Additionally, CD39 expression was accompanied by the expression of co-inhibitory receptors (i.e., lymphocyte activating 3, T cell immunoreceptor with Ig and ITIM domains, PD-1, T-cell immunoglobulin mucin family member 3, and 2B4) on T cells and was associated with tumor growth (33, 34). This evidence concerns the gene ENTPD1 and neoplasm.