Expression of plasma vascular endothelial growth factor in patients with hepatocellular carcinoma and effect of transcatheter arterial chemoembolization therapy on plasma vascular endothelial growth factor level

AIM: To investigate the expression level of plasma vascularendothelial growth factor (P-VEGF) in patients withhepatocellular carcinoma (HCC) and its relationship withthe clinicopathologic characteristics, and to examine thechanges of P-VEGF in the course of transcatheter arterialchemoembolization (TACE).METHODS: Peripheral blood samples were taken from 45HCC patients before and 1, 3, 7 d, and 1 mo after TACE.Plasma VEGF level was measured with the quantitativesandwich enzyme-linked immunosorbent assay (ELISA).Twenty patients with benign liver lesions and 17 healthycontrol subjects were also included in this study.RESULTS: Plasma VEGF levels in HCC patients weresignificantly elevated as compared to those in patients withbenign liver lesions (P = 0.006) and in the normal controls(P = 0.003). Significant differences were observed whenP-VEGF was categorized by tumor size (P = 0.006), portalvein thrombosis (P= 0.011), distant metastasis (P= 0.017),arterial-portal vein shunting (P = 0.026), and InternationalUnion Against Cancer (UICC) TNM stage (P = 0.044). Therewas no correlation between plasma level of VEGF and thelevel of alpha fetoprotein (^-FP) (r = 0.068, P = 0.658) andweakly correlated with the number of platelets (r = 0.312,P = 0.038). P-VEGF levels increased significantly andreached the peak value on the first day after TACE, and thendecreased gradually. The change rate of P-VEGF concentration(one month post-TACE/pre-TACExl00%) was correlatedwith the retention rate of lipiodol oil (rs = 0.494, P= 0.001)and the tumor volume change (r s = 0.340, P = 0.034).The patients who achieved a partial or complete responseto TACE therapy showed significantly less pre-treatmentP-VEGF than those nonresponders (P = 0.025). A high pre-therapeutic P-VEGF level was associated with poor responseto treatment (P = 0.018).CONCLUSION: A high pre-treatment P-VEGF level is auseful marker for tumor nroeression, esBeciallv for vascularinvasion. TACE increases the level of P-VEGF onlytemporarily which may be associated with tumor ischemia.P-VEGF may be useful in predicting treatment response,monitoring disease course after TACE and judging the effectof different TACE regimens.

Influential factors and formation of extrahepatic collateral artery in unresectable hepatocellular carcinoma

AIM: To analyze the influence factors and formation of extrahepatic collateral arteries (ECAs) in unresectable hepatocellular carcinoma (HCC) with or without chemoembolization.METHODS: Detailed histories of 35 patients with 39 ECAs of HCC and images including computerized tomography scan, digital subtraction angiography were reviewed carefully to identify ECAs of HCC, ECAs arising from, and anatomic location of tumors in liver. Tumor sizes were measured, and relations of EC As with times of chemoembolization, tumor size, and the anatomic tumor location were analyzed. Complications were observed after chemoembolization through ECAs of HCC with different techniques. RESULTS: Influence factors of formation of ECAs of HCC included the times of repeated chemoembolization, thelocation of tumors in liver, the tumor size and the types of chemoembolization. ECAs in HCC appeared after 3-4 times of chemoembolization (17.9%), but a higher frequency of ECAs occurred after 5-6 times of chemoembolization (56.4%). ECAs presented easily in peripheral areas (71.8%) of liver abutting to the anterior, posterior abdominal walls, the top right of diaphragm and right kidney.ECAs also occurred easily after complete obstruction of the trunk arteries supplying HCCs or the branches of proper hepatic arteries. Extrahepatic collaterals of HCC originated from right internal thoracic (mammary) artery (RITA, 5.1%), right intercostal artery (RICA, 7.7%), left gastric artery (LGA, 12.8%), right inferior phrenic artery (RIPA, 38.5%),omental artery (OTA, 2.6%), superior mesenteric artery (SMA, 23.1%), and right adrenal and renal capsule artery (RARCA, 10.3%), respectively. The complications after chemoembolization attributed to no super selective cathet erization.CONCLUSION: The formation of ECAs in unresectable HCCis obviously correlated with multiple chemoembolization,tumor size, types of chemoembolization, anatomic locationof tumors. Extrahepatic collaterals in HCC are corresponding to the tumor locations in liver.

Vascular endothelial growth factor antisense oligodeoxynucleotides with lipiodol in arterial embolization of liver cancer in rats

AIM:Transcatheter arterial embolization (TAE) of the hepatic artery has been accepted as an effective treatment for unresectable hepatocellular carcinoma (HCC). However,embolized vessel recanalization and collateral circulation formation are the main factors of HCC growth and recurrence and metastasis alter TAE. Vascular endothelial growth factor (VEGF) plays an important role in tumor angiogenesis.This study was to explore the inhibitory effect of VEGF antisense oligodeoxynucleotides (ODNs) on VEGF expression in cultured Walker-256 cells and to observe the anti-tumor effect of intra-arterial infusion of antisense ODNs mixed with lipiodol on rat liver cancer.METHODS: VEGF antisense ODNs and sense ODNs were added to the media of non-serum cultured Walker-256 cells.Forty-eight hours later, VEGF concentrations of supernatants were detected by EUSA. Endothelial cell line ECV-304 cells were cultured in the supernatants. Seventy-two hours later,growth of ECV-304 cells was analyzed by NTT method. Thirty Walker-256 cell implanted rat liver tumor models were divided into 3 groups.0.2 mL lipiodol (LP group, n=10), 3OD antisense ODNs mixed with 0.2 mL lipiodol (LP+ODNs group, n=10) and 0.2 mL normal saline (control group, n=10) were infused into the hepatic artery. Volumes of tumors were measured by MRI before and 7 d alter the treatment.VEGF mRNA in cancerous and peri-cancerous tissues was detected by RT-PCR. Microvessel density (MVD) and VEGF expression were observed by immunohistochemistry.RESULTS: Antisense ODNs inhibited Walker-256 cells' VEGF expression, The tumor growth rate was significantly lower in LP+ODNs group than that in LP and control groups (140.1±33.8%, 177.9±64.9% and 403.9±69.4% respectively, F=60.019,P<0.01).VEGF mRNAs in cancerous and peri-cancerous tissues were expressed highest in LP group and lowest in LP+ODNs group. The VEGF positive rates showed no significant difference among LP, control and LP+ODNs groups (90%,70% and 50%, H=3.731, P>0.05).The MVD in LP+ODNs group (53.1±18.4) was significantly less than that in control group (73.2±20.4) and LP group(80.3±18.5) (F=5.44, P<0.05).CONCLUSION: VEGF antisense ODNs can inhibit VEGF expression of Walker-256 cells.It may be an antiangiogenesis therapy agent for malignant tumors. VEGF antisense ODNs mixed with lipiodol embolizing liver cancer is better in inhibiting liver cancer growth, VEGF expression and microvessel density than lipiodol alone.