Yun-Fan Sun

Circulating stem cell–like epithelial cell adhesion molecule–positive tumor cells indicate poor prognosis of hepatocellular carcinoma after curative resection

Epithelial cell adhesion molecule–positive (EpCAM+) hepatocellular carcinoma (HCC) cells may constitute a tumor‐initiating subpopulation in tumorigenic cell lines and HCC specimens. In the present study, EpCAM+ circulating tumor cells (CTCs) were identified prospectively in HCC patients undergoing curative resection, and the prognostic significance and their stem cell–like characteristics were investigated further. Blood samples from 123 HCC patients were tested prior to resection and 1 month thereafter. CTCs were present in 66.67% of patients, and the cell count measured in 7.5 mL of blood (CTC7.5) ranged between 1 and 34. Fifty‐one patients had CTC7.5 of ≥2 preoperatively, and these patients developed tumor recurrence earlier than those with CTC7.5 of <2 CTCs (P < 0.001). A preoperative CTC7.5 of ≥2 was an independent prognostic factor for tumor recurrence (P < 0.001). Its prognostic significance also applied to patients with alpha‐fetoprotein (AFP) levels of ≤400 ng/mL or subgroups with low recurrence risk (all P < 0.05). A significant decrease of CTC‐positive rates (66.67% to 28.15%, P < 0.05) and CTC7.5 values (2.60 ± 0.43 to 1.00 ± 0.36, P < 0.05) was observed 1 month after resection. Patients with consistent CTC7.5 <2 had lower recurrence rates than those with values consistently ≥2 (15.5% versus 87.50%, P < 0.001). EpCAM+ CTCs displayed cancer stem cell biomarkers (CD133 and ABCG2), epithelial‐mesenchymal transition, Wnt pathway activation, high tumorigenic potential, and low apoptotic propensity. Conclusion: Stem cell–like phenotypes are observed in EpCAM+ CTCs, and a preoperative CTC7.5 of ≥2 is a novel predictor for tumor recurrence in HCC patients after surgery, especially in patient subgroups with AFP levels of ≤400 ng/mL or low tumor recurrence risk. EpCAM+ CTCs may serve as a real‐time parameter for monitoring treatment response and a therapeutic target in HCC recurrence. (HEPATOLOGY 2013)

Circulating tumor cells: advances in detection methods, biological issues, and clinical relevance

BackgroundCirculating tumor cells (CTCs) have long been considered a reflection of tumor aggressiveness. Hematogenous spreading of CTCs from a primary tumor is a crucial step in the metastasis cascade, which leads ultimately to the formation of overt metastases. However, owing to the rarity of CTCs in peripheral blood, detecting these cells requires methods combined with high sensitivity and specificity, which sets tremendous challenges for the implementation of these assays into clinical routine.MethodsGenerally, CTCs detection methods are composed of the following two steps: enrichment (isolation) process (morphological and immunological techniques) and detection (identification) process (cytometric and nucleic acid techniques), which may or may not be separate from enrichment. Genetic and molecular characterization of CTCs carried out by fluorescent in situ hybridization (FISH), comparative genomic hybridization (CGH), PCR-based techniques, and biomarker immunofluorescent staining extract more information about malignant profile, metastatic potential of CTCs, and the extent to which CTCs are genetically identical to the primary tumor.ResultsRecent technical advances made it possible to detect CTCs. The efficacy of circulating tumor cell (CTC) detection among patients with solid malignancy has been investigated, which shows great potential to become a tool for real-time parameter of prognosis and serve as an early marker to assess the therapeutic response in overt cancers. Improvements in detection and characterization of CTCs will hopefully lead to refinement of clinical management of cancer patients.ConclusionThis review addresses the majority of assays that have been published thus far, including the enrichment and detection steps and the markers used in these assays, accompanied by some biological issues of CTC and the results of clinical application harvested.

Systemic Immune-Inflammation Index Predicts Prognosis of Patients after Curative Resection for Hepatocellular Carcinoma

Purpose: We developed a novel systemic immune-inflammation index (SII) based on lymphocyte, neutrophil, and platelet counts and explored its prognostic value in hepatocellular carcinoma (HCC). Experimental Design: The SII was developed based on a retrospective study of 133 patients with HCC undergoing resection between 2005 and 2006, and validated in a prospective study of 123 patients enrolled from 2010 to 2011. The circulating tumor cell (CTC) level in the validation cohort was measured using the CellSearch system. Prediction accuracy was evaluated with area under the receiver operating characteristic curve (AUC). Results: An optimal cutoff point for the SII of 330 × 109 stratified the patients with HCC into high (≥330) and low SII (<330) groups in the training cohort. Univariate and multivariate analyses revealed the SII was an independent predictor for overall survival and relapse-free survival, and prognostic for patients with negative α-fetoprotein and Barcelona Clinic Liver Cancer stage 0+A. The AUCs of the SII for survival and recurrence were higher than other conventional clinical indices. An SII ≥ 330 was significantly associated with vascular invasion, large tumors, and early recurrence. CTC levels were significantly higher in the SII ≥ 330 group (1.71 ± 0.34 vs. 4.37 ± 1.04, P = 0.029). In patients with detectable CTCs, those with SII ≥ 330 had higher recurrence rates and shorter survival time than patients with SII < 330. Conclusion: The SII was a powerful prognostic indicator of poor outcome in patients with HCC and is a promising tool for HCC treatment strategy decisions. The dismal outcome in patients with high SII scores might be related to higher CTC levels. Clin Cancer Res; 20(23); 6212–22. ©2014 AACR.

