osteoprotegerin and Dentigerous-Cyst

Reduced expression of syndecan-1 (CD138), increased proliferation index, and modifications in the expression of the molecular RANK/RANKL/OPG triad are related to an intensified potential of aggressiveness and invasion of diverse tumors and cysts. The aim was to compare the expression of Ki-67, CD138, and the molecular triad RANK, RANKL, and OPG in odontogenic keratocysts (OKC), unicystic ameloblastomas (UA), and dentigerous cysts (DC).. Immunohistochemistry for Ki-67, CD138, RANK, RANKL, and OPG was performed in 58 odontogenic cystic lesions (22 OKC, 17 DC, and 19 UA).. A higher expression of Ki-67 was identified in OKC as compared to UA (. Higher RANKL expression together with the reduction on CD138 expression in UA could be linked to a greater invasive and destructive potential, while the increased proliferation rate observed in OKC could be related to its continuous intrabony growth. The expansion of DC does not seem to be related to such factors, justifying the different therapeutic approaches proposed for each of these entities.

Topics: Ameloblastoma; Biomarkers; Dentigerous Cyst; Gene Expression Regulation; Humans; Jaw Neoplasms; Ki-67 Antigen; Odontogenic Cysts; Osteoprotegerin; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Syndecan-1

The aim of the present study was to compare the immunohistochemical detection of receptor activator nuclear κB ligand (RANKL) and osteoprotegerin (OPG) in radicular cysts (RCs), dentigerous cysts (DCs), solid ameloblastomas (SAs), and keratocystic odontogenic tumors (KOTs).. A total of 20 RCs, 20 DCs, 20 KOTs, 14 dental follicles (DFs), and 18 SAs were evaluated by immunohistochemistry using anti-RANKL and anti-OPG antibodies. The analysis was quantitative, and the number of positive cells was counted in 10 microscopic high-power fields (400×).. The DFs, KOTs, and SAs showed higher expression of RANKL than did the RCs and DCs in the epithelium (P < .05). The epithelial expression of OPG was higher in the DFs, KOTs, RCs, and DCs than in the SAs (P < .05). The ratio of OPG less than RANKL was more frequent in SAs and OPG greater than RANKL in DCs (P < .05).. Our results have shown differences in RANKL and OPG detection in the odontogenic cysts and tumors studied. The higher RANKL and lower OPG detection in SA could play a role in bone resorption, compatible with the tumor's biologic behavior.

Topics: Ameloblastoma; Biomarkers, Tumor; Cell Count; Coloring Agents; Dental Sac; Dentigerous Cyst; Epithelial Cells; Humans; Immunohistochemistry; Odontogenic Cysts; Odontogenic Tumors; Osteoprotegerin; Radicular Cyst; RANK Ligand; Stromal Cells

Radicular (RC) and dentigerous cysts (DC) can show a range from little to quite extensive primary/secondary inflammation and it is possible that the variation seen in the fibrous capsule of these cysts might reflect differences in the osteolytic activity. Moreover, the presence of hemorrhagic areas in the fibrous capsule of DC could also contribute to the increase in osteolytic activity. The aim of this study was to compare immunohistochemical expression of nuclear factor κappaB (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG), vascular endothelial growth factor (VEGF) and angiogenic index in RC and DC.. These proteins were evaluated in 20 RC and DC by immunohistochemistry. Angiogenic index was determined by microvessel count (MVC) using anti-von Willebrand factor antibody.. RANK and RANKL were higher in DC than RC in fibrous capsule. RC showed higher expression of VEGF in the epithelium and capsule. DC exhibited higher MVC than RC.. Ours results suggest that RANK and RANKL play an important role in bone resorption in DC and the hemorrhagic areas in the capsule of DC could be explained by increased vessel's number. The higher VEGF expression in RC might be related to nature of these lesions, where the inflammatory process contributes significantly to these findings.

