Development of a VLP-Based Vaccine Displaying an xCT Extracellular Domain for the Treatment of Metastatic Breast

Valeria Rolih1, Jerri Caldeira2, Elisabetta Bolli1

  • 1Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, 10126 Torino, Italy.

Cancers
|June 12, 2020
PubMed

Insights

A novel virus-like particle (VLP)-based vaccine, AX09, targeting xCT shows promise in preventing metastasis and improving survival for metastatic breast cancer (MBC) patients. This vaccine is advancing to clinical trials.

Area of Science:

  • Oncology
  • Immunology
  • Vaccine Development

Background:

  • Metastatic breast cancer (MBC) is a significant cause of cancer mortality, often driven by recurrence and treatment resistance.
  • There is a critical need for innovative therapies to address the unmet clinical challenges in MBC treatment.
  • Elevated xCT protein levels in invasive mammary tumors, including triple-negative breast cancer (TNBC), correlate with poor prognosis and promote metastasis.

Purpose of the Study:

  • To develop and evaluate a virus-like particle (VLP)-based vaccine (AX09) designed to inhibit de novo metastasis and extend survival in patients with MBC.
  • To engineer the MS2 bacteriophage VLP to display a key extracellular loop of xCT, a target implicated in tumor progression.

Main Methods:

  • Development of AX09, a vaccine utilizing bacteriophage MS2 VLPs engineered to display xCT extracellular loops.
  • Testing of AX09 in preclinical metastatic breast cancer mouse models.
  • Assessment of vaccine tolerability, immunogenicity (antibody response against xCT), and functional impact on xCT activity and metastasis.

Main Results:

  • AX09 was well-tolerated in MBC mouse models.
  • The vaccine successfully elicited a robust antibody response targeting xCT.
  • The induced antibody response inhibited xCT function in vitro and significantly reduced metastasis formation in vivo.

Conclusions:

  • AX09 demonstrates potential as a novel therapeutic strategy for metastatic breast cancer.
  • The vaccine's ability to inhibit xCT function and reduce metastasis warrants further clinical investigation.
  • AX09 is progressing to clinical development, offering a promising new avenue for MBC treatment.