Upregulated expression of PERK in spinal ligament fibroblasts from the patients with ossification of the posterior longitudinal ligament

Purpose Molecular mechanism of ossification of the posterior longitudinal ligament (OPLL) remains unclear. This study was to investigate different expressions of PERK between the spinal ligament fibroblasts from OPLL patients and non-OPLL patients, and demonstrate knockdown of PERK protein expression by RNA interference inhibiting expression of osteocalcin (OCN), alkaline phosphatase (ALP), and type I collagen (COL I) in the cells from OPLL patients.