highly significantp <0.001
*p <0.05 indicates significant difference, **p <0.01 indicates highly significant difference, ***p <0.001 indicates highly significant difference. 3 Results and discussion 3.1 In vitro analysis of the combined effect of CXB, ATO and IR820 The MTT assay was initially employed to evaluate the cytotoxic effects of the free drug on AKR cells and to determine the optimal combination ratio of CXB, ATO, and IR820 ( Fig. 1 A).