HLA-G Is Differentially Expressed in Thyroid Tissues

Autor(es)

de Figueiredo Feitosa, Nathalie Lobo ^[1] ; de Oliveira Crispim, Janaina Cristina ^[2] ; Zanetti, Bruna Riedo ^[3] ; Ribeiro Magalhaes, Patricia Kunzle ^[1] ; Soares, Christiane Pienna ^[4] ; Soares, Edson Garcia ^[3] ; Neder, Luciano ^[3] ; Donadi, Eduardo Antonio ^[5] ; Zanini Maciel, Lea Maria ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Internal Med, Div Endocrinol & Metab, BR-14049900 Sao Paulo - Brazil

^[2] Univ Fed Rio Grande do Norte, Sch Pharmaceut Sci, Dept Clin & Toxicol Anal, BR-59072970 Natal, RN - Brazil

^[3] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Pathol, BR-14049900 Sao Paulo - Brazil

^[4] Univ Sao Paulo, Sch Pharmaceut Sci, Dept Clin Anal, BR-14049900 Sao Paulo - Brazil

^[5] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Internal Med, Div Clin Immunol, BR-14049900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: THYROID; v. 24, n. 3, p. 585-592, MAR 1 2014.
• Citações Web of Science: 12

Resumo

Background: HLA-G is a nonclassical major histocompatibility complex molecule that has well-recognized immunomodulatory properties. The expression of HLA-G in tumor cells has been considered to be detrimental, permitting tumor spreading and decreased survival. We evaluated the expression of HLA-G in histologically normal thyroid tissue, goiter, and benign and malignant thyroid tumors, and studied the relationship between HLA-G expression and patient clinical variables. Patients and Methods: The immunohistochemistry expression of HLA-G was performed on 72 specimens of papillary thyroid carcinoma (PTC), 19 follicular thyroid carcinomas (FTC), 22 follicular adenomas (FA), 22 colloid goiters (CG), and 14 histologically normal thyroid glands (NT). The percentage of HLA-G staining was graded from absent (-) to intense (+++). Results: HLA-G was faintly expressed in areas of hyperplasia in NT and CG. In PTC, FTC, and FA, the percentage of cell staining was significantly higher than in NT and CG (p<0.001 for each comparison). The tumor area with HLA-G expression was greater in FTC (p=0.0059) and PTC (p=0.0330) compared to FA. According to the magnitude of HLA-G staining, PTC tumors >1 cm exhibited increased HLA-G staining when compared to smaller tumors (p=0.03). Aggressive histologic subtypes of PTC have a higher median stained tumor area. No association was found between HLA-G expression and tumoral staging or patient disease-free survival. Conclusions: The gradual increase of HLA-G expression from hyperplasia to carcinomas, and the association of strong HLA staining with some variables implicated in poor prognosis corroborate the unfavorable role of HLA-G in tumor thyroid cells, inhibiting cytotoxic immune system cells and facilitating tumor evasion and progression. (AU)

• Processo FAPESP: 10/51649-9 - Expressão de HLA-G e polimorfismos das regiões promotora, codificadora e 3' não traduzida do respectivo gene em pacientes com carcinoma da glândula tireoide
• Beneficiário: Léa Maria Zanini Maciel
• Modalidade de apoio: Auxílio à Pesquisa - Regular