Differential in vitro effects of targeted therapeutics in primary human liver cancer: importance for combined liver cancer.

The incidence of primary liver tumors, hepatocellular carcinoma (HCC), intrahepatic cholangiocellular carcinoma (ICC), and combined HCC/ICC (cHCC/CC) is increasing. For ICC, targeted therapy exists only for a small subpopulation of patients, while for HCC, Sorafenib and Lenvatinib are in use. Diagnosis of cHCC/CC is a great challenge and its incidence is underestimated, bearing the risk of unintended non-treatment of ICC. Here, we investigated effects of targeted inhibitors on human ICC cell lines (HUH28, RBE, SSP25), in comparison to extrahepatic (E)CC lines (EGI1, CCC5, TFK1), and HCC/hepatoblastoma cell lines (HEP3B, HUH7, HEPG2). Cells were challenged with: AKT inhibitor MK-2206; multikinase inhibitors Sorafenib, Lenvatinib and Dasatinib; PI3-kinase inhibitors BKM-120, Wortmannin, LY294002, and CAL-101; and mTOR inhibitor Rapamycin. Dosage of the substances was based on the large number of published data of recent years. Proliferation was analyzed daily for four days. All cell lines were highly responsive to MK-2206. Thereby, MK-2206 reduced expression of phospho(p)-AKT in all ICC, ECC, and HCC lines, which mostly corresponded to reduction of p-mTOR, whereas p-ERK1/2 was upregulated in many cases. Lenvatinib showed inhibitory effects on the two HCC cell lines, but not on HEPG2, ICCs and ECCs. Sorafenib inhibited proliferation of all cells, except the ECC line CCC5. However, at reduced dosage, we observed increased cell numbers in some ICC experiments. Dasatinib was highly effective especially in ICC cell lines. Inhibitory effects were observed with all four PI3-kinase inhibitors. However, cell type-specific differences were also evident here. Rapamycin was most effective in the two HCC cell lines. Our studies show that the nine inhibitors differentially target ICC, ECC, and HCC/hepatoblastoma lines. Caution should be taken with Lenvatinib and Sorafenib administration in patients with cHCC/CC as the drugs may have no effects on, or might even stimulate, ICC.

Hepatic Interferon-λ3 (IFNL3) Gene Expression Reveals Not to Be Attenuated in Non-Favorable IFNL3 rs4803217 or IFNL4 rs368234815 Minor Allele Carriers in Chronic Hepatitis C.

Genetic polymorphisms in the region of the interferon-λ genes (IFNL) associate with clearance of hepatitis C virus (HCV) infection. One of these polymorphisms, IFNL4 rs368234815, determines loss or gain of function of the IFNL4 gene by frameshift variation. The very same and a second one, IFNL3 rs4803217, are supposed to impact the expression of IFNL3: while IFNL4 rs368234815 is suggested to modulate IFNL3 transcription, IFNL3 rs4803217 is thought to alter IFNL3 mRNA stability. The latter process is believed to be partially driven by an HCV-induced ectopic expression of myosin heavy chain genes 7B and 7 and their co-expressed microRNAs mir499 and mir208B. These ideas are evidenced by functional investigations on peripheral blood mononuclear and hepatoma cells in culture. Our study aimed at exploring IFNL3 gene expression in clinical samples, i.e., in ex vivo derived liver tissue from patients with chronic hepatitis C (n = 57) and various other diseases (n = 56). By applying an assay designed to specifically quantify IFNL3 and discriminating paralogous IFNL2 transcripts, IFNL3 mRNA expression was not found to differ significantly between chronic hepatitis C and control samples. Among patients with chronic HCV infection, moreover, IFNL3 rs4803217 or IFNL4 rs368234815 minor alleles did not associate with reduced IFNL3 gene expression. Finally, myosin heavy chain genes 7B and 7 and corresponding microRNAs mir499 and mir208B were not found activated in liver in chronic HCV infection. Of note, detectability of MYH7 mRNA related to the procedure of liver biopsy sampling, as tissue obtained by direct punctation of the liver during laparoscopic inspection was less likely to contain MYH7 transcripts than samples acquired by percutaneous punctation. In conclusion, data on ex vivo derived liver tissue samples argue against an attenuating impact of IFNL3 rs4803217 or IFNL4 rs368234815 minor alleles on hepatic IFNL3 gene expression in vivo.