Biomarkers in Tumor Tissue Samples From Young Patients With Very Low Risk Wilms Tumors

OBJECTIVES:

• To validate the utility of CUGBP2, HMGA2, and MEIS2 mRNA expression and 11p15 methylation to define a population of pediatric patients with very low risk Wilms tumor (VLRWT) that have virtually no risk of relapse.
• To validate the utility of WT-1 mutation and 11p15 loss of heterozygosity analysis to determine a population of VLRWT that have a higher risk of relapse when not treated with chemotherapy.
• To validate the utility of NFYA, STRA6, TOB2, PDCD4, and SP3 mRNA expression to predict relapse in VLRWT.
• To investigate the feasibility of broadening the definition of VLRWT through analysis of stage I and II epithelial differentiated tumors registered on clinical trial COG-Q9401 (NWTS-5) for CUGBP2, HMGA2, MEIS2, and 11p15 methylation.

OUTLINE: Previously banked tumor tissue samples are analyzed for mRNA expression of CUGBP2, HMGA2, and MEIS2 via reverse-transcriptase (RT)-PCR and are classified as loss of heterozygosity (LOH), loss of imprinting, or neither via 11p15 analysis. Samples are also analyzed for WT-1 mutation via quantitative PCR and 11p LOH using 11p15 methylation analysis and expression of NFYA, STRA6, TOB2, PDCD4, and SP3 via quantitative RT-PCR