E2F8 and fibrosarcoma: Intriguingly, however, we noticed that the intratumor T cells from mice treated with Dbp-knockdown Th9 cells exhibited a slight but statistically significant decrease in IL-4 production, but the intratumor T cells from mice treated with E2f8-knockdown Th9 cells showed increased IL-4 secretion compared to the mice treated with control T cells (Supplementary Fig. 7h) in this fibrosarcoma model, although the mechanisms and functional significance of this observation remains unknown.