Parecoxib decreases cellular growth and Bcl‐2 protein levels in primary cultures of keloid fibroblasts

: Keloids seem to overexpress cyclo-oxygenase-2 (COX-2), suggesting a role in its deregulated pathway in inducing an altered epithelial-mesenchymal interaction, which may be responsible for the overgrowth of dermal components resulting in scars or keloid lesions. This study aimed to evaluate the effect of Parecoxib, a COX-2 inhibitor, on cell growth in fibroblast primary cultures obtained from human keloid tissues. Tissue explants were obtained from patients who underwent intralesional excision of untreated keloids; central fractions were isolated from keloid tissues and used for establishing distinct primary cultures. Appropriate aliquots of Parecoxib, a COX-2 inhibitor were diluted to obtain the concentration used in the experimental protocols in vitro (1, 10 or 100 μM). Treatment with Parecoxib (at all concentrations) caused a significant decrease in cellular growth from 24 hours onwards, and with a maximum at 72 hours (P < .02). Moreover, at 72 hours Parecoxib significantly reduced cellular vitality. Parecoxib treatment also induced an increase in fragmented nuclei with a maximum effect at 100 μM and a significant decrease in Bcl-2 and an increase in activated caspase-3 protein levels at 72 hours compared with control untreated cultures. Our findings suggest a potential use of the COX-2 inhibitor, Parecoxib, as the therapy for keloids.