Project description:Disseminated epithelial cells can be isolated from the bone marrow of a far greater frac-tion of prostate-cancer patients than the fraction of patients who progress to metastatic disease. To provide a better understanding of these cells, we have characterized their genomic altera-tions. We first present an array comparative genomic hybridization method capable of detecting genomic changes in the small number of disseminated cells (10-20) that can typically be ob-tained from bone-marrow aspirates of prostate-cancer patients. We show multiple regions of copy-number change, including alterations common in prostate cancer, such as 8p loss, 8q gain, and gain encompassing the androgen-receptor gene on Xq, in the disseminated cell pools from 11 metastatic patients. We found fewer and less striking genomic alterations in the 48 pools of disseminated cells from patients with organ-confined disease. However, we identify changes shared by these samples with their corresponding primary tumors and prostate-cancer altera-tions reported in the literature, evidence that these cells, like those in advanced disease, are disseminated tumor cells (DTCs). We also demonstrate that DTCs from patients with advanced and localized disease share several abnormalities, including losses containing cell-adhesion genes and alterations reported to associate with progressive disease. These shared alterations might confer the capability to disseminate or establish secondary disease. Overall, the spectrum of genomic deviations is evidence for metastatic capacity in advanced-disease DTCs and varia-tion in that capacity in DTCs from localized disease. Our analysis lays the foundation for eluci-dation of the relationship between DTC genomic alterations and progressive prostate cancer. Keywords: array comparative genomic hybridization, prostate cancer, disseminated cells
Project description:Background: Metastases result in 90% of all cancer deaths. Prostate cancer primary tumors evolve to become metastatic through selective alterations, such as amplification and deletion of genomic DNA. Methods: Genomic DNA copy number alterations were used to develop a gene signature that measured the metastatic potential of a prostate cancer primary tumor. We studied the genomic landscape of these alterations in 294 primary tumors and 49 metastases from 5 independent cohorts. Receiver-operating characteristic cross-validation and Kaplan-Meier survival analysis were performed to assess the accuracy of our predictive model. The signature was measured in a panel of 337 cancer cell lines from 29 different tissue origins. Results: We identified 399 copy number alterations around genes that were over-represented in metastases and predictive of whether a primary tumor will metastasize. Cross-validation analysis resulted in a predictive accuracy of 80.5% and log rank analysis of the metastatic potential score was significantly related to the endpoint of metastasis-free survival (p=0.014). The metastatic signature was observed in cell lines originating from lung, breast, colon, thyroid, rectum, pancreas and melanoma. The signature was comprised in part of genes of known or putative metastatic role — 8 solute carrier genes, 6 Cadherin family genes and 5 potassium channel genes — that function in metabolism, cell-to-cell adhesion and escape from anoikis/apoptosis. Conclusions: Somatic Copy number alterations are an independent predictor of metastatic potential. The data indicate a prognostic utility for using primary tumor genomics to assist in clinical decision making and developing therapeutics for prostate and likely other cancers. genomic DNA from 29 prostate cancer tumors with matched normals run on Affymetrix 6.0 SNP arrays.
Project description:Background: Metastases result in 90% of all cancer deaths. Prostate cancer primary tumors evolve to become metastatic through selective alterations, such as amplification and deletion of genomic DNA. Methods: Genomic DNA copy number alterations were used to develop a gene signature that measured the metastatic potential of a prostate cancer primary tumor. We studied the genomic landscape of these alterations in 294 primary tumors and 49 metastases from 5 independent cohorts. Receiver-operating characteristic cross-validation and Kaplan-Meier survival analysis were performed to assess the accuracy of our predictive model. The signature was measured in a panel of 337 cancer cell lines from 29 different tissue origins. Results: We identified 399 copy number alterations around genes that were over-represented in metastases and predictive of whether a primary tumor will metastasize. Cross-validation analysis resulted in a predictive accuracy of 80.5% and log rank analysis of the metastatic potential score was significantly related to the endpoint of metastasis-free survival (p=0.014). The metastatic signature was observed in cell lines originating from lung, breast, colon, thyroid, rectum, pancreas and melanoma. The signature was comprised in part of genes of known or putative metastatic role — 8 solute carrier genes, 6 Cadherin family genes and 5 potassium channel genes — that function in metabolism, cell-to-cell adhesion and escape from anoikis/apoptosis. Conclusions: Somatic Copy number alterations are an independent predictor of metastatic potential. The data indicate a prognostic utility for using primary tumor genomics to assist in clinical decision making and developing therapeutics for prostate and likely other cancers.
