Efficacy of transcatheter arterial chemoembolization combined with sorafenib in inhibiting tumor angiogenesis in a rabbit VX2 liver cancer model

Background:The aim of this study was to investigate the effects of transcatheter arterial chemoembolization(TACE)combined with sorafenib on tumor angiogenesis.Materials and methods:Thirty New Zealand rabbit VX2 liver cancer model animals were divided into five groups,which received either normal saline(A),TACE(B),sorafenib(C),sorafenib followed by TACE(D),or TACE followed by sorafenib(E).Serum vascular endothelial growth factor(VEGF)levels were measured before and after TACE via ELISA.Immunohistochemistry for CD34 was performed to evaluate microvessel density(MVD),and ultrasonography was used to access tumor volume.Results:VEGF levels declined in group C but increased significantly on the 3 rd post-operative day in groups B,D,and E.Levels decreased after the 7 th post-operative day.Peak levels were significantly lower in group D than in groups B and E.On the 14 th post-operative day,VEGF levels were the lowest in group C,followed by those in groups D and B.MVD was the lowest in group C followed by that in group D and E,and was the highest in group B.Group D had the smallest tumor volume.HE staining of tumor tissues from group C showed apoptosis in a scattered patchy pattern,whereas in groups B,D,and E,large areas of tumor cell necrosis were visible.Conclusion:TACE can up-regulate serum VEGF levels,which in turn accelerates the formation of new blood vessels.Thus,TACE combined with sorafenib inhibits VEGF and angiogenesis,and pre-operative administration of sorafenib has a more superior anti-angiogenic effect than post-operative administration.

Preparation and Characterization of LiTaO_3 Films Derived by an Improved Sol-Gel Process

In this paper, an improved sol-gel method was suggested to obtain high-concentration LiTaO3 precursor solution for simplified experimental conditions and thicker films, by mixing lithium acetate and tantalum ethoxide in a 1, 2-Propylene glycol solution. Compared to traditional methods, the process was done without weak acidic solution and absolute dry experimental condition. Results of a comparative study of LiTaO3 thin films derived by the improved sol-gel process and a traditional process using 2-methoxy ethanol as solvent were presented. Nano-crystalline LiTaO3 films with rhombohedral structures were formed in both methods after annealing at 650℃ for 5 min. The thickness of each LiTaO3 layer coated onto the substrate increased from 25 nm to 110 nm when 2-methoxy ethanol was replaced by 1, 2-Propylene glycol. LiTaO3 films with a stronger preferential orientation were obtained in 1, 2-Propylene glycol due to its higher boiling point and slower volatilization rate. On the other hand, the diffraction peak intensity of LiTaO3 thin films prepared using 1, 2-Propylene glycol was weaker than that of the films prepared using 2-methoxy ethanol due to decreased times of annealing.