Medler et al. reported that urokinase-expressing macrophages regulated C3-independent C5a release during tumor promotion in K14-HPV16 transgenic mice; this, in turn, regulated the protumorigenic properties of macrophages (high in C5aR1 expression), including the inhibition of the cytotoxic activity of CD8+ T cells [72]. Here, C5AR1 is linked to neoplasm.