BRAF mutation testing with a novel, rapid, fully automated molecular diagnostics prototype platform.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 11086-11086
Author(s):  
Helen J. Huang ◽  
Benoit Devogelaere ◽  
Gerald Steven Falchook ◽  
Siqing Fu ◽  
Laura S. Angelo ◽  
...  

11086 Background: Mutations in the BRAF gene provide actionable targets for cancer therapy in melanoma and other tumor types. Novel, fast, and accurate diagnostic systems are needed for further implementation of personalized therapy. Methods: The molecular diagnostics (MDx) prototype platform (Biocartis, Mechelen, Belgium) is a fully integrated real-time PCR-based system with high sensitivity (1% mutant in wild-type [wt] background) and fast turnaround time (< 90 minutes), which requires no sample preparation and <2 min hands-on time. Archival formalin-fixed paraffin-embedded tumor samples (1 to 5 shavings of 10 µm) from patients (pts) with advanced cancers previously tested for V600 BRAF mutations in a CLIA-certified Molecular Diagnostic Laboratory (PCR-based sequencing or Sequenom MassARRAY) were tested for BRAF V600 mutations using the MDx prototype platform. Concordance between methods and treatment outcomes with BRAF/MEK inhibitors were analyzed. Results: Forty-seven pts (melanoma, n=26; colorectal, n=8; papillary thyroid, n=3; other cancers, n=10) with available tissue and CLIA laboratory BRAF results were selected (BRAF V600 mutant, n=37; BRAF V600 wt, n=10). Of the 40 pts for whom the same tissue block was used for MDx and CLIA, BRAF status was concordant in 38 (95%; kappa 0.87; 95% CI 0.69-1.05) of them. BRAF status by MDx was discordant with CLIA in 3 of 47 cases (mutant by CLIA, but not MDx); one discrepant case contained a different mutation subtype (resp. V600E vs. V600K/R), and in another case different tissue blocks were used for MDx vs. CLIA testing. Of 34 pts with BRAF mutations detected by MDx, 28 were treated on protocols (on the basis of the CLIA results) with BRAF/MEK inhibitors and 8 (29%) had a partial (n=7) or complete response (n=1). Of interest, 1 pt with prostate cancer (V600E by CLIA, wt by MDx) received a BRAF/MEK inhibitor and did not respond. Detailed patient characteristics, mutation types and discrepancy analysis will be presented. Conclusions: The BRAF V600 mutation MDx prototype assay is a fast (turn-around time about 1.5 hours) and simple (<2 minutes hands-on time) test to determine BRAF mutation status with 95% concordance with CLIA laboratory if identical tissue blocks are used.

2016 ◽  
Vol 9 (1) ◽  
pp. 241-245 ◽  
Author(s):  
Priscilla Denise Zepeda-Lopez ◽  
Julio Cesar Salas-Alanis ◽  
Sonia Toussaint-Caire ◽  
Daniela Gutierrez-Mendoza ◽  
Elisa Vega-Memije ◽  
...  

Background: B-Raf is a serine/threonine protein kinase activating the MAP kinase/ERK-signaling pathway. It has been shown that 50% of melanomas harbor activating BRAF mutations, with over 90% being the V600E mutation. Objective: The goal of this research was to determine the prevalence of the BRAF V600E mutation in patients from Central Mexico diagnosed with primary melanoma. Methods: Skin biopsies from 47 patients with melanoma were obtained from the dermatology department of the Hospital General ‘Dr. Manuel Gea González' in Mexico City. For BRAF mutation determination, after DNA isolation, the gene region where the mutation occurs was amplified by PCR. Subsequently, the presence or absence of the V600E mutation was detected by Sanger sequencing performed at the private molecular diagnostic laboratory Vitagénesis in Monterrey, Mexico. Results: Of the 47 patients sampled, 6.4% harbored the V600E mutation. No statistical significance was found between mutations and the type of tumor.


2019 ◽  
Vol 12 (3) ◽  
pp. 872-879
Author(s):  
Sara Bjursten ◽  
Christoffer Vannas ◽  
Stefan Filges ◽  
Florian Puls ◽  
Ankur Pandita ◽  
...  

