RAD51 and breast carcinoma: Interestingly, we observed that depletion or pharmacological inhibition of PAK in PAK1 overexpressing breast cancer cells, drastically reduced the expression of FANCI and FANCD2, cell survival and the ability of these cells to form Rad51 foci in response to DNA damaging agents, but in contrast, PAK inhibition only had a modest effect in these cellular processes in breast cancer cells that express low levels of PAK1.