title: Amplification-Free Detection of Circulating microRNA Biomarkers from Body Fluids Based on Fluorogenic Oligonucleotide-Templated Reaction between Engineered Peptide Nucleic Acid Probes: Application to Prostate Cancer Diagnosis.
abstract: Highly abundant in cells, microRNAs (or miRs) play a key role as regulators of gene expression. A proportion of them are also detectable in biofluids making them ideal noninvasive biomarkers for pathologies in which miR levels are aberrantly expressed, such as cancer. Peptide nucleic acids (PNAs) are engineered uncharged oligonucleotide analogues capable of hybridizing to complementary nucleic acids with high affinity and high specificity. Herein, novel PNA-based fluorogenic biosensors have been designed and synthesized that target miR biomarkers for prostate cancer (PCa). The sensing strategy is based on oligonucleotide-templated reactions where the only miR of interest serves as a matrix to catalyze an otherwise highly unfavorable fluorogenic reaction. Validated in vitro using synthetic RNAs, these newly developed biosensors were then shown to detect endogenous concentrations of miR in human blood samples without the need for any amplification step and with minimal sample processing. This low-cost, quantitative, and versatile sensing technology has been technically validated using gold-standard RT-qPCR. Compared to RT-qPCR however, this enzyme-free, isothermal blood test is amenable to incorporation into low-cost portable devices and could therefore be suitable for widespread public screening.
authors: Department of Bioengineering, Imperial College London , South Kensington Campus, London SW72AZ, U.K.|Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Gavin A D
authors: GA
authors: Metcalf
authors: Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Akifumi
authors: A
authors: Shibakawa
authors: Department of Bioengineering, Imperial College London , South Kensington Campus, London SW72AZ, U.K.
authors: Hinesh
authors: H
authors: Patel
authors: Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Ailsa
authors: A
authors: Sita-Lumsden
authors: Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Andrea
authors: A
authors: Zivi
authors: Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Nona
authors: N
authors: Rama
authors: Department of Surgery and Cancer, Imperial College London , Hammersmith Hospital Campus, London W120NN, U.K.
authors: Charlotte L
authors: CL
authors: Bevan
authors: Department of Bioengineering, Imperial College London , South Kensington Campus, London SW72AZ, U.K.
authors: Sylvain
authors: S
authors: Ladame
mesh_terms: D015415:Biomarkers / Q000097:blood*; D015374:Biosensing Techniques; D000074166:Circulating MicroRNA / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D003374:Coumarins / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D008297:Male; D009693:Nucleic Acid Hybridization; D015341:Nucleic Acid Probes / Q000737:chemistry* / Q000378:metabolism; D009841:Oligonucleotides / Q000737:chemistry; D020135:Peptide Nucleic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D020641:Polymorphism, Single Nucleotide; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D015415:Biomarkers; D000074166:Circulating MicroRNA; D003374:Coumarins; D005456:Fluorescent Dyes; D015341:Nucleic Acid Probes; D009841:Oligonucleotides; D020135:Peptide Nucleic Acids; C030123:coumarin