Turkish Journal of Medical Sciences
Abstract
Background/aim: Diclofenac (Diclo), a widely used nonsteroidal antiinflammatory drug, has emerged as a potential candidate for drug repurposing in oncology, with reported anticancer effects extending beyond cyclooxygenase (COX) inhibition, including modulation of tumor metabolism. This study investigated the antiproliferative and glycolysis-associated effects of Diclo in MCF-7 breast cancer cells, alone and in combination with docetaxel (Doc) or 5-fluorouracil (5-FU).
Materials and methods: Cell viability was assessed using the sulforhodamine B (SRB) assay. To evaluate metabolic alterations, glucose uptake and lactate release were quantified following treatment. In addition, Triosephosphate Isomerase (TPI) protein levels and Lactate Dehydrogenase (LDH) activity were measured to explore potential modulation of glycolytic pathways.
Results: Diclo reduced MCF-7 viability in a dose-dependent manner (IC50: 78.37 μg/mL). Combining Diclo with Doc or 5-FU enhanced cytotoxicity compared with single agents. Although Diclo alone did not significantly change glucose uptake, Diclo+Doc and Diclo+5- FU significantly decreased glucose uptake, and lactate release was reduced, particularly in Diclo-containing treatments. Diclo decreased TPI levels, and Diclo-based combinations further reduced TPI. LDH activity decreased with Diclo, while certain combinations produced divergent LDH responses, suggesting treatment-dependent effects on lactate metabolism and/or cellular stress.
Conclusion: Diclo potentiated the cytotoxic effects of Doc and 5-FU and was associated with reduced glycolytic readouts and decreased TPI in MCF-7 cells, supporting a potential role for Diclo as a metabolic modulator in breast cancer combination therapy.
Author ORCID Identifier
GONCA TUNA: 0000-0003-2567-8056
ELİF ERTÜRK: 0000-0001-7668-796X
AYŞEN SAĞNAK: 0009-0004-0929-5236
FERDA ARI: 0000-0002-6729-7908
DOI
10.55730/1300-0144.6373
Keywords
breast cancer, Diclofenac, glycolysis, triosephosphate isomerase
First Page
1287
Last Page
1295
Publisher
The Scientific and Technological Research Council of Türkiye (TÜBİTAK)
Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
TUNA, G, ERTÜRK, E, SAĞNAK, A, & ARI, F (2026). Repurposing diclofenac for combination therapy: targeting the Warburg effect to enhance breast cancer treatment . Turkish Journal of Medical Sciences 56 (4): 1287-1295. https://doi.org/10.55730/1300-0144.6373