Comparative study of rabbit VX2 tumor angiogenesis in fatty liver and normal liver and correlation with contrast-enhanced ultrasound quantitative parameters

Abstract

Objective To comparative analysis the rabbit VX2 tumors angiogenesis in fatty liver and normal liver,and investigate the correlation of contrast-enhanced ultrasound (CEUS) parameters and their angiogenesis.Methods Rabbit models of fatty liver and normal liver with implanted VX2 tumors were established.Two groups of hepatic backgrounds and VX2 tumors were analyzed by QontraXt quantitative software of CEUS.The expression level of tumor microvascular density (MVD) and vascular endothelial growth factor (VEGF) were detected with immunohistochemical techniques and real-time fluorescence quantitative PCR (FQ-PCR).Results ①No significant difference was found in MVD,VEGF protein and gene expression between VX2 tumors in normal liver and fatty liver.The expression of VEGF gene in fatty liver parenchyma were lower than normal liver parenchyma (P ＜0.05).②There was positive correlation between MVD and peak intensity (r =0.494,P ＜0.05; r =0.591,P ＜0.01) both in fatty liver and normal liver VX2 tumors.The expression of VEGF protein were not correlated with TIC parameters (all P ＞ 0.05).③The MVD had positive correlation with expression of VEGF protein in fatty liver and normal liver VX2 tumors (r =0.508,P ＜0.05; r =0.570,P ＜0.01).Conclusions The expression of MVD and VEGF had no significant difference between fatty liver and normal liver VX2 tumors.The peak intensity of VX2 tumors CEUS had positive correlation with MVD both in fatty liver and normal liver,which can indirectly reflect MVD expression level and help to evaluate tumor angiogenesis. Key words: Ultrasonography; Microbubbles; Liver neoplasms, experimental; Fatty liver; Neovascularization, pathologic