CD28 and cancer: Top pathways were immune related including Th1 and Th2 pathways, B cell development, T helper cell differentiation, CD28 signaling in T helper cells, the complement system, T cell exhaustion signaling, various macrophage differentiation pathways, and the PD-1, PD-L1 cancer immunotherapy pathway, which is similar to the top pathway identified in Reactome, PD-1 signaling (results not shown) [22].