title: Direct detection of circulating free DNA extracted from serum samples of breast cancer using locked nucleic acid molecular beacon.
abstract: As an emerging noninvasive blood biomarker, circulating free DNA (cfDNA) can be utilized to assess diagnosis, progression and evaluate prognosis of cancer. However, cfDNAs are not "naked", they can be part of complexes, or are bound to the surface of the cells via proteins, which make the detection more challenging. Here, a simple method for the detection of Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) DNA exacted from serum of breast cancer (BC) has been developed using a novel locked nucleic acid molecular beacon (LNA-MB). In order to enhance the stability and detection efficiency of the probe in biofluids, we design a shared-stem molecular beacon containing a 27-mer loop and a 4-mer stem with DNA/LNA alternating bases. The fluorescence is released in the presence of target. The detection procedure is simple and can be completed within 1h. This method shows a sensitive response to UHRF1 DNA with a dynamic range of 3 orders of magnitude. The limit of detection is 11nM (S/N=3) with excellent selectivity. It can discriminate UHRF1 DNA from three-base mismatched DNA with a high specificity. More importantly, this method can distinguish the expression of serum UHRF1 DNA among 5 breast cancer patients and 5 healthy controls. The mentioned superiority may suggest that this assay can be served as a promising noninvasive detection tool for early BC diagnosis and monitoring.
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Gui
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, PR China.
authors.forename: Quanbo
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China.
authors.forename: Jinchang
authors.initials: J
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China.
authors.forename: Mingchen
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China.
authors.forename: Lili
authors.initials: L
authors.lastname: Yu
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China.
authors.forename: Tang
authors.initials: T
authors.lastname: Xun
authors.affiliation: Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing Medical University Cancer Hospital & Jiangsu Cancer Hospital, Nanjing 210009, PR China. Electronic address: yanfeng2007@sohu.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, PR China. Electronic address: hxju@nju.edu.cn.
authors.forename: Huangxian
authors.initials: H
authors.lastname: Ju
mesh_terms: D001943:Breast Neoplasms; D004247:DNA; D006801:Humans; D009841:Oligonucleotides; D011379:Prognosis
chemical_list: D009841:Oligonucleotides; C477371:locked nucleic acid; D004247:DNA
keywords: Circulating free DNA; Direct detection; Locked nucleic acid; Molecular beacon; Noninvasive