title: Combined genome and transcriptome analysis of single disseminated cancer cells from bone marrow of prostate cancer patients reveals unexpected transcriptomes.
abstract: Bone is the most frequent site of metastasis in prostate cancer and patients with bone metastases are deemed incurable. Targeting prostate cancer cells that disseminated to the bone marrow before surgery and before metastatic outgrowth may therefore prevent lethal metastasis. This prompted us to directly analyze the transcriptome of disseminated cancer cells (DCC) isolated from patients with nonmetastatic (UICC stage M0) prostate cancer. We screened 105 bone marrow samples of patients with M0-stage prostate cancer and 18 bone marrow samples of patients without malignancy for the presence of EpCAM(+) single cells. In total, we isolated 270 cells from both groups by micromanipulation and globally amplified their mRNA. We used targeted transcriptional profiling to unambiguously identify DCCs for subsequent in-depth analysis. Transcriptomes of all cells were examined for the expression of EPCAM, KRT8, KRT18, KRT19, KRT14, KRT6a, KRT5, KLK3 (PSA), MAGEA2, MAGEA4, PTPRC (CD45), CD33, CD34, CD19, GYPC, SCL4A1 (band 3), and HBA2. Using these transcripts, we found it impossible to reliably identify true DCCs. We then applied combined genome and transcriptome analysis of single cells and found that EpCAM(+) cells from controls expressed transcripts thought to be epithelial-specific, whereas true DCCs may express hematopoietic transcripts. These results point to an unexpected transcriptome plasticity of epithelial cancer cells in bone marrow and question common transcriptional criteria to identify DCCs.
authors.affiliation: Chair of Experimental Medicine and Therapy Research, University of Regensburg, Regensburg, Germany.
authors.forename: Miodrag
authors.initials: M
authors.lastname: Gužvić
authors.affiliation: Chair of Experimental Medicine and Therapy Research, University of Regensburg, Regensburg, Germany. Department of Oncology, Hospital Barmherzige Brüder, Regensburg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Braun
authors.affiliation: Department of Urology, Caritas-Hospital St. Josef, University of Regensburg, Regensburg, Germany.
authors.forename: Roman
authors.initials: R
authors.lastname: Ganzer
authors.affiliation: Department of Urology, Caritas-Hospital St. Josef, University of Regensburg, Regensburg, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Burger
authors.affiliation: Department of Trauma Surgery, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Nerlich
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Bad Abbach, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Winkler
authors.affiliation: Department of Immunology, University of Regensburg, Regensburg, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Werner-Klein
authors.affiliation: Project Group Personalized Tumour Therapy, Fraunhofer Institute of Experimental Medicine and Toxicology, Regensburg, Germany.
authors.forename: Zbigniew T
authors.initials: ZT
authors.lastname: Czyż
authors.affiliation: Project Group Personalized Tumour Therapy, Fraunhofer Institute of Experimental Medicine and Toxicology, Regensburg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Polzer
authors.affiliation: Chair of Experimental Medicine and Therapy Research, University of Regensburg, Regensburg, Germany. Project Group Personalized Tumour Therapy, Fraunhofer Institute of Experimental Medicine and Toxicology, Regensburg, Germany. christoph.klein@ukr.de.
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Klein
mesh_terms: D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000235:genetics; D001853:Bone Marrow / Q000378:metabolism* / Q000473:pathology; D001859:Bone Neoplasms / Q000235:genetics / Q000473:pathology / Q000556:secondary; D015815:Cell Adhesion Molecules / Q000235:genetics; D000071858:Epithelial Cell Adhesion Molecule; D015894:Genome, Human; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology; D012333:RNA, Messenger / Q000096:biosynthesis; D059467:Transcriptome / Q000235:genetics*
chemical_list: D000951:Antigens, Neoplasm; D015815:Cell Adhesion Molecules; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; D009363:Neoplasm Proteins; D012333:RNA, Messenger