Seven cytokines are significantly secreted by both infected brain tumour cells (CXCL1, IL-1 alpha, IL-6, CXCL10 (IP-10), CCL3, CCL4 and CCL5 (RANTES)), six from infected USP7 cells only (CCL11, IL-4, IL-8 (CXCL8), IL-9, IL-21 and SDF-1 alpha) and five from infected USP13 cells only (GM-CSF, IFN alpha, IL-1 beta, IL-1RA and IL-5) (Fig. 5B). Here, IL21 is linked to brain neoplasm.