Whole-genome expression analysis of melanoma tumor biopsies from a population-based cohort.
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE65904 | GEO | 2015/04/01
SECONDARY ACCESSION(S): PRJNA275358
REPOSITORIES: GEO
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Project description:Analysis of gene expression profiles in metastatic melanoma to validate prognostic signatures. Total RNA was extracted from fresh-frozen melanoma tumors and genome-wide expression profiling was performed using Illlumina Human HT-12V4.0 BeadChip arrays by standard methods. After removal of replicate samples there were 214 unique melanoma samples left.
2015-04-01 | E-GEOD-65904 | biostudies-arrayexpress
Project description:Analysis of gene expression profiles in metastatic melanoma to validate prognostic signatures. Total RNA was extracted from fresh-frozen melanoma tumors and genome-wide expression profiling was performed using Illlumina Human HT-12V4.0 BeadChip arrays by standard methods. After removal of replicate samples there were 214 unique melanoma samples left.
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Project description:Circulating tumor cells (CTCs) are critical in the development of distant organ tumor metastasis, and are associated with advanced cancer stage and poor patient outcome. Here, we present the first genome-wide nucleotide-level characterization of CTCs. Our single-nucleotide polymorphism (SNP) analysis in patients with melanoma involved: 1) global comparative genomic analysis of CTCs and matched regional metastases, 2) identification of key genomic aberrations in CTCs, 3) verification of these target genes in aggressive distant tumor metastases, and 4) evidence of selective expression and functional consequence of CTC-associated genes in melanomas. We report 131 aberrant loci in CTCs that are potentially pro-metastatic, and show that such expression of a 5-marker gene panel (CSMD2, CNTNAP5, FLJ14051, ADAM6, TRPM2) in melanomas confers prognostic utility. Successful treatment of melanoma requires understanding of the metastatic process and identification of patients with tumors most likely to develop aggressive metastatic disease. Melanomas are heterogeneous, and CTCs have long been recognized as vehicles for cancer spread, representing particularly aggressive tumor clones that can evolve into successful clinical metastases. Elucidation of genomic aberrations in CTCs will aid in the development of prognostic biomarkers and therapeutic strategies to target CTCs to prevent or control distant cancer spread. This study provides the first detailed genomic confirmation of the close relation between CTCs and tumor metastases, and illustrates how CTCs can be utilized as a novel approach and rational source for identification of pro-metastatic genes in cancer research. Three individual patient cohorts were utilized in the study. CNV and LOH loci were evaluated initially in metastatic melanoma patients (n=13) in a discovery cohort. SNP loci that harbored CNV/LOH in CTCs were then separately verified for: (a) presence in distant organ metastasis (AJCC Stage IV melanoma) (n=27), and (b) relevance to prognosis in regional melanoma metastasis (AJCC Stage III melanoma) (n=35). The first discovery patient cohort group was utilized for capture of CTCs, and consisted of peripheral blood mononuclear cell (PBMC) and tumor specimens from metastatic melanoma patients (n=13). CTC-related loci were verified in a second cohort of patients with Stage IV distant organ metastases (n=27), including 15 brain, 4 lung, and 8 gastrointestinal (bowel, liver) metastases. The third patient cohort consisted of early passage (<12) established melanoma cell lines derived from 35 regional melanoma metastases (Stage III) for evaluation of the prognostic utility of the CTC-associated aberrant loci.
2014-07-01 | E-GEOD-43934 | biostudies-arrayexpress
Project description:We performed global microRNA expression profiling of a cohort of primary melanoma patient samples linked to a well-annotated clinical database. The goal of this study was to identify microRNA that are associated to or correlated with various clinical parameters and patient outcomes. Candidate microRNA were identified for building prognostic models and functional testing. 119 primary melanoma samples were analyzed in two color arrays. The reference sample used was an equal combination of all samples analyzed. By this design, ratio data of test sample/reference is mean-centered data.
2015-02-01 | E-GEOD-62371 | biostudies-arrayexpress
Project description:We performed global microRNA expression profiling of a cohort of primary melanoma patient samples linked to a well-annotated clinical database. The goal of this study was to identify microRNA that are associated to or correlated with various clinical parameters and patient outcomes. Candidate microRNA were identified for building prognostic models and functional testing. 92 primary melanoma (well-annotated with long clinical follow-up) and 9 congenital nevi samples were analyzed to Exiqon miRCURY two color arrays. The reference sample used was an equal combination of all samples analyzed. By this design, ratio data of test sample/reference is mean-centered data.
2015-02-01 | E-GEOD-62370 | biostudies-arrayexpress
Project description:Background: Timely diagnosis is important for successful treatment of cutaneous melanoma. Currently, Breslow tumor thickness and mitotic rate are used for malignant melanoma classification and prognosis, but these parameters can assess disease progression risk only to a certain degree. Therefore, there is a need for new melanoma protein biomarkers that would aid early and accurate diagnosis and prediction of their metastatic potential. Methodology and Findings: This retrospective case control study is based on proteomic profiling of formalin-fixed archival tissues of 31 early-stage head and neck cutaneous malignant melanoma samples using liquid chromatography / mass spectrometry. A melanoma proteomic profile was identified and protein expression levels were compared to the proteome profile of melanocytic naevi and correlated to established prognostic factors and disease-specific survival. In accordance with the American Joint Committee on Cancer guidelines, recursive partitioning multivariate analysis was used to identify potential biomarkers associated with metastatic potential of early-melanoma. Heterogeneous nuclear ribonucleoprotein M and heat shock protein 90 alpha were profiled as independent prognostic factors. Their elevated expression was clinically relevant for predicting an exceedingly high metastatic hazard ratio. These proteins were superior in estimating disease progression risk when compared to Breslow thickness and mitotic rate. Conclusions and Significance: Identification of biomarkers in early stage cutaneous head and neck melanoma is an important step towards predicting metastatic potential and prognosis of the disease. Clinical confirmation and further validation of the proteins identified in this study would provide a novel tool for identifying patients at risk for developing metastatic disease.
