Since blocking CD47 by antibodies could efficiently induce macrophage-mediated phagocytosis of tumor cells and treat cancers, it would be interesting to examine whether CD47 also participate in cell-in-cell formation between tumors, and if so, would blocking CD47 a feasible way to inhibit tumor growth by inducing cell-in-cell formation and the mediated-cell death? The gene discussed is CD47; the disease is cancer.