RESUMO
PURPOSE: To evaluate clinico-pathological and molecular prognostic factors in a well-defined series of posterior uveal melanoma (UM) with focus on chromosomal aberrations and mutations in the GNAQ, GNA11 and BRCA1-associated protein 1 (BAP1) genes. METHODS: Formalin-fixed paraffin-embedded (FFPE) tissue samples were obtained from 50 consecutive eyes enucleated for UM between 1993 and 2005. The material was tested for loss of chromosome 3 and gain of chromosome 8q gene signatures by selective molecular gene markers using multiplex ligation-dependent probe amplification (MLPA), and for DNA mutations in the GNAQ, GNA11 and BAP1 genes. RESULTS: After a mean follow-up of 83 months (range, 8-205 months), 21 patients had died of metastatic UM and 16 patients of other causes. Tumour diameter, ciliary body involvement, mixed/epithelioid cell types, mitotic index, Ki-67 proliferation index, loss of chromosome 3 and gain of chromosome 8q showed statistically significant associations with metastatic disease. There were no significant differences in the prevalence of GNAQ and GNA11 mutations between patients with or without metastatic disease. Mutational analysis of the BAP1 gene was performed in 32 primary UM and in five UM liver metastases. Nine different BAP1 missense mutations were identified. BAP1 mutations were not more common in metastasizing than in nonmetastasizing UM. CONCLUSION: The molecular gene markers showing loss of chromosome 3 and gain of 8q gene signatures were associated with an increased risk of metastatic disease. BRCA1-associated protein 1 (BAP1) gene mutation status had no prognostic significance. The frequency and spectrum of BAP1 mutations in UM may be more dependent on ethnicity and demographic variables than hitherto considered.
Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 3/genética , DNA de Neoplasias/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Melanoma/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Análise Mutacional de DNA , Feminino , Seguimentos , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Humanos , Masculino , Melanoma/metabolismo , Melanoma/secundário , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Mutação , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo , Úvea/metabolismo , Úvea/patologia , Neoplasias Uveais/metabolismo , Neoplasias Uveais/secundário , Adulto JovemRESUMO
Recent studies have detailed the genomic landscape of primary endometrial cancers, but the evolution of these cancers into metastases has not been characterized. We performed whole-exome sequencing of 98 tumor biopsies including complex atypical hyperplasias, primary tumors and paired abdominopelvic metastases to survey the evolutionary landscape of endometrial cancer. We expanded and reanalyzed The Cancer Genome Atlas (TCGA) data, identifying new recurrent alterations in primary tumors, including mutations in the estrogen receptor cofactor gene NRIP1 in 12% of patients. We found that likely driver events were present in both primary and metastatic tissue samples, with notable exceptions such as ARID1A mutations. Phylogenetic analyses indicated that the sampled metastases typically arose from a common ancestral subclone that was not detected in the primary tumor biopsy. These data demonstrate extensive genetic heterogeneity in endometrial cancers and relative homogeneity across metastatic sites.