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https://www.readbyqxmd.com/read/28205231/analysis-of-ctdna-to-predict-prognosis-and-monitor-treatment-responses-in-metastatic-pancreatic-cancer-patients
#1
He Cheng, Chen Liu, Jiahao Jiang, Guopei Luo, Yu Lu, Kaizhou Jin, Meng Guo, Zhenzhen Zhang, Jin Xu, Liang Liu, Quanxing Ni, Xianjun Yu
Cell-free circulating tumor DNA (ctDNA) in plasma has been used as a potential noninvasive biomarker for various tumors. The current study was performed to evaluate the clinical implications of ctDNA detection in patients with metastatic pancreatic cancer. Firstly, we attempted to prospectively screen a panel of 60 genes in cell-free DNA (cfDNA) from ten metastatic pancreatic cancer patients via exome sequencing. Secondly, droplet digital PCR (ddPCR) was used to identify potential mutations in a cohort of 188 patients with metastatic pancreatic cancer...
February 16, 2017: International Journal of Cancer. Journal International du Cancer
https://www.readbyqxmd.com/read/28190454/somatic-map2k1-mutations-are-associated-with-extracranial-arteriovenous-malformation
#2
Javier A Couto, August Y Huang, Dennis J Konczyk, Jeremy A Goss, Steven J Fishman, John B Mulliken, Matthew L Warman, Arin K Greene
Arteriovenous malformation (AVM) is a fast-flow, congenital vascular anomaly that may arise anywhere in the body. AVMs typically progress, causing destruction of surrounding tissue and, sometimes, cardiac overload. AVMs are difficult to control; they often re-expand after embolization or resection, and pharmacologic therapy is unavailable. We studied extracranial AVMs in order to identify their biological basis. We performed whole-exome sequencing (WES) and whole-genome sequencing (WGS) on AVM tissue from affected individuals...
January 30, 2017: American Journal of Human Genetics
https://www.readbyqxmd.com/read/28183140/correlation-between-pik3ca-mutations-in-cell-free-dna-and-everolimus-efficacy-in-hr-her2-advanced-breast-cancer-results-from-bolero-2
#3
Mary Ellen Moynahan, David Chen, Wei He, Patricia Sung, Aliaksandra Samoila, Daoqi You, Trusha Bhatt, Parul Patel, Francois Ringeisen, Gabriel N Hortobagyi, Jose Baselga, Sarat Chandarlapaty
BACKGROUND: The current analysis was performed to evaluate the impact of PIK3CA hotspot mutations on everolimus efficacy in BOLERO-2 participants, using cell-free DNA (cfDNA) from plasma samples collected at the time of patient randomisation. METHODS: PIK3CA H1047R, E545K, and E542K mutations in plasma-derived cfDNA were analysed by droplet digital PCR (ddPCR). Median PFS was estimated for patient subgroups defined by PIK3CA mutations in each treatment arm. RESULTS: Among 550 patients included in cfDNA analysis, median PFS in everolimus vs placebo arms was similar in patients with tumours that had wild-type or mutant PIK3CA (hazard ratio (HR), 0...
February 9, 2017: British Journal of Cancer
https://www.readbyqxmd.com/read/28154880/accurate-quantitation-of-circulating-cell-free-mitochondrial-dna-in-plasma-by-droplet-digital-pcr
#4
Wei Ye, Xiaojun Tang, Chu Liu, Chaowei Wen, Wei Li, Jianxin Lyu
To establish a method for accurate quantitation of circulating cell-free mitochondrial DNA (ccf-mtDNA) in plasma by droplet digital PCR (ddPCR), we designed a ddPCR method to determine the copy number of ccf-mtDNA by amplifying mitochondrial ND1 (MT-ND1). To evaluate the sensitivity and specificity of the method, a recombinant pMD18-T plasmid containing MT-ND1 sequences and mtDNA-deleted (ρ(0)) HeLa cells were used, respectively. Subsequently, different plasma samples were prepared for ddPCR to evaluate the feasibility of detecting plasma ccf-mtDNA...
