Aberrant DNA methylation silences the novel heat shock protein H11 in melanoma but not benign melanocytic lesions.

BACKGROUND

The heat shock protein H11 is silenced in melanoma cell lines, where its forced expression by demethylation with Aza-C triggers apoptosis.

OBJECTIVE

To examine whether H11 is silenced by aberrant DNA methylation in melanoma as compared to nevi and normal skin tissues.

METHODS

Cell suspensions from benign intradermal nevi, atypical nevi and malignant melanoma tissues were used in reverse-transcriptase PCR and methylation-specific PCR. Paraffin-embedded tissues were stained with H11 antibody.

RESULTS

H11 is methylated in 60-75% of melanoma and atypical nevi, but not in normal skin or most benign nevi. Methylation is inversely correlated with H11 expression.

CONCLUSION

The heat shock protein H11 is silenced by aberrant DNA methylation in melanoma, but not benign melanocytic lesions or normal skin melanocytes. The data suggest that H11 is a promising target for the molecular therapy of melanoma.