Dados do Trabalho

Título

Evaluation of the Gene Expression Levels of the WNT Pathway in Brain Tissue of Patients with Refractory Epilepsy and Focal Cortical Dysplasia

Introdução

Focal cortical dysplasia (FCD) is a frequent form of cortical development malformation, associated with a significant number of partial epilepsies refractory to drug treatment. Its etiology is still unknown and is probably related to clonal somatic mutations that affect similar signaling pathways. The WNT is a signaling pathway that controls the embryonic development involved in cell differentiation, migration and apoptosis and it is presumed that it is associated with the etiology of FCD. Therefore, it’s of great importance to better understand these factors in order to be able to advance in the compression of FCD.

Objetivo

To analyze possible changes in expression and methylation levels of genes related to the WNT pathway of patients with FCD compared with brain tissue from control patients.

Método

This study was approved by the CEP PUCRS. Dysplastic brain tissue was collected from 10 patients with FCD during surgical resection for treatment of refractory epilepsy and from 4 control participants with lobe temporal epilepsy during hippocampectomy surgery. RNA and DNA was extracted using column kit and cDNA synthesis was performed and quantified. The molecular analysis (super array) of WNT signaling pathways was performed with the TaqMan™ Array Human WNT Pathway with 92 different genes. Genes that showed a significant difference in relative expression had their expression analyzed using the polymerase chain reaction (PCR) technique. Statistical analysis was performed by heatmap analysis and Student's t-test.

Resultados

We observed that the following genes related to the WNT signaling pathway had a significantly different expression in the samples from FCD patients and control group: AXIN1, AXIN2, BCL9, CTBP1, DKK1, DVL1, FGF4, FOSL1, FZD1, FZD2, FZD4, FZD5, FZD7, FZD9, KREMEN1, LRP5, MMP7, NKD1, PITX2, PPARD, PYGO1, SFRP4, SOX17, VANGL2, WISP1. The DNA will be used for sequencing and methylation analyses.

Conclusão

The study showed different expressions in 25 genes of the WNT signaling pathway between patients with FCD and healthy patients, which reiterates the possibility that this pathway is involved in the pathogenesis of FCD. Hence, the study deepens the knowledge of the molecular changes associated with FCD.

Palavras-chave

Focal cortical dysplasia; gene expression; WNT signaling pathway.