Distinct Sets of Genetic Alterations in Melanoma
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE2631 | GEO | 2005/11/05
SECONDARY ACCESSION(S): PRJNA92269
REPOSITORIES: GEO
Similar Datasets
Project description:We compared genome-wide DNA copy number alterations and mutational status in BRAF and RAS genes of 126 primary melanomas arising in four groups in which UV exposure differ: skin with (n=30), and without chronic sun damage (n=40); palms, soles and subungual (acral) sites (n=36) (which have very little sun exposure); and mucosa (n=20) (no sun exposure).
2010-06-09 | E-GEOD-2631 | biostudies-arrayexpress
Project description:Melanomas on mucosal membranes, acral skin (soles, palms, and nail bed), and skin with chronic sun-induced damage have infrequent mutations in BRAF and NRAS, genes within the mitogenactivated protein (MAP) kinase pathway commonly mutated in melanomas on intermittently sun-exposed skin. This raises the question of whether other aberrations are occurring in the MAP kinase cascade in the melanoma types with infrequent mutations of BRAF and NRAS. Oncogenic mutations in KIT were found in three of seven tumors with amplifications. Examination of all 102 primary melanomas found mutations and/or copy number increases of KIT in 39% ofmucosal, 36% of acral, and 28% of melanomas on chronically sun-damaged skin, but not in any (0%) melanomas on skin without chronic sun damage. Seventy-nine percent of tumors with mutations and 53% of tumors with multiple copies of KIT demonstrated increased KIT protein levels. KIT is an important oncogene in melanoma. Because the majority of the KIT mutations we found in melanoma also occur in imatinib-responsive cancers of other types, imatinib may offer an immediate therapeutic benefit for a significant proportion of the global melanoma burden. Keywords: melanoma, oncogene, comparative genomic hybridization, KIT
2006-09-09 | GSE4747 | GEO
Project description:Oncogenic alterations to DNA are not transforming in all cellular contexts. This may be due to pre-existing transcriptional programs in the cell of origin. Here, we define anatomic position as a major determinant of why cells respond to specific oncogenes. Cutaneous melanoma arises throughout the body, whereas the acral subtype arises on the palms of the hands, soles of the feet, or under the nails. We sequenced the DNA of cutaneous and acral melanomas from a large cohort of human patients and found a specific enrichment for BRAF mutations in cutaneous melanoma but CRKL amplifications in acral melanoma. We modeled these changes in transgenic zebrafish models and found that CRKL-driven tumors predominantly formed in the fins of the fish. The fins are the evolutionary precursors to tetrapod limbs, indicating that melanocytes in these acral locations may be uniquely susceptible to CRKL. RNA profiling of these fin/limb melanocytes, compared to body melanocytes, revealed a positional identity gene program typified by posterior HOX13 genes. This positional gene program synergized with CRKL to drive tumors at acral sites. Abrogation of this CRKL-driven program eliminated the anatomic specificity of acral melanoma. These data suggest that the anatomic position of the cell of origin endows it with a unique transcriptional state that makes it susceptible to only certain oncogenic insults.
2022-01-12 | PXD027968 | Pride
Project description:Acral melanoma is a rare subtype of melanoma that arises on the non-hair-bearing skin of the palms, soles and nail beds. In this study, we used single cell RNA-seq (scRNA-seq) to map the transcriptional landscape of acral melanoma and identify novel immunotherapeutic targets.
2022-02-14 | GSE189889 | GEO
Project description:Oncogenic alterations to DNA are not transforming in all cellular contexts. This may be due to pre-existing transcriptional programs in the cell of origin. Here, we define anatomic position as a major determinant of why cells respond to specific oncogenes. Cutaneous melanoma arises throughout the body, whereas the acral subtype arises on the palms of the hands, soles of the feet, or under the nails3. We sequenced the DNA of cutaneous and acral melanomas from a large cohort of human patients and found a specific enrichment for BRAF mutations in cutaneous melanoma but CRKL amplifications in acral melanoma. We modeled these changes in transgenic zebrafish models and found that CRKL-driven tumors predominantly formed in the fins of the fish. The fins are the evolutionary precursors to tetrapod limbs, indicating that melanocytes in these acral locations may be uniquely susceptible to CRKL. RNA profiling of these fin/limb melanocytes, compared to body melanocytes, revealed a positional identity gene program typified by posterior HOX13 genes. This positional gene program synergized with CRKL to drive tumors at acral sites. Abrogation of this CRKL-driven program eliminated the anatomic specificity of acral melanoma. These data suggest that the anatomic position of the cell of origin endows it with a unique transcriptional state that makes it susceptible to only certain oncogenic insults.