Topics: Bone Resorption; Cell Count; Cell Nucleus; Connective Tissue; Cytoplasm; Dentigerous Cyst; Epithelial Cells; Epithelium; Humans; Immunohistochemistry; Microvessels; Neovascularization, Pathologic; Osteoprotegerin; Radicular Cyst; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Stromal Cells; Vascular Endothelial Growth Factor A; von Willebrand Factor

Receptor activator of nuclear factor-κB (RANK), RANK ligand (RANKL) and osteoprotegerin (OPG) are members of the superfamily of ligands and receptors of tumour necrosis factor family involved in bone metabolism. The formation, differentiation and activity of osteoclasts are regulated by these proteins. To clarify the roles of osteoclast regulatory factors in cystic expansion of odontogenic cysts, expression of these proteins were analysed in radicular and dentigerous cysts.. The immunohistochemistry expression of these biomarkers were evaluated and measured in lining epithelium and fibrous capsule of the radicular (n=20) and dentigerous cysts (n=20).. A similar expression in lining epithelium was observed in the lesions. The fibrous capsule of dentigerous cyst showed a higher content of RANK-positive and RANKL-positive cells than fibrous capsule of radicular cyst. In the lining epithelium the RANKL/OPG ratio showed higher numbers of OPG-positive than RANKL-positive cells, whereas fibrous capsule of the cysts had a tendency to present a similar expression (OPG=RANKL).. Ours findings indicate the presence of RANK, RANKL and OPG in cysts. Moreover, increased expression of OPG compared to RANKL in the lining epithelium could contribute to the differential bone resorption activity in theses lesions.

Topics: Adolescent; Adult; Child; Dentigerous Cyst; Epithelium; Female; Humans; Immunohistochemistry; Male; Mandibular Diseases; Maxillary Diseases; Middle Aged; Osteoclasts; Osteoprotegerin; Radicular Cyst; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Young Adult

The aim of this study was to compare the expression of nuclear factor kappaB (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) in odontogenic epithelial tumors and dentigerous cysts.. The expression of these molecules was evaluated in solid/multicystic ameloblastomas (n = 12) and unicystic ameloblastomas (n = 8), keratocystic odontogenic tumors (n = 19), dentigerous cysts (n = 9), and dental follicles (n = 9) by immunohistochemistry.. In odontogenic epithelium, a similar expression of RANK, RANKL, and OPG was observed in all samples. With regard to stroma, the number of RANK-positive and RANKL-positive cells was higher in solid/multicystic ameloblastomas compared with dentigerous cysts. Dental follicles had lower numbers of RANK-positive, RANKL-positive, and OPG-positive cells than solid/multicystic ameloblastomas and keratocystic odontogenic tumors. The majority of solid/multicystic ameloblastomas (75%) and unicystic ameloblastomas (62.5%) had higher numbers of RANKL-positive than OPG-positive cells. In contrast, 62.4% of keratocystic odontogenic tumors and 100% of dentigerous cysts exhibited a higher content of OPG-positive than RANKL-positive cells.. Our results indicate differences in the RANK, RANKL, and OPG expression in odontogenic epithelial tumors. The imbalance of these factors could contribute to the differential bone/tooth resorption activity in these lesions.

Topics: Ameloblastoma; Cell Count; Dentigerous Cyst; Epithelial Cells; Gene Expression; Humans; Jaw Neoplasms; NF-kappa B; Odontogenic Tumors; Osteolysis; Osteoprotegerin; RANK Ligand; Root Resorption; Statistics, Nonparametric; Stromal Cells

RANKL (receptor activator of nuclear factor kappaB ligand) promotes osteoclast differentiation, stimulates osteoclast activity, and prolongs osteoclast survival and adherence to bone. Abnormalities of the RANKL/RANK/osteoprotegerin system have been implicated in a range of diseases, including osteoporosis. To date, no work has been done in osteolytic lesions of the facial skeleton. In this study, specimens of ameloblastomas, dentigerous cysts, odontogenic keratocysts, and radicular cysts were subjected to immunohistochemical analysis for RANKL and tartrate-resistant acid phosphatase (TRAP). Immunofluorescence staining for TRAP was visualized under confocal microscopy. All specimens demonstrated distinct positive immunoreactivity to RANKL and TRAP. The TRAP-positive cells also stained with in situ hybridization for human calcitonin receptor, a definitive marker for osteoclasts. Mononuclear pre-osteoclasts were observed to migrate from blood to the connective tissue stroma and multinucleate toward the bone surface. It can be concluded that RANKL plays a role in bone resorption in osteolytic lesions of the facial skeleton.

Topics: Acid Phosphatase; Ameloblastoma; Dentigerous Cyst; Facial Bones; Glycoproteins; Humans; Immunohistochemistry; In Situ Hybridization; Isoenzymes; Jaw Neoplasms; Odontogenic Cysts; Osteolysis; Osteoprotegerin; Radicular Cyst; Receptors, Calcitonin; Receptors, Cytoplasmic and Nuclear; Receptors, Tumor Necrosis Factor; Signal Transduction; Tartrate-Resistant Acid Phosphatase