Figure 6. Immune escape mediated by the IL6-JAK-STAT signaling pathway In CC. IL6 binding to its receptors to activate the JAK-STAT pathway. JAK1 phosphorylates PD-L1 to stabilize PD-L1 protein. STAT3 was involved in regulating the transcription of CD274. PD-L1 modulates the expression and activation of CD8+ T cells. CD8+ T cells acting on tumor cells.