Targeting NCAM-expressing neuroblastoma with polymeric precision nanomedicine

Neural cell adhesion molecule (NCAM) expression is known to be associated with an aggressive biological behavior, increased metastatic capacity and expression of stem-cell markers in several tumor types. NCAM was also found to be expressed on tumor endothelial cells while forming new capillary-like tubes, but not on normal endothelial cells. An NCAM-targeted polymer-drug conjugate can be used both to target tumors expressing high levels of NCAM as well as the angiogenic vessels and cancer stem cells populations characterized by NCAM expression within tumors. Here, we describe the design, synthesis, physico-chemical characterization and the biological evaluation of an NCAM-targeted conjugate of polyglutamic acid with paclitaxel that was developed and evaluated on neuroblastoma, a high NCAM-expressing tumor. This conjugate inhibited tumor growth to a higher extent compared to the control conjugates and was less toxic than free paclitaxel. The dose of the conjugate could be increased at least twice than the maximum tolerated dose of paclitaxel to achieve better activity without aggravating toxicity. This work presents evidence that NCAM targeting can highly increase the efficacy of nanomedicines in the appropriate tumor models.