Meta-analysis of gene expression profiling in amyotrophic lateral sclerosis: A comparison between transgenic mouse models and human patients

Abstract

The exact pathogenic cascade leading to motor neuron degeneration in amyotrophic lateral sclerosis (ALS) is unknown. Gene expression profiles of ALS-affected spinal cord and motor neurons have been well established in mice and man. We provide a meta-analysis of the reported significant gene lists of gene expression studies in ALS, and compare results between mouse models and human post mortem tissue. In total, 12 articles met inclusion criteria. Twenty-nine genes were found to be differentially expressed at least twice in studies using human post mortem tissue, enriched for the functions ‘immune response’, ‘apoptosis’ and ‘protein metabolism’. In mouse studies, 86 genes were reported at least two times and were enriched for ‘immune response’, ‘lysosome’, ‘metal ion binding’ and ‘mitochondrion’. Next, all differentially expressed genes from the mouse studies were translated to human homologous genes. Seventy-four differentially expressed genes in mouse tissue were also found to be differentially expressed in human tissue. In conclusion, evidence was found for shared dysfunction in protein turnover in the ubiquitin-proteasome system. Differential expression of Cathepsin B and D, GFAP and SERPINA3 was repeatedly found to be significant in both the mouse model and ALS patients.

Key words::

• RNA
• transgenic animals
• SOD1
• ubiquintin

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This study was supported by the European Community’s Health Seventh Framework Programme. LHB received travel grants and consultancy fees from Baxter International, Prinses Beatrix Fonds and Biogen Idec; serves on the editorial board of Amyotrophic Lateral Sclerosis; and receives research support from the Netherlands Organization for Health Research and Development, Prinses Beatrix Fonds, Netherlands ALS Foundation, VSB Fonds and Adessium Foundation.