Mahmut Yasen

Aurora kinase B is a predictive factor for the aggressive recurrence of hepatocellular carcinoma after curative hepatectomy

Patterns of cancer recurrence hold the key to prognosis after curative resection. This retrospective study aimed to identify a predictor and therapeutic candidate for aggressive recurrence of hepatocellular carcinoma (HCC).

The Up-Regulation of Y-Box Binding Proteins (DNA Binding Protein A and Y-Box Binding Protein-1) as Prognostic Markers of Hepatocellular Carcinoma

Purpose: The development of hepatocellular carcinoma is associated with the chronic inflammation of the liver caused by various factors such as hepatitis B or C virus infection. Previously, we reported DNA binding protein A (dbpA) as a candidate molecule that can accelerate inflammation-induced hepatocarcinogenesis. DbpA belongs to the Y-box binding protein family, and Y-box binding protein-1 (YB-1), the prototype member of this family, is reported to be a prognostic marker of malignant diseases other than hepatocellular carcinoma. The purpose of this study is to examine the significance of the expression of dbpA or of the T-to-G transversion in the dbpA promoter region, which enhances the promoter activity in vitro, for the progression of hepatocellular carcinoma. Experimental Design: We studied the expression of dbpA (as well as of YB-1) in 82 formalin-fixed hepatocellular carcinoma tissues by immunohistochemistry and determined the sequence of the dbpA promoter region in 42 frozen hepatocellular carcinoma tissues. We examined the relationship between these findings and the clinicopathologic factors of hepatocellular carcinoma patients. Results: DbpA expression was associated with the advanced stages of hepatocellular carcinoma, and the cases with the nuclear dbpA expression had a poor prognosis. DbpA contributed more significantly to this association than YB-1. Furthermore, the T-to-G transversion in the dbpA promoter region was related to the nuclear localization of dbpA. Conclusion: DbpA was a more significant prognostic marker of hepatocellular carcinoma than YB-1. The T-to-G transversion in the dbpA promoter region was suggested to be a predisposing factor for the progression of hepatocellular carcinoma.

The selective Aurora B kinase inhibitor AZD1152 as a novel treatment for hepatocellular carcinoma

BACKGROUND & AIMS We previously identified that high Aurora B expression was associated with hepatocellular carcinoma (HCC) recurrence due to tumor dissemination. In this preclinical study, a novel inhibitor of Aurora B kinase was evaluated as a treatment for human HCC. METHODS AZD1152 is a selective inhibitor of Aurora B kinase. Twelve human HCC cell lines were analyzed for Aurora B kinase expression and the in vitro effects of AZD1152. The in vivo effects of AZD1152 were analyzed in a subcutaneous xenograft model and a novel orthotopic liver xenograft model. RESULTS Aurora B kinase expression varied among the human HCC cell lines and was found to correlate with inhibition of cell proliferation, accumulation of 4N DNA, and the proportion of polyploid cells following administration of AZD1152-hydroxyquinazoline-pyrazol-anilide (AZD1152-HQPA). AZD1152-HQPA suppressed histone H3 phosphorylation and induced cell death in a dose-dependent manner. Growth of subcutaneous human HCC xenografts was inhibited by AZD1152 administration. In an orthotopic hepatoma model, treatment with AZD1152 significantly decelerated tumor growth and increased survival. Pharmacobiological analysis revealed that AZD1152 induced the rapid suppression of phosphohistone H3, followed by cellular apoptosis in the liver tumors but not in the normal tissues of the orthotopic models. CONCLUSIONS Our preclinical studies indicate that AZD1152 is a promising novel therapeutic approach for the treatment of HCC.

Gene expression signature of the gross morphology in hepatocellular carcinoma.

