Document Type
Article
Publication Date
6-2017
Abstract
Primary effusion lymphoma (PEL) is a largely incurable malignancy of B cell origin with plasmacytic differentiation. Here, we report the identification of a highly effective inhibitor of PEL. This compound, 6-ethylthioinosine (6-ETI), is a nucleoside analog with toxicity to PEL in vitro and in vivo, but not to other lymphoma cell lines tested. We developed and performed resistome analysis, an unbiased approach based on RNA sequencing of resistant subclones, to discover the molecular mechanisms of sensitivity. We found different adenosine kinase–inactivating (ADK-inactivating) alterations in all resistant clones and determined that ADK is required to phosphorylate and activate 6-ETI. Further, we observed that 6-ETI induces ATP depletion and cell death accompanied by S phase arrest and DNA damage only in ADK-expressing cells. Immunohistochemistry for ADK served as a biomarker approach to identify 6-ETI–sensitive tumors, which we documented for other lymphoid malignancies with plasmacytic features. Notably, multiple myeloma (MM) expresses high levels of ADK, and 6-ETI was toxic to MM cell lines and primary specimens and had a robust antitumor effect in a disseminated MM mouse model. Several nucleoside analogs are effective in treating leukemias and T cell lymphomas, and 6-ETI may fill this niche for the treatment of PEL, plasmablastic lymphoma, MM, and other ADK-expressing cancers.
Recommended Citation
Nayar U, Sadek J, Reichel J, et al. Identification of a nucleoside analog active against adenosine kinase–expressing plasma cell malignancies. J Clin Invest. 2017;127(6):2066–2080. doi: 10.1172/JCI83936.
Copyright
American Society for Clinical Investigation
Included in
Cancer Biology Commons, Medicinal and Pharmaceutical Chemistry Commons, Nucleic Acids, Nucleotides, and Nucleosides Commons, Other Pharmacy and Pharmaceutical Sciences Commons, Pharmaceutics and Drug Design Commons, Therapeutics Commons
Comments
This article was originally published in Journal of Clinical Investigation, volume 127, issue 6, in 2017. DOI:10.1172/JCI83936.