IL6 and neoplasm: Additionally, immunostaining for IL-6 demonstrated significant upregulation of IL-6 in irradiated IGFBP3-expressing tumor cells (n = 5; IRS: 4.6 ± 0.8718 per section) relative to controls (n = 5; IRS: 7.6 ± 0.4 per section; p = 0.0143; Fig. 6f, g).