MicroRNA‑499a‑5p inhibits osteosarcoma cell proliferation and differentiation by targeting protein phosphatase 1D through protein kinase B/glycogen synthase kinase 3β signaling

Abstract

A number of studies have attempted to elucidate the association between mircoRNAs (miRNAs/miRs) and cancer-associated processes. The aim of the present study was to determine how miR-499a-5p intervenes in human osteosarcoma cell proliferation and differentiation. The cancerous tissues and adjacent non-cancerous tissues of 62 patients with osteosarcoma (OS) were collected. miRNA microarray analysis revealed that 29 miRNAs were upregulated while 26 were downregulated, among which miR-499a-5p expression was the most decreased. Western blot analysis and reverse transcription-quantitative polymerase chain reaction demonstrated that the mRNA and protein expression of miR-499a-5p was lower, while that of protein phosphatase 1D (PPM1D) was higher in OS tissues compared with expression levels in normal tissues. Furthermore, miR-499a-5p expression was markedly decreased in the metastatic tumors and in those at stage III+IV compared with the non-metastatic tumors and those at stage I, respectively. In addition, following transfection of the human OS MG-63 cell line with an miR-499a-5p mimic, the expression of miR-499a-5p was elevated while the protein and mRNA expression of PPM1D was decreased. When combining these findings with the information obtained from the Targetscan predictive software, it was confirmed that PPM1D was targeted by miR-499a-5p. In MG-63 cells transfected with an miR-499a-5p mimic, PPM1D-associated downstream proteins phosphorylated protein kinase B (p-Akt) and phosphorylated glycogen synthase kinase 3β (p-GSK-3β) were significantly downregulated compared with the negative control (NC) group, while the expression of p-Akt and p-GSK-3β were significantly elevated in the tumor tissues compared with the adjacent non-tumor tissues. Simultaneously, the growth and proliferation activity of MG-63 cells were notably reduced when transfected with the miR-499a-5p mimic, compared with the NC group. Therefore, it may be concluded that miR-499a-5p suppresses OS cell proliferation and differentiation by targeting PPM1D through modulation of Akt/GSK-3β signaling.

Downregulation of miR-499a-5p Predicts a Poor Prognosis of Patients With Non-Small Cell Lung Cancer and Restrains the Tumorigenesis by Targeting Fibroblast Growth Factor 9

“…These results were consistent with previous finding on the antiproliferative activity of miR-499a-5p. 25 Similarly, the inhibitory roles of various miRNAs in tumorigenesis of NSCLC have been reported in previous studies. Meng et al showed that miR-377 plays an important role in the tumorigenesis of NSCLC by targeting astrocyte elevated gene-1, and may be a potential therapeutic target for lung cancer.…”

“… 23 Among them, miR-499a-5p, has been shown to play a key role in cardiomyogenic differentiation of bone marrow-derived mesenchymal stem cells and has inhibitory effects on the proliferation and differentiation of osteosarcoma. 24 , 25 However, there is currently no data regarding the functions of miR-499a-5p in NSCLC. In this study, we evaluated the role of miR-499a-5p in the tumorigenesis of NSCLC, as well as the underlying molecular mechanisms.…”

The TGFβ-miR-499a-SHKBP1 pathway induces resistance to EGFR inhibitors in osteosarcoma cancer stem cell-like cells

“…Accumulated studies uncovered that miR-499a was decreased in several cancers, including pancreatic cancer [32], hepatocellular carcinoma [33] and oral squamous cell carcinoma [34], functioning as the tumor suppressor. In OS, it was found inhibiting OS cell proliferation [35], however, the biological function and underlying mechanisms of miR-499a in OSCs was unclear. In this study, by characterizing the down-stream mechanisms of TGFβ-induced EMT in OS, we found that miR-499a was significantly reduced upon TGFβ treatment.…”

<p>MiR-499a-5p Inhibits Pr5/4/20 publish l Cancer Cells via Targeting eIF4E</p>

“…16 MiR-499a-5p has gained increasing attention in cancer research because of its anti-tumor action. The aberrant downregulation of miR-499a-5p expression has been identified in oral squamous cell carcinoma, 17 osteosarcoma, 12 and lung adenocarcinoma; 13 however, little is known regarding its expression in CC. Here, in this study, we firstly determined the expression level of miR-499a-5p in CC tissues and cell lines by qRT-PCR and found that miR-499a-5p was significantly downregulated in CC tissues and cells.…”

“…For instance, Liu et al found that the overexpression of miR-499a-5p repressed proliferation and differentiation of osteosarcoma cells by negatively regulating its target gene protein phosphatase 1D (PPM1D) through modulation of Akt/synthase kinase 3β (GSK-3β) signaling. 12 Additionally, it has been reported that miR-499a-5p promoted lung cancer cell proliferation, migration, and epithelial-mesenchymal transition (EMT) in vitro and enhanced tumor growth in vivo. 13 However, the expression of miR-499a-5p in CC tissues remains unclear, and whether it modulated the radiosensitivity of CC cells is still unknown.…”