title: Genome-wide expression patterns of invasion front, inner tumor mass and surrounding normal epithelium of colorectal tumors.
abstract: Colorectal tumors have characteristic genome-wide expression patterns that allow their distinction from normal colon epithelia and facilitate clinical prognosis. The expression heterogeneity within a primary colorectal tumor has not been studied on a genome scale yet. Here we investigated three compartments of colorectal tumors, the invasion front, the inner tumor mass, and surrounding normal epithelial tissue by microdissection and microarray-based expression profiling. In both tumor compartments many genes were differentially expressed when compared to normal epithelium. The sets of significantly deregulated genes in both compartments overlapped to a large extent and revealed various interesting known and novel pathways that could have contributed to tumorigenesis. Cells from the invasion front and inner tumor mass, however, did not show significant differences in their expression profile, neither on the single gene level nor on the pathway level. Instead, gene expression differences between individuals are more pronounced as all patient-matched tumor samples clustered in close proximity to each other. With respect to invasion front and inner tumor mass we conclude that the specific tumor cell micro-environment does not have a strong influence on expression patterns: largely similar genome-wide expression programs operate in the invasion front and interior compartment of a colorectal tumor.
authors: Max Planck Institute for Molecular Genetics, Department of Computational Molecular Biology, Berlin, Germany. eike.staub@nucleolus.net
authors: Eike
authors: E
authors: Staub
authors: Joern
authors: J
authors: Groene
authors: Maya
authors: M
authors: Heinze
authors: Detlev
authors: D
authors: Mennerich
authors: Stefan
authors: S
authors: Roepcke
authors: Irina
authors: I
authors: Klaman
authors: Bernd
authors: B
authors: Hinzmann
authors: Esmeralda
authors: E
authors: Castanos-Velez
authors: Christian
authors: C
authors: Pilarsky
authors: Benno
authors: B
authors: Mann
authors: Thomas
authors: T
authors: Brümmendorf
authors: Birgit
authors: B
authors: Weber
authors: Heinz-Johannes
authors: HJ
authors: Buhr
authors: André
authors: A
authors: Rosenthal
mesh_terms: D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009361:Neoplasm Invasiveness / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis