In in vitro experiments, an Env protein coded by the HERV-K(HML-2) consensus sequences as well as by several HERV-K(HML-2) elements can interact with a cellular signaling pathway often involved in cancers (Lemaitre et al., 2017), suggesting a potential pro-oncogenic role of these HERV Envs (Figure 1C). This evidence concerns the gene CLEC10A and cancer.