Entropy measures quantify global splicing disorders in cancer

Autor: Samuel Granjeaud, Denis Puthier, William Ritchie, Daniel Gautheret
Přispěvatelé: Technologies avancées pour le génôme et la clinique (TAGC), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de génétique et microbiologie [Orsay] (IGM), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), This work was supported in part by European Commission grant LSHG-CT-2003-503329 (The Alternative Transcript Diversity Consortium) and Institut National du Cancer grant PL0079., Beaunay, Stephanie
Jazyk: angličtina
Rok vydání: 2008
Předmět:
MESH: Neoplasm Proteins
Polyadenylation
Entropy
MESH: Gene Targeting
MESH: Variation (Genetics)
0302 clinical medicine
Neoplasms
Gene expression
MESH: Neoplasms
MESH: Models
Genetic

Biology (General)
Genetics
Regulation of gene expression
0303 health sciences
Ecology
MESH: Alternative Splicing
MESH: Genetic Predisposition to Disease
Genetics and Genomics/Gene Expression
MESH: Gene Expression Regulation
Neoplastic

MESH: Entropy
Neoplasm Proteins
3. Good health
Gene Expression Regulation
Neoplastic

Computational Theory and Mathematics
030220 oncology & carcinogenesis
Modeling and Simulation
Gene Targeting
RNA splicing
Research Article
MESH: Mutation
QH301-705.5
Computational biology
Biology
03 medical and health sciences
Cellular and Molecular Neuroscience
MESH: Computer Simulation
Protein splicing
MESH: Protein Splicing
Biomarkers
Tumor

[SDV.BBM] Life Sciences [q-bio]/Biochemistry
Molecular Biology

Humans
Protein Splicing
Computational Biology/Alternative Splicing
Computer Simulation
Genetic Predisposition to Disease
splice
[SDV.BBM]Life Sciences [q-bio]/Biochemistry
Molecular Biology

Molecular Biology
Gene
Ecology
Evolution
Behavior and Systematics

030304 developmental biology
Models
Statistical

MESH: Humans
Models
Genetic

Alternative splicing
Genetic Variation
Alternative Splicing
Mutation
MESH: Tumor Markers
Biological

MESH: Models
Statistical
Zdroj: PLoS Computational Biology
PLoS Computational Biology, Public Library of Science, 2008, 4 (3), pp.e1000011. ⟨10.1371/journal.pcbi.1000011⟩
PLoS Computational Biology, Vol 4, Iss 3, p e1000011 (2008)
PLoS Computational Biology, 2008, 4 (3), pp.e1000011. ⟨10.1371/journal.pcbi.1000011⟩
ISSN: 1553-734X
1553-7358
DOI: 10.1371/journal.pcbi.1000011⟩
Popis: Most mammalian genes are able to express several splice variants in a phenomenon known as alternative splicing. Serious alterations of alternative splicing occur in cancer tissues, leading to expression of multiple aberrant splice forms. Most studies of alternative splicing defects have focused on the identification of cancer-specific splice variants as potential therapeutic targets. Here, we examine instead the bulk of non-specific transcript isoforms and analyze their level of disorder using a measure of uncertainty called Shannon's entropy. We compare isoform expression entropy in normal and cancer tissues from the same anatomical site for different classes of transcript variations: alternative splicing, polyadenylation, and transcription initiation. Whereas alternative initiation and polyadenylation show no significant gain or loss of entropy between normal and cancer tissues, alternative splicing shows highly significant entropy gains for 13 of the 27 cancers studied. This entropy gain is characterized by a flattening in the expression profile of normal isoforms and is correlated to the level of estimated cellular proliferation in the cancer tissue. Interestingly, the genes that present the highest entropy gain are enriched in splicing factors. We provide here the first quantitative estimate of splicing disruption in cancer. The expression of normal splice variants is widely and significantly disrupted in at least half of the cancers studied. We postulate that such splicing disorders may develop in part from splicing alteration in key splice factors, which in turn significantly impact multiple target genes.
Author Summary RNA splicing is the process by which gene products are pieced together to form a mature messenger RNA (mRNA). In normal cells, RNA splicing is a tightly controlled process that leads to production of a well-defined set of mRNAs. Cancer cells, however, often produce aberrant, mis-spliced mRNAs. Such disorders have not been quantified to date. To this end, we use a well-known measure of disorder called Shannon's entropy. We show that overall splicing disorders are highly significant in many cancers, and that the extent of disorder may be correlated to the level of cell proliferation in each tumor. Surprisingly, genes that control the splicing mechanism are unusually frequent among genes affected by splicing disorders. This suggests that cancer cells may withstand harmful chain reactions in which splicing defects in key regulatory genes would in turn cause extensive splicing damage. As mis-spliced mRNAs are widely studied for cancer diagnosis, awareness of these global disorders is important to distinguish reliable cancer markers from background noise.
Databáze: OpenAIRE