miR-148a-3p regulates proliferation and apoptosis of idiopathic gingival fibroma by targeting NPTX1.

OBJECTIVE: Idiopathic gingival fibromatosis (IGF) is a rare heterogeneous disease that results in the progressive and diffuse hyperplasia of gingival tissues. MicroRNAs are implicated in the development and progression of various tumors. The present study aimed to explore the potential roles and mechanisms of miR-148a-3p in IGF. METHODS: Gingival fibroblasts (GFs) were transfected with miR-148a-3p mimics, miR-148a-3p inhibitors, or siNPTX1, and then, the proliferation and apoptosis of GFs and the expression of related genes were evaluated using Cell Counting Kit-8 assays, 5-ethynyl-2'-deoxyuridine assays, flow cytometry, reverse transcription-quantitative polymerase chain reaction, and western blot analysis, respectively. RESULTS: miR-148a-3p was highly expressed in GFs of IGF (IGF-GFs) as compared with normal GFs (N-GFs). Overexpression of miR-148a-3p promoted the proliferation and inhibited the apoptosis of N-GFs, whereas downregulation of miR-148a-3p had the opposite effect in IGF-GFs. Knockdown of NPTX1 reversed miR-148a-3p-mediated effects in IGF-GFs. Dual-luciferase reporter assay confirmed that NPTX1 is a direct target of miR-148a-3p. CONCLUSION: These findings identify that miR-148a-3p could regulate cell proliferation and apoptosis by targeting NPTX1, providing new insights for the further study of the molecular mechanism and treatment of IGF.

Exosomes derived from idiopathic gingival fibroma fibroblasts regulate gingival fibroblast proliferation and apoptosis.

OBJECTIVE: Exosomes have been proved to play an essential role in intercellular information transmission. However, few researches focused on exosomes derived from gingival fibroblasts (GFs) of IGF. The aim of this study is to investigate the effect of exosomes derived from GFs of IGF (IGF-GFs) on the proliferation and apoptosis of normal gingival fibroblasts (N-GFs). METHODS: Gingival fibroblasts were cultured and identified using immunocytochemistry. Exosomes were isolated with exosomes extraction kit and characterized by transmission electron microscopy (TEM) and flow cytometry. PKH67 labeling was further used to trace the intracellular distribution of the exosomes. And MTS assay was used to test the effective concentration and time course of IGF-GFs-derived exosomes. Furthermore, the expression of PCNA, Ki67, Bcl-2, and Bax in N-GFs was analyzed by qRT-PCR and Western blot. RESULTS: Exosomes were isolated from IGF-GFs; the identification of exosomes and gingival fibroblasts was successfully finished. Moreover, we found that N-GFs co-cultured with exosomes showed a great increase in PCNA and Bcl-2 levels, and a moderate increase in Ki67 levels. By contrast, the levels of Bax were significantly reduced. CONCLUSION: These results suggest that exosomes derived from idiopathic gingival fibroma fibroblasts are involved in the regulation of gingival fibroblast proliferation and apoptosis.