Sorafenib Treatment and Modulation of the Sphingolipid Pathway Affect Proliferation and Viability of Hepatocellular Carcinoma In Vitro

Abstract

Hepatocellular carcinoma (HCC) shows a remarkable heterogeneity and is recognized as a chemoresistant tumor with dismal prognosis. In previous studies, we observed significant alterations in the serum sphingolipids of patients with HCC. This study aimed to investigate the in vitro effects of sorafenib, which is the most widely used systemic HCC medication, on the sphingolipid pathway as well as the effects of inhibiting the sphingolipid pathway in HCC. Huh7.5 and HepG2 cells were stimulated with sorafenib, and inhibitors of the sphingolipid pathway and cell proliferation, viability, and concentrations of bioactive metabolites were assessed. We observed a significant downregulation of cell proliferation and viability and a simultaneous upregulation of dihydroceramides upon sorafenib stimulation. Interestingly, fumonisin B1 (FB1) and the general sphingosine kinase inhibitor SKI II were able to inhibit cell proliferation more prominently in HepG2 and Huh7.5 cells, whereas there were no consistent effects on the formation of dihydroceramides, thus implying an involvement of distinct metabolic pathways. In conclusion, our study demonstrates a significant downregulation of HCC proliferation upon sorafenib, FB1, and SKI II treatment, whereas it seems they exert antiproliferative effects independently from sphingolipids. Certainly, further data would be required to elucidate the potential of FB1 and SKI II as putative novel therapeutic targets in HCC.

TM6SF2/PNPLA3/MBOAT7 Loss-of-Function Genetic Variants Impact on NAFLD Development and Progression Both in Patients and in In Vitro Models

“…Therefore, after a day, cells were treated with either sorafenib at a final concentration of 5 mmol/L or vehicle (DMSO), which is further consistent with the current literature. 49,50 Fresh growth media with or without sorafenib was provided for 24-48-72 h and 1 week. MTS reagent (20 mL/well) was added to the cells followed by incubation for 4 hours in a 5% CO 2 humidified incubator at 37 C, and the absorbance was measured at 490 nm, at 0, 24, 48, and 74 hours, and after 1 week Q121 .…”

TM6SF2/PNPLA3/MBOAT7 loss-of-function genetic variants impact on NAFLD development and progression both in patients and in in vitro models

“…Therefore, after a day, cells were treated with either sorafenib at a final concentration of 5 mmol/L or vehicle (DMSO), which is further consistent with the current literature. 49,50 Fresh growth media with or without sorafenib was provided for 24-48-72 h and 1 week. MTS reagent (20 mL/well) was added to the cells followed by incubation for 4 hours in a 5% CO 2 humidified incubator at 37 C, and the absorbance was measured at 490 nm, at 0, 24, 48, and 74 hours, and after 1 week.…”

Application of graph models to the identification of transcriptomic oncometabolic pathways in human hepatocellular carcinoma

“…In colorectal cancer, the low expression of SPTLC1 leads to worse prognosis (40), in renal cell carcinoma, it inhibits cell proliferation (41) and in lymphoma patients, a mutation of SPTLC1 increasing its enzymatic activity, sensitized BCR-ABL tumors to imatinib (42). On the other hand, serum ceramides and sphingolipids such as S1P and SA1P are increased in patients with HCC but not in cirrhotic controls (43), and the blockade of sphingolipids in Huh7 and HepG2 cell lines led to increased susceptibility to sorafenib (44). More broadly, it has been described that sphingolipids are produced in higher amounts in cancer cells and that sphingosine-1-phosphate (S1P) intermediate promotes proliferation, migration and EMT (45) and regulates the interphase with other cells through the inhibition of sindecan 1 (46).…”