Chemokine and chemokine receptor expression on breast tumor samples. Panels A & B: CCR6 expression in breast tumors. Panel A: CCR6 negative tumor cells (× 40), and panel B: CCR6 positive tumor cells (× 40,). Panels C, D, E & F: CCR7 expression on tumor-infiltrating cells (× 20, panel C, × 20 panel D and × 40, panel E), panel F, CCR7+ infiltrating cells with dendritic cell morphology (× 20). Panels G, H, I & J: Adjacent sections (× 20 and × 40) showing elongated "fibroblastic cells" within the tumor stroma, positive for both CCR7 (panel G &H) and smooth muscle actin (SMA) (panel I & J). Panels K & L: staining of SMA (panel K) and caldesmone (panel L) showing lack of caldesmone staining of the SMA positive myofibroblastic cells. Panels M & N: CCL19/MIP3 β expression on tumor cells: panel M: negative tumor cells (× 40); panel N: positive tumor cells (× 40); Panel O & P: CCL19 (panel O, × 20) and CD1a (panel P, × 40) expression on cells with dendritic cell morphology in the tumor stroma. Bars are all 50 microns.