Head and neck radiotherapy does not increase gelatinase (metalloproteinase-2 and-9) expression or activity in teeth irradiated in vivo

Author(s)

Gomes-Silva, Wagner ; Prado Ribeiro, Ana Carolina ; de Castro Junior, Gilberto ; Salvajoli, Joao Victor ; Palmier, Natalia Rangel ; Lopes, Marcio Ajudarte ; Rocha, Marcelo Marques ; de Goes, Mario Fernando ; Brandao, Thais Bianca ; Santos-Silva, Alan Roger

• Document type: Journal article
• Source: ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY ORAL RADIOLOGY; v. 124, n. 2, p. 175-182, AUG 2017.
• Web of Science Citations: 2

Abstract

Objective. Recent studies suggested that head and neck radiotherapy increases active forms of matrix metalloproteinases (MMPs) in the dentin-enamel junction (DEJ), leading to enamel delamination and radiation-related caries. This study aimed to assess the expression and activity of the gelatinases MMP-2 and MMP-9 in the DEJ and dentin-pulp complex tissues of teeth irradiated in vivo. Study Design. Thirty-six teeth were studied, including 19 irradiated and 17 non-irradiated controls. In situ zymography was used to investigate the gelatinolytic activity in the micromorphologic components of enamel, DEJ, dentin-pulp complex, and caries. Immunohistochemical analysis was conducted on the demineralized samples to assess MMP-2 and MMP-9 expression levels in the DEJ, dentin-pulp complex components, and caries. Results. No statistically significant differences were detected between groups in gelatinolytic activity or in MMP-2 expression levels (P > .05). Odontoblast MMP-9 expression was reduced in the irradiated group (P = .02). Conclusions. The study rejected the hypothesis that MMP-2 and MMP-9 would be overexpressed or more activated in the DEJ and dentin-pulp complex of irradiated teeth. Direct effects of radiation should not be regarded as an independent factor for explaining radiation-related caries onset and progression. (AU)

• FAPESP's process: 12/06138-1 - A prospective study of radiation-induced trismus in patients with oral squamous cell carcinoma
• Grantee: Ana Carolina Prado Ribeiro e Silva
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/18402-8 - Evaluation of the direct effects of radiation on the enamel, dentin and dental pulp of head and neck cancer patients
• Grantee: Alan Roger dos Santos Silva
• Support Opportunities: Regular Research Grants