Project description:An improved understanding of the molecular pathogenesis of brain metastases, one of the most common and devastating complications of advanced melanoma, may identify and prioritize rational therapeutic approaches for this disease. In particular, the identification of molecular differences between brain and extracranial metastases would support the need for the development of organ-specific therapeutic approaches. Hotspot mutations, copy number variations (CNV), global mRNA expression patterns, and protein expression and activation, quantitatively analyzed by molecular inversion probe arrays, microarrays and reverse phase protein array (RPPA) were evaluated in pairs of melanoma brain metastases and extracranial metastases from patients who had undergone surgical resection for both types of tumors. Seventy-two samples from 52 brain (except for patient 01, who had a spinal cord metastasis) and extracranial metastases of melanoma were analyzed. Available biological replicates (different parts of the same tumor) were included.
Project description:An improved understanding of the molecular pathogenesis of brain metastases, one of the most common and devastating complications of advanced melanoma, may identify and prioritize rational therapeutic approaches for this disease. In particular, the identification of molecular differences between brain and extracranial metastases would support the need for the development of organ-specific therapeutic approaches. Hotspot mutations, copy number variations (CNV), global mRNA expression patterns, and protein expression and activation, quantitatively analyzed by molecular inversion probe arrays, microarrays and reverse phase protein array (RPPA) were evaluated in pairs of melanoma brain metastases and extracranial metastases from patients who had undergone surgical resection for both types of tumors.
Project description:This is a whole exome study of brain metastases in melanoma. We are studying the genomic evolution of primary cutaneous melanoma to brain met in patients with brain-only metastatic disease. We are also looking at the genomic heterogeneity in patients with temporally, anatomically and regionally separated brian metastases.
Project description:Melanoma brain metastases (MBM) and leptomeningeal metastases (LMM) are two manifestations of melanoma CNS metastasis with vastly different survival outcomes. Using single cell RNA-Seq analysis we uncovered a unique, immune-suppressed T-cell landscape in the LMM microenvironment distinct from that of brain and skin metastases. An LMM patient with an unusually long survival demonstrated an immune repertoire that was distinct from those of poor survivors and more similar to CSF from non-LMM patients. Upon response to PD-1 therapy, this extreme responder showed increased levels of T-cells and dendritic cells in their CSF, whereas poor survivors showed little improvement in their T-cell responses. In MBM patients, systemic therapy was associated with increased immune infiltrate, with similar T-cell transcriptional diversity noted between skin metastases and MBM - suggestive of immune cell trafficking into the brain. A correlation analysis across the entire immune landscape identified the presence of a rare population of dendritic cells (DC3s) that correlated with increased overall survival and positively regulated the immune environment through modulation of activated T-cells and MHC expression. Our study provides the first atlas of two distinct sites of melanoma CNS metastases and identifies rare populations of cells that underlie the biology of this devastating disease.
Project description:We performed single nuclei and spatial transcriptomic sequencing on a cohort of solid tumor human brain metastasis specimens resected at Duke University Medical Center from 1998 to 2022. This includes 23 single nuclei specimens, 12 Visium standard specimens, and 4 Xenium specimens. These samples encompass metastases from lung cancer, breast cancer, melanoma, and sarcoma primaries. Analysis of these data revealed novel tumor-microenvironment cell-cell interactions associated with patient survival.
Project description:We performed single nuclei and spatial transcriptomic sequencing on a cohort of solid tumor human brain metastasis specimens resected at Duke University Medical Center from 1998 to 2022. This includes 23 single nuclei specimens, 12 Visium standard specimens, and 4 Xenium specimens. These samples encompass metastases from lung cancer, breast cancer, melanoma, and sarcoma primaries. Analysis of these data revealed novel tumor-microenvironment cell-cell interactions associated with patient survival.
Project description:An improved understanding of the molecular pathogenesis of brain metastases, one of the most common and devastating complications of advanced melanoma, may identify and prioritize rational therapeutic approaches for this disease. In particular, the identification of molecular differences between brain and extracranial metastases would support the need for the development of organ-specific therapeutic approaches. Hotspot mutations, copy number variations (CNV), global mRNA expression patterns, and protein expression and activation, quantitatively analyzed by mass-array genotyping, molecular inversion probe arrays, microarrays and reverse phase protein array (RPPA) were evaluated in pairs of melanoma brain metastases and extracranial metastases from patients who had undergone surgical resection for both types of tumors. Somatic copy number variation (CNV) in 47 melanoma brain metastases (BM, except for patient 01, who had a spinal cord metastasis) and extracranial metastases (EM) were analyzed by molecular inversion probe (MIP) array (Affymetrix OncoScan FFPE Express 2.0). DNA were extracted from regions with >70% viable tumor cells from formalin-fixed and paraffin-embedded (FFPE) tissues. Of the 47 tumor samples, 22 were matched BM and EM from the same patients. In addition, 24 DNA samples from normal tissues were included as diploid controls.