Copy Number Alterations with Prognostic Potential in Clear Cell Renal Cell Carcinoma.

OBJECTIVES: To detect chromosomal aberrations in a genome-wide manner with potential value for prognosis in groups of patients with different histopathological grading in clear cell renal carcinoma (ccRCC).

MATERIAL AND METHODS: We performed a copy number alteration analysis using the Affymetrix platform and SNP 6.0 mapping arrays with samples from 48 ccRCC-patients. The data analysis was done using 3 different Software Platforms: Affymetrix Genotyping Console (version 4.1.3.840) and 2 open-source packages for validation: PennCNV and PICNIC.

RESULTS: Consistent changes were found to divide the tumors into 4 groups: first group showed typical losses on 3p, second group losses on 3p plus gains on 5q, third group gains on chromosome 7 plus losses on chromosome 8; fourth group did not show any major changes. We selected the affected genes with the highest consistency and identified 13 different genes mapping in the SNP 6.0 results and Kyoto Encyclopedia of Genes and Genomes. Remarkable for further consideration were the phosphatidylinositol 3-kinase pathway, BRAF, MET, EGLN1; growth factors, for example, HGF, PGF and TGFB2.

CONCLUSION: A multimodal approach with a well-defined workflow for detecting genomic aberrations by using array technologies and comparing the findings with different comprehensive databases may provide insights into functional tumor processes and help to identify potential new targets for more individualized future treatment.