Anti‐tumor effects of a nonsteroidal anti‐inflammatory drug zaltoprofen on chondrosarcoma via activating peroxisome proliferator‐activated receptor gamma and suppressing matrix metalloproteinase‐2 expression

Surgical resection is the only treatment for chondrosarcomas, because of their resistance to chemotherapy and radiotherapy; therefore, additional strategies are crucial to treat chondrosarcomas. Peroxisome proliferator‐activated receptor gamma (PPAR γ) is a ligand‐activated transcription factor, which has been reported as a possible therapeutic target in certain malignancies including chondrosarcomas. In this study, we demonstrated that a nonsteroidal anti‐inflammatory drug, zaltoprofen, could induce PPAR γ activation and elicit anti‐tumor effects in chondrosarcoma cells. Zaltoprofen was found to induce expressions of PPAR γ mRNA and protein in human chondrosarcoma SW1353 and OUMS27 cells, and induce PPAR γ‐responsible promoter reporter activities. Inhibitory effects of zaltoprofen were observed on cell viability, proliferation, migration, and invasion, and the activity of matrix metalloproteinase‐2 (MMP2); these effects were dependent on PPAR γ activation and evidenced by silencing PPAR γ. Moreover, we showed a case of a patient with cervical chondrosarcoma (grade 2), who was treated with zaltoprofen and has been free from disease progression for more than 2 years. Histopathological findings revealed enhanced expression of PPAR γ and reduced expression of MMP2 after administration of zaltoprofen. These findings demonstrate that zaltoprofen could be a promising drug against the malignant phenotypes in chondrosarcomas via activation of PPAR γ and inhibition of MMP2 activity.