title: Potential role of nuclear PD-L1 expression in cell-surface vimentin positive circulating tumor cells as a prognostic marker in cancer patients.
abstract: Although circulating tumor cells (CTCs) have potential as diagnostic biomarkers for cancer, determining their prognostic role in cancer patients undergoing treatment is a challenge. We evaluated the prognostic value of programmed death-ligand 1 (PD-L1) expression in CTCs in colorectal and prostate cancer patients undergoing treatment. Peripheral blood samples were collected from 62 metastatic colorectal cancer patients and 30 metastatic prostate cancer patients. CTCs were isolated from the samples using magnetic separation with the cell-surface vimentin(CSV)-specific 84-1 monoclonal antibody that detects epithelial-mesenchymal transitioned (EMT) CTCs. CTCs were enumerated and analyzed for PD-L1 expression using confocal microscopy. PD-L1 expression was detectable in CTCs and was localized in the membrane and/or cytoplasm and nucleus. CTC detection alone was not associated with poor progression-free or overall survival in colorectal cancer or prostate cancer patients, but nuclear PD-L1 (nPD-L1) expression in these patients was significantly associated with short survival durations. These results demonstrated that nPD-L1 has potential as a clinically relevant prognostic biomarker for colorectal and prostate cancer. Our data thus suggested that use of CTC-based models of cancer for risk assessment can improve the standard cancer staging criteria and supported the incorporation of nPD-L1 expression detection in CTCs detection in such models.
authors.affiliation: Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Arun
authors.initials: A
authors.lastname: Satelli
authors.affiliation: Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Izhar Singh
authors.initials: IS
authors.lastname: Batth
authors.affiliation: Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Brownlee
authors.affiliation: Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Rojas
authors.affiliation: Department of Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Qing H
authors.initials: QH
authors.lastname: Meng
authors.affiliation: Departments of Surgical Oncology and Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Kopetz
authors.affiliation: Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.|The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, USA.
authors.forename: Shulin
authors.initials: S
authors.lastname: Li
mesh_terms: D060890:B7-H1 Antigen / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000097:blood / Q000175:diagnosis / Q000378:metabolism; D018572:Disease-Free Survival; D045325:HCT116 Cells; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis / Q000378:metabolism*; D009360:Neoplastic Cells, Circulating / Q000378:metabolism*; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis / Q000378:metabolism; D012189:Retrospective Studies; D014746:Vimentin / Q000378:metabolism*
chemical_list: D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor; C423236:CD274 protein, human; D014746:Vimentin