CASP3 and neoplasm: The present data revealed a significant (p ≤ 0.05) decrease in caspase-3 level by − 78.9% in the tumor tissue when compared to the control, Fig. 6E. In response to different treatments of CuNPs and irradiation, the level of caspase-3 was significantly (p ≤ 0.05) elevated (EC/CuNPs, EC/R, and EC/CuNPs/R groups) by 529.8, 614.0, and 824.6%, respectively, when compared to untreated EC group.