Purpose: We aimed to characterize the role of selenium-binding protein 1 (SBP1) in hepatocellular carcinoma (HCC) invasiveness and underlying clinical significance. Experimental Design: SBP1 expression was measured in stepwise metastatic HCC cell lines by Western blotting. The role of SBP1 in HCC was investigated using siRNA. Immunofluorescence analyses were used to detect the interaction between SBP1 and glutathione peroxidase 1 (GPX1). Nineteen fresh tumor tissues and 323 paraffin-embedded samples were used to validate in vitro findings and to detect the prognostic significance of SBP1, respectively. Results: Inhibition of SBP1 effectively increased cell motility, promoted cell proliferation, and inhibited apoptosis only under oxidative stress; it also greatly enhanced GPX1 activity without altering GPX1 expression and downregulated hypoxia-inducible factor-1α (HIF-1α) expression. SBP1 and GPX1 formed nuclear bodies and colocalized under oxidative stress. In freshly isolated clinical HCC tissues, decreased SBP1 was linked with increased GPX1 activity and correlated with vascular invasion. Tumor tissue microarrays indicated that SBP1 was an independent risk factor for overall survival and disease recurrence; patients with lower SBP1 expression experienced shorter overall survival periods and higher rates of disease recurrence (P < 0.001). Further analyses indicated that the predictive power of SBP1 was more significant for patients beyond the Milan criteria than patients within the Milan criteria. Conclusions: Decreased expression of SBP1 could promote tumor invasiveness by increasing GPX1 activity and diminishing HIF-1α expression in HCC; SBP1 could be a novel biomarker for predicting prognosis and guiding personalized therapeutic strategies, especially in patients with advanced HCC. Clin Cancer Res; 18(11); 3042–53. ©2012 AACR.

Histological differentiation is a major pathological parameter associated with poor prognosis in patients with hepatocellular carcinoma (HCC) and the molecular signature underlying HCC differentiation may involve key proteins potentially affecting the malignant characters of HCC. To develop prognostic biomarkers for HCC, we examined the global protein expression profiles of 45 surgically resected tissues, including 27 HCCs with different degree of histological differentiation, 11 adjacent nontumor tissues, and seven normal liver tissues. Unsupervised classification grouped the 45 samples according to their histological classification based on the protein expression profiles created by laser microdissection and two-dimensional difference gel electrophoresis (2D-DIGE). Statistical analysis and mass spectrometry identified 26 proteins with differential expression, of which 14 were functionally linked to c-Myc, AP-1, HIF1A, hepatocyte nuclear factor 4 alpha, or the Ras superfamily (RhoA, CDC42, and Rac1). Among the proteins identified, we focused on APC-binding protein EB1 (EB1) because it was dominantly expressed in poorly differentiated HCCs, which generally correlate with the poor prognosis in patients with HCC. In addition, EB1 is controlled by c-Myc, RhoA, and CDC42, which have all been linked to HCC malignancy. Immunohistochemistry in a further 145 HCC cases revealed that EB1 significantly correlated with the degree of histological differentiation ( P < 0.001), and univariate and multivariate analyses indicated that EB1 is an independent prognostic factor for recurrence (hazard ratio, 2.740; 95% confidence interval, 1.771–4.239; P < 0.001) and survival (hazard ratio, 2.256; 95% confidence interval, 1.337–3.807; P = 0.002) of patients with HCC after curative surgery. Conclusion : Proteomic profiling revealed the molecular signature behind the progression of HCC, and the prognostic value of EB1 in HCC. (Hepatology 2008;48:1851-1863.)

To develop a prognostic biomarker for esophageal squamous cell carcinoma (ESCC), we examined the proteomic profile of ESCC using two‐dimensional difference gel electrophoresis (2D‐DIGE), and identified proteins associated with prognosis by mass spectrometry. The prognostic performance of the identified proteins was examined by immunohistochemistry in additional cases. We identified 22 protein spots whose intensity was statistically different between ESCC cases with good (N = 9; survived more than 5 years without evidence of recurrence) and poor (N = 24; died within 2 years postsurgery) prognosis, within the patient group that had two or more lymph node metastases. Mass spectrometric protein identification resulted in 18 distinct gene products from the 22 protein spots. Transglutaminase 3 (TGM3) was inversely correlated with shorter patient survival. The prognostic performance of TGM3 was further examined by immunohistochemistry in 76 ESCC cases. The 5‐year disease‐specific survival rate was 64.5% and 32.1% for patients with TGM3‐positive and TGM3‐negative tumors, respectively (p = 0.0033). Univariate and multivariate analyses revealed that TGM3 expression was an independent prognostic factor among the clinicopathologic variables examined. It is noteworthy that the prognostic value of TGM3 was shown to be higher than those of the lymph node metastasis, intramural metastasis and vascular invasion status. These results establish TGM3 as a novel prognostic biomarker for ESCC for the first time. Examination of TGM3 expression may provide novel therapeutic strategies to prevent recurrence of ESCC.

CIC-DUX4 sarcoma (CDS) is a group of rare, mesenchymal, small round cell tumours that harbour the unique CIC-DUX4 translocation, which causes aberrant gene expression. CDS exhibits an aggressive course and poor clinical outcome, thus novel therapeutic approaches are needed for CDS treatment. Although patient-derived cancer models are an essential modality to develop novel therapies, none currently exist for CDS. Thus, the present study successfully established CDS patient-derived xenografts and subsequently generated two CDS cell lines from the grafted tumours. Notably, xenografts were histologically similar to the original patient tumour, and the expression of typical biomarkers was confirmed in the xenografts and cell lines. Moreover, the xenograft tumours and cell lines displayed high Src kinase activities, as assessed by peptide-based tyrosine kinase array. Upon screening 119 FDA-approved anti-cancer drugs, we found that only actinomycine D and doxorubicin were effectively suppress the proliferation among the drugs for standard therapy for Ewing sarcoma. However, we identified molecular targeting reagents, such as bortezomib and crizotinib that markedly suppressed the growth of CDS cells. Our models will be useful modalities to develop novel therapeutic strategies against CDS.