title: In situ mutation detection and visualization of intratumor heterogeneity for cancer research and diagnostics.
abstract: Current assays for somatic mutation analysis are based on extracts from tissue sections that often contain morphologically heterogeneous neoplastic regions with variable contents of normal stromal and inflammatory cells, obscuring the results of the assays. We have developed an RNA-based in situ mutation assay that targets oncogenic mutations in a multiplex fashion that resolves the heterogeneity of the tissue sample. Activating oncogenic mutations are targets for a new generation of cancer drugs. For anti-EGFR therapy prediction, we demonstrate reliable in situ detection of KRAS mutations in codon 12 and 13 in colon and lung cancers in three different types of routinely processed tissue materials. High-throughput screening of KRAS mutation status was successfully performed on a tissue microarray. Moreover, we show how the patterns of expressed mutated and wild-type alleles can be studied in situ in tumors with complex combinations of mutated EGFR, KRAS and TP53. This in situ method holds great promise as a tool to investigate the role of somatic mutations during tumor progression and for prediction of response to targeted therapy.
authors.affiliation: Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Rudbeck Laboratory.
authors.forename: Ida
authors.initials: I
authors.lastname: Grundberg
authors.forename: Sara
authors.initials: S
authors.lastname: Kiflemariam
authors.forename: Marco
authors.initials: M
authors.lastname: Mignardi
authors.forename: Juliana
authors.initials: J
authors.lastname: Imgenberg-Kreuz
authors.forename: Karolina
authors.initials: K
authors.lastname: Edlund
authors.forename: Patrick
authors.initials: P
authors.lastname: Micke
authors.forename: Magnus
authors.initials: M
authors.lastname: Sundström
authors.forename: Tobias
authors.initials: T
authors.lastname: Sjöblom
authors.forename: Johan
authors.initials: J
authors.lastname: Botling
authors.forename: Mats
authors.initials: M
authors.lastname: Nilsson
mesh_terms: D003062:Codon; D003110:Colonic Neoplasms / Q000235:genetics; D004252:DNA Mutational Analysis / Q000379:methods*; D018773:Genes, erbB-1; D016158:Genes, p53; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics; D009369:Neoplasms / Q000235:genetics*; D017354:Point Mutation; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics
chemical_list: D003062:Codon; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins