TLR2 and melanoma: Since we did not observe changes in IL-6 mRNA levels we decided to analyze the TLR2 expression levels on the different malignant melanoma cell lines used and found that, compared to monocyte-derived myeloid dendritic cells (Mo-mDCs), the malignant melanoma cell lines (A375, Mewo and HTB63) lacked TLR2 expression (Additional file 1: Figure S3 B).