@article{3088066,
    title = "Expression profile of osteoprotegerin, RANK and RANKL genes in the femoral head of patients with avascular necrosis",
    author = "Samara, S. and Dailiana, Z. and Chassanidis, C. and Koromila, T. and Papatheodorou, L. and Malizos, K.N. and Kollia, P.",
    journal = "Experimental and Molecular Pathology",
    year = "2014",
    volume = "96",
    number = "1",
    pages = "9-14",
    publisher = "Academic Press Inc.",
    issn = "0014-4800, 1096-0945",
    doi = "10.1016/j.yexmp.2013.10.014",
    keywords = "messenger RNA;  osteoclast differentiation factor;  osteoprotegerin;  receptor activator of nuclear factor kappa B, adult;  aged;  article;  avascular necrosis;  bone remodeling;  clinical article;  controlled study;  female;  femur head necrosis;  gene expression profiling;  gene identification;  gene location;  genetic association;  human;  human cell;  human tissue;  male;  OPG gene;  protein determination;  protein localization;  quantitative study;  rank gene;  RANKL gene;  real time polymerase chain reaction;  tissue distribution;  upregulation;  Western blotting, Avascular necrosis of the bone;  OPG;  Osteoblasts;  Osteoclasts;  RANK;  RANKL, Adult;  Aged;  Blotting, Western;  Female;  Femur Head Necrosis;  Humans;  Male;  Middle Aged;  Osteoprotegerin;  RANK Ligand;  Real-Time Polymerase Chain Reaction;  Receptor Activator of Nuclear Factor-kappa B;  Reverse Transcriptase Polymerase Chain Reaction;  RNA, Messenger;  Young Adult",
    abstract = "Introduction: Femoral head avascular necrosis (AVN) is a recalcitrant disease of the hip that leads to joint destruction. Osteoprotegerin (OPG), Receptor Activator of Nuclear Factor kappa-B (RANK) and RANK ligand (RANKL) regulate the balance between osteoclasts-osteoblasts. The expression of these genes affects the maturation and function of osteoblasts-osteoclasts and bone remodeling. In this study, we investigated the molecular pathways leading to AVN by studying the expression profile of OPG, RANK and RANKL genes. Material and methods: Quantitative Real Time-PCR was performed for evaluation of OPG, RANK and RANKL expression. Analysis was based on parallel evaluation of mRNA and protein levels in normal/necrotic sites of 42 osteonecrotic femoral heads (FHs). OPG and RANKL protein levels were estimated by western blotting. Results: The OPG mRNA levels were higher (insignificantly) in the necrotic than the normal site (p. >. 0.05). Although the expression of RANK and RANKL was significantly lower than OPG in both sites, RANK and RANKL mRNA levels were higher in the necrotic part than the normal (p. <. 0.05). Protein levels of OPG and RANKL showed no remarkable divergence. Conclusions: Our results indicate that differential expression mechanisms for OPG, RANK and RANKL that could play an important role in the progress of bone remodeling in the necrotic area, disturbing bone homeostasis. This finding may have an effect on the resulting bone destruction and the subsequent collapse of the hip joint. © 2013."
}