Journal of Advanced Research (Mar 2022)
The prognostic miR-532-5p-correlated ceRNA-mediated lipid droplet accumulation drives nodal metastasis of cervical cancer
Abstract
Introduction: The prognosis for cervical cancer (CC) patients with lymph node metastasis (LNM) is extremely poor. Lipid droplets (LDs) have a pivotal role in promoting tumor metastasis. The crosstalk mechanism between LDs and LNM modulated in CC remains largely unknown. Objectives: This study aimed to construct a miRNA-dependent progonostic model for CC patients and investigate whether miR-532-5p has a biological impact on LNM by regualting LDs accumulation. Methods: LASSO-Cox regression was applied to establish a prognostic prediction model. miR-532-5p had the lowest P-value in RNA expression (P < 0.001) and prognostic prediction (P < 0.0001) and was selected for further study. The functional role of the prognostic miR-532-5p-correlated competing endogenous RNA (ceRNA) network was investigated to clarify the crosstalk between LDs and LNM. The underlying mechanism was determined using site-directed mutagenesis, dual luciferase reporter assays, RNA immunoprecipitation assays, and rescue experiments. A xenograft LNM model was established to evaluate the effect of miR-532-5p and orlistat combination therapy on tumor growth and LNM. Results: A novel 5-miRNAs prognostic signature was constructed to better predict the prognosis of CC patient. Further study demonstrated that miR-532-5p inhibited epithelial-mesenchymal transition and lymphangiogenesis by regulating LDs accumulation. Interestingly, we also found that LDs accumulation promoted cell metastasis in vitro. Mechanistically, we demonstrated a miR-532-5p-correlated ceRNA network in which LINC01410 was bound directly to miR-532-5p and effectively functioned as miR-532-5p sponge to disinhibit its target gene-fatty acid synthase (FASN). Combined therapy with miR-532-5p and FASN inhibitor-orlistat further inhibited tumor growth and LNM in vivo. Conclusion: Our findings highlight a LD accumulation-dependent mechanism of miR-532-5p-modulated LNM and support treatment with miR-532-5p/orlistat as novel strategy for treating patients with LNM in CC.