Coadministration of a Tumor-Penetrating Peptide Enhances the Efficacy of Cancer Drugs

Abstract

Penetrating Attack on Tumors While considerable research effort in oncology is focused on the design of new cancer drugs, an important but relatively understudied research area is the development of methods that optimize the delivery and tumor penetration of existing cancer drugs. Previous work has characterized a peptide (iRGD) that selectively targets and penetrates tumor tissue by virtue of its specific interaction with tumor blood vessels. Now, studying mouse models, Sugahara et al. (p. 1031 , see the cover) show that coinjection of the iRGD peptide increases the tumor penetration and antitumor activity of several cancer drugs, including the cytotoxic agent doxorubicin and the therapeutic antibody trastuzumab (Herceptin), without increasing their harmful effects on healthy tissue. Importantly, these effects did not require chemical conjugation of the cancer drugs to the peptide.