Circulating tumor cells mirror bone metastatic phenotype in prostate cancer

// Andreas Josefsson 1 , Karin Larsson 1 , Marianne Mansson 1 , Jens Bjorkman 3 , Eva Rohlova 3, 4, 5, 6 , Daniel Ahs 1 , Helena Brisby 2 , Jan-Erik Damber 1 and Karin Welen 1 1 Sahlgrenska Cancer Center, Department of Urology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden 2 Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden 3 TATAA Biocenter AB, Gothenburg, Sweden 4 Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic 5 Laboratory of Gene Expression, Institute of Biotechnology CAS, BIOCEV, Vestec, Czech Republic 6 Centre for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic Correspondence to: Karin Welen, email: karin.welen@gu.se Keywords: liquid biopsies; circulating tumor cells; skeletal metastases of prostate cancer Received: April 19, 2018     Accepted: May 17, 2018     Published: June 29, 2018 ABSTRACT Circulating tumor cells (CTCs) are promising biomarkers in prostate cancer (PC) because they derive from primary tumor and metastatic tissues. In this study, we used quantitative real-time PCR (qPCR) to compare the expression profiles of 41 PC-related genes between paired CTC and spinal column metastasis samples from 22 PC patients that underwent surgery for spinal cord compression. We observed good concordance between the gene expression profiles in the CTC and metastasis samples in most of the PC patients. Expression of nine genes ( AGR2 , AKR1C3 , AR , CDH1 , FOLH1 , HER2 , KRT19 , MDK , and SPINK1 ) showed a significant correlation between the CTC and metastasis samples. Hierarchical clustering analysis showed a similar grouping of PC patients based on the expression of these nine genes in both CTC and metastasis samples. Our findings demonstrate that CTCs mirror gene expression patterns in tissue metastasis samples from PC patients. Although low detection frequency of certain genes is a limitation in CTCs, our results indicate the potential for CTC phenotyping as a tool to improve individualized therapy in metastatic prostate cancer.