In three human cancer cell lines—human epidermoid carcinoma (skin‐derived) A‐431, human glioblastoma U‐251 MG and human osteosarcoma U‐2OS—we observed that RAD51 subcellular localisation was primarily in the nucleoli, mitochondria and cytosol (Figure 2D,E). This evidence concerns the gene RAD51 and squamous cell carcinoma.