To detect the harmful effects of IR, we measured, using qRT-PCR, the mRNA levels of IR-induced cytokines (IL-4, IL-5, IL-6, IL-11, and IL-16) and receptors (IL-4Rα, IL-7R, and IL-10Rα), which are crucial causative agents of IR-induced microenvironmental changes in the breast cancer cells, MDA-MB-231. This evidence concerns the gene IL4 and breast cancer.