RESUMO
Mucoepidermoid carcinoma (MEC) is the most common tumor in the salivary glands, often presenting with recurrence and metastasis due to its high invasive capacity. Metallothionein (MT), a zinc storage protein that supplies this element for protease activity, is probably related to mucoepidermoid carcinoma behavior. This prompted us to characterize a cell line derived from mucoepidermoid carcinoma and to correlate metallothionein expression with transforming growth factor-α (TGF-α), tumor necrosis factor-α (TNF-α) and matrix metalloproteinases (MMPs). Transcriptomic analysis and cytogenetic assays were performed to detect the expression of genes of interest and cellular chromosomal alterations, respectively. MEC cells with a depleted metallothionein 2A (MT2A) gene were subjected to Western blot to correlate metallothionein expression with growth factors and MMPs. Additionally, cells with depleted MT were subjected to migration and invasion assays. The transcriptomic study revealed reads mapped to cytokeratins 19 and AE1/AE3, α-smooth muscle actin, vimentin, and fibronectin. Cytogenetic evaluation demonstrated structural and numerical alterations, including the translocation t(11;19)(q21;p13), characteristic of MEC. Metallothionein depletion was correlated with the decreased expression of TGF-α and MMP-9, while TNF-α protein levels were augmented. Migration and invasion activity were diminished after metallothionein silencing. Our findings suggest an important role of MT in MEC invasion, through the regulation of proteins involved in this process.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Mucoepidermoide/patologia , Transição Epitelial-Mesenquimal , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Metaloproteinases da Matriz/metabolismo , Metalotioneína/metabolismo , Biomarcadores Tumorais/genética , Carcinoma Mucoepidermoide/genética , Carcinoma Mucoepidermoide/metabolismo , Humanos , Técnicas In Vitro , Metaloproteinases da Matriz/genética , Metalotioneína/genética , Células Tumorais CultivadasRESUMO
The association between fibrous dysplasia (FD) and fractures is very rare. This paper reports the case of a zygomaticomaxillary complex fracture in a bone affected by FD, a 29-year-old man who was involved in a bicycle accident and who subsequently presented with a zygomaticomaxillary complex fracture. Computed tomography revealed multiple fractures of the left zygomaticomaxillary complex with dysplastic bone alterations. Fracture lines occurred near transitional areas between the lesion and healthy bone. The patient was treated through an intraoral approach by an open reduction and internal fixation procedure, using a titanium miniplate and screws. An incisional biopsy was performed through the maxillary sinus to confirm the diagnosis of FD. After 12 months of follow-up, there were no postoperative complications. This paper reports a rare association thought to be caused by irregular trabecular bone deposition, which increases bone thickness/resiliency and thus increases its clinical fracture resistance.