PD-L1 expression on circulating tumor cells and platelets in patients with metastatic breast cancer.

ABSTRACT:

Background

Immune checkpoint inhibition is effective in several cancers. Expression of programmed death-ligand 1 (PD-L1) on circulating tumor or immune effector cells could provide insights into selection of patients for immune checkpoint inhibition.

Methods

Whole blood was collected at serial timepoints from metastatic breast cancer patients and healthy donors for circulating tumor cell (CTC) and platelet PD-L1 analysis with a phycoerythrin-labeled anti-human PD-L1 monoclonal antibody (Biolegend clone 29E.2A3) using the CellSearch® assay. CTC PD-L1 was considered positive if detected on at least 1% of the cells; platelet PD-L1 was considered positive if ≥100 platelets per CellSearch frame expressed PD-L1.

Results

A total of 207 specimens from 124 metastatic breast ca

SUBMITTER: Darga EP 

PROVIDER: S-EPMC8592410 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature