VEGF Polymorphisms Related to Higher Serum Levels of Protein Identify Patients with Hepatocellular Carcinoma

Abstract

Hepatocellular carcinoma (HCC) is the most common primary neoplasia of the liver. Major risk factors for hepatocellular carcinoma include chronic liver diseases, carcinogenic agents, and genetic alterations as well as vascular endothelial growth factor (VEGF) involved in angiogenesis process. The aim of this study was to evaluate the association of VEGF-A (C936T and A1154G) with HCC and cirrhosis, in addition to serum levels of VEGF, clinical profile, lifestyle habits, and comorbidities. A total of 346 individuals were studied: 102 with HCC (G1), 117 with cirrhosis (G2), and 127 controls (G3). Polymorphisms were analysed by PCR/RFLP and serum levels of VEGF by ELISA. Alpha error was set at 5%. The wild-type genotype of both polymorphisms prevailed (P > 0.05). In G1, 23% of the patients died, with no relation to genetic profile (P > 0.05). Increased VEGF level was observed in G1 and G3, related to the mutant allele of VEGF-C936T and VEGF-A1154G, respectively, and compared with the wild-type genotype (P = 0.0285; P = 0.0284, resp.) as well as G1 versus G2 and G3 for VEGF-C936T and G1 versus G2 for VEGF-A1154G (P < 0.05 for both). In conclusion, there is a relationship between mutant alleles of VEGF-C936T and VEGF-A1154G polymorphisms and higher VEGF level, making them potential markers for HCC.

Figure 1

Kaplan-Meier curve for overall survival analysis of patients with hepatocellular carcinoma after 36 months of diagnosis. (a) VEGF-C936T: 1 = genotype C/T, 0 = genotype C/C; (b) VEGF-A1154G: 1 = genotypes _ /A, 0 = genotype G/G; df = degree of freedom.

Figure 2

Box-plot representation of median and quartile values of serum vascular endothelial growth factor (VEGF) levels. HCC: median = 264.8, minimum = 102.0, maximum = 1795.1, Q1 = 199.4, Q3 = 467.7, and IQRange = 268.3; cirrhosis: median = 182.8, minimum = 7.2, maximum = 993.0, Q1 = 103.9, Q3 = 287.4, and IQRange = 183.5; control: median = 182.2, minimum = 31.6, maximum = 666.1, Q1 = 66.14, Q3 = 265.5, and IQRange = 199.4. ^∗Extreme outliers of the distribution of serum levels values. Extreme outliers are observations that are beyond one of the outer fence OF1 or OF2. The outer fences are calculated as follows: OF1 = Q1 − 3∗IQR, OF2 = Q3 + 3∗IQR.

Figure 3

Receiver operator characteristic curve (ROC) of serum vascular endothelial growth factor (VEGF) levels in patients with (○) mutant allele of VEGF-C936T in the group with hepatocellular carcinoma (G1) and cirrhosis (G2) (area under the curve = 0.80 [0.60–1.0]), with sensitivity of 63% and specificity of 93%, to the cut-off value of 311.8 pg/mL; (□) mutant allele of VEGF-C936T in G1 and controls (G3) (area under the curve = 0.89 [0.60–1.0]), with sensitivity of 75% and specificity of 100%, to the cut-off value of 225.5 pg/mL; (∆) mutant allele of VEGF-A1154G in G1 and G2 (area under the curve = 0.76 [0.60–0.92]), with sensitivity of 76% and specificity of 65%, to the cut-off value of 222.1 pg/mL.