RESUMEN
Tumors and cysts with odontogenic origin represent a family of lesions with specific histo-genetic and clinical characteristics. Among them, ameloblastomas are common benign neoplasms, predominantly detected in the anatomic areas of the jaws and also in the mandible and maxilla. Although they are characterized by a slow and stable growing pattern, a subset of them shows a tendency for local tissue invasiveness and partially increased recurrence rates after surgical excision. Furthermore, heat shock proteins (HSPs) are potentially implicated in ameloblastoma onset and progression. HSPs regulate the folding and refolding of proteins and are induced in response to oxidative stress. They are crucial members of the chaperone intracellular system and are categorized based on their molecular weight (i.e., HSP27, HSP60, HSP70, HSP90). In the current review, we describe HSPs origin and function, focusing on their deregulation mechanisms and impact predominantly on ameloblastomas and also on inflammatory and developmental odontogenic cystic lesions.
RESUMEN
BACKGROUND/AIM: Odontogenic cysts belong to a type of lesions with endodontic origin that in some cases mimic even aggressive odontogenic tumors sharing with them similar radiographic features. Periapical cysts (PCs) belong to the inflammatory odontogenic cysts sub-category and rarely squamous cell carcinoma arises from their hyperplastic/ dysplastic epithelia. This study aimed to explore the impact of cluster differentiation 34 (CD34) protein expression combined with micro vessel density (MVD) on PCs. MATERIALS AND METHODS: Forty-eight (n=48) archival, formalin-fixed, and paraffin-embedded PC tissue specimens were included in the study. Immunohistochemistry (IHC) was performed in the corresponding tissue sections using an anti- CD34 antibody. CD34 expression levels and also MVD in the examined cases were measured by implementing a digital image analysis protocol. RESULTS: CD34 over-expression (moderate to high staining intensity levels) were detected in 29/48 (60.4%) cases, whereas the rest of them (19/48-39.6%) were characterized by low levels of expression. Extended MVD was identified in 26/48 (50.1%) cases correlated with CD34 over-expression, epithelial hyperplasia (p-value=0.001), and marginally with inflammatory infiltration level in the examined lesions (p-value=0.056). CONCLUSION: CD34 over-expression combined with increased MVD is associated with a neoplastic-like (hyperplastic) phenotype in PCs as a result of increased neo-angiogenic activity. These histopathological characteristics rarely form an eligible substrate for squamous cell carcinoma onset in untended cases.