Objective:To evaluate the gene expression signature of hepatocellular carcinoma (HCC) in relation to the gross morphology. Background:Eggels nodular type of HCC is morphologically subclassified into the single nodular (SN) type, the single nodular type with extranodular growth (SNEG), and the confluent multinodular (CM) type, but their biomolecular differences remain unclear. Methods:The clinicopathological characteristics and genome-wide gene expressions were analyzed in 275 patients with nodular-type HCC (124 SN-type, 91 SNEG-type, and 60 CM-type) who received curative hepatectomy. Results:Significantly poor prognosis was recognized in CM types in overall survival (P = 0.0020) and recurrence-free survival (P = 0.0066). Analysis of the genome-wide expression patterns revealed significant difference of CM-type HCC from either SN- or SNEG-type HCC. In particular, a stem cell marker EpCAM was dominantly expressed in CM-type HCC. Immunohistochemical studies confirmed the specific expression of EpCAM in HCC cancer cells of CM type. In multivariate analysis, the gross morphology of CM type was significantly associated with EpCAM expression (P = 0.0092), &agr;-fetoprotein (P = 0.0424), “lens culinaris agglutinin-reactive fraction of &agr;-fetoprotein” level (P = 0.0288), and the portal vein invasion (P = 0.0150). Furthermore, EpCAM was predictive for poor prognosis in overall and recurrence-free survivals of patients with CM-type HCC (P = 0.0082 and P = 0.0043, respectively). Conclusion:Our studies suggest that the distinct signature of gene expression is closely related to morphological progression in HCC. Especially, EpCAM might play a critical role in the aggressiveness of CM-type HCC.

Expression of Aurora B and alternative variant forms in hepatocellular carcinoma and adjacent tissue

Surgical resection is the effective treatment modality for hepatocellular carcinoma (HCC); however, rapid recurrence of the tumors are frequently observed even after apparently curative resection. The recurrence and prognostic assessment of patients with HCC after resection is an important clinical issue. We recently reported that aberrant expression of Aurora B is observed in primary HCC, and that it can be a predictive factor for HCC recurrence exceeding Milan criteria after curative hepatectomy. In this study we investigated the expression of the newly observed Aurora B splicing variant forms in HCC, and their roles in hepatocarcinogenisis. The expression of Aurora B and splicing variant forms were screened in 125 HCC patients (94 chronic hepatitis with cirrhosis background liver specimens), 18 metastatic liver cancer patients and 16 normal liver specimens by cDNA microarray, reverse transcription – polymerase chain reaction (RT–PCR) and Real time quentitative Reverse Transcription PCR (qRT‐PCR). The results showed that expression of Aurora B splicing variant 2 (AURKB‐Sv2) variant form was absent in normal liver and was higher in metastatic liver cancer than HCC. This aberrant expression was associated with the advanced stages of HCC (P < 0.01), correlated with a poor outcome (P = 0.008) and short disease‐free period (P = 0.018). Furthermore, AURKB‐Sv2 variant form is associated with a higher level of serum α‐fetoprotein, protein induced by vitamin K absence or antagonist‐II (PIVKAII), tumor capsular invasion, multiple tumor formation and at an age younger than those with other variant forms (P < 0.05). The results thus suggest that AURKB‐Sv2 variant form is more significantly associated with the advanced stages of HCC than others and is a marker of poor prognosis. Founded in the tumor capsular invasion and multiple tumor regions, suggests that this might play a role in enhancing multiple malignant tumor formation and recurrence of HCC in hepatocarcinogenesis. This is the first study to report clinicopathological significance of aberrant expression of AURKB‐Sv2 variant form in hepatocellular carcinoma. (Cancer Sci 2009; 100: 472–480)

Oxidative stress pathways in noncancerous human liver tissue to predict hepatocellular carcinoma recurrence: A prospective, multicenter study†‡

