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:Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, following initial treatment, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing three apparently dormant patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering on immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells resumed cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide evidence to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells escape from dormancy. Targeting TGF-beta 2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis. Custom Agilent-016162 44K whole human genome expression oligonucleotide microarrays were used to profile dormant and proliferating cells isolated from three separate LuCaP xenograft lines grown in co-culture with bone marrow stromal cells isolated from a patient with PCa bone metastases. RNA from 10 cells was amplified prior to hybridization against a common reference pool of prostate tumor cell lines.
Project description:Dormancy of disseminated tumor cells in secondary organs leads to late breast cancer-related deaths after relapse. The bone marrow is one of the primary breast cancer metastatic sites and is associated with poor prognosis. Here, we investigated the role of major factors of the bone marrow, BMP4 and TGF?2, in regulating cancer cell dormancy. Unexpectedly, we observed that TGF?2 and BMP4 have a synergistic effect that induces dormancy in both normal and transformed mammary stem cells. Several assays (3D matrigel, FUCCI Cell Cycle Indicator) showed that co-exposure to TGF?2 and BMP4 had a stronger anti-proliferative effect than each ligand alone. In addition, transformed cells fully retained this synergistic effect while they became less sensitive to individual cytokines. Surprisingly, single-cell RNAseq analysis revealed the heterogeneity of the G0 compartment at the transcriptomic level. We identified a unique deep dormant cluster under TGF?2 and BMP4 co-exposure characterized by a blended signature from treatments by TGF?2 or BMP4 alone. These findings reveal that disseminated breast cancer cells in the bone marrow are placed in a deep dormant stage by the synergistic effect of TGF?2 and BMP4 that neither factor can achieve alone. Lastly, our data suggest that the local BMP4 levels decrease with tissue aging and can therefore contribute to dormant cell awakening. By providing a better understanding of BMP4/TGF?2 signaling, our results open opportunities to prevent cancer relapse.
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.
Project description:Dissemination of cancer stem cells (CSCs) serves as the basis of metastasis. Recently, we demonstrated that circulating prostate cancer (PCa) targets the hematopoietic stem cell (HSCs) ‘niche’ in marrow during dissemination. Once in the niche, disseminated tumor cells (DTCs) may remain dormant for extended periods. As the major function of the HSC niche is to maintain stem cell functions, we hypothesized that the niche regulates CSC activities of DTCs. We show that DTCs recovered from marrow were significantly enriched for a CSC phenotype. Critically, the conversion of DTCs to CSCs is regulated by niche. The data demonstrate that the niche plays a significant role in maintaining tumor-initiating PCa in marrow and suggests a functional relationship between CSCs and dormancy. Understanding how the marrow niche regulates the conversion of DTCs to CSCs is critical for the development of therapeutics specifically targeting skeletal bone metastasis and dormancy. We used microarrays to determine the global changes in gene expression underlying the significant roles of the marrow niche in activating cancer stem-like cell programs of prostate caner.
Project description:The ability to interrogate circulating tumor cells (CTC) and disseminated tumor cells (DTC) is restricted by the small number detected and isolated (typically <10). We wanted to determine if a commercially available technology could provide a transcriptomic profile of a single prostate cancer (PCa) cell. We clonally selected and cultured a single passage of cell cycle synchronized C4-2B PCa cells. Ten sets of single, 5-, or 10-cells were isolated using a micromanipulator under direct visualization with an inverted microscope. Additionally, we analyzed 10 individual DTC isolated from each of 2 patients with metastatic PCa. We have shown that a transcriptomic profile can be obtained from a single cell using commercially available technology. As expected, fewer amplified genes are detected from a single-cell sample than from pooled cell samples, but this method can be used to obtain a transcriptomic profile from DTC isolated from the bone marrow of patients with PCa. Custom Agilent 44K whole human genome expression oligonucleotide microarrays were used to profile clonally selected and cultured single passage of cell cycle synchronized C4-2B PCa cells isolated using a micromanipulator under direct visualization with an inverted microscope into ten sets of single, 5-, or 10-cells. Single disseminated tumor cells were isolated from bone marrow (BM) samples of two advanced 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 hybridization against a common reference pool of prostate tumor cell lines. Data from C42B cell data and data from single cells isolated from the bone marrow of patients were normalized and analyzed separately.
Project description:Cancer cells can disseminate from early-evolved primary lesions. It is thought that a state of early disseminated cancer cell (early DCC) dormancy would precede genetic maturation of DCCs and metastasis initiation. Here we reveal at single cell resolution a previously unrecognized role of mesenchymal- and pluripotency-like programs in coordinating early cancer cell spread and a long-lived dormancy program in early DCCs. We identify in early lesions and early DCCs, the transcription factor ZFP281 as an inducer of mesenchymal- and primed pluripotency-like programs, which is absent in advanced primary tumors and overt metastasis. ZFP281 not only controls the early spread of cancer cells but also locks early DCCs in a prolonged dormancy state by preventing the acquisition of an epithelial-like proliferative program. Thus, ZFP281-driven dormancy of early DCCs may be a rate-limiting step in metastatic progression functioning as a first barrier that DCCs must overcome to then undergo genetic maturation. This data set aims to characterize MMTV-Neu early and late lung disseminated cancer cells (DCCs).