With the final aim of developing an effective antitumor and antimetastatic drug against this cancer, we started to explore the selectivity of the biodistribution to the tumor tissue and the possible toxicity of the protein-based nanocarrier T22-GFP-H6, which was previously developed by our group and targets CXCR4 [37]. The gene discussed is CXCR4; the disease is neoplasm.