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[microRNA-1 gene delivery mediated by exosomes suppresses CAL-27 cell proliferation]
Bao-Qin Wu1,2, Chun-Hui Li1,2, Meng-Lian Zhang1
1Orofacial Reconstruction and Regeneration Laboratory, School of Stomatology of Southwest Medical University, Luzhou 646000, China.
Objectives:
This study aims to construct endogenous exosomes abundantly loaded with miR-1 and investigate the role of exosome-mediated microRNA-1 (miR-1) delivery on CAL-27 cell proliferation.
Methods:
Exosomes secreted by miR-1-overexpressing HEK293 cells (miR1-EXO) were purified via ultracentrifugation and subjected to transmission electron microscopy, nanoparticle analysis, Western blot analysis, and quantitative polymerase chain reaction (qPCR). CAL-27 cells were cocultured with exosomes secreted by HEK293 cells (CON-EXO) and miR1-EXO and equivalent phosphate buffer saline. The intracellular transport of exosomes was measured by using immunofluorescence, the expression of miR-1 and its target gene MET were investigated via qPCR, CAL-27 cell proliferation was measured through MTT assay, and cell cycle state was determined by applying flow cytometry.
Results:
Electron microscopy revealed that miR1-EXO and CON-EXO were spherical or cup-shaped with an average diameter of approximately 110 nm. The well-known exosome markers CD9, Tsg101, and Alix were enriched. The expression of miR-1 in miR1-EXO was higher than that in CON-EXO (285.80±14.33 vs 1.00±0.06, P<0.000 1). After coculture with CAL-27 cells, miR1-EXO was internalized and unloaded miR-1 into CAL-27 cells. After coculture with miR1-EXO, the expression of miR-1 in CAL-27 cells was upregulated, whereas that of MET, the target gene of miR-1, was suppressed and the proliferation of CAL-27 cells was inhibited significantly. Normal oral keratinocyte cell proliferation was negligibly affected after coculture with miR1-EXO.
Conclusions:
Exosomes secreted from miR1-EXO cells could load abundant miR-1. Exosomal miR-1 delivered into CAL-27 cells by using miR1-EXO suppressed the expression of MET mRNA and inhibited cell proliferation.
Insights
Engineered exosomes effectively deliver microRNA-1 (miR-1) to CAL-27 cells, suppressing proliferation by downregulating MET. This exosome-mediated miR-1 delivery shows potential for cancer therapy.
Area of Science:
- Cell Biology
- Molecular Biology
- Biotechnology
Background:
- Exosomes are crucial intercellular communicators.
- MicroRNA-1 (miR-1) plays a role in cell regulation.
- Targeting cancer cell proliferation is a key therapeutic goal.
Purpose of the Study:
- To construct engineered exosomes loaded with miR-1.
- To investigate exosome-mediated miR-1 delivery.
- To determine the effect of miR-1 delivery on CAL-27 cell proliferation.
Main Methods:
- HEK293 cells were engineered to overexpress miR-1.
- Exosomes (miR1-EXO) were purified and characterized.
- CAL-27 cells were co-cultured with miR1-EXO, and miR-1/MET expression, cell proliferation, and cell cycle were analyzed.
Main Results:
- miR1-EXO showed enriched exosome markers and significantly higher miR-1 expression.
- Internalization of miR1-EXO led to increased intracellular miR-1 and suppressed MET expression in CAL-27 cells.
- CAL-27 cell proliferation was significantly inhibited, with minimal effect on normal oral keratinocytes.
Conclusions:
- Engineered exosomes can efficiently load and deliver miR-1.
- Exosomal miR-1 delivery suppresses CAL-27 cell proliferation by targeting MET.
- This approach holds promise for oral cancer therapy.
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