Expression of CD39, known for its immunosuppressive effect through the release of adenosine in the tumor microenvironment (TME), on CD4+, CD8+ and Treg subsets was consistently higher at all time points in non-responders compared with responders and appeared to further increase on treatment on CD8 populations, although this did not reach significance (figure 7). This evidence concerns the gene ENTPD1 and neoplasm.