The prediction of cancer recurrence holds the key to improvement of the postoperative prognosis of patients. In this study, the recurrence of early‐stage hepatocellular carcinoma (HCC) after curative hepatectomy was analyzed by the genome‐wide gene‐expression profiling on cancer tissue and the noncancerous liver tissue. Using the training set of 78 cases, the cytochrome P450 1A2 (CYP1A2) gene in noncancerous liver tissue was identified as the predictive candidate for postoperative recurrence (hazard ratio [HR], 0.447; 95% confidence interval [CI], 0.249‐0.808; P = 0.010). Multivariate analysis revealed the statistically significant advantage of CYP1A2 down‐regulation to predict recurrence (odds ratio, 0.534; 95% CI, 0.276‐0.916; P = 0.036), and the expression of CYP1A2 protein was confirmed immunohistochemically. An independently multi‐institutional cohort of 211 patients, using tissue microarrays, validated that loss of expression of CYP1A2 in noncancerous liver tissue as the only predictive factor of recurrence after curative hepatectomy for early‐stage HCC (HR, 0.480; 95% CI, 0.256‐0.902; P = 0.038). Gene set‐enrichment analysis revealed close association of CYP1A2 down‐regulation with oxidative stress pathways in liver tissue (P < 0.001, false discovery rate [FDR] = 0.042; P = 0.006, FDR = 0.035). Our results indicate these pathways as the molecular targets to prevent recurrence, as well as the potential prediction of the super high‐risk population of HCC using liver tissue. (HEPATOLOGY 2011;54:1273–1281)

Surgical Contribution to Recurrence-Free Survival in Patients with Macrovascular–Invasion−Negative Hepatocellular Carcinoma

BACKGROUND Macroscopic vascular invasion (MVI) is a well-known indicator of recurrence of hepatocellular carcinoma (HCC) even after curative hepatectomy, but the clinicopathologic and molecular features of the recurrence remain unclear in MVI-negative HCC. STUDY DESIGN Two hundred seven consecutive patients with confirmed primary MVI-negative HCC were retrospectively assessed after curative resection, with special emphasis on the importance of anatomically systematized hepatectomy. HCC tissues were also analyzed for genome-wide gene expression profile of each tumor using a microarray technique. RESULTS Univariant analysis of HCC recurrence revealed multiple tumors (p < 0.001), moderate to poor differentiation (p = 0.044), Child-Pugh B/C (p = 0.047), alpha-fetoprotein elevation (p = 0.007), and nonanatomic hepatectomy (p = 0.010) as risk factors. According to Cox hazard multivariant analysis, multiple tumors (p = 0.002), alpha-fetoprotein elevation (p < 0.001), and nonanatomic hepatectomy (p = 0.002) were identified as independent factors of the recurrence. In the recurrent cases after anatomic hepatectomy for HCC, local recurrence was significantly infrequent compared with those after nonanatomic hepatectomy (p < 0.001). Network expression analysis using cDNA microarray revealed distinct signaling pathways of epithelial-mesenchymal transitions are associated with recurrence after anatomically systematized hepatectomy. CONCLUSIONS Anatomically systematized hepatectomy might contribute to recurrence-free survival of HCC patients of HCC without MVI. Local recurrence could be mostly averted by anatomic hepatectomy, although specific epithelial-mesenchymal transitions signaling might regulate the biologic aggressiveness of HCC.

Contrast‐enhanced intraoperative ultrasonography for vascular imaging of hepatocellular carcinoma: Clinical and biological significance

