Changes in WT1 splicing are associated with a specific gene expression profile in Wilms' tumour.
Wilms' tumour (WT) or nephroblastoma is the most frequent kidney cancer in children. In a previous study, we reported alterations to WT1 transcription in 90% of WT tested, with decreased exon 5 +/- isoform ratio being the most frequent alteration (56% of WT). We now report an approach based on cDNA profiling of tumour pools to identify genes likely to be dysregulated in association with a decreased WT1 exon 5 +/- ratio. We compared the expression profiles of pools of tumours classified according to whether this isoform imbalance was present (five tumours) or not (four tumours), using Atlas Cancer cDNA expression arrays. Fourteen of 588 genes tested displayed specific up-regulation (CCND2, PCNA, N-MYC, E2F3, TOP2A, PAK1, DCC and PCDH2) or down-regulation (VEGF, IGFBP5, TIMP3, ARHB, C-FOS and CD9) in the pool of tumours with decreased exon 5 +/- ratio. These results were validated by RT-PCR analysis of four genes (CCND2, PCNA, VEGF and IGFBP5). We extended the analysis of VEGF expression to 51 tumours by real-time RT-PCR and ascertained differential expression of this gene associated with WT1 expression pattern. Moreover, our results suggest that the VEGF expression level may be of prognosis relevance for relapsed patients.
Baudry
Dominique
D
INSERM U383, Hôpital Necker-Enfants Malades, Université René Descartes, 75743 Paris Cedex 15, France.
Faussillon
Marine
M
Cabanis
Marie-Odile
MO
Rigolet
Muriel
M
Zucker
Jean-Michel
JM
Patte
Catherine
C
Sarnacki
Sabine
S
Boccon-Gibod
Liliane
L
Junien
Claudine
C
Jeanpierre
Cécile
C
D017398:Alternative Splicing; D017931:DNA Primers / Q000737:chemistry; D015536:Down-Regulation; D005091:Exons; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D007668:Kidney / Q000378:metabolism; D007680:Kidney Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011379:Prognosis; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation; D025721:WT1 Proteins / Q000235:genetics* / Q000378:metabolism; D009396:Wilms Tumor / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
D017931:DNA Primers; D009363:Neoplasm Proteins; D020033:Protein Isoforms; D025721:WT1 Proteins