ABSTRACT
BACKGROUND: Circular RNA (circRNA) has been shown to be closely associated with cancer progression, including gastric cancer (GC). However, the function of circ_0004104 in GC progression has not been clarified. AIMS: The purpose of this study was to explore the role of circ_0004104 in GC progression. METHODS: The expression levels of circ_0004104, miR-539-3p, and ring finger protein 2 (RNF2) were assessed using quantitative real-time polymerase chain reaction. Cell proliferation was measured by 3-(4,5-dimethyl-2 thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, and cell migration and invasion were detected using transwell assay. The levels of glutamine, glutamate, and α-ketoglutarate were determined to evaluate the glutaminolysis of cells, and the protein levels of glutaminolysis-related markers and RNF2 were detected using western blot analysis. Furthermore, Dual-Luciferase Reporter Assay was employed to assess the interaction between miR-539-3p and circ_0004104 or RNF2. Animal experiments were carried out to evaluate the effect of circ_0004104 silencing on GC tumor growth in vivo. RESULTS: Circ_0004104 was upregulated in GC, and its knockdown repressed the proliferation, metastasis, and glutaminolysis of GC cells in vitro and reduced GC tumor growth in vivo. Furthermore, we discovered that circ_0004104 could sponge miR-539-3p and miR-539-3p could target RNF2. The rescue experiments suggested that miR-539-3p inhibitor could reverse the suppressive effect of circ_0004104 silencing on GC progression, and RNF2 overexpression also reversed the inhibition effect of miR-539-3p mimic on GC progression. CONCLUSION: Circ_0004104 accelerated GC progression via regulating the miR-539-3p/RNF2 axis, indicating that circ_0004104 might be a potential therapeutic target for GC.
Subject(s)
Exosomes/metabolism , MicroRNAs/metabolism , Polycomb Repressive Complex 1/metabolism , RNA, Circular/metabolism , Stomach Neoplasms/enzymology , Aged , Animals , Cell Line, Tumor , Cell Movement , Cell Proliferation , Disease Progression , Exosomes/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Mice, Inbred BALB C , Mice, Nude , MicroRNAs/genetics , Middle Aged , Neoplasm Invasiveness , Polycomb Repressive Complex 1/genetics , RNA, Circular/genetics , Signal Transduction , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Tumor BurdenABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Salvia miltiorrhiza Bge. as a traditional Asian medicinal plant, roots and rhizomes (Danshen) are used to treat chronic hepatitis and coronary heart disease. In recent years, the medicinal value of S. miltiorrhiza stems and leaves total phenolic acids extract (JF) similar to roots and rhizomes has received increasing attention. S. miltiorrhiza roots and rhizome tanshinone extract (DT) has a good anti-inflammatory effect. AIM OF THE STUDY: To explore the therapeutic effect and possible molecular mechanisms of JF and DT alone or in combination on dextran sulfate sodium (DSS)-induced colitis mice. MATERIALS AND METHODS: Colitis was induced by received 2% DSS in drinking water for 7 consecutive days. Then mice were administered orally for 7 days. Disease activity index (DAI) scores and body weight were recorded daily. After the end of the experiment, colon was removed, colon length was measured and histopathological analysis was performed. Inflammatory factors expression was determined by ELISA, its mRNA expression was detected by real-time quantitative PCR, and the expression of related proteins on TLR4/PI3K/AKT/mTOR signal was analyzed by Western blot. RESULTS: Treatment with JF and DT alone or in combination reduced DAI scores, increase body weight, improved colon shortening, and decreased colon histology scores. In addition, the expression level of inflammatory factors was inhibited. The combination of JF and DT had a better inhibitory effect on inflammatory factors compared to JF alone. We also found that DT alone and JF combined with DT inhibited TLR4/PI3K/AKT/mTOR signaling-related proteins expression levels (including TLR4, p-PI3K p110α/PI3K p110α, p-AKT (ser473)/AKT, mTOR, p-mTOR, NF-κB p65), showing an effective anti-inflammatory effect. CONCLUSIONS: We demonstrated for the first time that, JF and DT alone or in combination effectively ameliorated DSS-induced ulcerative colitis in mice, possibly by inhibiting the TLR4/PI3K/AKT/mTOR signaling pathway.