2019-11-27 | PXD015137 | Pride
Project description:We performed global microRNA expression profiling of a cohort of primary melanoma patient samples linked to a well-annotated clinical database. The goal of this study was to identify microRNA that are associated to or correlated with various clinical parameters and patient outcomes. Candidate microRNA were identified for building prognostic models and functional testing.
2015-02-01 | GSE62370 | GEO
Project description:We performed global microRNA expression profiling of a cohort of primary melanoma patient samples linked to a well-annotated clinical database. The goal of this study was to identify microRNA that are associated to or correlated with various clinical parameters and patient outcomes. Candidate microRNA were identified for building prognostic models and functional testing.
2015-02-01 | GSE62371 | GEO
Project description:The identification of novel tumor-specific markers may improve understanding of melanoma progression and prognostic accuracy. Whole genome expression profiling of 46 primary melanomas, 12 metastases, and 16 normal skin samples using Affymetrix U133 PLUS 2.0 array generated gene lists including both known and new melanoma genes. The molecular genetic alterations contributing to the pathogenesis of melanoma are incompletely defined and few independent prognostic features have been identified beyond the pathologic characteristics of the primary tumor. Early stage melanoma is frequently curable, in contrast to the inferior prognosis of melanomas with regional lymph nodes involvement and the incurability of distant metastatic disease. The identification of novel tumor-specific markers may improve our understanding of melanoma progression and prognostic accuracy. To find differentially expressed genes that can distinguish melanoma from normal tissue, we performed a whole genome expression profiling of 46 primary melanoma samples, 12 regional or distant metastases, and 16 normal skin samples using Affymetrix U133 2.0 Plus array. Our study generated lists of differentially expressed genes in melanoma and identified novel prognostic marker HMGA2. It is a novel, highly overexpressed melanoma gene associated with poor prognosis. The overexpression of HMGA2 is strongly associated with regional and distant metastases and serves as an independent predictor of disease-free survival and overall survival in melanoma. Melanoma samples were obtained through an IRB-approved protocol using informed consent at the University of Michigan Multidisciplinary Melanoma Clinic. A portion of pigmented lesions clinically suspicious for melanoma and known melanoma were sampled by punch biopsy at the time of excision. The punch biopsy was bisected; half was sent to for clinical diagnosis and the other half along with adjacent normal skin when available immediately snap-frozen in liquid nitrogen. Snap-frozen tissue was embedded in OCT (TissueTek) followed by frozen sectioning and H&E slide preparation. The slides were evaluated by dermatopathologist who identified areas with greater than 70% tumor cellularity, which were sampled for RNA extraction. Primary melanomas and melanoma metastases were derived from different patients. Metastatic samples included lymph nodes (n=8), subcutaneous soft tissue (n=2), spleen (n=1), and small intestine (n=1).
2012-06-07 | E-GEOD-15605 | biostudies-arrayexpress
Project description:Melanoma remains the most lethal skin cancer, mainly because of high resistance to therapy. Side population (SP) cells are found in many types of cancer and are usually enriched in therapy-resistant as well as tumorigenic cells. Here, we identified a Hoechst dye-effluxing SP in a large series of human melanoma samples representing different progression phases. The SP size did not change with disease stage but was correlated with the prognostic “Breslow’s depth” in the primary (cutaneous) tumors. When injected into immunodeficient mice, the SP generated larger tumors than the bulk “main population” (MP) melanoma cells in two consecutive generations, and showed tumorigenic capacity at lower cell numbers than the MP. In addition, the SP reconstituted the heterogeneous composition of the human A375 melanoma cell line, and its clonogenic activity was 2.5-fold higher than that of the MP. Gene-expression analysis revealed upregulated expression in the melanoma SP (versus the MP) of genes associated with chemoresistance and anti-apoptosis. Consistent with these molecular characteristics, the SP increased in proportion when A375 cells were exposed to the melanoma standard chemotherapeutic agent dacarbazine, and to the aggravating condition of hypoxia. In addition, the SP showed enhanced expression of genes related to cell invasion and migration, as well as to putative (melanoma) cancer stem cells (CSC) including ABCB1 and JARID1B. ABCB1 immunoreactivity was detected in a number of tumor cells in human melanomas, and in particular in clusters at the invasive front of the primary tumors. Together, our findings support that the human melanoma SP is enriched in tumorigenic and chemoresistant capacity, considered key characteristics of CSC. The melanoma SP may therefore represent an interesting therapeutic target. Four primary melanomas (subtype SSMM) were dissociated into single cells. From each of these single cell suspensions, side population (SP) and bulk \main population\ (MP) cells were isolated based on their Hoechst-effluxing capability using fluorescence-activated cell sorting. Gene expression of SP cells is analyzed relative to the gene expression of the corresponding MP cells.
2014-05-27 | E-GEOD-48838 | biostudies-arrayexpress