In our study, immune response gene sets were also correlated with tumor downstaging in ER positive tumors, such as “KEGG antigen processing and presentation”, containing genes such as CD74, CD8A, and CD8B, and various genes of the HLA complex, as well as GO biological process gene set such as “regulation of T cell activation”, comprehending ZAP70, CD24, CD3E, LCK, IL21, among others. The gene discussed is IL21; the disease is neoplasm.