The downregulation of ANGPTL4 inhibits the migration and proliferation of tongue squamous cell carcinoma

• Provides the expression and function of ANGPTL4 in tongue squamous cell carcinoma (TSCC) and the relationship between ANGPTL4 and MVD.
• ANGPTL4 expression was associated with tumor stage, lymph node metastasis and MVD expression.
• High levels of ANGPTL4 expression were closely associated with poor survival time.
• Suppressing ANGPTL4 resulted in the inhibition of cell proliferation and migration, but neither invasion nor cisplatin resistance was significantly affected.
• ANGPTL4 may serve as a novel biomarker and therapeutic target for TSCC.

ObjectiveTongue squamous cell carcinoma (TSCC) is the most common malignant cancer in the oral cavity, with a high rate of metastasis to the neck lymphoid node. Angiopoietin-like protein 4 (ANGPTL4) and microvessel density (MVD) may be novel indicators for tumor metastasis. The aim of the present study was to investigate the expression and function of ANGPTL4 in TSCC and the relationship between ANGPTL4 and MVD.MethodsThe expression levels of ANGPTL4 and MVD (CD34) were analyzed in 65 TSCC specimens and the adjacent non-cancerous tissues using immunohistochemistry (IHC). siRNA was delivered into TSCCA cells to downregulate ANGPTL4 expression. Subsequently, validation with real-time RT-PCR and western blot analyses was performed to analyze ANGPTL4 expression levels. In addition, a proliferation assay, migration and invasion assays were carried out.ResultsANGPTL4 expression was associated with tumor stage, lymph node metastasis and MVD expression. Cox regression analysis showed that high levels of ANGPTL4 expression were closely associated with poor survival time. In vitro analyses using qRT-PCR and western blot confirmed that ANGPTL4 was successfully inhibited in TSCCA cells. Suppressing ANGPTL4 resulted in the inhibition of cell proliferation and migration, but neither invasion nor cisplatin resistance was significantly affected.ConclusionHigh expression levels of ANGPTL4 are associated with the T stage, lymphatic metastasis, angiogenesis and poor overall survival in TSCC patients. The downregulation of ANGPTL4 inhibits the migration and proliferation of cells in TSCC. Taken together, ANGPTL4 may serve as a novel biomarker and therapeutic target for TSCC.