Project description:Primary uveal melanomas show multiple chromosomal aberrations. To identify genome variation in six human primary uveal melanomas, genome wide copy number variation (CNV) analyses were carried out in human primary uveal melanoma samples using array comparative genome hybridization.
Project description:Primary uveal melanomas show multiple genetic alterations. To determine mutational status of six human primary uveal melanomas, we performed whole exome sequencing (WES) and called Single Nucleotide Polimorphism (SNPs) to identify somatic mutations in these human primary uveal melanomas.
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.
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:Lack of specific markers for invasive uveal melanoma cells prevents early diagnosis of metastasis, while no systemic treatment options are available for patients with disseminated uveal melanomas. Intra-tumor heterogeneity has been recognized in numerous cancers as the main cause of metastasis development and therapy resistance. However, in uveal melanomas the specific subpopulations and their biological function which influence tumor behavior remained unknown. Here, using scRNA-seq analysis of six different primary uveal melanomas, we uncovered previously unrecognized intratumor heterogeneity. We localized diverse tumor-associated populations and transcriptional states in primary uveal melanomas. We also unraveled a gene regulatory network underlying a poor prognosis melanoma state. Heterogeneity was demonstrated in uveal melanoma tissue using the RNAscope assay. Thus, single-cell analysis offers an unprecedented view of intratumor heterogeneity in primary uveal melanoma, identified bona fide biomarkers for metastatic cells in the primary tumor, and unravel targetable modules driving metastase formation and growth, with critical implications for prognosis and therapeutic opportunity.