Serum levels of angiogenic and anti-angiogenic factors: their prognostic relevance in locally advanced hepatocellular carcinoma

Vascular Endothelial Growth Factor Levels Difference among Hepatocellular Cancer Patients Based on Barcelona Clinic Liver Cancer Staging

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. It depends on angiogenesis for growth and metastasis. Vascular endothelial growth factor (VEGF), a growth factor for angiogenesis, is hoped to be a biomarker for the diagnosis of HCC and its development. AIM: The objective of the study is to determine the difference of VEGF levels among HCC patients based on barcelona clinic liver cancer (BCLC) staging. METHODS: A cross-sectional study was conducted at Haji Adam Malik General Hospital Medan, Indonesia between January and December 2018. Patients aged 18 years or older with HCC were enrolled using consecutive sampling method. Patients with cholangiocarcinoma, hemangioma, and liver metastasis were excluded from the study. The diagnosis of HCC was confirmed by triphasic computed tomography-scanning. Circulating VEGF levels were determined from serum specimen using Quantikine Human VEGF-enzyme-linked immunosorbent assay. All patients were grouped based on BCLC staging. Kruskal Wallis-H test was applied at 95% confidence interval. p < 0.05 was considered significant. RESULTS: Of 60 patients, 47 (78.3%) were male. Mean age of patients was 61.4 (SD11.7) years. Hepatitis B was the most common etiology (70.0%) of HCC. Based on BCLC staging, 25 (41.7%) patients were in stage C. Median VEGF level was 951.25 pg/mL. There was a statistically significant difference in VEGF levels (p = 0.006) where patients in Stage C (1,009.6 pg/mL) and D (1,189.7 pg/mL) had higher VEGF levels compared to those in Stage A (578 pg/mL). CONCLUSION: There was a statistically significant difference of VEGF levels among HCC patients based on BCLC staging.

Utility of serum neuropilin-1 and angiopoietin-2 as markers of hepatocellular carcinoma

This study aimed to assess the diagnostic value of two serum angiogenetic markers neuropilin-1 (NRP-1) and angiopoietin-2 (ANG-2) in patients with hepatocellular carcinoma (HCC) and their relation to tumor characteristics. 149 subjects were recruited and divided into 50 patients with recently diagnosed HCC, 49 patients with cirrhosis on top of hepatitis C virus infection, and 50 healthy subjects. Serum NRP-1 and ANG-2 were estimated by ELISA. Alpha-fetoprotein (AFP) levels were measured using fluorescence immunoassay. Serum NRP-1 and ANG-2 levels were significantly higher in patients with HCC (2221.8±1056.6 pg/mL and 3018.5±841.4 pg/mL) than healthy subjects (219.3±61.8 pg/mL and 2007.7±904.8 pg/mL) and patients with cirrhosis (1108.9±526.6 pg/mL and 2179.1±599.2 pg/mL), respectively. In multivariate logistic regression analysis, NRP-1 and AFP were the only independent factors of HCC development and correlated positively with each other (r=0.781, p<0.001). Receiver operating characteristic curve analysis showed that the area under the curve (AUC) of NRP-1 was higher than that of ANG-2 in discriminating HCC from patients with cirrhosis (0.801 vs 0.748, p=0.250) and healthy subjects (0.992 vs 0.809, p<0.001). The AUC of NRP-1 was detected to be increased (0.994) when combined estimation with AFP was performed. Elevated serum NRP-1 and ANG-2 levels were detected in patients with HCC with tumor numbers >3, tumor size ≥5 cm, tumor stages B/C according to the Barcelona Clinic Liver Cancer staging system, vascular invasion, and distant metastasis. In conclusion, NRP-1 is a potential serological marker for HCC diagnosis and is better than ANG-2. It is feasible to be estimated in combination with AFP to enhance its diagnostic power. High serum NRP-1 and ANG-2 levels are associated with advanced HCC tumor characteristics.

