Dados do Resumo

Título

CD90/THY-1 as a Valuable Biomarker in the Breast Cancer Microenvironment

Introdução

Breast cancer represents a significant public health challenge. While numerous molecules have been proposed as potential biomarkers, only a few specific proteins are currently validated for predicting and diagnosing breast cancer. The mesenchymal stem cell marker CD90/THY-1 has recently been associated with various malignancies. Recently, our research group identified a correlation between CD90 expression and the basal-like subtype of human breast carcinoma, which is linked to a poor prognosis and decreased survival rates.

Objetivo

This study aims to evaluate CD90 protein expression in breast cancer stromal cells using tissue microarray (TMA) from patient-derived samples. The objective is to investigate its involvement in stromal-epithelial interactions during malignant transformation and its contribution to the cellular heterogeneity of breast tumors.

Métodos

Primary breast tumor samples were collected from the Hospital Beneficência Portuguesa database, involving patients diagnosed with invasive breast carcinoma between January 2014 and December 2019. A retrospective analysis of pathology reports was conducted. Immunohistochemical analysis was performed to assess protein expression via TMA, constructed using 5 mm cylindrical cores from paraffin-embedded biopsy samples. E-cadherin, N-cadherin, and CD90 expression levels were evaluated in both tumor and intra-tumoral stromal regions. Immunostaining was classified as 'high' or 'low' based on a composite score obtained by multiplying staining extent and intensity.

Resultados

Immunohistochemical analysis revealed that low CD90 expression was predominant in the tumor regions of luminal A, luminal B, triple-negative, and HER-2 subtypes, indicating a better prognosis. Conversely, increased CD90 expression was observed in the stromal (intratumoral) regions of patients with luminal B, HER-2, and triple-negative subtypes. Notably, for the first time, we demonstrated that high CD90 expression was associated with greater metastatic potential and worse prognosis, particularly in the luminal B subtype. Lower CD90 expression correlated with E-cadherin, whereas higher CD90 expression was linked to in reased N-cadherin levels, supporting CD90’s role in the epithelial-mesenchymal transition (EMT).

Conclusões

CD90 was identified as a potential biomarker of malignancy in breast cancer. High CD90 expression was associated with increased metastasis and reduced survival, particularly in basal-like and luminal B subtypes. CD90 represents a promising target for further exploration in identifying malignant transformation and refining molecular subtype classifications linked to poor prognosis, which may enhance prognostic accuracy and inform therapeutic strategies for breast cancer patients.

Financiador do resumo

CAPES, CNPq, FAPESP

Palavras Chave

biomarker; triple negative breast cancer; PROGNOSTIC