In particular, ss ArtIBs formed by Ca+2 were more efficient than ArtIBs (Zn+2 50:1) in maintaining a faster and progressive protein release from the SC injection site leading to a higher accumulation and longer residence time (starting at day 3 and at least until day 10) in the remote CXCR4+ tumor (Figure 3b). The gene discussed is CXCR4; the disease is neoplasm.