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Updated: Aug 23, 2026

HPLC-based Assay to Monitor Extracellular Nucleotide/Nucleoside Metabolism in Human Chronic Lymphocytic Leukemia Cells
11:29

HPLC-based Assay to Monitor Extracellular Nucleotide/Nucleoside Metabolism in Human Chronic Lymphocytic Leukemia Cells

Published on: July 20, 2016

The A3 adenosine receptor is highly expressed in tumor versus normal cells: potential target for tumor growth

Lea Madi1, Avivit Ochaion, Lea Rath-Wolfson

  • 1Can-Fite BioPharma Ltd., Kiryat-Matalon, Petach-Tikva, Israel.

Clinical Cancer Research : an Official Journal of the American Association for Cancer Research
|July 9, 2004
PubMed
Abstract

Insights

The adenosine A(3) receptor (A(3)AR) is highly expressed in primary and metastatic solid tumors. This suggests A(3)AR is a potential target for inhibiting tumor growth by down-regulating key cell proliferation factors.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Adenosine A(3) receptor (A(3)AR) activation inhibits tumor cell growth by down-regulating nuclear factor kappaB and cyclin D1.
  • Investigating A(3)AR expression levels in tumor versus normal tissues is crucial to determine its potential as a specific therapeutic target.

Purpose of the Study:

  • To survey A(3)AR expression in various tumor tissues compared to adjacent normal cells.
  • To evaluate the potential of A(3)AR as a specific target for tumor growth inhibition.

Main Methods:

  • Reverse transcription-PCR analysis of A(3)AR mRNA in paraffin-embedded tumor tissues and adjacent normal tissues or lymph node metastasis.
  • Western blot analysis of A(3)AR protein expression in fresh tumor samples and correlation with adjacent normal tissue.

Main Results:

  • A(3)AR mRNA expression was significantly higher in colon and breast carcinoma tissues compared to adjacent normal tissues.
  • Lymph node metastasis exhibited even higher A(3)AR mRNA levels than primary tumor tissue.
  • Protein analysis confirmed higher A(3)AR expression in 61% of colon and 78% of breast tumors versus adjacent normal tissue, associated with elevated nuclear factor kappaB and cyclin D1.

Conclusions:

  • High A(3)AR expression is a characteristic of both primary and metastatic solid tumors.
  • These findings, coupled with previous data, strongly support A(3)AR as a promising target for developing novel anti-tumor therapies.

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