Gene Expression Patterns in a Congenital Neurocristic Hamartoma With Multiple Proliferative Nodules.

Cutaneous neurocristic hamartoma (CNH) is a rare lesion composed of neural crest derivatives, thought to arise from aberrant migration and differentiation of neural crest cells. Recognition of CNH may be difficult, as they may resemble giant congenital nevus, and development of proliferative nodules (PNs) may raise concern for malignant transformation. Assessment of gene expression in CNH and PNs derived from CNH may offer insight into pathogenesis and suggest clinically useful biomarkers to identify these entities. This study investigates gene expression patterns in a congenital CNH and three separate PNs derived from that CNH with giant congenital nevus and malignant melanoma as comparator groups. Comparison of PN to CNH demonstrates downregulation of WIF1, which encodes as a tumor suppressor, and loss of WIF1 expression might explain the progression from CNH to PN. Comparison of gene expression in PN and CNH with giant congenital nevus and malignant melanoma shows relative overexpression of IGF2 and H19 in CNH and PN, suggesting that abnormal imprinting and IGF2 overexpression may have integral functions in the foundation of CNH.