Abnormal tumor vascularity is one of the typical features of hepatocellular carcinoma (HCC). In this study, the significance of contrast‐enhanced intraoperative ultrasonography (CEIOUS) images of HCC vasculature was evaluated by clinicopathological and gene expression analyses. We enrolled 82 patients who underwent curative hepatic resection for HCC with CEIOUS. Clinicopathological and gene expression analyses were performed according to CEIOUS vasculature patterns. CEIOUS images of HCC vasculatures were classified as reticular HCC or thunderbolt HCC. Thunderbolt HCC was significantly correlated with higher alpha‐fetoprotein levels, tumor size, histological differentiation, portal vein invasion, and tumor‐node‐metastasis stage, and these patients demonstrated a significantly poorer prognosis for both recurrence‐free survival (P = 0.0193) and overall survival (P = 0.0362) compared with patients who had reticular HCC. Gene expression analysis revealed that a rereplication inhibitor geminin was significantly overexpressed in thunderbolt HCCs (P = 0.00326). In vitro knockdown of geminin gene reduced significantly the proliferation of human HCC cells. Immunohistochemical analysis confirmed overexpression of geminin protein in thunderbolt HCC (P < 0.0001). Multivariate analysis revealed geminin expression to be an independent factor in predicting poor survival in HCC patients (P = 0.0170). Conclusion: CEIOUS vascular patterns were distinctly identifiable by gene expression profiling associated with cellular proliferation of HCC and were significantly related to HCC progression and poor prognosis. These findings might be clinically useful as a determinant factor in the postoperative treatment of HCC. (HEPATOLOGY 2013)

Gene-expression phenotypes for vascular invasiveness of hepatocellular carcinomas.

BACKGROUND Gross vascular invasion is a well-established prognostic indicator in hepatocellular carcinoma (HCC), but the biological significance of microscopic invasion remains unclear. METHODS Curatively resected primary HCCs were classified retrospectively into 3 groups: HCCs without vascular invasion (V0), HCCs with microvascular invasion (V1), and HCCs with macrovascular invasion (V2). Microarray profiling of patients with V0, V1, and V2 using Jonckheere-Terpstra (JT) tests and Wilcoxon rank sum tests was performed. RESULTS Distinct patterns of gene expression were demonstrated between V0 and V2 groups; less (L) and highly (H) invasive phenotypes, respectively. It is noteworthy that 2 dendrograms by the hierarchical clustering provided exactly the same assignment results for V1 cases that were thus separated into L and H gene-expression phenotypes. Marked differences were found in overall (P < .001) and tumor-free survival (P < .001) between L and H gene-expression phenotypes. Multivariate analyses indicated that the phenotypes of the patterns of gene expression, rather than the clinicopathologic markers of vascular invasion, were independent predictors of tumor recurrence (P = .031). Using the gene-expression patterns identified by both JT and Wilcoxon rank sum test analyses, other V1 cases validated these differences in tumor-free survivals between gene-expression phenotypes within the group (P = .039). CONCLUSION Gene profiling suggested that microvascular invasiveness consisted of a classable mixture of 2 distinct phenotypes. Thus, gene-array analyses may have clinical benefit, because they may in fact be more predictive than other clinical factors.

DNA binding protein A expression and methylation status in hepatocellular carcinoma and the adjacent tissue

We investigated the expression and promoter methylation of dbpA in human hepatocellular carcinoma (HCC) and examined their correlation with clinicopathological features. In 96 paired samples of HCC and adjacent non-tumorous liver, and 10 normal liver specimens, dbpA mRNA was quantified by real-time RT-PCR, and promoter methylation was examined by methylation-specific polymerase chain reaction and bisulfite sequencing. The results showed that dbpA mRNA expression levels were higher in HCC compared to corresponding non-tumor tissues (P<0.01) and higher in non-virus-associated HCC compared to virus-associated cases (P<0.01). dbpA promoter was methylated in 37.7% of HCC samples and the promoter methylation was significantly correlated with the low expression of dbpA in non-virus-associated HCC (P<0.01), but not in virus-associated HCC. Surprisingly, poor prognosis was more significantly associated with high dbpA expression in non-tumorous liver (P=0.018) but not with that in HCC. Non-tumorous tissues consist of chronic hepatitis or liver cirrhosis, and these conditions are the background of hepatocarcinogenesis, defined as the hypercarcinogenic state. Our results suggest that the high expression of dbpA in the hypercarcinogenic state is an indicator of poor prognosis.