February 2, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28153953/evaluation-of-a-fast-and-fully-automated-platform-to-diagnose-egfr-and-kras-mutations-in-formalin-fixed-and-paraffin-embedded-non-small-cell-lung-cancer-samples-in-less-than-one-day
#5
Laetitia Lambros, Charline Caumont, Briac Guibourg, Fanny Barel, Isabelle Quintin-Roué, Pascale Marcorelles, Jean-Philippe Merlio, Arnaud Uguen
AIMS: Searching for EGFR and KRAS mutations within non-small cell lung carcinoma (NSCLC) samples remains time-consuming and can delay treatment choices in patients with acute deterioration. We evaluated the performances of the fully automated Idylla platform to quickly detect these mutations in NSCLC samples. METHODS: We used the Idylla EGFR Mutation Assay and the Idylla KRAS Mutation Test to analyse 18 formalin-fixed paraffin-embedded NSCLC tumour samples with known EGFR and KRAS mutation status according to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) for EGFRT790M mutations...
February 2, 2017: Journal of Clinical Pathology
https://www.readbyqxmd.com/read/28152506/detection-fidelity-of-ar-mutations-in-plasma-derived-cell-free-dna
#6
Alexa Goldstein, Patricia Valda Toro, Justin Lee, John L Silberstein, Mary Nakazawa, Ian Waters, Karen Cravero, David Chu, Rory L Cochran, Minsoo Kim, Daniel Shinn, Samantha Torquato, Robert M Hughes, Aparna Pallavajjala, Michael A Carducci, Channing J Paller, Samuel R Denmeade, Bruce Kressel, Bruce J Trock, Mario A Eisenberger, Emmanuel S Antonarakis, Ben H Park, Paula J Hurley
Somatic genetic alterations including copy number and point mutations in the androgen receptor (AR) are associated with resistance to therapies targeting the androgen/AR axis in patients with metastatic castration resistant prostate cancer (mCRPC). Due to limitations associated with biopsying metastatic lesions, plasma derived cell-free DNA (cfDNA) is increasingly being used as substrate for genetic testing. AR mutations detected by deep next generation sequencing (NGS) of cfDNA from patients with mCRPC have been reported at allelic fractions ranging from over 25% to below 1%...
January 31, 2017: Oncotarget
https://www.readbyqxmd.com/read/28135250/cell-to-cell-heterogeneity-of-ewsr1-fli1-activity-determines-proliferation-migration-choices-in-ewing-sarcoma-cells
#7
G-A Franzetti, K Laud-Duval, W van der Ent, A Brisac, M Irondelle, S Aubert, U Dirksen, C Bouvier, G de Pinieux, E Snaar-Jagalska, P Chavrier, O Delattre
Ewing sarcoma is characterized by the expression of the chimeric EWSR1-FLI1 transcription factor. Proteomic analyses indicate that the decrease of EWSR1-FLI1 expression leads to major changes in effectors of the dynamics of the actin cytoskeleton and the adhesion processes with a shift from cell-to-cell to cell-matrix adhesion. These changes are associated with a dramatic increase of in vivo cell migration and invasion potential. Importantly, EWSR1-FLI1 expression, evaluated by single-cell RT-ddPCR/immunofluorescence analyses, and activity, assessed by expression of EWSR1-FLI1 downstream targets, are heterogeneous in cell lines and in tumours and can fluctuate along time in a fully reversible process between EWSR1-FLI1(high) states, characterized by highly active cell proliferation, and EWSR1-FLI1(low) states where cells have a strong propensity to migrate, invade and metastasize...
January 30, 2017: Oncogene
https://www.readbyqxmd.com/read/28125683/differences-in-amy1-gene-copy-numbers-derived-from-blood-buccal-cells-and-saliva-using-quantitative-and-droplet-digital-pcr-methods-flagging-the-pitfall
#8
Delicia Shu Qin Ooi, Verena Ming Hui Tan, Siong Gim Ong, Yiong Huak Chan, Chew Kiat Heng, Yung Seng Lee
INTRODUCTION: The human salivary (AMY1) gene, encoding salivary α-amylase, has variable copy number variants (CNVs) in the human genome. We aimed to determine if real-time quantitative polymerase chain reaction (qPCR) and the more recently available Droplet Digital PCR (ddPCR) can provide a precise quantification of the AMY1 gene copy number in blood, buccal cells and saliva samples derived from the same individual. METHODS: Seven participants were recruited and DNA was extracted from the blood, buccal cells and saliva samples provided by each participant...
