While Ifnb1 expression on mRNA level was significantly increased in B16 cells irradiated with 3 × 8 Gy, no IFN-β could be detected in the cell culture supernatant at any condition and the cytokine level inside the tumor in vivo was not affected by any treatment (Figure 10), suggesting that this pathway does not play a role in B16 melanoma. Here, IFNB1 is linked to melanoma.