In order to further study the metastasis-inhibitory effect of Rad51 in human breast cancer cells, MDA-MB-231 cells harbouring a stable integration of the inducible shRAD51 were injected into separate cohorts of immunocompromised mice by orthotopic implantation and via tail vein injection after inducing knockdown of RAD51 for 96-hours with doxycycline (4 μg/ml) (Figure 4A). Here, RAD51 is linked to breast cancer.