ABSTRACT
BACKGROUND: Lung adenocarcinoma (LUAD) is the most popular type of lung cancer. Sulfotanshinone IIA sodium (STS IIA) has been proven to have an anticancer effect. However, its role in LUAD and its underlying mechanism remain unclear. OBJECTIVE: To investigate the role and mechanism of STS IIA in LUAD angiogenesis. METHODS: The mRNA levels of genes, including forkhead box O3 (FOXO3) and chemokine C-X-C motif ligand 1 (CXCL1), were detected by qRT-PCR. The levels of proteins, including FOXO3, CXCL1, and vascular endothelial growth factor (VEGF), were measured by Western blot. The proliferation and angiogenesis of human umbilical vein endothelial cells (HUVECs) were detected by the EdU assay and the tubule formation assay, respectively. The binding relationship between FOXO3 and CXCL1 was detected by dual-luciferase reporter assay. RESULTS: Our results illustrated that different concentrations of STS IIA inhibited the proliferation and angiogenesis of HUVECs. FOXO3 regulated the proliferation and angiogenesis of HUVECs inhibited by STS â ¡A via targeting CXCL1. Subsequently, we proved that exogenous CXCL1 alleviated the inhibition of proliferation and angiogenesis of HUVECs regulated by STS IIA via activating the STAT3/VEGF pathway. Finally, we found that STS IIA inhibited the angiogenesis of lung adenocarcinoma though FOXO3 to inhibit the CXCL1/STAT3/VEGF pathway. CONCLUSION: Our study finally elucidated the underlying molecular mechanism by which STS â ¡A inhibits LUAD angiogenesis.
Subject(s)
Adenocarcinoma of Lung , Vascular Endothelial Growth Factor A , Humans , Vascular Endothelial Growth Factor A/metabolism , Signal Transduction , Cell Proliferation , Angiogenesis , Human Umbilical Vein Endothelial Cells , Adenocarcinoma of Lung/metabolism , Neovascularization, Pathologic , Chemokine CXCL1/metabolism , Chemokine CXCL1/pharmacology , Forkhead Box Protein O3/metabolism , STAT3 Transcription Factor/metabolism , STAT3 Transcription Factor/pharmacologyABSTRACT
CONTEXT: Sodium tanshinone IIA sulphate (STS) is a product originated from Salvia miltiorrhiza Bunge [Lamiaceae], which exerts an antitumour effect. However, the role of STS on lung adenocarcinoma (LUAD) remains unexplored. OBJECTIVE: Our study explores the effect and mechanism of STS against LUAD. MATERIALS AND METHODS: LUAD cells were treated with 100 µM STS for 24 h and control group cells were cultured under normal medium conditions. Functionally, the viability, migration, invasion and angiogenesis of LUAD cells were examined by MTT, wound healing, transwell and tube formation assay, respectively. Moreover, cells were transvected with different transfection plasmids. Dual luciferase reporter and RNA immunoprecipitation (RIP) assays were used to verify the relationship between miR-874 and eEF-2K. RESULTS: STS significantly decreased the viability (40-50% reduction), migration (migration rate of A549 cells from 0.67 to 0.28, H1299 cells from 0.71 to 0.41), invasion (invasion numbers of A549 cells from 172 to 55, H1299 cells from 188 to 35) and angiogenesis (80-90% reduction) of LUAD cells. Downregulation of miR-874 partially abolished the antitumour effect of STS. EEF-2K was identified to be the target of miR-874, and its downregulation markedly abolished the effects of miR-874 downregulation on tumourigenesis of LUAD. Moreover, silencing of TG2 abrogated eEF-2K-induced progression of LUAD. DISCUSSION AND CONCLUSIONS: STS attenuated the tumourigenesis of LUAD through the mediation of the miR-874/eEF-2K/TG2 axis. STS is a promising drug to fight against lung cancer, which might effectively reverse drug resistance when combined with classical anticancer drugs.
