The vast majority of immunosuppressive agents are currently available in the clinic, including neurocalcin inhibitors (CsA or FK506), cytotoxic drugs (mycophenolate mofetil), and corticosteroids, which are effective in controlling AR by inhibiting the activation and proliferation of CD4+ and CD8+ T cells rather than preventing chronic rejection and cancer progression in patients [28]. Here, CD4 is linked to cancer.