Project description:Prostate cancers exhibit a spectrum of molecular aberrations of which a substantial subset are amenable to targeted therapeutics. To determine the diversity of somatic alterations present in metastasis within and between individuals we characterized the genomic landscapes of 176 tumors acquired from 63 men. In contrast to the considerable variation across individuals, the molecular diversity of tumors within an individual was substantially less: alterations in putative drivers of cancer growth and cell cycle progression status were highly concordant. While androgen receptor activity was inversely related to proliferation, the expression of Fanconi Anemia complex genes was strongly associated with increased cell cycle progression. Inhibition of FANCA, FANCC, FANCD2 and BRCA2 expression reduced prostate cancer growth. The limited molecular diversity across metastases may result from bottlenecks imposed by the dissemination process, limited evolutionary time between metastatic seeding and tumor sampling, intermixing of tumor clones, and selection resulting from treatment pressures. Though exceptions exist, evaluating a single metastasis provides a reasonable assessment of the key molecular processes that occur throughout the spectrum of disseminated tumors within an individual, and may be used for selecting treatments based on predicted molecular vulnerabilities. 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.
Project description: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, and we compared the genomic diversity within and between individuals.
Project description:Metastasis to the brain is rare in prostate cancer and unfortunately, incredibly lethal. We evaluated the tissue biopsies of a patient with a treatment-induced metastatic lesion to the brain of the neuroendocrine prostate cancer (NEPC) subtype. We performed genomic, transcriptomic, and proteomic characterization on the primary prostate tumor, the metastatic brain NEPC, and an additional metastatic nodule in the dura with adenocarcinoma histology. These data are the proteomics result of this patient, with three replicates for each sample (primary prostate, dura adenocarcinoma, brain NEPC).
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:Comprehensive molecular cancer studies have extensively characterized most primary and some metastatic tumor types over the last decade. In prostate cancer, the most common tumor type in men, genomic studies have been most notably conducted for primary and metastatic tumors that had progressed under androgen deprivation therapies (ADT) to castration-resistant disease (CRPC). More recent studies have also looked at genetic alterations in a smaller number of prostate cancers frequently associated with neuroendocrine trans-differentiation. For this tumor type, it’s becoming clear that the complexity of genomic alterations does not allow an accurate assessment of the transformed phenotype. To overcome these hurdles, we show in patient-derived xenograft models how disease progression emerges at single-cell resolution and how pharmacologic perturbation can revert this process. Given this approach, we were able to investigate disease progression and androgen independence at single cell level: in our xenograft models, we show how tumor cell subpopulation progress along the trajectory from androgen-sensitive to insensitive disease.
Project description:Embryonic malignant transformation is concomitant to organogenesis, often affecting multipotent and migratory progenitors. Neuroblastoma (NB) is an emblematic example, arising from neural crest progenitors and characterized by a high heterogeneity and a widely disseminated clinical presentation. Metastatic triggers from the embryonic environment are suspected but yet unknown due to limited investigation access in patients and current models. Using combinations of ex vivo and in vivo models mimicking the embryonic context coupled to proteomic and transcriptomic analyses, we identify Olfactomedin1 (OLFM1) released by sympathetic derivatives at the core of a gene program promoting NB cells decohesion, primary tumor escape and dissemination. This OLFM signature discriminates metastatic from localized stages in NB patient cohorts. Finally, we report an extended tumor cell escape gene signature of disseminated forms specifically shared by cancers with neural-crest origin, revealing a sustained embryonic imprint of the lineage of origin, manifested in the metastatic properties of malignant cells.
Project description:Disseminated prostate cancer cells colonize the skeleton to progress into macroscopic lesions only if they successfully adapt to the bone microenvironment. We previously reported that the ability of prostate cancer cells to generate skeletal tumors in animal models correlated with the expression of the alpha-receptor for Platelet-Derived Growth Factor (PDGFRa). In this study we aimed to identify PDGFRa-regulated genes responsible for the acquisition of a bone-metastatic prostate phenotype. We performed genome-wide expression comparative analyses of human prostate cancer cell lines that differ for PDGFRa expression and propensity to establish tumors in the skeleton of animal models. We investigated the genes that were differentially regulated in the highly bone-metastatic PC3-ML cells and their low-metastatic counterpart PC3-N cells, and the genes differentially regulated between PC3-N and PC3-N with overexpression of PDGFRa (PC3NRa). We have previously shown that DU-145 cells lack PDGFRa and fail to survive longer than three days as disseminated tumor cells after homing to the mouse bone marrow. Interestingly, and in contrast to PC3-N cells, the exogenous expression of PDGFRa did not promote metastatic bone-tropism of DU-145 cells in our model. Thus, we examined the genes that were differentially regulated between DU-145 and DU-145(Ra) and excluded them from our candidate genes. Finally, to refine our findings and compensate for PC3 and DU-145 genetic disparity, we performed a comparative analysis of the genes differentially regulated between two bone metastatic single-cell progenies that were derived from PC3-ML cells. Seven human prostate cancer cell lines were analyzed in total for this study. Each cell line was analyzed in duplicate from two different passages in culture.