Biomarcadores salivares de remodelação óssea e reparo tecidual em pacientes irradiados em região de cabeça e pescoço

• Ano de defesa: 2019
• Autor(a) principal: Eduardo Morato de Oliveira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; Programa de Pós-Graduação em Odontologia; UFMG
• Palavras-chave em Português: Saliva; Proteínas salivares; Radioterapia; Remodelação óssea; Proteínas e Peptídeos Salivares; Remodelação Óssea; Biomarcadores
• Link de acesso: http://hdl.handle.net/1843/30004

Head and neck cancer treatment involves in addition to surgery, chemotherapy and radiotherapy. Radiotherapy in head and neck region is harmful also to the normal tissue and the oral cavity that is very susceptible by the radiation direct and indirect effects, and it can affect tissue repair, notably in the salivary glands and bone metabolism. As consequences may occur hyposalivation and xerostomia, dysgeusia, oral infections, aggressive dental caries, mucositis, trismus and osteoradionecrosis. Chemotherapy may be associated with radiotherapy in the treatment of head and neck malignant neoplasms. This therapeutic modality can also trigger some adverse effects such as intense inflammation of the digestive system mucosa, hyposalivation, difficulty in swallowing and weight loss. Saliva presents a simple sampling and handling, and can be used for the investigation of biomarkers. The aim of this study was to compare salivary biomarkers related to bone remodelling and tissue repair in head and neck irradiated patients and non-irradiated patients. This is a crosssectional prospective study. Patients treated by radiotherapy for head and neck cancer from April to November 2018 were selected. Healthy individuals never exposed to radiotherapy composed the comparison group, paired by sex and age. Exclusion criteria applied. Total unstimulated saliva was collected. RANK, RANKL, OPG, EGF, VEGF e MMP-9 concentration was assessed using ELISA method. Statistics analysis was performed on SPSS® 19.0 e GraphPad Prism®7.0 softwares. Statistical significance was set at p <0.05. The salivary volume was significantly lower in the irradiated patients. Salivary concentration of RANK, OPG, and VEFG did not differ from patients (n=29) and controls (p<0.05). EGF (p=0.000) e MMP-9 (p=0.014) were higher in control group than in patients. RANK-L dosage was higher in control group, with a marginal p-value (0.051). When comparing the results of the patients that received only RT (n=13) with controls, the EGF (p=0.003) e MMP-9 (p=0.031) were significantly higher in the control group, and the other biomarkers (RANK, RANK-L, OPG and VEGF) did not show statistical significant difference. The comparison between patients tread with RT and chemotherapy (n=16) revealed statistical significant difference only for EGF dosage (p=0.031). In conclusion, head and neck radiation therapy decreases the salivary levels of EGF and MMP-9, but not of RANK, OPG and VEGF. RANKL shows a tendency to decrease with radiotherapy. EGF and MMP-9 deficiency in the saliva of irradiated patients may be related to the deleterious effects of ionizing radiation in the oral cavity.