Despite outstanding advances in diagnosis and the treatment of primary uveal melanoma (UM), nearly 50% of UM patients develop metastases via hematogenous dissemination, driven by the epithelial-mesenchymal transition (EMT). Despite the failure in UM to date, a liquid biopsy may offer a feasible non-invasive approach for monitoring metastatic disease progression and addressing protracted dormancy. To detect circulating tumor cells (CTCs) in UM patients, we evaluated the mRNA expression of EMT-associated transcription factors in CD45-depleted blood fraction, using qRT-PCR. ddPCR was employed to assess UM-specific GNA11, GNAQ, PLCβ4, and CYSLTR2 mutations in plasma DNA. Moreover, microarray analysis was performed on total RNA isolated from tumor tissues to estimate the prognostic value of EMT-associated gene expression. In total, 42 primary UM and 11 metastatic patients were enrolled. All CD45-depleted samples were negative for CTC when compared to the peripheral blood fraction of 60 healthy controls. Tumor-specific mutations were detected in the plasma of 21.4% patients, merely, in 9.4% of primary UM, while 54.5% in metastatic patients. Unsupervised hierarchical clustering of differentially expressed EMT genes showed significant differences between monosomy 3 and disomy 3 tumors. Newly identified genes can serve as non-invasive prognostic biomarkers that can support therapeutic decisions.

Bernard-Soulier syndrome (BSS) is a rare inherited disorder characterized by unusually large platelets, low platelet count, and prolonged bleeding time. BSS is usually inherited in an autosomal recessive (AR) mode of inheritance due to a deficiency of the GPIb-IX-V complex also known as the von Willebrand factor (VWF) receptor. We investigated a family with macrothrombocytopenia, a mild bleeding tendency, slightly lowered platelet aggregation tests, and suspected autosomal dominant (AD) inheritance. We have detected a heterozygous GP1BA likely pathogenic variant, causing monoallelic BSS. A germline GP1BA gene variant (NM_000173:c.98G > A:p.C33Y), segregating with the macrothrombocytopenia, was detected by whole-exome sequencing. In silico analysis of the protein structure of the novel GPIbα variant revealed a potential structural defect, which could impact proper protein folding and subsequent binding to VWF. Flow cytometry, immunoblot, and electron microscopy demonstrated further differences between p.C33Y GP1BA carriers and healthy controls. Here, we provide a detailed insight into its clinical presentation and phenotype. Moreover, the here described case first presents an mBSS patient with two previous ischemic strokes.

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