Microarray analysis of slipped capital femoral epiphysis growth plates.

BACKGROUND: Microarray technology has been used to analyze gene expression in patients with and without slipped capital femoral epiphysis (SCFE). METHODS: Proximal femoral physis core biopsies from two patients with SCFE were compared with two control specimens from age-matched patients without SCFE. Extracted RNA from frozen ground samples was subjected to microarray analysis with data tests for statistical significance between SCFE and control tissues. RESULTS: Compared to controls, SCFE samples demonstrated significant up-regulation in gene expression pathways involving physiological defense and inflammatory responses and significant down-regulation in the regulation of cellular physiologic processes, cellular metabolic pathways, and skeletal development pathways including expression of aggrecan and type II collagen, genes affecting physeal structure and integrity. CONCLUSIONS: Up-regulation of inflammatory and immune response pathways in SCFE compared to controls relates to physeal mechanical displacement in SCFE. Globalized down-regulation of several other pathways suggests growth plate weakening. These novel microarray findings further define SCFE etiology.