In Figure 3(a) of the published paper entitled “Cucurbitacin B Causes Increased Radiation Sensitivity of Human Breast Cancer Cells via G2/M Cell Cycle Arrest,” we mistakenly used the same flow cytometry data panel for the MDA-MB-231 cells treated with 2.5 μM and 5 μM cucurbitacin B. The corrected figure and legend are presented here.