2017: PloS One
https://www.readbyqxmd.com/read/28120216/a-somatic-gna11-mutation-is-associated-with-extremity-capillary-malformation-and-overgrowth
#9
Javier A Couto, Ugur M Ayturk, Dennis J Konczyk, Jeremy A Goss, August Y Huang, Steve Hann, Jennifer L Reeve, Marilyn G Liang, Joyce Bischoff, Matthew L Warman, Arin K Greene
BACKGROUND: Capillary malformation is a cutaneous vascular anomaly that is present at birth, darkens over time, and can cause overgrowth of tissues beneath the stain. The lesion is caused by a somatic activating mutation in GNAQ. In a previous study, we were unable to identify a GNAQ mutation in patients with a capillary malformation involving an overgrown lower extremity. We hypothesized that mutations in GNA11 or GNA14, genes closely related to GNAQ, also may cause capillary malformations...
January 24, 2017: Angiogenesis
https://www.readbyqxmd.com/read/28114422/a-comparative-study-of-serum-exosome-isolation-using-differential-ultracentrifugation-and-three-commercial-reagents
#10
Inas Helwa, Jingwen Cai, Michelle D Drewry, Arthur Zimmerman, Michael B Dinkins, Mariam Lotfy Khaled, Mutsa Seremwe, W Michael Dismuke, Erhard Bieberich, W Daniel Stamer, Mark W Hamrick, Yutao Liu
Exosomes play a role in cell-to-cell signaling and serve as possible biomarkers. Isolating exosomes with reliable quality and substantial concentration is a major challenge. Our purpose is to compare the exosomes extracted by three different exosome isolation kits (miRCURY, ExoQuick, and Invitrogen Total Exosome Isolation Reagent) and differential ultracentrifugation (UC) using six different volumes of a non-cancerous human serum (5 ml, 1 ml, 500 μl, 250 μl, 100 μl, and 50 μl) and three different volumes (1 ml, 500 μl and 100 μl) of six individual commercial serum samples collected from human donors...
2017: PloS One
https://www.readbyqxmd.com/read/28104621/high-prevalence-of-mutant-kras-in-circulating-exosome-derived-dna-from-early-stage-pancreatic-cancer-patients
#11
K Allenson, J Castillo, F A San Lucas, G Scelo, D U Kim, V Bernard, G Davis, T Kumar, M Katz, M J Overman, L Foretova, E Fabianova, I Holcatova, V Janout, F Meric-Bernstam, P Gascoyne, I Wistuba, G Varadhachary, P Brennan, S Hanash, D Li, A Maitra, H Alvarez
BACKGROUND: Exosomes arise from viable cancer cells and may reflect a different biology than circulating cell-free DNA (cfDNA) shed from dying tissues. We compare exosome-derived DNA (exoDNA) to cfDNA in liquid biopsies of patients with pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: Patient samples were obtained between 2003 and 2010, with clinically annotated follow up to 2015. Droplet digital PCR (ddPCR) was performed on exoDNA and cfDNA for sensitive detection of KRAS mutants at codons 12/13...
January 18, 2017: Annals of Oncology: Official Journal of the European Society for Medical Oncology
https://www.readbyqxmd.com/read/28100495/probe-free-digital-pcr-quantitative-methodology-to-measure-donor-specific-cell-free-dna-after-solid-organ-transplantation
#12
Su Kah Goh, Vijayaragavan Muralidharan, Christopher Christophi, Hongdo Do, Alexander Dobrovic
BACKGROUND: Donor-specific cell-free DNA (dscfDNA) is increasingly being considered as a noninvasive biomarker to monitor graft health and diagnose graft rejection after solid-organ transplantation. However, current approaches used to measure dscfDNA can be costly and/or laborious. A probe-free droplet digital PCR (ddPCR) methodology using small deletion/insertion polymorphisms (DIPs) was developed to circumvent these limitations without compromising the quantification of dscfDNA. This method was called PHABRE-PCR (Primer to Hybridize across an Allelic BREakpoint-PCR)...
