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.
Keywords: ACC1, Acetyl-CoA carboxylase 1; ACOX1, Acyl-CoA oxidase 1; ATCC, The American Type Culture Collection; BMI, Body mass index; CC, Cervical cancer; CPAT, The coding potential assessment tool; CPT1A, Carnitine palmitoyltransferase-1A; Cervical cancer; CircRNAs, circular RNAs; DFS, Disease free survival; EMT, Epithelial-mesenchymal transition; ES, enrichment score; FA, Fatty acid; FASN; FASN, Fatty acid synthase; GEPIA, The Gene Expression Profiling Interactive Analysis; GSEA, Gene set enrichment analysis; HE, Hematoxylin-eosin; HLECs, Human lymphatic endothelial cells; IHC, immunohistochemistry; ISH, In situ hybridization; LASSO, The least absolute shrinkage and selection operator; LDs, Lipid droplets; LINC01410, Long non-coding RNA 01410; LNM, lymph node metastasis; Lipid droplet; LncRNAs, Long noncoding RNAs; Lymph node metastasis; MES, Maximum enrichment score; MREs, MiRNA response elements; Mfe, The minimum free energy; NCF2, Neutrophil cytosolic factor 2; OS, Overall survival; PLIN2, Perilipin 2; PLs, Phospholipids; RIP, RNA immunoprecipitation; ROC, The receiver operating characteristic; SNR, signal-to-noise ratio; STR, short tandem repeat; TCGA, The Cancer Genome Atlas; TGs, Triglycerides; ceRNA, Competing endogenous RNA; miRNA prognostic model; miRNAs, MicroRNAs; ncRNAs, Noncoding RNAs.
© 2022 The Authors. Published by Elsevier B.V. on behalf of Cairo University.