This tab shows an overview of the selected study/paper [more details]
Reference

Non-invasive analysis of acquired resistance to cancer therapy by sequencing of plasma DNA.

Paper Id
COSP31592
Authors
Murtaza M,Dawson SJ,Tsui DW,Gale D,Forshew T,Piskorz AM,Parkinson C,Chin SF,Kingsbury Z,Wong AS,Marass F,Humphray S,Hadfield J,Bentley D,Chin TM,Brenton JD,Caldas C and Rosenfeld N
Affiliation
Cancer Research UK Cambridge Institute and University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
Journal
Nature 2013;497(7447):108-12
ISSN:1476-4687
PUBMED:23563269
Abstract
Cancers acquire resistance to systemic treatment as a result of clonal evolution and selection. Repeat biopsies to study genomic evolution as a result of therapy are difficult, invasive and may be confounded by intra-tumour heterogeneity. Recent studies have shown that genomic alterations in solid cancers can be characterized by massively parallel sequencing of circulating cell-free tumour DNA released from cancer cells into plasma, representing a non-invasive liquid biopsy. Here we report sequencing of cancer exomes in serial plasma samples to track genomic evolution of metastatic cancers in response to therapy. Six patients with advanced breast, ovarian and lung cancers were followed over 1-2 years. For each case, exome sequencing was performed on 2-5 plasma samples (19 in total) spanning multiple courses of treatment, at selected time points when the allele fraction of tumour mutations in plasma was high, allowing improved sensitivity. For two cases, synchronous biopsies were also analysed, confirming genome-wide representation of the tumour genome in plasma. Quantification of allele fractions in plasma identified increased representation of mutant alleles in association with emergence of therapy resistance. These included an activating mutation in PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) following treatment with paclitaxel; a truncating mutation in RB1 (retinoblastoma 1) following treatment with cisplatin; a truncating mutation in MED1 (mediator complex subunit 1) following treatment with tamoxifen and trastuzumab, and following subsequent treatment with lapatinib, a splicing mutation in GAS6 (growth arrest-specific 6) in the same patient; and a resistance-conferring mutation in EGFR (epidermal growth factor receptor; T790M) following treatment with gefitinib. These results establish proof of principle that exome-wide analysis of circulating tumour DNA could complement current invasive biopsy approaches to identify mutations associated with acquired drug resistance in advanced cancers. Serial analysis of cancer genomes in plasma constitutes a new paradigm for the study of clonal evolution in human cancers.
Paper Status
Curated
Genes Analysed
428
Mutated Samples
6
Total No. of Samples
6
This tab shows genes with mutations in the selected study/paper [more details]
Genes Samples CDS Mutation AA Mutation
This tab shows genes without mutations in the selected study/paper [more details]
Non-Mutant Genes Gene Id (COSG)
This tab shows samples without mutations in the selected study/paper [more details]
Non-Mutant Samples Sample Id (COSS)
This tab shows mutated samples in the selected study/paper [more details]
Sample Name Mutation Count
This tab shows non coding variant in the selected study/paper [more details]
Sample ID Sample Name ID NCV Annotation Zygosity Chromosome Genome start Genome stop Genome version Strand WT seq Mut seq
This tab shows the gene expression and copy number variation data for this study. [more details]

Table Information

Hide

The table currently shows only high value (numeric) copy number data. Copy number segments are excluded if the total copy number and minor allele values are unknown.

Click here to include all copy number data. For more detailed information about copy number data and gain/loss definitions click here.

Sample Gene Expression Expr Level (Z-Score)

Over Expressed; Z-Score > 2.0

Under Expressed; Z-Score < -2.0

Normal; Z-Score within the range -2.0 to 2.0

CN Type Minor Allele Copy Number CN Segment Posn. Average Ploidy

1. N/A represents cases where the average ploidy value is not available( mostly ICGC samples). For some TCGA samples where the minor allele information is not available the average ploidy value could not be calculated.

2. For TCGA samples, the ASCAT algorithm was used to calculate the average ploidy.

3. For CGP samples, the PICNIC algorithm was used to calculate the average ploidy.

CNV
This tab shows a summary table with counts (number of samples) for CNV gain/loss and under/over expression for all genes. [more details]

The results shown in this table are derived from all copy number data. This includes non-numeric data with descriptive definitions of gain/loss.

  Copy Number Expression
Gene Gain Loss Tested Over Under Tested
This tab shows the fusion mutations observed in this sample [more details]
Gene Sample Name Id Sample(COSS) CDS Mutation Somatic status Zygosity Validated Type