...for the Phenotypic Profiling of Circulating Tumor Cells in Hepatocellular Carcinoma.

Abstract here...

Court, CM et al., Liver Transpl. 2018 Apr 6. doi: 10.1002/lt.25062

Current clinicopathologic staging systems and serum biomarkers poorly discriminate tumor biology in hepatocellular carcinoma (HCC), with high recurrence rates following curative-intent surgical resection and liver transplantation (LT). Identification of accurate biomarkers for improved prognostication and treatment selection is a critical unmet need. We sought to develop a novel "liquid-biopsy" assay capable of detecting HCC circulating tumor cells (CTCs), and characterizing phenotypic subpopulations with prognostic significance. Utilizing HCC cell lines, a tissue microarray, and human blood samples, an antibody cocktail targeting the cell-surface markers asialoglycoprotein receptor (ASGPR), Glypican-3,

and epithelial cell adhesion molecule (EpCAM) was optimized for HCC-CTC capture utilizing the NanoVelcro microfluidic assay. The ability of HCC-CTCs and vimentin(+)-CTCs (a subpopulation expressing an epithelial-to-mesenchymal phenotype) to accurately discriminate tumor stage, recurrence, progression, and overall survival was evaluated in a prospective study of 80 patients. Multimarker capture detected greater numbers of CTCs than any individual antibody alone for both cell line and patient samples (p<0.05). HCC-CTCs were identified in 59/61 patients (97%), and accurately discriminated HCC (median: 6 CTCs) and non-HCC patients (median: 1 CTC; AUROC=0.92, p<0.0001; sensitivity=84.2%, specificity=88.5%). Vimentin(+)-CTCs accurately discriminated early-stage, LT eligible patients (median: 0 CTCs) from locally advanced/metastatic, LT ineligible patients (median: 6 CTCs; AUROC=0.89, p<0.0001; sensitivity=87.1%, specificity=90.0%), and predicted overall survival for all patients (HR 2.21, p=0.001), and faster recurrence after curative-intent surgical or locoregional therapy in potentially curable early stage HCC (HR 3.14, p=0.002). In conclusion, we developed a novel multimarker CTC enrichment assay that detects HCC-CTCs with high efficiency and accuracy. A phenotypic subpopulation of vimentin(+)-CTCs appears to signify the presence of aggressive underlying disease and occult metastases, and may have important implications for treatment selection.