January 18, 2017: Clinical Chemistry
https://www.readbyqxmd.com/read/28100494/quantification-of-bk-virus-standards-by-quantitative-real-time-pcr-and-droplet-digital-pcr-is-confounded-by-multiple-virus-populations-in-the-who-bkv-international-standard
#13
Allen C Bateman, Alexander L Greninger, Ederlyn E Atienza, Ajit P Limaye, Keith R Jerome, Linda Cook
BACKGROUND: The WHO recently released a BK virus (BKV) international standard. This study evaluated the WHO international standard and commercially available BKV standards by quantitative real-time PCR (qPCR) and droplet digital PCR (ddPCR). METHODS: WHO, Exact Diagnostics, Acrometrix, and Zeptometrix BKV standards were tested by qPCR and ddPCR. Two preparations of NIST BKV clones were also tested. Nucleic acid was extracted with the Roche MP96 and MPLC, followed by quantification in duplicate...
January 18, 2017: Clinical Chemistry
https://www.readbyqxmd.com/read/28088212/ultrasensitive-detection-of-oncogenic-human-papillomavirus-in-oropharyngeal-tissue-swabs
#14
Andre Isaac, Morris Kostiuk, Han Zhang, Cameron Lindsay, Fawaz Makki, Daniel A O'Connell, Jeffrey R Harris, David W J Cote, Hadi Seikaly, Vincent L Biron
BACKGROUND: The incidence of oropharyngeal squamous cell carcinoma (OPSCC) caused by oncogenic human papillomavirus (HPV) is rising worldwide. HPV-OPSCC is commonly diagnosed by RT-qPCR of HPV E6 and E7 oncoproteins or by p16 immunohistochemistry (IHC). Droplet digital PCR (ddPCR) has been recently reported as an ultra-sensitive and highly precise method of nucleic acid quantification for biomarker analysis. To validate the use of a minimally invasive assay for detection of oncogenic HPV based on oropharyngeal swabs using ddPCR...
January 14, 2017: Journal of Otolaryngology—Head & Neck Surgery
https://www.readbyqxmd.com/read/28073896/patient-specific-circulating-tumor-dna-detection-during-neoadjuvant-chemotherapy-in-triple-negative-breast-cancer
#15
Francesca Riva, Francois-Clement Bidard, Alexandre Houy, Adrien Saliou, Jordan Madic, Aurore Rampanou, Caroline Hego, Maud Milder, Paul Cottu, Marie-Paule Sablin, Anne Vincent-Salomon, Olivier Lantz, Marc-Henri Stern, Charlotte Proudhon, Jean-Yves Pierga
BACKGROUND: In nonmetastatic triple-negative breast cancer (TNBC) patients, we investigated whether circulating tumor DNA (ctDNA) detection can reflect the tumor response to neoadjuvant chemotherapy (NCT) and detect minimal residual disease after surgery. METHODS: Ten milliliters of plasma were collected at 4 time points: before NCT; after 1 cycle; before surgery; after surgery. Customized droplet digital PCR (ddPCR) assays were used to track tumor protein p53 (TP53) mutations previously characterized in tumor tissue by massively parallel sequencing...
January 10, 2017: Clinical Chemistry
https://www.readbyqxmd.com/read/28069289/liquid-biopsy-analysis-of-fgfr3-and-pik3ca-hotspot-mutations-for-disease-surveillance-in-bladder-cancer
#16
Emil Christensen, Karin Birkenkamp-Demtröder, Iver Nordentoft, Søren Høyer, Kirstin van der Keur, Kim van Kessel, Ellen Zwarthoff, Mads Agerbæk, Torben Falck Ørntoft, Jørgen Bjerggaard Jensen, Lars Dyrskjøt
BACKGROUND: Disease surveillance in patients with bladder cancer is important for early diagnosis of progression and metastasis and for optimised treatment. OBJECTIVE: To develop urine and plasma assays for disease surveillance for patients with FGFR3 and PIK3CA tumour mutations. DESIGN, SETTING, AND PARTICIPANTS: Droplet digital polymerase chain reaction (ddPCR) assays were developed and tumour DNA from two patient cohorts was screened for FGFR3 and PIK3CA hotspot mutations...
