Different subpopulations of circulating tumor cells in patients with hepatocellular carcinoma and clinical relevance.

Abstract

e15130 Background: The existence of circulating tumor cells (CTCs) in peripheral blood has a correlation with prognosis and tumor metastasis in patients with hepatocellular carcinoma (HCC). Epithelial-mesenchymal transition (EMT) is regarded as pivotal process in tumor metastasis, and plays an important role in tumor local invasion and subsequent dissemination. According to the EMT status, CTCs can be classified into different subpopulations, including epithelial CTCs, mesenchymal CTCs, hybrid (epithelial/mesenchymal) CTCs etc. Furthermore, the mesenchymal CTCs hold a strong metastatic potential. Methods: We isolated CTCs from peripheral blood of 13 HCC patients. The CanPatrol CTC enrichment technique (SurExam China) was used to enumerate and characterize the phenotypes of CTCs. The first step of this technique was to isolate CTCs via a filter-based method; then, a multiplexed mRNA fluorescence in situ hybridization method was used to characterize CTCs according to the expression status of epithelial and mesenchymal biomarkers. Results: Among the 13 patients, 12 patients had detectable CTCs. All CTC-positive patients had detectable hybrid CTCs, four CTC-positive patients had detectable mesenchymal CTCs, and one CTC-positive patient had detectable three phenotypes: epithelial, hybrid and mesenchymal CTCs. Of the four mesenchymal CTC-positive patients, three of them were undergoing metastasis, and it suggested that metastasis in patients with HCC was positive associated with mesenchymal CTCs (p < 0.01). Conclusions: Although the sample size of this study was small, our findings suggested that the existence of mesenchymal CTCs might have a positive correlation with tumor metastasis in HCC.