Combinatorial Multiplex Assay Format Using Electronic Microchip Arrays and Its Potential Application in Complex Cancer Diagnostics

摘要

A key challenge in cancer treatment and prevention is early disease detection, thus facilitating effective therapeutic intervention to improve quality of life and survival. With molecular genetics playing an increasingly important role in solid tumor diagnostics, the identification of biomarkers that act as signatures of specific cancers at various developmental stages is critical to enable early definitive detection and diagnosis (1). Established cancer biomarkers can be quickly screened and detected by sensitive molecular genotyping to assess cancer risk and afford the earliest therapeutic intervention possible. Such biomarkers may also render meaningful prognostic information as well as assist in the selection of individual treatment regimens. As cancer biomarkers are discovered and characterized, the ability to quickly and economically screen large numbers of patients for a wide variety of markers is essential. This capability is further underscored by the complex and varied mutation profiles associated with cancer markers.In the present study, a combination of well-characterized gene mutations encompassing single-nucleotide polymorphisms, microdeletions, and insertions commonly found in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) was used to provide proof of principle for a method capable of simultaneously identifying multiple specific alleles by use of electronically controlled microchips. Mutation regions are amplified and applied to a single microchip test site addressed with multiple biotinylated oligonucleotide cap-ture probes. Fluorescently labeled reporter probes specific to wild-type or mutant alleles are then hybridized to the complex to provide precise genotyping. This method does not identify, but only detects the presence of any mutant alleles in a specimen; however, it permits the simultaneous screening of a large cohort of patients for a large number of different mutations. This rapid high-throughput screening platform, designated combinatorial multiplexing, can be applied to any disease-associated genes or biomarkers, especially those with complex genotype profiles, to aid in clinical …