Approximately 50% of patients with metastatic melanoma harbor an activating BRAF mutation. Tumors with activating mutation BRAF gene proliferate excessively and can be treated with targeted BRAF-inhibitors in combination with MEK inhibitors. The most common BRAF mutation occurs at amino acid position 600. Other BRAF mutations are rare and their predictive value for treatment response to BRAF/MEK inhibition is low. Here, we report on a patient with a BRAF A598_T599insV mutated melanoma, a mutation that has only been described in one previous melanoma patient in which the treatment response to BRAF/MEK inhibition was transient. Our patient had a large ulcerated metastasis that showed a durable complete response implying that BRAF/MEK inhibition should be considered a treatment option for this mutation. We analyzed circulating cell-free tumor DNA (ctDNA) carrying the BRAF A598_T599insV mutation throughout treatment. The allele frequency of BRAF A598_T599insV decreased during regression of the tumors, indicating that this method has potential to monitor treatment response. Our case demonstrates durable response to BRAF/MEK inhibition in a melanoma patient carrying a BRAF A598_T599insV mutation. In addition, we show that allele frequency analysis of A598_T599insV mutation in blood using ultrasensitive sequencing can be used to monitor treatment response.


2018 ◽  
Author(s):  
M. Verosloff ◽  
J. Chappell ◽  
K. L. Perry ◽  
J. R. Thompson ◽  
J. B. Lucks

AbstractSynthetic biology based diagnostic technologies have improved upon gold standard diagnostic methodologies by decreasing cost, increasing accuracy, and enhancing portability. However there has been little effort in adapting these technologies towards applications related to point-of-use monitoring of plant and crop health. Here, we take a step towards this vision by developing an approach that couples isothermal amplification of specific plant pathogen genomic sequences with customizable synthetic RNA regulators that are designed to trigger the production of a colorimetric output in cell-free gene expression reactions. We demonstrate our system can sense viral derived sequences with high-sensitivity and specificity, and can be utilized to directly detect viruses from infected plant material. Furthermore, we demonstrate that the entire system can operate using only body heat and naked-eye visual analysis of outputs. We anticipate these strategies to be important components of user-friendly and deployable diagnostic systems that can be configured to detect a range of important plant pathogens.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lauren Y. Cheng ◽  
Lauren E. Haydu ◽  
Ping Song ◽  
Jianyi Nie ◽  
Michael T. Tetzlaff ◽  
...  

AbstractMutations in the BRAF gene at or near the p. V600 locus are informative for therapy selection, but current methods for analyzing FFPE tissue DNA generally have a limit of detection of 5% variant allele frequency (VAF), or are limited to the single variant (V600E). These can result in false negatives for samples with low VAFs due to low tumor content or subclonal heterogeneity, or harbor non-V600 mutations. Here, we show that Sanger sequencing using the NuProbe VarTrace BRAF assay, based on the Blocker Displacement Amplification (BDA) technology, is capable of detecting BRAF V600 mutations down to 0.20% VAF from FFPE lymph node tissue samples. Comparison experiments on adjacent tissue sections using BDA Sanger, immunohistochemistry (IHC), digital droplet PCR (ddPCR), and NGS showed 100% concordance among all 4 methods for samples with BRAF mutations at ≥ 1% VAF, though ddPCR did not distinguish the V600K mutation from the V600E mutation. BDA Sanger, ddPCR, and NGS (with orthogonal confirmation) were also pairwise concordant for lower VAF mutations down to 0.26% VAF, but IHC produced a false negative. Thus, we have shown that Sanger sequencing can be effective for rapid detection and quantitation of multiple low VAF BRAF mutations from FFPE samples. BDA Sanger method also enabled detection and quantitation of less frequent, potentially actionable non-V600 mutations as demonstrated by synthetic samples.


2009 ◽  
Vol 27 (13) ◽  
pp. 2129-2136 ◽  
Author(s):  
Friedemann Honecker ◽  
Hendrik Wermann ◽  
Frank Mayer ◽  
Ad J.M. Gillis ◽  
Hans Stoop ◽  
...  

