RAD51 and gastrointestinal stromal tumor: Importantly, when FGFR2 was knocked down by siRNA and/or inhibited with BGJ398, a selective FGFR1-4 inhibitor, IM-resistant GIST cells exhibited a reduced level of Rad51 recombinase after doxorubicin exposure, thus suggesting the attenuation of homology-mediated DNA repair mechanisms [18].