scholarly journals TruSight Oncology 500: Enabling Comprehensive Genomic Profiling and Biomarker Reporting with Targeted Sequencing

2020 ◽  
Author(s):  
Chen Zhao ◽  
Tingting Jiang ◽  
Jin Hyun Ju ◽  
Shile Zhang ◽  
Jenhan Tao ◽  
...  

AbstractBackgroundAs knowledge of mechanisms that drive the development of cancer grows, there has been corresponding growth in therapies specific to a mechanism. While these therapies show improvements in patient outcomes, they can be expensive and are effective only for a subset of patients. These treatments drive interest in research focused on the assignment of cancer therapies based on aberrations in individual genes or biomarkers that assess the broader mutational landscape, including microsatellite instability (MSI) and tumor mutational burden (TMB).MethodsHere we describe the TruSight™ Oncology 500 (TSO500; Research Use Only) bioinformatics workflow. This tumor-only approach leverages the next-generation sequencing-based assay TSO500 to enable high fidelity determination of DNA variants across 523 cancer-relevant genes, as well as MSI status and TMB in formalin-fixed paraffin-embedded (FFPE) samples.ResultsThe TSO500 bioinformatic workflow integrates unique molecular identifier (UMI)-based error correction and a dual approach variant filtering strategy that combines statistical modeling of error rates and database annotations to achieve detection of variants with allele frequency approaching 5% with 99.9998% per base specificity and 99% sensitivity in FFPE samples representing a variety of tumor types. TMB determined using the tumor-only workflow of TSO500 correlated well with tumor-normal (N =170, adjusted R2=0.9945) and whole-exome sequencing (N=108, adjusted R2=0.933). Similarly, MSI status determined by TSO500 showed agreement (N=106, 98% agreement) with a MSI-PCR assay.ConclusionTSO500 is an accurate tumor-only workflow that enables researchers to systematically characterize tumors and identify the next generation of clinical biomarkers.

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yi Luo ◽  
Zhenzhen Zhang ◽  
Jianfan Liu ◽  
Linqing Li ◽  
Xuezheng Xu ◽  
...  

Melanoma is a human skin malignant tumor with high invasion and poor prognosis. The limited understanding of genomic alterations in melanomas in China impedes the diagnosis and therapeutic strategy selection. We conducted comprehensive genomic profiling of melanomas from 39 primary and metastatic formalin-fixed paraffin-embedded (FFPE) samples from 27 patients in China based on an NGS panel of 223 genes. No significant difference in gene alterations was found between primary and metastasis melanomas. The status of germline mutation, CNV, and somatic mutation in our cohort was quite different from that reported in Western populations. We further delineated the mutation patterns of 4 molecular subgroups (BRAF, RAS, NF1, and Triple-WT) of melanoma in our cohort. BRAF mutations were more frequently identified in melanomas without chromic sun-induced damage (non-CSD), while RAS mutations were more likely observed in acral melanomas. NF1 and Triple-WT subgroups were unbiased between melanomas arising in non-CSD and acral skin. BRAF, RAS, and NF1 mutations were significantly associated with lymph node metastasis or presence of ulceration, implying that these cancer driver genes were independent prognostic factors. In summary, our results suggest that mutational profiles of malignant melanomas in China are significantly different from Western countries, and both gene mutation and amplification play an important role in the development and progression of melanomas.


2020 ◽  
Vol 73 (9) ◽  
pp. 602-604
Author(s):  
Silvia Bessi ◽  
Francesco Pepe ◽  
Marco Ottaviantonio ◽  
Pasquale Pisapia ◽  
Umberto Malapelle ◽  
...  

In the present study, we analysed 44 formalin fixed paraffin embedded (FFPE) from different solid tumours by adopting two different next generation sequencing platforms: GeneReader (QIAGEN, Hilden, Germany) and Ion Torrent (Thermo Fisher Scientific, Waltham, Massachusetts, USA). We highlighted a 100% concordance between the platforms. In addition, focusing on variant detection, we evaluated a very good agreement between the two tests (Cohen’s kappa=0.84) and, when taking into account variant allele fraction value for each variant, a very high concordance was obtained (Pearson’s r=0.94). Our results underlined the high performance rate of GeneReader on FFPE samples and its suitability in routine molecular predictive practice.


2020 ◽  
Vol 38 (4_suppl) ◽  
pp. 757-757
Author(s):  
Amanda Hemmerich ◽  
Claire I. Edgerly ◽  
Daniel Duncan ◽  
Richard Huang ◽  
Natalie Danziger ◽  
...  

