The study, led by researchers at Sanford-Burnham Medical Research Institute, demonstrated that a previously identified tumor-penetrating peptide, iRGD, helps co-administered drugs to penetrate into extravascular tumor tissue and enhances their anticancer properties.
According to the press release announcing the findings, researchers made an unanticipated discovery that anticancer drugs do not need to be chemically attached to the iRGD peptide for iRGD to boost their efficacy. This would mean that the potential exists to enhance the efficacy of already approved drugs without creating new chemical entities.
“Drugs generally have difficulty penetrating tumors beyond a few cell diameters from a blood vessel,” said Erkki Ruoslahit, MD, PhD, distinguished professor at Sanford-Burnham Medical Research Institute. “This leaves some tumor cells with a suboptimal dose, increasing the risk of both recurrence and drug resistance. The iRGD peptide solves this problem by activating a transport system in tumors that distributes co-injected drugs into the entire tumor and increases drug accumulation in the tumor.”
Researchers also reported that in addition to being effective against human breast, prostate, and pancreatic cancers grown in mice, iRGD can penetrate other tumor types and could possibly be used to treat most, if not all, solid tumors.