A multiplexed marker-based algorithm for diagnosis of carcinoma of unknown primary using circulating tumor cells

• Published in: Oncotarget 2016-01, Vol.7 (4), p.3662-3676
• Main Authors: Matthew, Elizabeth M, Zhou, Lanlan, Yang, Zhaohai, Dicker, David T, Holder, Sheldon L, Lim, Bora, Harouaka, Ramdane, Zheng, Si-Yang, Drabick, Joseph J, Lamparella, Nicholas E, Truica, Cristina I, El-Deiry, Wafik S
• Format: Article
• Language: English
• Subjects: Algorithms; Biomarkers, Tumor - metabolism; Breast Neoplasms - diagnosis; Breast Neoplasms - metabolism; Colorectal Neoplasms - diagnosis; Colorectal Neoplasms - metabolism; Female; Fluorescent Antibody Technique; Humans; Lung Neoplasms - diagnosis; Lung Neoplasms - metabolism; Male; Neoplasms, Unknown Primary - classification; Neoplasms, Unknown Primary - diagnosis; Neoplasms, Unknown Primary - metabolism; Neoplastic Cells, Circulating - pathology; Priority Research Paper; Prostatic Neoplasms - diagnosis; Prostatic Neoplasms - metabolism
• ISSN: 1949-2553; 1949-2553
• DOI: 10.18632/oncotarget.6657

Real-time, single-cell multiplex immunophenotyping of circulating tumor cells (CTCs) is hypothesized to inform diagnosis of tissue of origin in patients with carcinoma of unknown primary (CUP). In 20 to 50% of CUP patients, the primary site remains unidentified, presenting a challenge for clinicians in diagnosis and treatment. We developed a post-CellSearch CTC assay using multiplexed Q-dot or DyLight conjugated antibodies with the goal of detecting multiple markers in single cells within a CTC population. We adapted our approach to size-based CTC enrichment protocols for capturing CTCs and subsequent immunofluorescence (IF) using a minimal set of markers to predict the primary sites for common metastatic tumors. The carcinomas are characterized with cytokeratin 7 (CK7), cytokeratin 20 (CK20), thyroid transcription factor 1 (TTF-1), estrogen receptor (ER) or prostate-specific antigen (PSA. IF has been optimized in cultured tumor cells with individual antibodies, then with conjugated antibodies to form a multiplex antibody set. With IF, we evaluated antibodies specific to these 5 markers in lung, breast, colorectal, and prostate cancer cell lines and blood from metastatic prostate and breast cancer patients. This advanced technology provides a noninvasive, diagnostic blood test as an adjunct to routine tissue biopsy. Its further implementation requires prospective clinical testing.