FCGR3A/2A polymorphisms and diffuse large B‐cell lymphoma outcome treated with immunochemotherapy: a meta‐analysis on 1134 patients from two prospective cohorts
Abstract Background: Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy is standard of care for patients with newly diagnosed DLBCL. A majority of patients respond to R-CHOP, however ∼9% will have primary refractory disease and outcomes in these patients are extremely poor. While there is some knowledge of the pharmacogenomic (PGx) determinants of individual agents within R-CHOP, little is known about the PGx determinants of combination therapy. Our study aims to elucidate germline PGx determinants of drug bioavailability and undesirable side chain reactions in DLBCL patients treated with R-CHOP having potential to influence refractory disease. Methods: Newly diagnosed, DLBCL patients treated with R-CHOP between 2002 and 2012 with germline DNA and genotyping data were selected from the Molecular Epidemiology Resource within the Iowa/Mayo Lymphoma SPORE. Refractory disease was defined as either i) a best response of stable or progressive disease or ii) progressive disease by the end of the planned number of cycles of R-CHOP. PGx candidates within known pharmacokinetics and pharmacodynamics (PD) pathways for 11 genes (1,040 single nucleotide polymorphisms (SNPs)) were selected for study (CPT 2012;92(4):414-7). Odds ratios (ORs) and 95% confidence intervals (CI) were used to estimate the association of SNPs with refractory disease, controlling for age, gender, and age-adjusted International Prognostic Index. Results: The median age at diagnosis of 424 of DLBCL patients treated with R-CHOP was 62 years (range 18-92); 45.7% were female; and 58.4% had Ann Arbor Stage III-IV. By the end of initial therapy 40 patients had primary refractory disease. Of the 1,040 SNPs evaluated, 120 (12%) were significantly associated with refractory disease at the 5% significance threshold suggesting novel associations with drug metabolism. The top SNP from each PGx candidate gene are shown in Table, with ALDH5A1 and CYP2B6 showing the most significant associations. Conclusions: While needing replication, we identified associations within two PGx candidate genes that are potentially functionally related to cyclophosphamide PD: alleles within CYP2B6 may have relevance in R-CHOP outcomes due to potential competition with other drug metabolizing enzymes shared with prednisone and vincristine biotransformation in the liver, and alleles withinALDH5A1 may impact a deactivating side chain reaction in B lymphocytes. Table: R-CHOP PGx candidates with known side chain reactionsPGx candidaten SNPsTop SNPChrOR* (95% CI)P-valueMAFABCB1365rs3480093571.86 (1.14 – 3.04)1.32E-020.29ADH1A32rs122996841.66 (0.60 - 4.53)3.27E-010.038ALDH3A116rs2228100171.26 (0.71 - 2.22)4.28E-010.24ALDH5A1192rs946103466.30 (2.43 - 16.4)1.55E-040.030CBR110rs2835266212.10 (0.90 - 4.89)8.76E-020.052CBR356rs45527331212.12 (0.91 - 4.98)8.29E-020.050CYP2B6107rs1038376192.38 (1.44 - 3.94)7.74E-040.27CYP3A421rs2898858372.32 (0.80 - 6.78)1.23E-010.028CYP3A531rs778032871.69 (0.68 - 4.16)2.57E-010.054SLC22A16193rs11217403561.80 (1.06 - 3.03)2.78E-020.21SOD116rs1041740211.35 (0.83 - 2.19)2.26E-010.32Chr=chromosome, MAF=minor allele frequency, *Adjusted for age, sex, and age-adjusted International Prognostic Index Citation Format: Matthew K. Breitenstein, Susan L. Slager, Anne J. Novak, Matthew J. Maurer, Carrie A. Thompson, Umar Farooq, Brian K. Link, Thomas M. Habermann, Curtis L. Olswold, Andrew L. Feldman, Grzegorz S. Nowakowski, Stephen M. Ansell, Thomas E. Witzig, Richard M. Weinshilboum, Liewei Wang, James R. Cerhan. Pharmacogenomic of refractory response to R-CHOP therapy in diffuse large B-cell lymphoma (DLBCL) patients. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B143.
First report of MYD88L265P somatic mutation in IgM-associated light-chain amyloidosis
Abstract P6-07-03: An exhaustive algorithm for detecting copy number aberrations and large structural variants in whole-genome mate-pair sequencing data
Cancer Research | May 4, 2015 | Volume: 75 | Issue: 9_Supplement | Pages: P6-07-03-P6-07-03
Abstract Objectives and Rationale: Structural variants (SV) including large copy number aberrations (CNV), translocations, inversions, and large insertions and deletions (INDEL) play a critical role in tumorigenesis and progression. In fact, we now know that tumors can be categorized according to the size of mutations harbored. In several cancers, including ovarian and breast cancer, the large structural mutations, rather than single site mutations, play a dominate role in tumor etiology. Therefore, it's critical to implement reliable algorithm for the detection of structural variants in DNA sequencing data. Mate-pair sequencing is a protocol specifically implemented for detection of the whole-genome level structural variants. It requires less sequencing depth therefor is cost effective, and enables the detection of CNVs, translocations, and inversions simultaneously. However, so far there has been no reliable bioinformatics pipeline for the analyses of the mate-pair sequencing data. Methods: Our novel algorithm, the SnowShoes-SV, is an exhaustive search algorithm designed specifically for mate-pair DNA sequencing data analyses. It calls the SVs based on disconcordant read pairs. The false SVs are filtered according to the following criteria: (i) the number of the supporting read pairs; (ii) the lack of reads from control data that implicate SV at the same region; (iii) the mappability and uniqueness of the region based on data from the ENCODE project; (iv) consistencies of the mapping orientations of the supporting read pairs; (v) the similar sizes between sequencing library and the two end read clusters. Results: Using a set of samples previously genotyped by aCGH, the SnowShoes-SV successfully detected all known CNVs and other SVs. It also identified copy number neutral translocations and inversions previously not identified by aCGH. In addition, the algorithm nominated novel SVs which are to be validated by PCR. Conclusions: SnowShoes-SV is a highly sensitive and specific algorithm for SV detection from the mate-pair DNA sequencing data. Citation Format: Yan W Asmann, Chen Wang, Brian M Necela, Xianfeng Chen, Jean-Pierre A Kocher, Matthew J Maurer, Thomas M Habermann, Susan L Slager, Andrew L Feldman, Anne J Novak, James R Cerhan, Edith A Perez, E Aubrey Thompson. An exhaustive algorithm for detecting copy number aberrations and large structural variants in whole-genome mate-pair sequencing data [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-07-03.
Targeted inhibition of the deubiquitinating enzymes, USP14 and UCHL5, induces proteotoxic stress and apoptosis in Waldenström macroglobulinaemia tumour cells
British Journal of Haematology | February 17, 2015 | Volume: 169 | Issue: 3 | Pages: 377-390
SummaryDeubiquitinase enzymes (DUBs) of the proteasomal 19S regulatory particle are emerging as important therapeutic targets in several malignancies. Here we demonstrate that inhibition of two proteasome‐associated DUBs (USP14 and UCHL5) with the small molecule DUB inhibitor b‐AP15, results in apoptosis of human Waldenström macroglobulinaemia (WM) cell lines and primary patient‐derived WM tumour cells. Importantly, b‐AP15 produced proteotoxic stress and apoptosis in WM cells that have acquired resistance to the proteasome inhibitor bortezomib. In silico modelling identified protein residues that were critical for the binding of b‐AP15 with USP14 or UCHL5 and proteasome enzyme activity assays confirmed that b‐AP15 does not affect the proteolytic capabilities of the 20S proteasome β‐subunits. In vitro toxicity from b‐AP15 appeared to result from a build‐up of ubiquitinated proteins and activation of the endoplasmic reticulum stress response in WM cells, an effect that also disrupted the mitochondria. Focused transcriptome profiling of b‐AP15‐treated WM cells revealed modulation of several genes regulating cell stress and NF‐κB signalling, the latter whose protein translocation and downstream target activation was reduced by b‐AP15 in vitro. This is the first report to define the effects and underlying mechanisms associated with inhibition of USP14 and UCHL5 DUB activity in WM tumour cells.