High expression of Dickkopf-related protein 1 is related to lymphatic metastasis and indicates poor prognosis in intrahepatic cholangiocarcinoma patients after surgery

Dickkopf‐related protein 1 (DKK1) has been reported involved in metastasis and invasion in several tumors. This study sought to investigate the prognostic value of DKK1 in intrahepatic cholangiocarcinoma (ICC) and its role in promoting ICC metastasis.

Clinical Significance of EpCAM mRNA-Positive Circulating Tumor Cells in Hepatocellular Carcinoma by an Optimized Negative Enrichment and qRT-PCR–Based Platform

Purpose: This study aimed to construct a novel platform for the detection of circulating tumor cells (CTC) in patients with hepatocellular carcinoma (HCC) and to investigate the clinical significance of epithelial cell adhesion molecule mRNA-positive (EpCAMmRNA+) CTCs using this platform. Experimental Design: An optimized platform for CTC detection was constructed by evaluating different negative enrichment, mRNA isolation, and cDNA synthesis procedures and compared with the CellSearch system. A total of 299 patients with HCC were recruited into this prospective study; of these, 157 who received curative resection, 76 who received transcatheter arterial chemoembolization (TACE), and 66 who received radiotherapy were tested using our platform. The diagnostic value of EpCAMmRNA+ CTCs was investigated in 122 patients with HCC who underwent resection and 120 control subjects. Results: The optimized negative enrichment and quantitative real-time PCR (qRT-PCR)-based CTC detection platform had high sensitivity, specificity, and reproducibility and a low sample volume requirement. This platform showed a potential diagnostic value in patients with HCC and exhibited 76.7% consistency with the CellSearch system (r = 0.54, P < 0.050). Pretreatment CTC level showed prognostic significance in patients with HCC treated with resection, TACE, and radiotherapy (all P < 0.050). Most of the patients showed a decrease in CTC levels after treatment that reflected tumor response. In contrast, patients with an increased CTC level showed disease progression after treatment. Conclusions: We established an optimized platform based on negative enrichment and qRT-PCR for highly sensitive, specific, and reproducible CTC detection. This platform might be clinically useful in auxiliary diagnosis, treatment response assessment, and early decision-making to tailor the most effective antitumor strategies. Clin Cancer Res; 20(18); 4794–805. ©2014 AACR.

Downregulation and pro-apoptotic effect of hypoxia-inducible factor 2 alpha in hepatocellular carcinoma

The role of HIF-2α in hepatocellular carcinoma (HCC) is unclear. The aim of the present study was to investigate the expression pattern and role of HIF-2α in HCC patients. Immunohistochemical staining and western blotting analyses were applied to detect the protein level of HIF-2α in 206 paired HCC and peritumoral tissues. Kaplan-Meier survival and Cox proportional hazard regression analyses were performed to identify risk factors for overall survival and recurrence-free survival in these patients. The function of HIF-2α was studied in HCC cells and in vivo models. We found that the protein levels of HIF-2α in HCC tissues were lower than in peritumoral tissues, and were negatively correlated with tumor size (P < 0.05). Kaplan-Meier survival and univariate analysis revealed that HCC patients with high HIF-2α protein levels had longer overall survival (P < 0.05). Over-expression of HIF-2α induced apoptosis in HCC cells and increased the levels of pro-apoptotic proteins, Bak, ZBP-89 and PDCD4, whereas the inhibition of HIF-2α expression achieved opposite results. The findings were confirmed in a mouse HCC xenograft model. In conclusion, our study revealed that HIF-2α was decreased and played an anti-tumorigenic role in HCC.

Circulating CD14+HLA‐DR‐/low myeloid‐derived suppressor cells predicted early recurrence of hepatocellular carcinoma after surgery

Myeloid‐derived suppressor cells (MDSCs) play an important role in tumor progression. The aim of the present study was to investigate the prognostic value of MDSCs for early recurrence of hepatocellular carcinoma (HCC) in patients undergoing curative resection.

Circulating Tumors Cells from Different Vascular Sites Exhibit Spatial Heterogeneity in Epithelial and Mesenchymal Composition and Distinct Clinical Significance in Hepatocellular Carcinoma.

