We recently characterized a self-renewing subpopulation in CSC-enriched populations from four well-known human cancer-derived cell lines established from uterine cervix tumors (HeLa, SiHa, CaSki, and C-4I) [4] and found that they overexpress components of the double-strand break DNA repair machinery including RAD51 (fold change was 2.52 from HeLa SP compared with HeLa ML). This evidence concerns the gene RAD51 and cancer.