Banca de QUALIFICAÇÃO: DÁUREA ADÍLIA CÓBE SENA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : DÁUREA ADÍLIA CÓBE SENA
DATE: 27/04/2022
TIME: 14:00
LOCAL: PLATAFORMA VIRTUAL
TITLE:

STUDY OF IMMUNOEXPRESSION OF PROTEINS INVOLVED IN THE EPITHELIAL-MESENCHYMAL TRANSITION IN SALIVARY GLAND TUMORS

KEY WORDS:

Salivary gland neoplasms, Epithelial/Mesenchymal Transition (TEM), Snail1, Twist1, E-cadherin, Vimentin, MMP-9, Myofibroblast.Immunohistochemistry.

PAGES: 90
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

Salivary gland tumors (SGT) have a low prevalence, comprising 3% of all head and neck tumors. Given this rarity, the events involved in malignant transformation, as well as in the progression of SGT, have often been the objective of many studies. One of the dynamics involved in the progression and invasion of different types of carcinomas is the epithelial mesenchymal transition. In this process, epithelial cells undergo transition to a mobile mesenchymal state, favoring invasion and metastasis. To acquire this phenotype, epithelial cells go through changes on genes expression and protein levels. There is a loss of expression of E-cadherin, whose protein is responsible for cell adhesion. Genes such as Twist1 and Snail are now expressed and encode E-cadherin repressor transcription factors. High levels of vimentin (VM), whose protein composes a cytoskeletal network which directs cell motility, are observed. In addition, myofibroblasts, activated stromal cells that express alpha smooth muscle actin (α-SMA), secrete matrix metalloproteinase nine (MMP-9), whose function is to degrade the extracellular matrix and facilitate the migration of tumor cells. Thus, the aim of this research is to evaluate and to compare the immunopositivity of these markers in SGT, as well as to correlate with clinicopathological parameters. It will be selected 20 cases of pleomorphic adenoma, 20 of adenoid cystic carcinoma, 20 of mucoepidermoid carcinoma, 10 of polymorphic adenocarcinoma, 10 of carcinoma ex-pleomorphic adenoma and 10 of epithelial-myoepithelial carcinoma. Subsequently, a semi-quantitative analysis will be performed in the tumor parenchyma for the E-cadherin, Snail and Twist1 markers. The expression intensity (EI) and the percentage of positive cells (PP) will be evaluated; the sum of these parameters will generate a score between 0 and 7. Cases with a score between 0 and 4 will be classified as low expression and those between 5 and 7, as high expression. The reactivity of α-SMA, VM and MMP-9 will be analyzed in the tumor stroma. α-SMA positive cells, excluding those delineating vessel walls, will be counted for each case in 10 high power fields (HPF) . The average of all cases will represent the cutoff to categorize cases as high or low expression for this marker. MMP-9 reactivity will be evaluated for EI and PP and categorized into 3 scores. These values will be multiplied and the cases with values between 0 and 3 will be considered as low expression and those between 6 and 9, high expression. VM reactivity will be evaluated qualitatively, using 4 scores according to the EI and whether the reaction is diffuse or focal. The results obtained will be submitted to statistical analysis with the aid of the Statistical Package for the Social Sciences program, considering a significance level of 5%.

BANKING MEMBERS:
Presidente - 346077 - LELIA BATISTA DE SOUZA
Externa ao Programa - 3218128 - AMANDA KATARINNY GOES GONZAGA
Externo à Instituição - LEORIK PEREIRA DA SILVA - UFCG