Figure 5.

Multiplexed QD profiling of four tumor biomarkers using two FFPE prostate cancer cell lines with distinct bone-metastasis behaviors. The four markers, all associated with epithelial-mesenchymal transition (EMT), are N-cadherin, EF (elongation factor)-1alpha, E-cadherin, and vimentin, and their corresponding QD colors are 565 nm, 605 nm, 655 nm, and 705 nm. The cell nuclei were counterstained blue by DAPI, and the spectra were captured under blue excitation. (a) Color fluorescence image of highly metastatic prostate cancer cells (clone ARCaPm); (b) single-cell fluorescence spectrum obtained from image (a); (c) color fluorescence image of benign prostate cancer cells (clone ARCaPe); (d) single-cell spectrum obtained from image (c). The relative abundance of these markers is consistent with previous western blotting data (not shown). Note that individual cancer cells have heterogeneous expression patterns, that the single-cell data in (b) and (d) are representative of a heterogeneous cell population.