Project description:Prostate cancer (PCa) disseminated tumor cells (DTC) in the bone marrow (BM) can remain dormant for prolonged periods before recurrence. Our aim was to characterize individual prostate DTC, analyze tumor cell heterogeneity, and identify markers of tumor dormancy. Custom Agilent 44K whole human genome expression oligonucleotide microarrays were used to profile single disseminated tumor cells isolated from bone marrow (BM) samples of four patients with no evidence of disease (NED) upon follow-up and six advanced disease (ADV) prostate cancer patients. Essentially, a two-step selection process was employed, in which anti-CD45 and anti-CD61 conjugated to immunomagnetic beads were used for negative selection, and anti-HEA was used for positive selection. Cells were then fluorescently stained for BerEP4, counter stained with RPE anti-CD45, and individually selected (10 single cells each per patient) under fluorescent light using a micropipette system for further analysis. RNA was amplified using the WT-Oviation one-direct system and hybridized against a common reference pool of prostate tumor cell lines.
Project description:Prostate cancer (PCa) disseminated tumor cells (DTC) in the bone marrow (BM) can remain dormant for prolonged periods before recurrence. Our aim was to characterize individual prostate DTC, analyze tumor cell heterogeneity, and identify markers of tumor dormancy.
Project description:Prostate cancer (PCa) cells, when disseminated to the bone, may stay quiescent or dormant for years before proliferation into overt metastases. Previous studies suggest that osteoblasts, the bone forming cells, may be responsible for induction of dormancy of bone-disseminated prostate cancer cells.
Project description:Understanding dormancy in prostate cancer (PCa) is challenging due to model availability. Here, using murine and human PCa cell lines, we generated a stress-induced model of dormancy in vitro and demonstrated that the phenotype could be sustained upon intrailiac artery delivery into the bone marrow microenvironment. RNA-Seq analysis revealed that the transcription factor PR domain containing 16 (PRDM16) was commonly upregulated in dormant PCa cells compared to controls. Further, bone marrow disseminated tumor PCa cells from primary orthotopic tumors were largely positive for PRDM16. Genetic ablation and forced ectopic expression supported a role for PRDM16 in maintaining PCa dormancy in vitro and in vivo. Clinically, PRDM16 negatively correlated with disease recurrence, and PRDM16 negatively correlated with the E2F cell cycle program in disseminated tumor cells derived from PCa patient bone marrow. Gene enrichment and characterization studies implicated PRDM16 as a regulator of metabolic and cell cycle pathways. ChIP-qPCR further revealed that PRDM16 binds upstream of the promoter of RB1, a potent repressor of E2F activity. Overall, this study developed a straightforward method for inducing cancer cell dormancy and applied this approach to find that PRDM16 governs an intrinsic dormancy program in PCa.
Project description:Intraindividual tumor heterogeneity may reduce the efficacy of molecularly guided systemic therapy for cancers that have metastasized. To determine whether the genomic alterations in a single metastasis provide a reasonable assessment of the major oncogenic drivers of other dispersed metastases in an individual, we analyzed multiple tumors from men with disseminated prostate cancer through whole-exome sequencing, array comparative genomic hybridization (CGH) and RNA transcript profiling [GSE74685], and we compared the genomic diversity within and between individuals. Custom Agilent 44K whole human genome expression oligonucleotide microarrays were used to profile 171 CRPC tumors from 63 patients. RNA was amplified prior to hybridization against a common reference pool of prostate tumor cell lines. Custom Agilent 415K whole human CGH microarrays were used to profile 149 CRPC tumors from 60 patients. Genomic DNA from tumors was hybridized against a pool of reference normal male DNA.