The Angiopoietin/Tie2 Pathway in Hepatocellular Carcinoma

Due to the usually late diagnosis and lack of effective therapies, hepatocellular carcinoma (HCC), which poses a growing global health problem, is characterized by a poor prognosis. Angiogenesis plays an important role in HCC progression, and vascular endothelial growth factor (VEGF) and angiopoietins (Angs) are key drivers of HCC angiogenesis. VEGF-targeting strategies already represent an important component of today’s systemic treatment landscape of HCC, whereas targeting the Ang/Tie2 signaling pathway may harbor future potential in this context due to reported beneficial anticancer effects when targeting this pathway. In addition, a better understanding of the relation between Angs and HCC angiogenesis and progression may reveal their potential as predictive factors for post-treatment disease progression and prognosis. In this review, we give a comprehensive overview of the complex role of Ang/Tie2 signaling in HCC, pinpointing its potential value as biomarker and target for HCC treatments, aiding HCC diagnosis and therapy.

Clinical and prognostic significance of circulating levels of angiopoietin-1 and angiopoietin-2 in hepatocellular carcinoma

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play critical roles in angiogenesis in hepatocellular carcinoma (HCC). In addition, recent data suggest that Ang-1/Ang-2 are involved in regulating the immune response. The aim of our study was to explore the clinical prognostic significance of plasma Ang-1 and Ang-2 in HCC. We prospectively enrolled and collected data and blood samples from 767 HCC patients treated at MD Anderson Cancer Center between 2001 and 2014. Controls consisted of cirrhotic patients (n = 75) and healthy volunteers (n = 200). The cutoff value was the median level of each angiogenic factor. Overall survival (OS) was estimated by Kaplan–Meier curves and compared by the log-rank test. Higher plasma Ang-2 was significantly associated with advanced clinicopathologic features of advanced HCC and lower OS. Median OS was 61.8 months (95% confidence interval [CI], 45.1–78.5 months) for low Ang-2 compared with 28.5 months (95% CI, 24.8–32.1 months) for high Ang-2 (p < 0.001). In contrast, higher Ang-1 was associated with longer OS. Median OS was 37.2 months (95% CI, 31.0–43.4 months) for high Ang-1 compared with 26.2 months (95% CI, 22.2–30.3 months) for those with low Ang-1 (p = 0.043). In conclusion, our findings indicate that plasma Ang-1 and Ang-2 levels are potential diagnostic and prognostic biomarkers in HCC.

Angiopoietin-2 (Ang-2) is a useful serum tumor marker for liver cancer in the Chinese population

BACKGROUND

We estimated the diagnostic and prognostic value of serum angiopoietin-2 (Ang-2) in liver cancer patients.

METHODS

Tissue Ang-2 was measured using immunohistochemistry (IHC). Cell localization of Ang-2 was tested using immunofluorescence (IF). Cell viability and apoptosis were evaluated using MTT and caspase3/7 assays, respectively. Colony-formation was measured using a soft agar assay. Serum Ang-2 was examined using enzyme-linked immunosorbent assay (ELISA) and Western blotting.

RESULTS

Ang-2 was up-regulated in liver cancer compared to the levels in normal tissues. Serum Ang-2 concentrations were much higher in liver cancer patients than in healthy individuals and those with chronic liver disease (CLD). Inhibitions of Ang-2 using specific shRNA decreased cell proliferation. Serum Ang-2 decreased significantly after surgery. Serum Ang-2 was positively correlated with serum alpha-fetoprotein (AFP; R=0.375, P=0.005). Receiver operating characteristic (ROC) curves suggested that serum Ang-2 could be used with relatively high sensitivity and specificity in differentiating liver cancer patients from CLD patients or healthy controls, with corresponding AUC values of 0.742 and 0.924, respectively. Serum Ang-2 was negatively correlated with overall survival. Subgroup analysis also showed that Ang-2 retained its prognostic value in overall survival prediction in different risk subgroups.

