Interestingly, proliferation of both tumor cell lines was significantly reduced when cultured in CM of IFNγ- and TNFα-activated microglia (p < 0.001, ratios 0.51 and 0.49), but not by TGFβ1-treated microglial CM (Figure 4B, ratios 0.98 and 1.05). Here, TGFB1 is linked to neoplasm.