Circ_0027791 contributes to the growth and immune evasion of hepatocellular carcinoma via the miR-496/programmed cell death ligand 1 axis in an m6A-dependent manner.

Emerging evidence indicates the critical roles of circular RNAs in the development of multiple cancers, containing hepatocellular carcinoma (HCC). Herein, our present research reported the biological function and mechanism of circ_0027791 in HCC progression. Circ_0027791, microRNA-496 (miR-496), programmed cell death ligand 1 (PDL1), and methyltransferase-like 3 (METTL3) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, proliferation, invasion, and sphere formation ability were detected using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, 5-ethynyl-2'-deoxyuridine, transwell, and sphere formation assays. Macrophage polarization was detected using flow cytometry assay. To understand the role of circ_0027791 during the immune escape, HCC cells were cocultured with peripheral blood mononuclear cells or cytokine-induced killer (CIK) cells in vitro. A xenograft mouse model was applied to assess the function of circ_0027791 in vivo. After prediction using circinteractome and miRDB, the binding between miR-496 and circ_0027791 or PDL1 was validated based on a dual-luciferase reporter assay. Interaction between METTL3 and circ_0027791 was determined using methylated RNA immunoprecipitation (MeRIP)-qPCR, RIP-qPCR, and RNA pull-down assays. Circ_0027791, PDL1, and METTL3 expression were upregulated, and miR-496 was decreased in HCC patients and cells. Moreover, circ_0027791 knockdown might repress proliferation, invasion, sphere formation, M2 macrophage polarization, and antitumor immune response. Circ_0027791 knockdown repressed HCC tumor growth in vivo. In mechanism, circ_0027791 functioned as a sponge for miR-496 to increase PDL1 expression. In addition, METTL3 mediated the m6A methylation of circ_0027791 and stabilized its expression. METTL3-induced circ_0027791 facilitated HCC cell progression partly regulating the miR-496/PDL1 axis, which provided a new prognostic and therapeutic marker for HCC.

Oxymatrine extracted from Sophora flavescens inhibited cell growth and induced apoptosis in human osteosarcoma MG-63 cells in vitro.

Oxymatrine, one of the most active components of the ethanol extracts from Sophora flavescens, is known for its potent antitumor activity both in vitro and in vivo. However, the mechanism of its action in mediating the cell apoptosis remains elusive. In this study, we investigated the proliferation inhibitory and apoptotic activities of oxymatrine against human osteosarcoma MG-63 cells. The compound was found to markedly and dose-dependently inhibit the cell proliferation determined by 5-bromo-2-deoxyuridine incorporation. Oxymatrine also induced the cell apoptosis in a dose- and time-dependent manner as showed by the annexin V-FITC/PI double staining and TUNEL assay. Furthermore, a disruption of mitochondrial membrane potential and an up-regulation of cleaved caspases-3, and-9 and downregulation of Bax/Bcl-2 was evidenced in the oxymatrine-treated cells. These proteins have been known to play a pivotal role in the regulation of apoptosis. In conclusion, these observations indicate of the oxymatrine potential as an effective antitumor agent against osteosarcoma. Moreover, the compound appears to exert its anti-tumor action by stimulating the caspase-triggered signaling pathway.

[Clinical analysis of serum endothelin in type 2 diabetic patients with vascular complications].

OBJECTIVE: To explore the clinical significance of changes in urine microalbumin (UM) and endothelin (ET) in different courses of type 2 diabetes. METHODS: A clinical analyses of 30 type 2 diabetic patients with vascular complications (group A) was conducted in comparison with type 2 diabetic patients without vascular complications (group B) and patients with impaired glucose tolerance (IGT, group C). With 30 healthy subjects with family history of type 2 diabetes (group D) and 30 healthy subjects without such family history (group E) as controls, UM and ET were determined in all the subjects for a statistical analysis. RESULTS: Significant differences in UM content was noted between group A and the other 4 groups (P<0.05), while the content did not differ significantly between the latter 4 groups (P>0.05). ET content was significantly higher in group A than in the other 4 groups (P<0.01), and was the lowest in group E (P<0.01). CONCLUSIONS: Type 2 diabetic patients sustain extensively impaired endothelium function, which is exacerbated with the progression of the disease courses. Synchronized changes between vascular complications and impaired endothelium function indicates that vascular endothelial injury relates to vascular complications and the progression of diabetes.

[Relationship between serum vWF and PAF in type 2 diabetic patients and diabetic nephropathy].

OBJECTIVE: To observe the changes in urine albumin (UALB), von Willebrand factor (vWF) and platelet-activating factor (PAF) in different courses of type 2 diabetes. METHODS: Levels of UALB, vWF and PAF were determined in 30 type 2 diabetic nephropathy patients(group A), type 2 diabetic patients without DNP(group B, n=30), patients with impaired glucose tolerance (group C, n=30), the first-degree relatives of type 2 diabetic patients with normal glucose tolerance(group D, n=30) and 30 normal glucose tolerance subjects without family history of type 2 diabetes(group E). RESULTS: UALB and PAF contents were significantly higher in group A than in the other groups (P<0.01), while between the latter 4 groups, the contents showed no significant differences (P>0.05). Serum vWF level was significantly higher in group A than those in the other groups (P<0.05). CONCLUSIONS: Renal dysfunction and platelet activation are present in type 2 diabetes with microvascular complications, and the synchronized changes between renal dysfunction and platelet activation indicate the involvement of elevated PAF in vascular injury.