2022-01-17 | GSE181748 | GEO
Project description:We investigated copy number alterations in melanomas from two cohorts of Braf mutant mice (UV exposed and no UV exposure) by comparing tumour DNA to germline DNA by array CGH There were 15 tumour samples in each cohort (UV exposed and no UV exposure)
2014-06-11 | E-GEOD-58265 | biostudies-arrayexpress
Project description:We investigated copy number alterations in melanomas from two cohorts of Braf mutant mice (UV exposed and no UV exposure) by comparing tumour DNA to germline DNA by array CGH
2014-06-11 | GSE58265 | GEO
Project description:Ultraviolet radiation (UV) is causally linked to cutaneous melanoma, yet the underlying epigenetic mechanisms, known as molecular sensors of exposure, have never been characterized in clinical biospecimen. DNA methylome, genome and transcriptome analyses of cutaneous melanoma in two cohorts identified UV-related alterations in regulatory regions and immunological pathways and revealed novel cancer driver genes affecting patient survival. TAPBP, the top gene and a member of the immunoglobulin superfamily, encompassed several CpG methylation sites altered by UV and independently validated by bisulfite pyrosequencing, providing cost-effective opportunities for clinical application. The DNA methylome also highlighted non UV-related aberrations underlying pathological differences between cutaneous and acral melanomas. Unsupervised epigenomic mapping demonstrated that non UV-mutant cutaneous melanoma more closely resembles acral rather than UV-exposed cutaneous melanoma, with the latter showing better patient prognosis than the other two forms. These gene-environment interactions in multi-ethnic backgrounds reveal translationally impactful mechanisms in melanomagenesis.
2022-05-12 | GSE202750 | GEO
Project description:The purpose of this study was to investigate the presence of a gene expression signature in BRAF V600E melanomas compared to wild type ones, all derived from sun-exposed sites. Microdissected tissues from excisional biopsies of 18 cutaneous melanomas were analyzed to detect the presence of BRAF and NRAS mutations and to profile whole genome expression by means of oligonucleotide microarrays. Class comparison methods were used to select differentially expressed genes between wild type and mutated lesions. Real Time RT-PCR and immunohistochemistry were applied to validate differences at the mRNA and protein levels on an independent cohort of samples. BRAF mutations were evidenced in 67% of melanomas. All of them consisted of the oncogenic change V600E (and the mutation event was independent of Clark's level). Data indicate that in V600E melanomas there is an over-expression of cancer stem cell markers and an upregulation of important oncogenes, like KRAS. This, together with the downregulation of genes involved in oxidative UV stress response and immuno system defense, confers an advantage to V600E melanomas compared to wt lesions. Moreover, the downregulation of topoisomerase I and CDKN2A results in an increased replicative potential associated with a decrease in senescence markers and a diminished DNA damage response. As far as the wild-type lesions, we interestingly pointed out the overexpression of PML, PIK3CA and the downregulation of two tumour suppressor genes (BRCA1 and TP73) relevant to DNA repair.
2024-12-31 | GSE22838 | GEO
Project description:<p>Acral melanoma affects world populations irrespective of skin color. It has comparatively few single nucleotide mutations, but exhibits genomic instability characterized by structural rearrangements and amplifications. As acral melanoma harbors BRAF (<a href="https://www.ncbi.nlm.nih.gov/gene/?term=BRAF">GeneID:673</a>) mutations at low frequencies, we searched for alternative therapeutic targets. We performed targeted deep sequencing of cancer-related genes on 37 acral melanomas and identified point mutations, structural rearrangements and copy number alterations. </p>
| phs001596 | dbGaP