Brachytherapy using injectable seeds that are self-assembled from genetically encoded polypeptides in situ.

Journal Article (Journal Article)

Brachytherapy is a common clinical technique involving implantation of sealed radioactive "seeds" within a tumor to selectively irradiate the tumor mass while minimizing systemic toxicity. To mitigate the disadvantages associated with complex surgical implantation and subsequent device removal procedures, we have developed an alternative approach using a genetically encoded peptide polymer solution composed of a thermally responsive elastin-like polypeptide (ELP) radiolabeled with (131)I that self-assembles into radionuclide seeds upon intratumoral injection. The formation of these nontoxic and biodegradable polymer seeds led to prolonged intratumoral retention (~85% ID/tumor 7 days postinjection) of the radionuclide, elicited a tumor growth delay in 100% of the tumors in two human xenografts (FaDu and PC-3), and cured more than 67% of tumor-bearing animals after a single administration of labeled ELP. These results suggest that in situ self-assembly of biodegradable and injectable radionuclide-containing polypeptide seeds could be a promising therapeutic alternative to conventional brachytherapy.

Full Text

Duke Authors

Cited Authors

  • Liu, W; McDaniel, J; Li, X; Asai, D; Quiroz, FG; Schaal, J; Park, JS; Zalutsky, M; Chilkoti, A

Published Date

  • November 15, 2012

Published In

Volume / Issue

  • 72 / 22

Start / End Page

  • 5956 - 5965

PubMed ID

  • 23155121

Pubmed Central ID

  • PMC3502020

Electronic International Standard Serial Number (EISSN)

  • 1538-7445

Digital Object Identifier (DOI)

  • 10.1158/0008-5472.CAN-12-2127


  • eng

Conference Location

  • United States