ABSTRACT
Abstract Objectives Nasopharyngeal Carcinoma (NPC) is a common malignant tumor of nasopharyngeal mucosal epithelium in clinical practice. Radiotherapy and chemotherapy are the main treatment methods at present, but the therapeutic effect is still unsatisfactory. Studies have shown that exosomes and microRNAs (miRNAs) play an important role in the development of cancer. Therefore, this study aimed to investigate the effects of NPC derived exosomes on NPC and their molecular mechanisms. Methods Serum was collected from healthy subjects, Epstein-Barr Virus (EBV) infected patients and NPC patients (n = 9 group) and exosomes were extracted separately. High-throughput sequencing of exosomes was performed to screen differentially expressed miRNAs. The function of the screened miRNA was identified by treating NPC cells with exosomes. The target gene of miRNA was identified using the dual-luciferase assay. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) was used to determine the levels of miR-99a-5p and Bromodomain Adjacent Tozinc finger domain protein 2A (BAZ2A). Cell Counting Kit-8 assay, flow cytometry, and wound healing assay were utilized to detect cell viability, cell cycle and apoptosis, and migration ability. The protein levels were evaluated by Western blot. Results MiR-99a-5p was identified as the most significant differentially expressed miRNA in exosomes (p< 0.05). The proliferation and migration of NPC cells were extremely facilitated by exosomes, accompanied by the suppressed apoptosis, upregulated BAZ2A, Monocyte Chemotactic Protein-1 (MCP1), and Vascular Endothelial Growth Factor A (VEGFA), and downregulation of Interleukin (IL)-1β and Nuclear Transcription Factor-κB (NF-κB) (p< 0.05). BAZ2A was a target gene of miR-99a-5p. Furthermore, the regulatory effect of exosomes on the proliferation, migration, and apoptosis was significantly abolished by overexpression of miR-99a-5p or downregulation of BAZ2A (p< 0.05). Conclusion NPC derived exosomes facilitated the proliferation and migration of NPC through regulating the miR-99a-5p/BAZ2A axis.
ABSTRACT
AIM:To study the effect of diallyl trisulfide (DATS) on experimental corneal neovascularization (CNV) in rats induced by corneal suture and detect the expression of vascular endothelial growth factor (VEGF) and p-AKT in rats cornea.METHODS:The rat model of corneal neovascularization (CNV) was induced by corneal suture.Rats were randomly divided into Group A:physiological saline control group containing DMSO (10 rats);Group B:25μmol/L DATS treatment group (10 rats);Group C:50μmol/L DATS treatment group (10 rats);Group D:100μmol/L DATS treatment group (10 rats);Group E:200μmol/L DATS treatment group (10 rats).The occurrence and development of CNV were observed by slit-lamp microscope at 7d after suture,and the area of CNV were calculated.Two weeks later,HE staining was used to observe the pathological organization form of each cornea,and RT-PCR and Western blot were used to detect the expression of VEGF mRNA and protein expression of VEGF and p-AKT between each groups.RESULTS:The blood vessel area of Group C,D and E was compared with that of Group A,the difference was statistically significant (P＜0.05);HE slice showed corneal edema,angiogenesis and inflammation infiltration situation gradually reduced comparing with the Group A,with the increase of concentration of DATS.RT-PCR showed the expression of VEGF mRNA in Group B,C,D,and E decreased compared with the Group A,and the difference was statistically significant (P＜0.05).Western-blot showed that the expressions of VEGF and p-AKT in Group B,C,D and E decreased gradually compared with those in Group A,and the difference was statistically significant (P＜0.05).CONCLUSION:DATS can inhibit corneal neovascularization of the rats induced by suture.Its mechanism may be associated with suppression of VEGF secretion,down-regulation of VEGF and inactivation of p-AKT.