Genito-urinary cancer: mechanisms of metastasis
Prostate cancer has a predilection to metastasize to the bone marrow - a stage of disease that remains incurable. There is therefore a need to elucidate the mechanism of metastatic spread of malignant prostate epithelial cells to the bone marrow.
See: Figure 1: Metastatic prostate cancer
In order to metastasise, malignant cells have to bind to and invade through endothelial barriers. We have developed a series of in vitro co-culture assays to model the bone environment to allow the study of cell to cell interactions involved in the metastatic process.
See: Figure 2: metastasis
In vitro models of metastasis
Binding assays
Model developed to investigate the specific interaction between the bone marrow endothelium and prostate epithelial cells. Coupled with the confocal microscope this will allow the determination of key component in this interaction.
Invasion assays
Prior to forming a bone metastasis, a prostate epithelial cell must invade through two barriers, the bone marrow endothelial cell layer and a basement membrane. The invasion chamber model places a barrier, bone marrow endothelial cells, basement membrane or both between the malignant cells and the bone marrow stroma. The model can then be used to assess invasion stimuli, enzymes/ factors involved in invasion and anti invasion agents.
See: Figure 3: Invasion chamber
Co-culture assays
The group has access to human primary bone marrow stroma. Co-culture of prostate cancer cell lines or malignant primary prostate epithelial cells with bone marrow stroma mirrors the environment of a bone metastasis. This model can be used to assess the effect of anti metastatic agents on the ability of malignant prostate epithelial cells to form colonies within the bone marrow. See:
- Figure 4: Co-culture assay
- Figure 5: Control
- Figure 6: Matrix metalloproteinases (MMP) and Urokinase Plasminogen Activator (uPA) expression).
Confocal microscopy
Use of microscopy in the Z plane enables the researcher to follow a prostate epithelial cell in real time as it invades through different media, Bone Marrow Endothelial Cells/ Bone Marrow Stroma/ Basement Membranes.
See: Figure 7: TLI (wmv video clip)
In vitro drug assessment
Utilising the above models the group can determine the mode of action of potentially therapeutic anti metastatic agents.