Inhibitory Effects of Gabapentin on the Proliferation and Cell Motility of Hepatocellular Carcinoma Cells

Background: Gabapentin, originally an antiepileptic agent, was found to have anti-cancer activity on multiple cancer cells. However, its effects on hepatocellular carcinoma (HCC) and associated molecular mechanisms are unclear. Objectives: In this study, we investigated the anti-cancer effects of gabapentin against HCC cells in vitro and in vivo. Methods: Human HCC cells were inoculated with various levels of gabapentin for 24 and 48 h. We utilized the MTT assay to detect the proliferation of HCC cells after gabapentin treatment. The effect of gabapentin on the migration of HCC cells was detected by transwell migration assay. We established a model of subcutaneously transplanted HCC in nude mice and observed the impact of gabapentin on HCC cell tumorigenicity in vivo. The changes in RNA expression in gabapentin-treated HCC cells were evaluated by RNA sequencing analysis, and the results were analyzed and further validated by qRT-PCR. Results: Gabapentin significantly inhibited the proliferation of a variety of human HCC cells in a time- and dose-dependent approach. After treatment with 10 mM gabapentin for 12 h, the transendothelial migration of HCC cells via membrane remarkably reduced. Three weeks after the hypodermic transplanting of HCC in nude mice with Huh7 cell line, the gabapentin-treated group had a dramatic decrease in mean tumor volume and weight relative to the controls. Relative to the normal Huh7 cell line, the results of RNA sequencing of Huh7 cells treated with gabapentin for 24 h showed the differential enrichment of genes involved in "energy metabolism", "cancers", "signal transduction", and "folding, sorting, and degradation". The genes CDH11 and ARHGAP15 related to cell migration were further verified by qRT-PCR. Conclusions: Our results suggested that gabapentin has an inhibitory effect on the growth, migration, and tumor formation of hepatoma cells, and the mechanism of gabapentin’s inhibition on HCC cells may be related to some signaling pathways, which will lay a foundation for the future studies on branched-chain aminotransferase 1 (BCAT1) as a target for HCC treatment.