Dados do Trabalho

Título

CANCER-ASSOCIATED CD90/THY-1 AS A USEFUL BIOMARKER IN THE BREAST CANCER MICROENVIRONMENT

Introdução

Breast cancer is a major public health problem. Several molecules have been proposed as cancer biomarkers, however, so far, only a few specific proteins are available to predict and detect breast cancer. In recent years, the mesenchymal stem cell marker CD90/THY-1 has been identified in several types of cancer. Our group demonstrated a relationship between CD90 and the basal-like human breast carcinoma subtype displaying a worse prognosis and lower survival rate.

Objetivo

The CD90 protein expression has been investigated through tissue microarray (TMA) in breast cancer stromal cells in human patient samples, aiming to understand its role in the stromal-epithelium interaction during malignant transformation and in the cellular heterogeneity typical of the breast tumor.

Métodos

Samples of primary breast tumors were obtained from the database of Hospital Beneficência Portuguesa de São Paulo, diagnosed with invasive breast carcinoma by biopsy, from January 2014 until December 2019. A retrospective analysis of the anatomopathological reports was carried out. Immunohistochemical staining was performed to analyze in-situ protein expression through tissue microarray (TMA). TMA was constructed using 5mm diameter cylindrical sections of paraffin blocks from biopsy samples of selected patients. We performed the E-cadherin, N-cadherin, and CD90 were analyzed using specific antibodies in both the tumor and in the intra-tumoral (stroma region Immunostaining was classified as “high” and “low” according to the score, which was multiplied by the intensity score.

Resultados

Analysis of the immunohistochemical indicates results. In the tumor region, we observed a predominance of CD90 low expression in the luminal A, Luminal B, triple-negative, and HER-2 subtypes, indicating a better prognosis. We observed an increase in CD90 expression in patients with Luminal B subtype, HER-2, and triple-negative in the stromal region (intratumoral). We demonstrated that high CD90 positivity can also be associated with increased metastatic potential and with a worse prognosis in the luminal B subtype for the first time while patients with high N-cadherin levels had CD90 higher expression. These results are correlated with the role of CD90 involved in epithelial-mesenchymal transition (EMT).

Conclusões

We identified CD90 as a potential malignancy marker in breast cancer. We observed that high CD90 positivity is associated with metastasis/low survival of basal and luminal B subtypes. CD90 is a promising molecule to identify a transformation and a new classification of molecular subtypes, when related to a worse prognosis, which contributes more precisely to the development of prognostic protocols and therapeutic strategies in patients with breast carcinoma.

Palavras-chave

biomarker; triple negative breast cancer;

Financiador do resumo

CAPES, CNPq, FAPESP

Área

Estudo Clínico - Tumores de Mama