PURPOSE: To develop a molecular tool to detect circulating tumor-derived DNA (ctDNA) in the plasma from patients with uveal melanoma as a marker of tumor burden and monitor treatment efficacy. EXPERIMENTAL DESIGN: A real-time PCR was developed on the basis of bidirectional pyrophosphorolysis-activated polymerization (bi-PAP) for the quantification of ctDNA using 3'blocked primer pairs specific for the 3 recurrent mutually exclusive mutations of Gα subunits GNAQ and GNA11. RESULTS: Sensitivity and specificity of bi-PAP were assessed on serial dilutions of tumor DNA in normal DNA for the 3 recurrent mutations. Each assay could detect a single mutated molecule per reaction, whereas 10(4) copies of normal DNA were not detected. The ctDNA was readily detected in plasma of mice bearing uveal melanoma xenografts in amounts proportional to circulating human DNA. Finally, plasma was almost always found positive (20 of 21 tested patients) in a prospective analysis of patients with metastatic uveal melanoma. CONCLUSIONS: Bi-PAP assays detect and quantify ctDNA in patients with metastatic uveal melanoma. A prospective study is ongoing to assess the clinical usefulness of ctDNA level in uveal melanoma.
PURPOSE: To develop a molecular tool to detect circulating tumor-derived DNA (ctDNA) in the plasma from patients with uveal melanoma as a marker of tumor burden and monitor treatment efficacy. EXPERIMENTAL DESIGN: A real-time PCR was developed on the basis of bidirectional pyrophosphorolysis-activated polymerization (bi-PAP) for the quantification of ctDNA using 3'blocked primer pairs specific for the 3 recurrent mutually exclusive mutations of Gα subunits GNAQ and GNA11. RESULTS: Sensitivity and specificity of bi-PAP were assessed on serial dilutions of tumor DNA in normal DNA for the 3 recurrent mutations. Each assay could detect a single mutated molecule per reaction, whereas 10(4) copies of normal DNA were not detected. The ctDNA was readily detected in plasma of mice bearing uveal melanoma xenografts in amounts proportional to circulating human DNA. Finally, plasma was almost always found positive (20 of 21 tested patients) in a prospective analysis of patients with metastatic uveal melanoma. CONCLUSIONS: Bi-PAP assays detect and quantify ctDNA in patients with metastatic uveal melanoma. A prospective study is ongoing to assess the clinical usefulness of ctDNA level in uveal melanoma.
Authors: P Mokarram; M Rismanchi; M Alizadeh Naeeni; S Mirab Samiee; M Paryan; A Alipour; Z Honardar; S Kavousipour; F Naghibalhossaini; Z Mostafavi-Pour; A Monabati; S V Hosseni; S A Shamsdin Journal: Mol Biol Rep Date: 2014-01-23 Impact factor: 2.316
Authors: Chris Karlovich; Jonathan W Goldman; Jong-Mu Sun; Elaina Mann; Lecia V Sequist; Krzysztof Konopa; Wei Wen; Philipp Angenendt; Leora Horn; David Spigel; Jean-Charles Soria; Benjamin Solomon; D Ross Camidge; Shirish Gadgeel; Cloud Paweletz; Lin Wu; Sean Chien; Patrick O'Donnell; Shannon Matheny; Darrin Despain; Lindsey Rolfe; Mitch Raponi; Andrew R Allen; Keunchil Park; Heather Wakelee Journal: Clin Cancer Res Date: 2016-01-08 Impact factor: 12.531