Adenosine Receptor 3 in Liver Cancer: Expression Variability, Epigenetic Modulation, and Enhanced Histone Deacetylase

Louise Kaldjob-Heinrich1, Sandro Nuciforo2,3, Steffen Lemke4,5

  • 1Department Internal Medicine I, Eberhard-Karls University, Tuebingen, Germany.

Gastro Hep Advances
|February 6, 2025
PubMed
Abstract

Insights

Novel liver cancer treatments targeting Adenosine A3 receptor (ADORA3) show promise. Namodenoson, an ADORA3 agonist, combined with epigenetic drugs, demonstrated significant anti-cancer effects in hepatocellular carcinoma and cholangiocarcinoma models.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Primary liver cancer, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), has limited treatment options.
  • Adenosine A3 receptor (ADORA3) signaling is a potential therapeutic target.
  • Namodenoson, an ADORA3 agonist, has shown early promise in HCC clinical trials.

Purpose of the Study:

  • To investigate ADORA3 expression patterns in liver cancer.
  • To elucidate the mechanisms of action of ADORA3 agonists.
  • To evaluate combination therapies involving ADORA3 agonists for HCC and CCA.

Main Methods:

  • Patient-derived tissue microarrays and RNA-sequencing were used to assess ADORA3 expression.
  • Cellular responses to ADORA3 stimulation and combination treatments were studied in HCC/CCA cell lines and patient-derived organoids (PDOs).
  • Genome-wide RNA-Seq, mRNA analysis, and DigiWest protein profiling were performed.

Main Results:

  • ADORA3 expression varied significantly in HCC and CCA tumors, with higher expression in nonmalignant tissues.
  • The ADORA3 agonist Namodenoson exhibited antiproliferative effects in cancer cell lines and PDOs, dependent on ADORA3.
  • Combination treatments with ADORA3 agonists and histone deacetylase inhibitors enhanced antiproliferative effects, suggesting epigenetic modulation.

Conclusions:

  • ADORA3 expression levels can potentially stratify patients for clinical studies in HCC and CCA.
  • Namodenoson's epigenetic effects indicate that epigenetic drugs are promising partners for combination therapy.
  • Targeting ADORA3 signaling offers a novel therapeutic strategy for liver cancer, particularly in combination regimens.

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