CD8A and neoplasm: In contrast, primary resistant tumours upregulate immunosuppressive signalling pathways, including sphingosine kinase‐1 (SK1) resulting in a reduced CD8/T‐reg cell ratio and increased immunosuppressive cytokine expression,62 WNT/β‐catenin resulting in dendritic cell and T‐cell exclusion63 and IFN‐γ signalling pathway defects resulting in attenuated tumour cell apoptosis and growth suppression.64