Figure 1. Devising a list of genes indicative of specific immune cells infiltrating melanoma.

From the initial gene list, genes found to be highly expressed in melanoma cell lines (in-house data) were removed, resulting in 458 genes retained representing 30 distinct immune cell types (Subset 1). In a second step, cell subsets where more than 90% of genes were lost in the previous step were removed, resulting in Subset 2. In the third step of filtering, all genes negatively correlating with the majority of the genes within each cell subset were removed, and thus the final number of genes was 376 representing 27 immune cell scores (Subset 3). Next, those genes were used to calculate a score for each immune cell, and these were used for consensus clustering of the tumors in immunologically different groups.