Endogenous Perturbation Analysis of Cancer
Sven Nelander, Wallenberg laboratory / Sahlgrenska-CMR University of Gothenburg
- nsdag, 2010 oktober 06
Endogenous Perturbation Analysis of Cancer Sven Nelander, - - PowerPoint PPT Presentation
Endogenous Perturbation Analysis of Cancer Sven Nelander, Wallenberg laboratory / Sahlgrenska-CMR University of Gothenburg onsdag, 2010 oktober 06 Previous work at MSKCC: the CoPIA method Fraction of newly FDA-approved cancer drugs that
Sven Nelander, Wallenberg laboratory / Sahlgrenska-CMR University of Gothenburg
Nelander et al, MSB 2008
Fraction of newly FDA-approved cancer drugs that target signalling
DNA
RNA
Genetic profile ~10s of mutations affecting protein seq ~100s of copy-number altered genes Epigenetic profile ~100s of hypermethylated promoters
Transcriptional profile ~100s-1000s altered message RNA levels ~10s-100s altered micro-RNA levels
samples
(Representative numbers for glioblastoma shown)
profiles
sequencing
Agilent Affymetrix Illumina Solexa etc..
Genes Tumors
White: unchanged, Red: gain/upregulation, Blue: loss/downregulation
Data generated and prepared by the Cancer Genome Atlas Consortium (MSKCC, Broad and other centers)
Perturbation-response pairs (e.g. siRNA → mRNA) Inherited genotype → phenotype pairs (e.g. CNV → mRNA) Acquired genotype → phenotype pairs (CNA → mRNA)
Intuitive model State space model Linear steady state equation
Solve for A or G using the Lasso penalty (Tibshirani 1995) and cyclic coordinate descent method (matlab/mex implemnentation, c.a. 30 sec for 10000 genes, 200 patients). For convex methods and gene methods, see e.g. early work by Yeung/Collins 2001, recent work by Boyd et al
n x n n x p n x p n x p
n x n n x p
n x p
n x p n x n n x n
‘System’ ‘Transfer’
Transfer matrix G System matrix A
(identified in at least 200/1000 bootstrap runs on 10672 genes)
GO analysis: GO:0007267 cell signaling (p=10-12), GO:0007399 nervous system development (p=10-10) What about the A matrix?: dominated by inflammatory genes and and blood cell markers
5 8 2 2
Numbers in boxes: # targets in each category
Can the geometry of G be used for survival predictions?
CNA perturbations mRNA responses
projection of mRNA profiles onto the main axis of G gives a ‘signal amplification score’ Blue group: score<0, Red group: score >0
perturbations and mRNA responses
and a more relevant selection of genes (GO, inspection, survival)
cancer genome data.
protein NDN).
Barncancerfonden, Assar Gabrielssons stiftelse, EMBO, Kungliga vetenskapsakademin, Sahlgrenska akademin