Purpose Mismatch repair (MMR) deficiency and microsatellite instability (MSI) are associated with cisplatin resistance in human germ cell tumors (GCTs). BRAF mutation (V600E) is found in MSI colorectal cancers. The role of RAS/RAF pathway mutations in GCT treatment response is unknown. Patients and Methods Two patient cohorts were investigated: 100 control GCTs (50 seminomas and 50 nonseminomas) and 35 cisplatin-based chemotherapy-resistant GCTs. MMR proteins were analyzed by immunohistochemistry, and eight microsatellite loci were examined for MSI. Tumors were assessed for specific BRAF and KRAS mutations. Results Resistant tumors showed a higher incidence of MSI than controls: 26% versus 0% in two or more loci (P < .0001). All resistant tumors were wild-type KRAS, and two controls (2%) contained a KRAS mutation. There was a significantly higher incidence of BRAF V600E mutation in resistant tumors compared with controls: 26% versus 1% (P < .0001). BRAF mutations were highly correlated with MSI (P = .006), and MSI and mutated BRAF were correlated with weak or absent staining for hMLH1 (P = .017 and P = .008). Low or absent staining of hMLH1 was correlated with promoter hypermethylation (P < .001). Tumors lacking expression of hMLH1 or MSH6 were significantly more frequent in resistant GCTs than in controls (P = .001 and 0.0036, respectively). Within the subgroup of resistant tumors, patients with MSI showed a trend to longer progression-free survival (P = .068). Conclusion We report for the first time a correlation between a gene mutation—BRAF V600E—and cisplatin resistance in nonseminomatous GCTs. Furthermore, a correlation between MMR deficiency, MSI, and treatment failure is confirmed.


Author(s):  
Deborah A. Payne ◽  
Katarina Baluchova ◽  
Graciela Russomando ◽  
Parviz Ahmad-Nejad ◽  
Cyril Mamotte ◽  
...  

Abstract Background: The International Organization for Standardization (ISO) 15189 standard provides recommendations for the postexamination reporting phase to enhance quality in clinical laboratories. The purpose of this study was to encourage a broad discussion on current reporting practices for molecular diagnostic tests by conducting a global survey of such practices. Methods: The International Federation of Clinical Chemistry and Laboratory Medicine’s Committee for Molecular Diagnostics (IFCC C-MD) surveyed laboratories on selected ISO 15189 recommendations and topics. The survey addressed the following aspects: (1) laboratory demographics, (2) report format, (3) result reporting/layout, (4) comments in report and (5) interpretation and clinical decision-making information. Additionally, participants indicated categories needing standardization. Results: Sixteen responses from laboratories located in Asia, Europe, the Middle East, North America and South America were received. Several categories yielded 100% agreement between laboratories, whereas other categories had less than or equal to 50% concordance. Participants scored “nomenclature” and “description of methodologies” as the two most frequently cited aspects needing standardization. Conclusions: The postexamination phase requires extensive and consistent communication between the laboratory, the healthcare provider and the end user. Surveyed laboratories were most likely to follow explicit ISO 15189 recommendations vs. recommendations when the term(s) “where appropriate or where applicable” was used. Interpretation and reporting of critical values varied among participants. Although the outcome of this study may not fully represent the practices of all molecular testing laboratories in countries around the world, the survey identified and specified several recommendations that are requirements for harmonized reporting in molecular diagnostics.


Plant Disease ◽  
2021 ◽  
Author(s):  
Changfeng Li ◽  
Yuliang Ju ◽  
Xun Wu ◽  
Pengfei Shen ◽  
Le Cao ◽  
...  

Bacterial wilt caused by Ralstonia solanacearum is a serious soil-borne disease that results in severe losses to tobacco (Nicotiana tabacum) production in China. In this study, a novel RPA-LFD assay for the rapid visual detection of R. solanacearum was established using recombinase polymerase amplification (RPA) and lateral-flow dipstick (LFD). The RPA-LFD assay was performed at 37°C in 30 min without complex equipment. Targeting the sequence of the RipTALI-9 gene, we designed RPA primers (Rs-rpa-F/R) and an LF probe (Rs-LF-probe) that showed high specificity to R. solanacearum. The sensitivity of RPA-LFD assay to R. solanacearum was the same as that in conventional PCR at 1 pg genomic DNA, 102 CFU/g artificially inoculated tobacco stem, and 103 CFU/g artificially inoculated soil. The RPA-LFD assay could also detect R. solanacearum from plant and soil samples collected from naturally infested tobacco fields. These results suggest that the RPA-LFD assay developed in this study is a rapid, accurate molecular diagnostic tool with high sensitivity for the detection of R. solanacearum.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 3557-3557
Author(s):  
Robin Park ◽  
Laércio Lopes da Silva ◽  
Sunggon Lee ◽  
Anwaar Saeed

