Project description:Although remission rates for metastatic melanoma are generally very poor, some patients can survive for prolonged periods following metastasis. We used gene expression profiling, mitotic index (MI), and quantification of tumor infiltrating leukocytes (TILs) and CD3+ cells in metastatic lesions to search for a molecular basis for this observation and to develop improved methods for predicting patient survival. We identified a group of 266 genes associated with postrecurrence survival. Genes positively associated with survival were predominantly immune response related (e.g., ICOS, CD3d, ZAP70, TRAT1, TARP, GZMK, LCK, CD2, CXCL13, CCL19, CCR7, VCAM1) while genes negatively associated with survival were cell proliferation related (e.g., PDE4D, CDK2, GREF1, NUSAP1, SPC24). Identification of genes associated with survival of metastatic melanoma Survival Analysis was performed using Statistical Analysis of Microarrays B D denotes same patient with multiple reccurences
Project description:Although remission rates for metastatic melanoma are generally very poor, some patients can survive for prolonged periods following metastasis. We used gene expression profiling, mitotic index (MI), and quantification of tumor infiltrating leukocytes (TILs) and CD3+ cells in metastatic lesions to search for a molecular basis for this observation and to develop improved methods for predicting patient survival. We identified a group of 266 genes associated with postrecurrence survival. Genes positively associated with survival were predominantly immune response related (e.g., ICOS, CD3d, ZAP70, TRAT1, TARP, GZMK, LCK, CD2, CXCL13, CCL19, CCR7, VCAM1) while genes negatively associated with survival were cell proliferation related (e.g., PDE4D, CDK2, GREF1, NUSAP1, SPC24). Identification of genes associated with survival of metastatic melanoma
Project description:The current standard for investigating tumors is surgical biopsy, which is costly, invasive, and difficult to perform serially. As an adjunct, circulating tumor cells (CTCs)—cells that have broken away from the primary tumor or metastatic sites—can be obtained from a blood draw and offer the potential for obtaining serial genetic information and serving as biomarkers. Here, we detail the potential for melanoma CTCs to serve as biomarkers and discuss a clinically viable methodology for single-cell CTC isolation and analysis that overcomes previous limitations. We explore the use of melanoma CTC biomarkers by isolating and performing single-cell RNA sequencing on CTCs from melanoma patients. We then compared transcriptional profiles of single melanoma CTCs against A375 cells and peripheral blood mononuclear cells to identify unique genes differentially regulated in circulating melanoma tumor cells. The information that can be obtained via analysis of these CTCs has significant potential in disease tracking.
Project description:Purpose: Utility of immunological treatment in cancer has increased; however, many patients do not respond to treatment. Identification of robust predictive biomarkers is required to correctly stratify patients. Although clinical trials based on adoptive T cell therapy (ACT) have yielded high response rates and many durable responses in melanoma, 50-60% of the patients have no clinical benefit. Herein, we searched for predictive biomarkers to ACT in melanoma. Methods: Whole exome- and transcriptome sequencing, neoantigen prediction and immune cell signature analysis were applied to pre-treatment melanoma samples from 27 patients recruited to a clinical phase I/II trial of ACT in stage IV melanoma. All patients had previously been treated with other immunotherapies. Results: We found that clinical benefit was associated with significantly higher neoantigen load (P=0.025). High mutation and neoantigen load were significantly associated with improved progression-free and overall survival (P=8x10^-4 and P=0.001, respectively). Further, gene-expression analysis of pre-treatment biopsies showed that clinical benefit was associated with strong immune activation signatures including a high MHC-I antigen processing and presentation score. Conclusions: These results improve our understanding of clinical benefit of ACT in melanoma, which can lead to clinically useful predictive biomarkers to be used for selecting patients that benefit from these highly intensive treatment regimens.
Project description:The clinical success of immune-checkpoint inhibitors (ICI) in both resected and metastatic melanoma has confirmed the validity of therapeutic strategies that boost the immune system to counteract cancer. However, half of patients with metastatic disease treated with even the most aggressive regimen do not derive durable clinical benefit. Thus, there is a critical need for predictive biomarkers that can identify individuals who are unlikely to benefit with high accuracy, so that these patients may be spared the toxicity of treatment without the likely benefit of response. Ideally, such an assay would have a fast turnaround time and minimal invasiveness. Here, we utilize a novel platform that combines mass spectrometry with an artificial intelligence-based data processing engine to interrogate the blood glycoproteome in melanoma patients before receiving ICI therapy. We identify 143 biomarkers that demonstrate a difference in expression between the patients who died within six months of starting ICI treatment and those who remained progression-free for three years. We then develop a glycoproteomic classifier that predicts benefit of immunotherapy (HR=2.7; p=0.026) and achieves a significant separation of patients in an independent cohort (HR=5.6; p=0.027). To understand how circulating glycoproteins may affect efficacy of treatment, we analyze the differences in glycosylation structure and discover a fucosylation signature in patients with shorter overall survival (OS). We then develop a fucosylation-based model that effectively stratifies patients (HR=3.5; p=0.0066). Together, our data demonstrate the utility of plasma glycoproteomics for biomarker discovery and prediction of ICI benefit in patients with metastatic melanoma and suggest that protein fucosylation may be a determinant of anti-tumor immunity.
