Celecoxib induces adipogenic differentiation of hemangioma-derived mesenchymal stem cells through the PPAR-γ pathway in vitro and in vivo

Infantile hemangioma (IH) is a benign tumor that produces a permanent scar or a mass of fibro-fatty tissue after involution in 40-80% of cases. Celecoxib is an inhibitor of cyclooxygenase-2 (COX-2), and can inhibit angiogenesis and fibrosis. The present study aimed to clarify whether celecoxib is able to induce tumor regression with minimal side effects. For that purpose, the regulation of celecoxib in the involution of IH was investigated in an IH model. Hemangioma-derived mesenchymal stem cells (Hem-MSCs) were isolated from proliferating specimens, and an IH model was established by injecting these cells into nude mice. Celecoxib was administered in vitro and in vivo. Oil Red O staining and reverse transcription-quantitative-PCR were used to detect the adipogenic differentiation of Hem-MSCs. Histologic analysis and immunohistochemical staining of the tumor xenografts were performed to investigate the pathological evolution of the tumor. The results showed that celecoxib inhibited the proliferation and induced the adipogenic differentiation of Hem-MSCs in vitro. In vivo, adipocytes were only present in the celecoxib group at week 4, while a larger number of fibroblasts and collagenous fibers could be observed in the basic fibroblast growth factor group. Therefore, celecoxib may be a potential agent used for IH treatment by inducing adipogenesis and inhibiting fibroblast formation.