Membrane-Bound Hyaluronidase in Breast Cancer Progression
Abstract
The tumor-stroma interaction plays critical role in breast cancer progression. We hypothesize that hyaluronidase (HAase) produced by malignant tumor cells can serve as a switch to release growth factor that immobilized in extracellular matrix (ECM), and then enhance the tumor progression. We have demonstrated: (1) exogenous HAase stimulated the colony formation via shift the FGF-2 from immobilized form to free form; (2) transfection of HAase cDNA into FGF-2 high expressing SWl3 cells could stimulate colony formation; and (3) transfection HAase cDNA into MDA23 1 cells could enhance the tumor growth in CAM system. In past year, we further characterized the functions of HAase and performed the underlying mechanism studies in a great detail. The HAase expression by transfectants was confirmed by Western blot and the HAase activity was determined by ELISA like assay. The HAase released FGF-2 could be detected by Western blot. The bioactivity of FGF-2 was demonstrated by stimulation of phosphorylation of tyrosine and MAPK, which in turn, enhanced the anchorage-dependent and anchorage-independent growth of MDA23 1 -HAase transfectants. Furthermore, the conditioned media of transfectants could stimulate the growth of endothelial cells. The in vivo studies indicated that the HAase transfectants formed aggressive tumor via enhancement of angiogenesis. However, we did not see the increased metastases. We have obtained antibody against HAase by immunization of rabbit with synthetic peptide. The antibody has been further purified with affinity column and will be utilized for determination of the level of HAase expression in breast cancer samples. This study further proved that HAase play a role in tumor progression and may be a target for tumor therapy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2000
- Accession Number
- ADA389711
Entities
People
- Lurong Zhang
Organizations
- Georgetown University