Molecular Diagnostics of Biofluid-derived Extracellular Vesicles for Brain TumorsThursday, 18 September 2014 at 17:15 Add to Calendar ▼2014-09-18 17:15:002014-09-18 18:15:00Europe/LondonMolecular Diagnostics of Biofluid-derived Extracellular Vesicles for Brain TumorsExosomes and Single Cell Analysis Summit in San Diego, California, USASan Diego, California, USASELECTBIOenquiries@selectbiosciences.com Fluid biopsies are powerful because they allow for molecular characterization of tumors in a minimally invasive fashion. All tumors secrete extracellular vesicles (EVs) that are relatively stable in biofluids and can provide important information about the disease state. Tumor derived EVs are a minor component in a pool of normal cell derived EVs, so detecting tumor markers is a major challenge. Assay sensitivity and specificity are particularly imperative when they are used as companion diagnostic or for trial stratification. Brain tumors hold an extra level of challenge because of their enclosed location in the brain. We sought to determine the presence and levels of the mutant isocitrate dehydrogenase 1 (IDH1) in the plasma and cerebrospinal fluid (CSF) of patients with glioma. We determined a robust sensitivity of 1 mutant copy in 10,000 wild type copies when using spiked in RNA from mutant and wild type cells. We also detected the mutant IDH1 in 63% of CSF samples. We also characterized plasma and serum derived EVs for the presence of mRNA and miRNA species using the miScript miRNA PCR Arrays (Qiagen) for serum and plasma, and the RT2 ProfilerTM PCR array Human Cancer Pathway FinderTM (Qiagen) for mRNA and we report differential EV signatures in glioblastoma patients compared to controls. We are currently analyzing plasma samples from IDH1 mutant glioma patients. This finding expands the diagnostic potential of circulating tumor EVs and demonstrates the great promise for this technology in next-generation companion diagnostics and mutational profiling of individual tumors. |