However, tumour-infiltrating Tregs present in the tumour microenvironment, especially those expressing CTLA-4, intercept dendritic cells and render them tolerogenic and anti-inflammatory, which eventually stimulates T cell exhaustion instead of activation (Facciabene et al. 2012; Gardner and Ruffell 2016; Ohue and Nishikawa 2019). This evidence concerns the gene CTLA4 and neoplasm.