Photodynamic Molecular Beacons: An Image-Guided Therapeutic Approach to Breast Cancer Vertebral Metastases
Abstract
The vertebral column is the most common site of breast cancer metastases, where overexpression of matrix metalloproteinases (MMPs)promotes the spread of cancer. Current therapies for managing vertebral metastases have significant limitations due to high associated risk of spinal cord damage. An attractive alternative is photodynamic therapy (PDT) providing non-invasive and site-selective treatment. However, current photosensitizers are limited by their non-specific accumulation. Photodynamic molecular beacons (PPMMPB), activated by MMPs, offer another level of PDT selectivity and image-guidance preserving criticial tissues, specifically the spinal cord. In vitro studies confirm the specific activation of PPMMPB in MT-1 cells. In vivo experiments demonstrate specific activation of PPMMPB in MT-1 xenografts, using systemic and intratumoral injections. Using a clinically-relevant metastatic model, fluorescent imaging confirmed the specific activation of PPMMPB by vertebral metastases. As a first step, we validate that the metastasis-selective mechanism of PPMMPBs can specifically image breast cancer vertebral metastases, thereby differentiating tumor and healthy tissue. Preliminary PPMMPB - PDT results demonstrate the specific PDT induced destruction of vertebral metastases while the spinal cord is left undamaged.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2011
- Accession Number
- ADA542173
Entities
People
- Tracy Liu
Organizations
- University Health Network