Project description:Analysis of DNA from fixed tissues specimens of 58 primary uveal melanomas, with known clinical outcome, to determine gene copy number variations that were associated with survival. Abstract: Uveal melanomas can be stratified into subgroups with high or low risk of metastatic death, according to the presence of gross chromosomal abnormalities. Where a monosomy 3 uveal melanoma is detected, patient survival at three years is reduced to 50%. However, approximately 5% of patients with a disomy 3 tumour ultimately develop metastasis, and a further 5% of monosomy 3 uveal melanoma patients’ exhibit disease-free survival for more than five years. Despite extensive knowledge of the chromosomal abnormalities occurring in uveal melanoma, the genes driving metastasis are not well defined. Gene copy number variations occurring in a well-characterised cohort of 58 formalin-fixed, paraffin-embedded uveal melanoma samples were identified using the Affymetrix SNP 6.0 whole genome microarray. Four genetic sub-groups of primary uveal melanoma were represented in the patient cohort: 1) disomy 3 with long-term survival; 2) metastasizing disomy 3; 3) metastasizing monosomy 3; and 4) monosomy 3 with long-term survival. Cox regression and Kaplan-Meier survival analysis identified three genes that were associated with differences in patient survival. Patients with an amplification of CNKSR3 (6q) or RIPK1 (6p) demonstrated longer survival than those with gene deletions or no copy number change (log rank, p=0.022 and p<0.001, respectively). Conversely, those patients with an amplification of PENK (8q) showed reduced survival (log rank p<0.001). CNKSR3, RIPK1 and PENK are novel candidate metastasis regulatory genes in uveal melanoma. This is the first report of amplification of a specific gene on 6p that is associated with improved uveal melanoma patient survival and suggests that the development of uveal melanomas with a propensity to metastasise may be limited by genes on 6p. 58 samples in total. Ten disomy 3 with long-term survival. Fifteen disomy 3 with metastasising. Seventeen monosomy 3 with long-term survival. Sixteen monosomy 3 metastasising.
Project description:In order to improve our understanding of microRNA (miRNA) deregulation in melanoma development and possible consequences for patient survival, miRNA expression profiles were determined, using an array based approach, in melanoma tumors, melanoma cell lines and normal melanocytes. Differentially expressed miRNAs were evaluated in relation to clinical characteristics, patient prognosis in terms of melanoma-specific survival, and mutational status for BRAF and NRAS. Agilent microarray platform containing 470 miRNAs was used to determine miRNA expression profiles in 3 normal melanocytes (as non-neoplastic control), 21 melanoma cell lines and 16 clinical samples from fresh frozen regional lymph node metastases. To validate the microarray platform, the expression levels of some miRNAs were evaluated using RT-PCR and the correlation between the two platforms was assessed using Pearson Correlation analysis. The results obtained were further verified and confirmed by RT-PCR in an independent set of melanoma samples. Association between deregulated miRNAs and survival was determined by Univariate Cox proportional hazards model and log rank test.
Project description:Acral melanoma, the most common melanoma subtype among non-Caucasian individuals, is associated with poor prognosis. However, its key molecular drivers remain obscure. Here, we perform integrative genomic and clinical profiling of acral melanomas from a cohort of 104 patients treated in North America or China. We find that recurrent, late-arising amplifications of cytoband chr22q11.21 are a leading determinant of inferior survival, strongly associated with metastasis, and linked to downregulation of immunomodulatory genes associated with response to immune checkpoint blockade. Unexpectedly, LZTR1 – a known tumor suppressor in other cancers – is a key candidate oncogene in this cytoband. Silencing of LZTR1 in melanoma cell lines caused apoptotic cell death independent of major hotspot mutations or melanoma subtypes. Conversely, overexpression of LZTR1 in normal human melanocytes initiated processes associated with metastasis, including anchorage-independent growth, formation of spheroids, and increased levels of MAPK and SRC activities. Our results provide insights into the etiology of acral melanoma and implicate LZTR1 as a key tumor promoter and therapeutic target.