CONCLUSION

Serum Ang-2 may be a useful tumor marker in predicting liver cancer prognosis.

Diagnostic value of combined detection of angiopoietin-2 and Golgi protein 73 in primary liver cancer

AIM: To detect the expression of circulating angiopoietin-2 (Ang-2) and Golgi protein 73 (GP73) in patients with primary liver cancer and to analyze their value in the diagnosis and differential diagnosis of primary liver cancer (PLC).

METHODS: The levels of circulating Ang-2 and GP73 expression were detected by ELISA in patients with PLC, acute hepatitis, chronic hepatitis, or liver cirrhosis. The expression of Ang-2 and GP73 in cancerous and surrounding noncancerous tissues was analyzed by immunohistochemistry and confirmed by Western blot.

RESULTS: Positive expression of hepatic GP73 and Ang-2 was characterized by the presence of brown granules in the cytoplasm or cytomembrane. Hepatic GP73 and Ang-2 expression was significantly higher in cancerous tissue than in surrounding noncancerous tissue (P < 0.01). The levels of circulating Ang-2 and GP73 in PLC patients (40.8 ng/mL ± 3.5 ng/mL and 87.3 ng/mL ± 78.4 ng/mL, respectively) were significantly higher (P < 0.01) than those in normal subjects and patients with acute hepatitis, chronic hepatitis, or liver cirrhosis. There was a positive correlation between Ang-2 and GP73 (r = 0.987, P = 0.013). The area under the receiver operating curve (ROC) for the diagnosis of PLC was 0.915 for Ang-2 and 0.899 for GP73.

CONCLUSION: The overexpression of Ang-2 and GP73 is associated with HCC development and may be useful biomarkers for PLC diagnosis or differential diagnosis.

Repeated-measures implication of hepatocellular carcinoma biomarkers in living donor liver transplantation

Objective

Hepatocellular carcinoma (HCC) and its recurrence are major problems in living donor liver transplantation (LDLT). Several biomarkers have been used to investigate this event. We conducted a prospective controlled study to determine the activities of the basic fibroblast growth factor (FGF-2), survivin, Ki67, endostatin, and vascular endothelial growth factor (VEGF) in different conditions before, early after, and late after LDLT with and without HCC recurrence.

Methods

Fifty patients with virus-related HCC who underwent LDLT were enrolled in this 2-year cross-sectional study. During the study period, recurrent HCC was identified in 9 patients (study group, n = 9) and 41 patients (control group, n = 41) had no recurrence after LDLT. The mean time to HCC recurrence was 587.11 ± 398.64 days (range, 90–1352 days). Microvascular invasion (MVI) was found in 66.7% (6/9) of the recipients, as determined on pathological examination. The serum biomarkers were investigated by using enzyme-linked immunosorbent assay at the different LDLT stages.

Results

The serum levels of the biomarkers significantly correlated with LDLT and HCC recurrence in the repeated-measures analysis (F = 31.676, P = 0.000). Significant differences were observed in the effects of all biomarkers (F = 85.313, P = 0.000) and the time to HCC recurrence after LDLT (F = 3.178, P = 0.046). The biomarkers, ordered by the observed power of the test for HCC recurrence after LDLT, were FGF-2 (1.000) > survivin (0.999) > Ki67 (0.949) > endostatin (0.411) > VEGF (0.305).

Conclusions

Different biomarker activities may be implicated in the pathogenesis of HCC recurrence after LDLT. Oncogenes may not exist in the new graft but may still be present in the peripheral blood. The timing of HCC recurrence and impact of MVI in the explanted liver requires confirmation in larger studies with a longer follow-up.

