Lipid raft disruption sensitizes SQ20B donor cells to radiation and induces nontargeted effects. SQ20B donor cells were preincubated for 60 min with 4 mM MBCD (lipid raft disruptor) before irradiation in the presence of MBCD. After irradiation, the medium was removed and (A) clonogenic survival was determined in donor cells. (B) Clonogenic survival of SQ20B recipient cells was co-incubated or not with MBCD before transfer of the CM from SQ20B donor cells. (C) The number of micronuclei per cell in SQ20B donor and recipient cells in the presence or absence of MBCD was quantified. (D) The percentage of cells in G2/M phase was determined using flow cytometry in SQ20B donor cells in the presence or absence of MBCD. The results are the mean ± SD of three experiments performed in triplicate. * p < 0.05, ** p < 0.01, and *** p < 0.001 compared with cells treated only with radiation. (E) The expression of cytokines secreted in the CM from untreated, irradiated (3 Gy), and MBCD + irradiated SQ20B cells was evaluated using the Human Cytokine Array (Proteome Profiler Array; R&D Systems, Minneapolis, MN, USA). For each cytokine, ImageJ software was used to determine pixel intensity.