A Human Model of Epithelial to Mesenchymal Transition to Monitor Drug Efficacy in Hepatocellular Carcinoma Progression

Abstract

The epithelial to mesenchymal transition (EMT) of malignant hepatocytes is a crucial event in hepatocellular carcinoma (HCC) progression and recurrence. We aimed to establish a human model of EMT to examine drug efficacy and specificity in HCC progression. Human HCC cell populations were characterized by immunofluorescence analysis, migration and invasion assays, array comparative genomic hybridization, whole-genome expression profiling, and promoter methylation. Therapeutic agents clinically used against HCC were examined for efficacy by determination of IC 50 values. We show that liver cancer cell lines exhibited either an epithelial or mesenchymal phenotype of which the latter showed strong migratory and invasive abilities in vitro. The common cellular origin of both cell types indicated that mesenchymal HCC cells have been derived from epithelial hepatocytes through EMT in the HCC patient. Drug exposure of mesenchymal HCC cells showed higher resistance to the targeted therapeutic agents sorafenib and erlotinib as compared to epithelial HCC cells, which were slightly more resistant to cytostatic drugs. Most remarkably, combined treatment with doxorubicin and sorafenib caused increased susceptibility of both HCC cell types resulting in enhanced drug efficacy. Taken together, this EMT model of human HCC allows the identification of molecular mechanisms and the assessment of therapeutic drug efficacy during liver cancer progression in preclinical studies. Mol Cancer Ther; 10(5); 850-60. Ó2011 AACR.

Novel Inhibitors of Cyclin-Dependent Kinases Combat Hepatocellular Carcinoma without Inducing Chemoresistance

“…Thus, these data propose BA-12 and BP-14 as substrates of P-gp. In agreement, several studies showed that roscovitine represents a high-affinity substrate of P-gp as well, yet no concomitant ABCB1-mediated resistance could be observed after treatment with roscovitine (26). Noteworthy, roscovitine was also shown to induce apoptosis in a doxorubicinresistant human myeloma cell line that overexpresses Pgp (37).…”

“…Several chemotherapeutics are used of which doxorubicin and cisplatin are most commonly used (36). Compared with doxorubicin, BA-12 shows a similar IC 50 on hepatoma cell lines, whereas BP-14 shows a 10-fold higher efficacy (26). Cisplatin displays an even 10-to 20-fold lower ability of inhibition.…”

“…The human hepatoma cell lines HepG2, PLC/PRF/5 (PLC), Hep3B, and 3sp (formerly described as HCC-1.1) were cultivated as described (25,26). All cells were kept at 37 C and 5% CO 2 and were routinely screened for the absence of mycoplasma.…”

“…The 3sp cells were established from a patient with hepatocellular carcinoma at the Medical University of Vienna (Vienna, Austria; ref. 26). All cell lines were verified by short-tandem repeat analysis in November 2012.…”

High Serum Transforming Growth Factor-β1 Levels Predict Outcome in Hepatocellular Carcinoma Patients Treated with Sorafenib

“…TGF-b is a well-known signaling pathway promoting EMT. Previous studies have shown that EMT can induce resistance to EGFR-targeted therapy in HCC cell lines (29), and mesenchymal-type HCC cells have increased resistance to sorafenib (29,30). In addition, TGF-b may contribute to resistance to molecularly targeted therapy through cross-talk with interleukin-6, as observed in lung cancer cells (31).…”