Avaliação imunoistoquímica das galectinas -1, -3 e -7 em ameloblastoma e tumor odontogênico adenomatoide

Abstract

Background: Ameloblastoma (AM) and adenomatoid odontogenic tumor (AOT) are benign odontogenic tumors with ephitelial origin, but exhibiting distinct clinical behavior. This fact leads to development of research that try to better understand the possible differences in the pathogenesis and biological behavior of these lesions. Galectins are proteins involved in various pathological mechanisms of the oral cavity, however, until the presente moment, its role in odontogenic tumors is still poorly elucidated. Objective: To evaluate the immunoexpression of galectins -1, -3 and -7 in a series of cases of AM and AOT, comparing it with clinicomorphological parameters. Material and Methods: A total of 31 cases of AM and 20 cases of AOT were analyzed in a retrospective and cross-sectional study. Clinical data (sex, age, anatomical location, radiographic aspects and primary or recurrent lesion) were collected from biopsy request forms. In the morphological study, classification proposed by the WHO (2017) was considered. For the immunohistochemical study, it were established percentages of imunopositives cells to galectins -1, -3 and -7, considering differents cell compartments, in 10 microscopy fields in the parenchyma of AM and AOT. In the stroma, absence/presence of galectin immunoexpression was considered. Data obtained were submitted to statistical analysis using the Mann-Whitney and Fisher’s exact tests (p<0.05). Results: In morphological analysis and clinicoradiographic was observed a higher frequency of AM conventional (n=24; 77.4%), and AOT follicular (n=12; 60.0%). In immunohistochemical analysis was observed higher nuclear immunoexpression of galectins -1 (p<0.001), -3 (p<0.001), and -7 (p<0.001) in AM. There was significant difference of immunoexpression of nuclear galectin-1 with AM recurrent (p<0.001), cytoplasmatic galectin-1 with AM primary (p=0.028), nuclear galectin-3 with AM symptomatic (p=0.014), nuclear galectin-7 with AM conventional (p=0.040), and cytoplasmatic galectin-7 with AM symptomatic (p=0.021). AOTs showed higher cytoplasmatic immunoexpression of galectins -3 (p=0.003) and -7 (p=0.015), and higher nuclear/ cytoplasmatic immunoexpression of galectins -1 (p=0.011) and -3 (p=0.004). There was significant difference of immunoexpression of nuclear galectin-1 with AOT mandibular. (p=0.009). In tumour stroma, AM showed higher expression of galectin-1 than AOT (p=0.007). Conclusions: Expressive marking of galectins -1, -3 and -7 in AM and AOT, indicates your participation on pathogenesis of these tumors. In general, different immunoexpression of galectins according to cell compartments, may partly justify the differences in the biological behavior of these lesions.