Salsalate improves the anti-tumor efficacy of Lenvatinib in MASH-driven hepatocellular carcinoma.

Background & Aims

Metabolic dysfunction associated steatohepatitis (MASH) is a growing contributor of hepatocellular carcinoma (HCC) worldwide. The complex microenvironment of these tumors, characterized by metabolic dysfunction, hypoxia, steatosis, and fibrosis limits, the effectiveness of standard of care therapies such as the multi-tyrosine kinase inhibitor Lenvatinib. Salsalate, a rheumatoid arthritis therapy that stimulates AMP-activated protein kinase (AMPK) enhances fatty acid oxidation and reduces de-novo lipogenesis, fibrosis and cell proliferation pathways. We hypothesise that addition of Salsalate could improve the efficacy of Lenvatinib in MASH-HCC.

Methods

We assessed the efficacy of combination therapy using clinically relevant concentrations of Lenvatinib and Salsalate in human HCC cell models, orthotopic xenograft and MASH-HCC mouse models. Additionally, in vitro assays assessing fat oxidation and lipogenesis, protein immunoblotting and RNA-sequencing were employed to understand mechanisms at play.

Results

Combined Lenvatinib plus Salsalate synergistically suppressed proliferation and clonogenic survival in cells (p≤0.0001), prolonged survival in an orthotopic xenograft model (p=0.02) and reduced angiogenesis, fibrosis and steatosis (p≤0.05) in a MASH-HCC model. These effects were associated with activation of AMPK and inhibition of the mTOR-HIF1α and Erk1/2 signaling pathways. RNA-sequencing analysis in both Hep3B cells and livers of the MASH-HCC mouse model revealed that Salsalate enhanced mitochondria fatty acid oxidation and suppressed fibrosis and cell cycle progression while Lenvatinib reduced angiogenesis with regulatory network analysis suggesting a potential role for Activating Transcription Factor 3 and ETS-proto-oncogene-1.

Conclusions

These data indicate that combining Lenvatinib and Salsalate which exert distinct effects leading to improvements in the liver microenvironment (steatosis, angiogenesis and fibrosis) and inhibition of tumor proliferation, may have therapeutic potential for MASH driven HCC.