3557 Background: Mismatch repair deficient/microsatellite instability high (dMMR/MSI-H) colorectal cancer (CRC) defines a molecular subtype with distinct clinicopathologic characteristics including an excellent response to immunotherapy. Although BRAF mutations are established as a negative prognostic marker in CRC, whether they retain their negative prognostic impact in or alter the response to immunotherapy in dMMR/MSI-H CRC remains unknown. Herein, we present a systematic review and meta-analysis of the impact of BRAF mutations on the overall survival (OS) and immune checkpoint inhibitor (ICI) response in dMMR/MSI-H CRC. Methods: Studies published from inception to 26 January 2021 were searched in PubMed, Embase, and major conference proceedings (AACR, ASCO, and ESMO). Eligible studies included the following: 1) observational studies reporting outcomes based on BRAF mutation status in dMMR/MSI-H CRC patients and 2) experimental studies of ICI reporting outcomes based on BRAF mutation status in dMMR/MSI-H CRC patients. A summary hazard ratio (HR) was calculated for OS in BRAF mutated ( BRAFmut) vs. BRAF wild type ( BRAFwt) patients (pts) with the random effects meta-analysis (REM). A summary odds ratio (OR) was calculated for objective response rate (ORR) in BRAFmut vs. BRAFwt pts treated with ICI with the REM. Results: Database search conducted according to PRISMA guidelines found 4221 studies in total. Initial screening identified 30 studies and after full-text review, 9 studies (N = 4158 pts) were included for the meta-analysis of prognosis (analysis A) and 3 studies (N = 178 pts) were included for the meta-analysis of ICI response (analysis B). The outcome measures are summarized in the table below. Analysis A showed that in stage I-IV dMMR/MSI-H CRC pts, BRAFmut was associated with worse OS than BRAFwt (HR 1.57, 1.23-1.99). The heterogeneity was low (I2 = 21%). Subgroup analysis showed no significant difference in the prognostic impact of BRAF mutation status between stage IV only and stage I-IV CRC pts. Analysis B showed no difference in ORR (OR 1.04, 0.48-2.25) between BRAFmut vs. BRAFwt dMMR/MSI-H pts who received ICI. The heterogeneity was low (I2 = 0%). Conclusions: BRAF mutations retain their negative prognostic impact in dMMR/MSI-H stage I-IV and stage IV CRC but are not associated with differential ICI response. Limitations include the following: analysis A was based on retrospective studies; also, the impact of BRAF status on the survival outcome of ICI could not be assessed due to limited number of studies.[Table: see text]


2015 ◽  
Vol 4 (2) ◽  
pp. 12-30 ◽  
Author(s):  
Niki Margari ◽  
Abraham Pouliakis ◽  
Aris Spathis ◽  
Emmanouil Mastorakis ◽  
Efthymios Karakostas ◽  
...  

The assessment of BRAF V600E mutations is important for prognosis and treatment of Papillary Thyroid Carcinomas (PTC), the standard methods for their identification are molecular biology techniques. In this study, the potential of image morphometry applied to cell nuclei and sequentially the use of a Classification And Regression Tree (CART) is investigated, in order to: identify morphometric features useful to characterize BRAF mutations, and to eventually produce an algorithm identifying BRAF mutation status. The 140 studied cases had histological confirmation and known BRAF mutation status identified via real-time PCR. The analysis revealed that nuclear features contributing to BRAF mutation status identification via the CART model are related mostly to nuclear color. According to the results there is evidence that BRAF V600E mutations can be identified by measurable image features. Therefore, the proposed method is useful for quality control of BRAF V600E mutations on cytological slides, can serve as alternative to PCR method and may be used for remote assessment.


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