BCL2 mutations are associated with increased risk of transformation and shortened survival in follicular lymphoma
Key Points BCL2 mutations in FL correlate with activation-induced cytidine deaminase expression and frequently alter the amino acid sequence of the protein. Mutations in the BCL2 coding sequence at diagnosis are associated with shortened time to transformation and earlier death due to lymphoma.
Elevated serum levels of IL-2R, IL-1RA, and CXCL9 are associated with a poor prognosis in follicular lymphoma
Key Points Elevated IL-2R, IL-1RA, and CXCL9 are associated with shorter event-free survival in newly diagnosed FL, treated with chemoimmunotherapy. Increased serum IL-12 and IL-1RA is associated with shorter event-free survival in patients who were observed or treated with rituximab alone.
RVboost: RNA-seq variants prioritization using a boosting method
Abstract Motivation: RNA-seq has become the method of choice to quantify genes and exons, discover novel transcripts and detect fusion genes. However, reliable variant identification from RNA-seq data remains challenging because of the complexities of the transcriptome, the challenges of accurately mapping exon boundary spanning reads and the bias introduced during the sequencing library preparation. Method: We developed RVboost, a novel method specific for RNA variant prioritization. RVboost uses several attributes unique in the process of RNA library preparation, sequencing and RNA-seq data analyses. It uses a boosting method to train a model of ‘good quality’ variants using common variants from HapMap, and prioritizes and calls the RNA variants based on the trained model. We packaged RVboost in a comprehensive workflow, which integrates tools of variant calling, annotation and filtering. Results: RVboost consistently outperforms the variant quality score recalibration from the Genome Analysis Tool Kit and the RNA-seq variant-calling pipeline SNPiR in 12 RNA-seq samples using ground-truth variants from paired exome sequencing data. Several RNA-seq–specific attributes were identified as critical to differentiate true and false variants, including the distance of the variant positions to exon boundaries, and the percent of the reads supporting the variant in the first six base pairs. The latter identifies false variants introduced by the random hexamer priming during the library construction. Availability and implementation: The RVboost package is implemented to readily run in Mac or Linux environments. The software and user manual are available at http://bioinformaticstools.mayo.edu/research/rvboost/. Supplementary information: Supplementary data are available at Bioinformatics online.
PatternCNV: a versatile tool for detecting copy number changes from exome sequencing data
Abstract Motivation: Exome sequencing (exome-seq) data, which are typically used for calling exonic mutations, have also been utilized in detecting DNA copy number variations (CNVs). Despite the existence of several CNV detection tools, there is still a great need for a sensitive and an accurate CNV-calling algorithm with built-in QC steps, and does not require a paired reference for each sample. Results: We developed a novel method named PatternCNV, which (i) accounts for the read coverage variations between exons while leveraging the consistencies of this variability across different samples; (ii) reduces alignment BAM files to WIG format and therefore greatly accelerates computation; (iii) incorporates multiple QC measures designed to identify outlier samples and batch effects; and (iv) provides a variety of visualization options including chromosome, gene and exon-level views of CNVs, along with a tabular summarization of the exon-level CNVs. Compared with other CNV-calling algorithms using data from a lymphoma exome-seq study, PatternCNV has higher sensitivity and specificity. Availability and implementation: The software for PatternCNV is implemented using Perl and R, and can be used in Mac or Linux environments. Software and user manual are available at http://bioinformaticstools.mayo.edu/research/patterncnv/ , and R package at https://github.com/topsoil/patternCNV/ . Contact: Asmann.Yan@mayo.edu Supplementary information: Supplementary data are available at Bioinformatics online.