Publications by authors named "Margaret I Sanchez"

PRAME is a CUL2 ubiquitin ligase subunit that is normally expressed in the testis but becomes aberrantly overexpressed in many cancer types in association with aneuploidy and metastasis. Here, we show that PRAME is expressed predominantly in spermatogonia around the time of meiotic crossing-over in coordination with genes mediating DNA double strand break repair. Expression of PRAME in somatic cells upregulates pathways involved in meiosis, chromosome segregation and DNA repair, and it leads to increased DNA double strand breaks, telomere dysfunction and aneuploidy in neoplastic and non-neoplastic cells.

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PRAME is a CUL2 ubiquitin ligase subunit that is normally expressed in the testis but becomes aberrantly overexpressed in many cancer types in association with aneuploidy and metastasis. Here, we show that PRAME is expressed predominantly in spermatogonia around the time of meiotic crossing-over in coordination with genes mediating DNA double strand break repair. Expression of PRAME in somatic cells upregulates pathways involved in meiosis, chromosome segregation and DNA repair, and it leads to increased DNA double strand breaks, telomere dysfunction and aneuploidy in neoplastic and non-neoplastic cells.

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Uveal melanoma (UM) is the most common primary cancer of the eye and is associated with a high rate of metastatic death. UM can be stratified into two main classes based on metastatic risk, with class 1 UM having a low metastatic risk and class 2 UM having a high metastatic risk. Class 2 UM have a distinctive genomic, transcriptomic, histopathologic, and clinical phenotype characterized by biallelic inactivation of the tumor-suppressor gene, an immune-suppressive microenvironment enriched for M2-polarized macrophages, and poor response to checkpoint-inhibitor immunotherapy.

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Uveal melanoma (UM) is the most common cancer of the eye and leads to metastatic death in up to half of patients. Genomic prognostic biomarkers play an important role in clinical management in UM. However, research has been conducted almost exclusively in patients of European descent, such that the association between genetic admixture and prognostic biomarkers is unknown.

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Article Synopsis
  • Uveal melanoma (UM) is a serious type of cancer that doesn’t respond well to some new treatments called checkpoint immunotherapy.
  • Scientists studied a lot of cells from UM tumors to learn more about how they work and found lots of different types of immune cells in the tumors.
  • They discovered that a specific immune marker called LAG3 might be important for treating patients with a higher risk of UM in the future.
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Ocular melanocytosis is the most important predisposing condition for the eye cancer uveal melanoma (UM). Here, we present a patient who developed UM arising within ocular melanocytosis who was treated with enucleation (eye removal), which provided an invaluable opportunity to interrogate both the UM and adjacent uveal tissue containing the melanocytosis using whole-exome and deep-targeted sequencing. This analysis revealed a clonal mutation in the melanocytosis, confirming that this is indeed a neoplastic condition and explaining why it predisposes to UM.

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Background: Acral lentiginous melanoma has increased mortality compared with other melanoma subtypes and disproportionately affects ethnic minorities. Acral melanocytic lesions have not been well studied in diverse populations of the United States.

Objective: We sought to assess the prevalence, awareness, and dermoscopic patterns of acral melanocytic lesions in skin-of-color and non-Hispanic white patients.

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The majority of melanoma mutations are C>T transitions, and most bear UV signatures. However, other process may contribute to the high C>T mutation rate. Okura et al.

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Importance: Mutations driving melanoma growth have diagnostic, prognostic, and therapeutic implications. Traditional classification systems do not correlate optimally with underlying melanoma growth-promoting mutations. Our objective was to determine whether unique dermoscopic growth patterns directly correlate with driving mutations.

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Article Synopsis
  • - Melanocytic neoplasms are a varied group of tumors that can be either benign or malignant, showing different clinical characteristics across cases.
  • - Traditional theories suggest that these tumors originate from epidermal melanocytes, but this doesn't align with many clinical observations.
  • - Factors such as genetics, the biological state and location of mutated cells, and environmental influences are important in understanding the development of these neoplasms, and the text aims to explore models and research challenges in this area.
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It is generally accepted that cutaneous nevogenesis is a localized event that occurs exclusively in the dermis and/or epidermis. However, the discovery of nevocytes circulating in the peripheral blood suggests that other, more systemic, benign metastatic processes could also be involved. The theoretical role of lymphatic and hematogenous dissemination of loosely adherent, immature nevus progenitor cells in the development of nodal nevi and eruptive melanocytic nevi will be reviewed.

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Melanomas and nevi share many of the same growth-promoting mutations. However, melanomas grow relentlessly while benign nevi eventually undergo growth arrest and stabilize. The difference in their long-term growth potential may be attributed to activation of cellular senescence pathways.

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Despite recent advances, the biology underlying nevogenesis remains unclear. Activating mutations in NRAS, HRAS, BRAF, and GNAQ have been identified in benign nevi. Their presence roughly correlates with congenital, Spitz, acquired, and blue nevi, respectively.

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