Purpose: The spatial heterogeneity of phenotypic and molecular characteristics of CTCs within the circulatory system remains unclear. Herein, we mapped the distribution and characterized biological features of CTCs along the transportation route in hepatocellular carcinoma (HCC). Experimental Design: In 73 localized HCC patients, blood was drawn from peripheral vein (PV), peripheral artery (PA), hepatic veins (HV), infrahepatic inferior vena cava (IHIVC), and portal vein (PoV) before tumor resection. Epithelial and mesenchymal transition (EMT) phenotype in CTCs were analyzed by a 4-channel immunofluorescence CellSearch assay and microfluidic quantitative RT-PCR. The clinical significance of CTCs from different vascular sites was evaluated. Results: The CTC number and size gradient between tumor efferent vessels and postpulmonary peripheral vessels was marked. Tracking the fate of CTC clusters revealed that CTCs displayed an aggregated–singular-aggregated manner of spreading. Single-cell characterization demonstrated that EMT status of CTCs was heterogeneous across different vascular compartments. CTCs were predominantly epithelial at release, but switched to EMT-activated phenotype during hematogeneous transit via Smad2 and β-catenin related signaling pathways. EMT activation in primary tumor correlated with total CTC number at HV, rather than epithelial or EMT-activated subsets of CTCs. Follow-up analysis suggested that CTC and circulating tumor microemboli burden in hepatic veins and peripheral circulation prognosticated postoperative lung metastasis and intrahepatic recurrence, respectively. Conclusions: The current data suggested that a profound spatial heterogeneity in cellular distribution and biological features existed among CTCs during circulation. Multivascular measurement of CTCs could help to reveal novel mechanisms of metastasis and facilitate prediction of postoperative relapse or metastasis pattern in HCC. Clin Cancer Res; 24(3); 547–59. ©2017 AACR.

Promyelocytic leukemia protein induces arsenic trioxide resistance through regulation of aldehyde dehydrogenase 3 family member A1 in hepatocellular carcinoma

Clinical response of hepatocellular carcinoma (HCC) to arsenic trioxide (ATO) has been poor. Promyelocytic leukemia protein (PML) is central to ATO treatment efficacy of acute promyelocytic leukemia. We examine impacts of PML expression on the effectiveness of ATO treatment in HCC. We show that increased PML expression predicts longer survival and lower cancer recurrence rates after HCC resection. However, high PML expression dampens the anti-tumor effects of ATO in HCC cells. Gene microarray analysis shows that reduced PML expression significantly down-regulates expression of aldehyde dehydrogenase 3 family member A1 (ALDH3A1). ALDH3A1 depression facilitates accumulation of ATO-induced reactive oxygen species. Chromatin immunoprecipitation analysis and promoter activity assays confirm that PML regulates ALDH3A1 expression through binding to the promoter region of ALDH3A1. Clinically, ATO treatment decreases the disease progression rate in advanced HCC patients with negative PML expression. In conclusion, PML confers a favorable prognosis in HCC patients, but it induces ATO resistance through ALDH3A1 up-regulation in HCC cells. ATO is effective for HCC patients with negative PML expression. Combined with an ALDH3A1 inhibitor, ATO may be efficacious in patients with positive PML expression.

Application of Serum Annexin A3 in Diagnosis, Outcome Prediction and Therapeutic Response Evaluation for Patients with Hepatocellular Carcinoma

PurposeAnnexin A3 (ANXA3) could induce progression of hepatocellular carcinoma (HCC) via promoting stem cell traits of CD133-positive cells. Moreover, serum ANXA3 showed preliminary diagnostic potential, however further validation was required. Meanwhile, the prognostic value of ANXA3 remained elusive. The present study aimed to validate diagnostic performance and further systematically investigate the prognostic value of serum ANXA3.MethodsSerum ANXA3 of 368 HCC patients was determined by enzyme-linked immunosorbent assay (ELISA); 295 of these patients underwent resection and 73 underwent transcatheter arterial chemoembolization (TACE). Diagnostic performance of ANXA3 was evaluated by receiver operating characteristic (ROC) analysis, and the prognostic value was evaluated by Cox regression and Kaplan–Meier analysis. To evaluate the relationship between serum ANXA3 and circulating CD133 mRNA-positive tumor cells (CD133mRNA+ CTCs), real-time polymerase chain reaction was conducted in 69 patients who underwent resection.ResultsSerum ANXA3 provided greater diagnostic performance than α-fetoprotein (area under the curve [AUC] 0.869 vs. 0.782), especially in early diagnosis (AUC 0.852 vs. 0.757) and discriminating HCC from patients at risk (0.832 vs. 0.736). Pretreatment ANXA3 was an independent predictor of tumor recurrence (hazard ratio [HR] 1.87, 95% confidence interval [CI] 1.26–2.76, p = 0.002)/progression (HR 1.88, 95% CI 1.04–3.43, p = 0.038) and survival (resectable: HR 2.26, 95% CI 1.44–3.56, p = 0.001; unresectable: HR 2.08, 95% CI 1.10–4.05, p = 0.025), and retained its performance in low-recurrence-risk subgroups. Specifically, dynamic changes of ANXA3-positive status was associated with worse prognosis. ANXA3 was positively correlated with CD133mRNA+ CTCs (r = 0.601, p < 0.001). In patients with detectable CD133mRNA+ CTC, high ANXA3 was positively associated with a higher risk of recurrence and shorter overall survival.ConclusionsSerum ANXA3 shows promise as a biomarker for diagnosis, outcome prediction, and therapeutic response evaluation in patients with HCC.