CGH array profiles of melanoma cell lines

Dysfunction in type I interferon (IFN) signaling occurs in patients with stage II or more advanced cancer. After screening the effects of a panel of 12 melanoma cell lines on PBMCs of healthy volunteers of IFNalpha signal pathway, two groups of melanoma cell lines could be identified one with stronger suppression (low pSTAT-1 group) than the other (high pSTAT-1 group). Comparative genomic hybridization (CGH) identified consistent amplification of 12q22-24 as a genomic marker for the immune suppressive melanoma cell lines. This region corresponded to higher transcription of the NOS1 gene located in that region in the low pSTAT1 group and NOS1 expression was identified as causal factor in melanoma induced immune suppression. Twelve melanoma cell lines were analyzed. Genomic DNA of the cell line sample was labeled with Cy5 and reference normal PBMC DNA was labeled with Cy3.