Banelli B et al. (2005) Distinct CpG methylation profiles characterize different clinical groups of neuroblastic tumors. Oncogene [doi: 10.1038/sj.onc.1208722]

In an attempt to discover new prognostic markers in patients with neuroblastic tumors, Banelli et al. have studied the CpG methylation patterns of a panel of genes thought to be involved in cancer development or drug responsiveness. The results of the study indicate that several genes bear distinct epigenetic signatures in different clinical groups of these tumors.

Using methylation-specific polymerase chain reaction or bisulfite restriction enzyme analysis, the investigators looked for distinct methylation profiles within the promoter regions of 11 genes. The tumor samples included 31 malignant neuroblastomas—of which 14 were MYCN-amplified and 17 were single-copy tumors—and 13 benign ganglioneuromas.

Of the 11 genes analyzed, five showed distinct methylation signatures in malignant and benign neuroblastic tumors. These were CASP8, 14.3.3σ, ΔNp73, RASSF1A, and DCR2. For 14.3.3σ, RASSF1A, and an intragenic segment of CASP8, different methylation patterns were found in the MYCN-amplified samples compared with the single-copy tumors, indicating that the methylation profile at these loci is associated with tumor aggressiveness.

The authors propose, therefore, that specific methylation profiles in patients with neuroblastic tumors might help in assessment of the risk of tumor progression. In addition, this approach might help in identifying those patients likely to benefit from particular therapies, as already demonstrated in colorectal cancer patients.