The basic approach to target vascular endothelial growth factor (VEGF) expression in liver cancer under hypoxic condition.

尽管血管内皮生长因子（VEGF）在高血管肿瘤的生长中发挥作用，但其受体在血管内皮细胞上的旁分泌调节机制尚不清楚。本研究旨在探讨缺氧暴露的HepG2细胞释放的VEGF是否会改变人脐静脉内皮细胞（HUVECs）中两种不同受体KDR和fit-1， *的表达。将HepG2细胞在20% 02或1% 02中培养16小时，观察VEGF mRNA及其蛋白表达的诱导情况。将HepG2细胞条件培养基（CM）置于常压条件下，采用RT-PCR法检测vegf受体mRNA的表达。在缺氧胁迫下，HepG2细胞上调VEGF mRNA和VEGF的释放。缺氧- cm优先刺激huvec中fit-1 mRNA的表达，而不是KOR mRNA的表达。当缺氧暴露的HepG2细胞的VEGF释放被其反义寡脱氧核苷酸阻断时，缺氧- cm引起的内皮细胞fit-1 mRNA的上调仍然维持。这些结果表明缺氧暴露的肝癌细胞不仅可以产生VEGF，还可以通过不依赖于VEGF的机制进化出旁分泌诱导的fit-1。经导管肝动脉栓塞（TAE）治疗是低氧治疗肝细胞癌（HGC）的方法之一。因此，我们检测了肝细胞癌患者在治疗过程中接受TAE的血清中VEGE的水平。方法。本文对38例HCC合并丙型肝炎病毒阳性肝硬化患者进行了研究。经知情同意，于TAE前及TAE后1、3、7天采集外周血标本。测定血清中VEGF和另一种肝脏重塑因子肝细胞生长因子（HGF）的水平。测定血清支链氨基酸（BCAA）与酪氨酸（Tyr）的摩尔比（BTR），血清AST、ALT、LDH水平。结果。虽然AST、ALT、LDH *水平在TAE后1 d内达到峰值，但VEGF在TAE后7 d内明显升高。另一方面，在TAE过程中HGF和BTR水平没有明显变化。虽然TAE前HGF水平与VEGF水平有显著相关性，TAE后HGF水平与VEGF水平无显著相关性。这些数据共同表明，VEGF可能是在临床缺氧干预、TAE的反应中分泌的，独立于HGF或氨基酸代谢的情况。VEGF可能是肝肿瘤缺血的敏感标志物。少

Although vascular endothelial growth factor (VEGF) plays a role in growth of hypervascular tumors, mechanisms for paracrine regulation of its receptor expression on vascular endothelial cells remain unknown. This study aimed to investigate whether VEGF released from hypoxia-exposed HepG2 cells alter expression of two distinct receptors, KDR and fit-1, *n human umbilical venous endothelial cells (HUVECs). HepG2 cells Were cultured in 20% 02 or 1% 02 for 16 hours in order to examine induction of VEGF mRNA and its protein expression. Conditioned media of HepG2 cells (CM) were applied to HUVECs under normoxic conditions, and expression of mRNA for the VEGE receptors was determined by RT-PCR.In response to the hypoxic challenge, HepG2 cells upregulated VEGF mRNA and the release of VEGE.The hypoxia-CM stimulated preferentially the mRNA expression of fit-1, but not that of KOR in HUVECs. When the VEGF release from hypoxia-exposed HepG2 cells was blocked by its antisense-oligodeoxynucleotide, … More the endothelial fit-1 mRNA upregulation elicited by the hypoxia-CM was still maintained. These results suggest that hypoxia-exposed hepatic cancer cells can not only produce VEGF but also evolve paracrine induction of fit-1 through VEGE-independent mechanisms.Transcatheter hepatic arterial embolization (TAE) therapy is one of the hypoxic challenge to hepatocellular carcinoma (HGC). Therefore, we examined the level of VEGE in sera of patients with HCC who underwent TAE during the course of the treatment. Methods. Thirty eight patients with HCC and hepatitis C virus-positive cirrhosis were studied. Peripheral blood samples were taken before and 1, 3 7 days after TAE with informed consent. The serum levels of VEGF as well as hepatocyte growth factor (HGF), another hepatic remodeling factor, were measured. The molar ratio (BTR) of serum branched chain amino acid (BCAA) to tyrosine (Tyr), the serum levels of AST, ALT and LDH were also examined. Results. Although the level of AST, ALT and LDH *ched to the peak value within 1 day after TAE, VEGF increased significantly 7 days later. On the other hand, there were no significant alterations in the levels of HGF and BTR during the course of TAE.Although the level of HGF was significantly correlated with the level of VEGF before TAE, no remarkable correlation was observed after TAE.These data collectively suggest that VEGF may be secreted in response to clinical hypoxic intervention, TAE, independent of HGF or the condition of amino acid metabolism. VEGF may play a role as a sensitive marker for hepatic tumor ischemia. Less