IL6 and cancer: To further identify common gene networks between the IL-6 and REST downregulation co-regulated genes and PCa stemness and metastasis, we ran a gene set enrichment analysis (GSEA) using microarray datasets from two separate GEO databases: (1) GSE35373: PCa stromal cells versus iPS cells induced from PCa stromal cells; and (2) GSE48432: LNCaP cell versus LNCaP cells overexpressing RANKL, a gene responsible for bone metastasis of cancer cells31.