757 Background: Pancreas ductal adenocarcinomas (PDA) has a 5-year survival rate of 6% with a need for new therapeutic options. The approval of pembrolizumab for some gastrointestinal cancers shows the potential of immunotherapy (IMT) in PDA. We evaluated the IMT-associated biomarkers of PD-L1 expression, tumor mutational burden (TMB), microsatellite instability (MSI) and PD-L1 amplification in PDAs. Methods: 746 formalin-fixed paraffin embedded samples were evaluated for PD-L1 IHC using the Dako 22C3 pharmDx assay and scored using tumor proportion score (TPS). The cases had comprehensive genomic profiling (CGP) via DNA sequencing, using a hybrid-capture next-generation sequencing assay (FoundationOne and FoundationOneCDx) for genomic alterations (GAs), TMB, and MSI. Results: PD-L1 was positive (TPS ≥ 1%) in 29% (214/746) and negative in 71% (532/746). 43/214 (20%) of positive cases were high positive (TPS ≥ 50%). TMB (590 cases) had a mean of 3.20, 3.46, and 3.61 mutations/Mb for PD-L1 negative, positive, and high positive groups. 3 hypermutated (TMB ≥ 20) were negative for PD-L1 expression. 3/581 cases were MSI-high with a high TMB score (average 23.53 mutations/Mb). 2 MSI-high cases were negative for PD-L1 and 1 was high positive. PD-L1 amplification was not detected (0/746). Only BCOR was significantly different between PD-L1 high positive and PD-L1 negative tumors (Table). Conclusions: Of 729 PDA cases, 29% were positive (TPS ≥ 1%) for PD-L1 expression while only 6% of all cases showed a high level of PD-L1 expression on tumor cells. TMB high (3/729) and MSI-High (3/729) cases were rare. Only 2 of the TMB high cases were also MSI-high. PD-L1 amplification was not detected. Comparing GAs in PD-L1 high positive vs negative cases was only significantly different for BCOR. Further investigation is needed to see if a combined positive score of PD-L1 expression may identify a subset of patients with PDA who are more likely to respond to IMT. [Table: see text]


2018 ◽  
Vol 36 (4_suppl) ◽  
pp. 271-271
Author(s):  
Ben George ◽  
Joel R. Greenbowe ◽  
Andrew Eugene Hendifar ◽  
Talia Golan ◽  
Milind M. Javle ◽  
...  

271 Background: Mutations in oncogenic KRAS have been widely accepted as the signature genomic alteration (GA) in sporadic PDAC, but therapeutic efforts aimed at targeting constitutively activated KRAS have been disappointing. We examined somatic GAs in KRAS WT PDAC utilizing a CGP platform to identify actionable targets. Methods: DNA was extracted from formalin fixed paraffin embedded (FFPE) PDAC clinical specimens and CGP was performed on hybrid-capture, adaptor ligation based libraries to a mean coverage depth of > 600 unique reads. Alterations in the RAS/ RAF/ MEK pathway genes ( KRAS, NRAS, HRAS, ARF, BRAF, EGFR, MAP2K2, MAP2K1, MAPK1) and DNA Damage Repair (DDR) pathway genes ( BRCA1/2, ATM, ATR, BRIP1, RAD50, RAD51, RAD52, PALB2, CHEK1, CHEK2) were examined. Tumor mutational burden (TMB) was determined on 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on 114 loci. TMB was categorized based on mutations(m)/Mbp of DNA - high (H; > 20), Intermediate (I; 8-20) and low (L; < 8). Results: CGP was performed on 3426 PDAC specimens; 1815 (53%) were male, 390 (11.3%) were KRAS WT. GAs in the RAS/ RAF/ MEK pathway were identified in 90.6% of all cases, while 68 (17.4%) KRAS WT cases had one or more GAs in RAS/ RAF/ MEK pathway genes. DDR pathway GAs were identified in 1405 (41%) cases for a total of 2050 GAs, and 180 (46%) KRAS WT cases for a total of 285 GAs. DDR pathway alterations were common in KRAS WT PDAC compared to KRAS mutated PDAC (p = 0.028). Among the 842 (24.6%) cases with available TMB data, 5 (0.6%), 104 (12.3%) and 733 (87.1%) pts had H, I and L, TMB respectively. Among 88 (22.6%) KRAS WT cases with available TMB data, 2 (2.3%), 12 (13.6%) and 74 (84.1%) pts had H, I and L, TMB, respectively. MSI status was available in 2314 (67.5%) cases, 13 (0.6%) were MSI-high (MSI-H); among the KRAS WT cases, 222 (57%) had MSI status available, 3 (1.3%) were MSI-H. Conclusions: MSI-H status and high TMB are rare in PDAC, regardless of KRAS mutation status. GAs in the DDR pathway are relatively common in PDAC and may serve as predictive biomarkers for platinum chemotherapeutic agents and/or PARP inhibitors. Prospective validation of such predictive gene signatures will improve therapeutic efficacy and minimize toxicities.


BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Michal Marczyk ◽  
Chunxiao Fu ◽  
Rosanna Lau ◽  
Lili Du ◽  
Alexander J. Trevarton ◽  
...  

Abstract Background Utilization of RNA sequencing methods to measure gene expression from archival formalin-fixed paraffin-embedded (FFPE) tumor samples in translational research and clinical trials requires reliable interpretation of the impact of pre-analytical variables on the data obtained, particularly the methods used to preserve samples and to purify RNA. Methods Matched tissue samples from 12 breast cancers were fresh frozen (FF) and preserved in RNAlater or fixed in formalin and processed as FFPE tissue. Total RNA was extracted and purified from FF samples using the Qiagen RNeasy kit, and in duplicate from FFPE tissue sections using three different kits (Norgen, Qiagen and Roche). All RNA samples underwent whole transcriptome RNA sequencing (wtRNAseq) and targeted RNA sequencing for 31 transcripts included in a signature of sensitivity to endocrine therapy. We assessed the effect of RNA extraction kit on the reliability of gene expression levels using linear mixed-effects model analysis, concordance correlation coefficient (CCC) and differential analysis. All protein-coding genes in the wtRNAseq and three gene expression signatures for breast cancer were assessed for concordance. Results Despite variable quality of the RNA extracted from FFPE samples by different kits, all had similar concordance of overall gene expression from wtRNAseq between matched FF and FFPE samples (median CCC 0.63–0.66) and between technical replicates (median expression difference 0.13–0.22). More than half of genes were differentially expressed between FF and FFPE, but with low fold change (median |LFC| 0.31–0.34). Two out of three breast cancer signatures studied were highly robust in all samples using any kit, whereas the third signature was similarly discordant irrespective of the kit used. The targeted RNAseq assay was concordant between FFPE and FF samples using any of the kits (CCC 0.91–0.96). Conclusions The selection of kit to purify RNA from FFPE did not influence the overall quality of results from wtRNAseq, thus variable reproducibility of gene signatures probably relates to the reliability of individual gene selected and possibly to the algorithm. Targeted RNAseq showed promising performance for clinical deployment of quantitative assays in breast cancer from FFPE samples, although numerical scores were not identical to those from wtRNAseq and would require calibration.


PLoS ONE ◽  
2015 ◽  
Vol 10 (7) ◽  
pp. e0127353 ◽  
Author(s):  
Danielle Mercatante Carrick ◽  
Michele G. Mehaffey ◽  
Michael C. Sachs ◽  
Sean Altekruse ◽  
Corinne Camalier ◽  
...  

Author(s):  
Miriam Potrony ◽  
Celia Badenas ◽  
Bénédicte Naerhuyzen ◽  
Paula Aguilera ◽  
Joan Anton Puig-Butille ◽  
...  

AbstractBackground:Methods:DNA was obtained from 144 FFPE samples (62 primary melanoma, 43 sentinel lymph nodes [SLN] and 39 metastasis).Results:Complete sequencing results were obtained from 75% (108/144) of the samples, and at least one gene was sequenced in 89% (128/144) of them.Conclusions:Preserving sufficient tumor area in FFPE blocks is important. It is necessary to keep the FFPE blocks, no matter their age, as they are necessary to decide the best treatment for the melanoma patient.


BioTechniques ◽  
2020 ◽  
Vol 68 (1) ◽  
pp. 48-51 ◽  
Author(s):  
Christopher R McEvoy ◽  
Timothy Semple ◽  
Bhargavi Yellapu ◽  
David Y Choong ◽  
Huiling Xu ◽  
...  

Tumor DNA sequencing results can have important clinical implications. However, its use is often limited by low DNA input, owing to small tumor biopsy size. To help overcome this limitation we have developed a simple improvement to a commonly used next-generation sequencing (NGS) capture-based library preparation method using formalin-fixed paraffin-embedded-derived tumor DNA. By using on-bead PCR for pre-capture library generation we show that library yields are dramatically increased, resulting in decreased sample failure rates. Improved yields allowed for a reduction in PCR cycles, which translated into improved sequencing parameters without affecting variant calling. This methodology should be applicable to any NGS system in which input DNA is a limiting factor.


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