Prognostic role of plasma vascular endothelial growth factor in patients with hepatocellular carcinoma undergoing liver transplantation

Vascular endothelial growth factor (VEGF) is pivotal in the development of hepatocellular carcinoma (HCC). Studies have demonstrated the prognostic value of circulating VEGF levels in patients undergoing liver resection or locoregional therapy (LRT) for HCC. We investigated the significance of preoperative plasma VEGF levels in patients with HCC undergoing liver transplantation (LT) at a Western transplant center. Pre-LT plasma VEGF levels were measured with an enzyme-linked immunoassay for 164 patients with HCC undergoing LT. The preoperative plasma VEGF level was correlated with clinicopathological variables and overall and recurrence-free post-LT survival. A higher pre-LT plasma VEGF level was significantly associated with pre-LT LRT (P = 0.01), multiple tumors (P = 0.02), a total tumor diameter ≥ 5 cm (P = 0.01), bilobar tumor distribution (P = 0.03), tumor vascular invasion (VI; P < 0.001), and HCC beyond the Milan criteria (P < 0.001). Patients with a plasma VEGF level > 44 pg/mL had significantly worse overall and disease-free survival than those with VEGF levels ≤ 44 pg/mL (P = 0.04 and P = 0.02, respectively). In a multivariate analysis, a plasma VEGF level > 44 pg/mL was independently associated with tumor VI (P < 0.001) and recurrence-free survival (hazard ratio = 2.12, 95% confidence interval = 1.08-4.14, P = 0.03). In conclusion, in patients with chronic end-stage liver disease and HCC, a pre-LT plasma VEGF level > 44 pg/mL may be a predictor of tumor VI and recurrence-free post-LT survival.

Angiopoietin 2 as a therapeutic target in hepatocellular carcinoma treatment: current perspectives

Hepatocellular carcinoma (HCC) is a hypervascular malignancy and is the third leading cause of death worldwide. The disease has multiple predisposing risk factors and limited treatment options. Although the precise mechanism(s) underlying HCC is unknown, several pathways have been implicated in its development. HCC is a vascular tumor and angiogenesis is believed to play an important role in its progression. Hypoxia is believed to increase the expression of vascular endothelial growth factor (VEGF) through the expression of the hypoxia-inducible factor-1α. VEGF and angiopoietin 2 (Ang2) are expressed on cancer cells, whereas angiopoietin 1 (Ang1) occurs predominantly in support cells of large blood cells as well as stromal, endothelial, and tumor cells. Ang2 is concomitantly an agonist and antagonist of angiopoietin 1 and is expressed during vascular remodeling. This prevents vascular stability and allows VEGF to stimulate endothelial cells. Ang2 is expressed along with growing blood vessels, destabilizing the vascular integrity. Inhibiting Ang2 can, on the other hand, promote vesicular stability and decrease angiogenesis. We discuss in this review angiopoietin as a therapeutic target alone or in combination with other therapies.

Clinical significance of serum and tumor tissue endostatin evaluation in operable non-small cell lung cancer

Endostatin, as the most potential antiangiogenic factor, is a naturally occurring fragment of collagen XVIII in bloodstream capable of inhibiting tumor growth and metastasis. This study was conducted to explore the clinical value of endostatin in serum and tumor tissue in patients with operable non-small cell lung cancer (NSCLC). ELISA and immunohistochemistry were applied to detect the expression of endostatin in serum and tumor tissue in 105 patient-matched operable NSCLC patients. The serum level of endostatin was significantly higher in NSCLC patients than healthy individuals (P=0.0018). Cases with poorer differentiation showed a higher endostatin serum level (P=0.008). There was no significant correlation between tumor tissue expression and clinical parameters, such as TNM stage, differentiation degree, histological type and lymph node invasion status. A stronger expression of endostain in tumor tissue was associated with a higher serum level (r=0.223). The univariate and multivariate analyses with Cox proportional hazards model for overall survival showed that tumor stage and node status were independent prognostic factors, whereas neither endostatin levels in serum nor in tumor tissue showed potential in predicting the long-term survival of operable NSCLC patients. In conclusion, the results observed in the present study did not support the prediction of overall survival in operable NSCLC based on the expression levels of endostatin in serum and tumor tissue.