CTLA4 and cancer: However, there are additional key signaling pathways in cancer immunology that have not been explored with phosphoflow cytometry, including signaling related to immune checkpoints such as PD-1, PD-L1, and CTLA-4, NF-kB, Wnt/β-catenin, PI3K-Akt-mTOR, STING, the adenosine pathway, and additional cytokines activating the JAK/STAT signaling cascade such as IL-12 and IL-15 [63–69].