Frequent expression of PD-L1 on circulating breast cancer cells.
Mol Oncol
; 9(9): 1773-82, 2015 Nov.
Article
em En
| MEDLINE
| ID: mdl-26093818
ABSTRACT
Immune checkpoint regulators such as PD-L1 have become exciting new therapeutic targets leading to long lasting remissions in patients with advanced malignancies. However, in view of the remarkable costs and the toxicity profiles of these therapies, predictive biomarkers able to discriminate responders from non-responders are urgently needed. In the present paper, we provide evidence that PD-L1 is frequently expressed on metastatic cells circulating in the blood of hormone receptor-positive, HER2-negative breast cancer patients. We performed western blot, flow cytometry and immunocytochemical analyses to demonstrate the specificity of the PDL1 antibody used in our study and established immunoscores for PDL1 expression on single tumor cells. We then selected sixteen patients with circulating tumor cells (CTCs) using the CellSearch(®) system and found PD-L1((+)) CTCs in 11 patients (68.8%). The fraction of PD-L1((+)) CTCs varied from 0.2 to 100% in individual patients. This is the first report demonstrating the expression of PD-L1 on CTCs. The established CTC/PD-L1 assay can be used for liquid biopsy in future clinical trials for stratification and monitoring of cancer patients undergoing immune checkpoint blockade.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Mama
/
Neoplasias da Mama
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Antígeno B7-H1
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Células Neoplásicas Circulantes
Limite:
Aged
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Aged80
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Female
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Humans
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Middle aged
Idioma:
En
Revista:
Mol Oncol
Assunto da revista:
BIOLOGIA MOLECULAR
/
NEOPLASIAS
Ano de publicação:
2015
Tipo de documento:
Article