January 6, 2017: European Urology
https://www.readbyqxmd.com/read/28061461/estimation-of-cell-free-circulating-egfr-mutation-concentration-predicts-outcomes-in-nsclc-patients-treated-with-egfr-tkis
#17
Yan-Juan Zhu, Hai-Bo Zhang, Yi-Hong Liu, Fu-Li Zhang, Ya-Zhen Zhu, Yong Li, Jian-Ping Bai, Li-Rong Liu, Yan-Chun Qu, Xin Qu, Xian Chen, Yan Li, Guang-Juan Zheng
Detection of circulating tumor DNA using droplet digital polymerase chain reaction (ddPCR) is a highly-sensitive, minimally invasive alternative to serial biopsies for assessment and management of cancer. We used ddPCR to assess the utility of measuring plasma concentrations of common epidermal growth factor receptor (EGFR) mutations (L858R, exon 19 deletion, and T790M) in 57 non-small cell lung cancer (NSCLC) patients treated with EGFR tyrosine kinase inhibitors (EGFR-TKIs). High baseline plasma EGFR mutation (pEGFRmut) concentrations were associated with shorter progression-free survival (8...
January 4, 2017: Oncotarget
https://www.readbyqxmd.com/read/28059126/an-exploratory-study-of-predisposing-genetic-factors-for-digeorge-velocardiofacial-syndrome
#18
Laia Vergés, Francesca Vidal, Esther Geán, Alexandra Alemany-Schmidt, Maria Oliver-Bonet, Joan Blanco
DiGeorge/velocardiofacial syndrome (DGS/VCFS) is a disorder caused by a 22q11.2 deletion mediated by non-allelic homologous recombination (NAHR) between low-copy repeats (LCRs). We have evaluated the role of LCR22 genomic architecture and PRDM9 variants as DGS/VCFS predisposing factors. We applied FISH using fosmid probes on chromatin fibers to analyze the number of tandem repeat blocks in LCR22 in two DGS/VCFS fathers-of-origin with proven 22q11.2 NAHR susceptibility. Results revealed copy number variations (CNVs) of L9 and K3 fosmids in these individuals compared to controls...
January 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28052016/total-dna-input-is-a-crucial-determinant-of-the-sensitivity-of-plasma-cell-free-dna-egfr-mutation-detection-using-droplet-digital-pcr
#19
Yu Zhang, Yan Xu, Wei Zhong, Jing Zhao, Minjiang Chen, Li Zhang, Longyun Li, Mengzhao Wang
We evaluated the use of droplet digital PCR (ddPCR) to detect plasma cell-free DNA (cfDNA) epidermal growth factor receptor (EGFR) mutations in advanced non-small cell lung cancer (NSCLC) patients. Compared with tumor-tissue-based detection, the sensitivity of ddPCR for detecting plasma cfDNA tyrosine kinase inhibitor (TKI)-sensitizing EGFR mutations was 61.3%, the specificity was 96.7%, and the consistency rate was 81.4% (κ=0.605, 95% confidence interval: 0.501-0.706, p <0.0001). The sensitivity declined from 82...
January 24, 2017: Oncotarget
https://www.readbyqxmd.com/read/28039535/use-of-droplet-digital-pcr-for-quantitative-and-automatic-analysis-of-the-her2-status-in-breast-cancer-patients
#20
Kazutaka Otsuji, Takeshi Sasaki, Atsushi Tanaka, Akiko Kunita, Masako Ikemura, Keisuke Matsusaka, Keiichiro Tada, Masashi Fukayama, Yasuyuki Seto
PURPOSE: Digital polymerase chain reaction (dPCR) has been used to yield an absolute measure of nucleic acid concentrations. Recently, a new method referred to as droplet digital PCR (ddPCR) has gained attention as a more precise and less subjective assay to quantify DNA amplification. We demonstrated the usefulness of ddPCR to determine HER2 gene amplification of breast cancer. METHODS: In this study, we used ddPCR to measure the HER2 gene copy number in clinical formalin-fixed paraffin-embedded samples of 41 primary breast cancer patients...
December 30, 2016: Breast Cancer Research and Treatment
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