To assess the involvement of NF-κB in the bcl-2-mediated M2 macrophage polarization, we impaired the nuclear translocation of p65 by transfecting bcl-2 overexpressing melanoma cells with IKBSR, the mutated form of IKBα acting as NF-κB super repressor (online supplementary figure S4B, S4C). Here, NFKB1 is linked to melanoma.