Of note, although Siglec-15 does not show particularly close similarity with “B7 family” of immunoregulatory molecules, the expression of Siglec-15 (which was suppressed by interferon-γ) was inversely correlated with that of PD-L1 (which was induced by interferon-γ), implying that Siglec-15 targeting may be a complementary approach for the cancer patients who are refractory to PD-1/PD-L1–targeting therapies [44]. The gene discussed is CD274; the disease is cancer.