Title: Nucleoside-catabolizing enzymes in mycoplasma-infected tumor cell cultures compromise the cytostatic activity of the anticancer drug gemcitabine
Authors: Vande Voorde, Johan ×
Sabuncuo─člu, Suna
Noppen, Sam
Hofer, Anders
Ranjbarian, Farahnaz
Fieuws, Steffen
Balzarini, Jan
Liekens, Sandra #
Issue Date: May-2014
Publisher: American Society for Biochemistry and Molecular Biology
Series Title: Journal of Biological Chemistry vol:289 issue:19 pages:13054-65
Article number: 10.1074/jbc.M114.558924
Abstract: The intracellular metabolism and cytostatic activity of the anticancer drug gemcitabine (2',2'-difluoro-2'-deoxycytidine; dFdC) was severely compromised in Mycoplasma hyorhinis-infected tumor cell cultures. Pronounced deamination of dFdC to its less cytostatic metabolite 2',2'-difluoro-2'-deoxyuridine was observed, both in cell extracts and spent culture medium (i.e. tumor cell-free but mycoplasma-containing) of mycoplasma-infected tumor cells. This indicates that the decreased antiproliferative activity of dFdC in such cells is attributed to a mycoplasma cytidine deaminase causing rapid drug catabolism. Indeed, the cytostatic activity of gemcitabine could be restored by the co-administration of tetrahydrouridine (a potent cytidine deaminase inhibitor). Additionally, mycoplasma-derived pyrimidine nucleoside phosphorylase (PyNP) activity indirectly potentiated deamination of dFdC: the natural pyrimidine nucleosides uridine, 2'-deoxyuridine and thymidine inhibited mycoplasma-associated dFdC deamination but were efficiently catabolized (removed) by mycoplasma PyNP. The markedly lower anabolism and related cytostatic activity of dFdC in mycoplasma-infected tumor cells was therefore also (partially) restored by a specific TP/PyNP inhibitor (TPI), or by exogenous thymidine. Consequently, no effect on the cytostatic activity of dFdC was observed in tumor cell cultures infected with a PyNP-deficient Mycoplasma pneumoniae strain. Because it has been reported that some commensal mycoplasma species (including M. hyorhinis) preferentially colonize tumor tissue in cancer patients, our findings suggest that the presence of mycoplasmas in the tumor microenvironment could be a limiting factor for the anticancer efficiency of dFdC-based chemotherapy. Accordingly, a significantly decreased antitumor effect of dFdC was observed in mice bearing M. hyorhinis-infected murine mammary FM3A tumors compared with uninfected tumors.
ISSN: 0021-9258
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Laboratory of Virology and Chemotherapy (Rega Institute)
Leuven Biostatistics and Statistical Bioinformatics Centre (L-BioStat)
× corresponding author
# (joint) last author

Files in This Item:
File Description Status SizeFormat
2014080.pdf Published 3565KbAdobe PDFView/Open Request a copy

These files are only available to some KU Leuven Association staff members


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science