion assay were conducted to study the function of miR-216b and FoxM1 in OS cells. Dual luciferase reporter assay was performed to identify the relationships between miR-216b and FoxM1. qRT-PCR results revealed that miR-216b expression was significantly downregulated, and FoxM1 was observed to be significantly upregulated in human OS cell lines (MG-63) and tissues. MTT data showed that upregulation of miR-216b expression led to cell growth inhibition in MG-63 cells. The results of the invasion assay and wound healing assay illustrated that miR-216b upregulation or FoxM1 downregulation could inhibit the invasion and migration in MG-63 cells. In vivo, the tumor volume was significantly decreased by miR-194 mimic treatment compared with the control group. Furthermore, the results of the luciferase assay indicated that FoxM1 is a direct target of miR-216b. These findings may provide novel insights into the molecular mechanism of miR-216b and FoxM1 in the progression of OS, and suggested that miR-216b may serve as a potential tumor inhibitor of OS by targeting FoxM1.

Wang W ，Guo Z ，Yu H ，Fan L ... -  《-》