Figure 1.

CX3CR1^High cancer cells are detected in patient samples from primary and metastatic breast and prostate cancers. a,b. Representative images of metastatic tumors with cancer cells showing intense CX3CR1 staining (red arrows), visualized using a StayGreen chromogen, among a majority of cells showing little or no staining for the chemokine receptor (yellow arrows). A similar scenario was observed in tissue samples from patients with primary prostate (c) and breast (d) cancers, as shown by representative images. e,f. Quantification of CX3CR1^High cancer cells was conducted by acquiring ten random fields (100,000 μm²/each) from digital micrographs for each patient sample and enumerating all cells with staining above a set threshold (see methods) using Image-J. g. Representative images showing that CX3CR1^High cancer cells co-expressed OCT4a and Nanog, which were both detected using a Vector Red chromogen by staining two consecutive tissue sections immediately following each section used for CX3CR1 staining. h. Representative images at higher magnification demonstrating co-expression of CX3CR1 and Oct4a in the same breast cancer cell. Scale bar equals 50μm.