Protein expression signatures of the ING family in benign odontogenic epithelial lesions.

OBJECTIVES: This study analyzed the immunoexpression of ING proteins in benign odontogenic lesions and dental follicles (DF), assessing interrelationships and correlations with p53, Bcl-2 and Bax.

STUDY DESIGN: Twenty conventional ameloblastomas (AMB), 20 adenomatoid odontogenic tumors (AOT), 20 odontogenic keratocysts (OKC) and 10 DF were analyzed by immunohistochemistry for ING1-5, p53, Bcl-2, and Bax, considering cellular localization.

RESULTS: ING2 was higher in DF, OKC, and AMB versus AOT (p < .0001). ING3 was lower in AMB versus DF (p = .003), and ING4 was reduced in OKC and AMB versus DF, and lower in AMB versus AOT (p < .0001). Nuclear/nuclear-cytoplasmic ING was predominant in DF, and cytoplasmic/nuclear-cytoplasmic expression in odontogenic lesions, especially OKC and AMB. ING proteins showed strong interrelationships, particularly among nuclear-cytoplasmic ING1/3/4 in DF, AOT, and AMB, with some negative correlations for nuclear-cytoplasmic versus cytoplasmic compartments (p < .05). Significant correlations with apoptosis-related markers were limited. Hierarchical clustering identified 3 molecular clusters, associated with different tissue types (p < .0001), reflecting combined ING expression patterns and apoptosis-related proteins.

CONCLUSIONS: Distinct molecular signatures of ING protein expression in odontogenic lesions reveal nuclear loss and cytoplasmic redistribution in OKC and AMB, suggesting coordinated involvement of these proteins in odontogenic lesion pathogenesis.