P-227 Overexpression of survivin-1, TAG-72 and HERC5 in patients diagnosed with hepatocellular carcinoma in the Black Sea Coast geographical area

Abstract

Epidemiological data regarding hepatocellular carcinoma (HCC) report unsatisfactory morbimortality rates despite the global efforts to decrease the incidence and prolong patient survival. Current guidelines lack diagnostic biomarkers to better characterize patients with HCC. We aimed to validate the overexpression of Survivin-1, tumor-associated glyocoprotein 72 (Tag-72), and HECT and RLD domain containing E3 ubiquitin protein ligase 5 (HERC5) as tissue biomarkers for HCC characterization in patients from our geographical area and to standardize a local biomarker panel to be introduced in the current management guideline. Thirty liver specimens of HCC and a similar number of liver tissue specimens of benign liver tumors were selected from the Gastroenterology file database and Pathology Clinic registries from St. Apostle Andrew Emergency Clinical Hospital, Constanta and Fundeni Institute, Bucharest and compared in terms of Survivin-1, Tag-72, and HERC5 overexpression. The morphological features of the tumors were noted based on the WHO Histological Classification for digestive tumors. Demographic data of all patients providing the liver specimens, as well as liver diseases background like chronic viral infections, other co-morbidities and laboratory parameters recorded at the time of hospital admission were noted. For the IHC assessment, the representative samples were chosen, and 4-μm sections of formalin-fixed, paraffin-embedded tissue blocks were obtained for each case enrolled. Epitope retrieval was conducted prior to incubation of tissue sections with a panel of three primary antibodies (ready-to-use) from Novus Biological: survivin-1 (NB100-911 clone), Tag-72 (CC49 clone), and HERC5 (NBP-91985 clone). The immunostaining protocol for each antibody used was provided by the manufacturer. As chromogen, we used 3,3'diaminobenzidine (DAB), and brown staining was obtained. The final step was represented by counterstaining all slides with Mayer's Hematoxylin. Comparisons of the studied biomarker overexpression from HCC tissue samples with a matched non-HCC group of normal liver tissue specimens were made.Student t-test, Mann-Whitney U-test and Chi-square test were used to find differences between the two studied groups and to compare the categorical variables. The discriminative power of Survivin -1, Tag-72, and HERC5 overexpression was assessed using ROC curves. The multivariate linear regression analysis revealed that Survivin-1, Tag-72, and HERC5 were significantly overexpressed upon IHC analysis in HCC samples in patients older than 50 years (P=0.003, P=0.006, P=0.004), male gender (P=0.031, P=0.004, P=0.020), patients with increased AFP over 180 ng/dl (P=0.012, P=0.004, P=0.029), with low serum albumin < 3 mg/dl (P=0.031, P=0.021, P=0.003, respectively), with imaging features of portal thrombosis (P=0.004, P=0.020, P=0.004, respectively), ascites (P=0.002, P=0.004, P=0.019, respectively) and in BCLC B and C classes patients (P=0.045, P=0.036, P=0.045, and P=0.033, P=0.001, P=0.027, respectively). The diagnostic performance of Survivin-1, Tag-72 and HER-C5 tissue biomarkers for HCC characterization was superior to that of AFP, considered the gold standard biomarker used in clinical guidelines (Survivin-1: Z statistic=2.911, P=0.0039; Tag-72: Z statistic=2.789, P=0.0049, respectively; HERC5: Z statistic=2.844, P=0.0043) and AFP assay alone (Z statistic=5.022, P < 0.0001). Our study results validate the overexpression of Survivin-1, Tag-72, and HERC5 as tissue biomarkers for HCC characterization in patients from our geographical region and could be standardized in the current HCC management guideline.