Chittasupho et al. reported that a synthetic compound (LFC131-DOX NPs), which contained a peptide (LFC131, an inhibitor of CXCR4), PLGA nanoparticles, and doxorubicin, could specifically bind to the human lung cancer cell line A549, indicating that LFC131-DOX NPs could be used as a drug delivery system in treating lung cancer [44]. Here, CXCR4 is linked to lung cancer.