Phenotype of c-Kit⁺ HCs located in the tumor. (A) Fluorescence-activated cell sorter (FACS) analysis of cells in PC3 tumor tissue. The numbers in each quadrant represent the percentage of gated Lin^– cells. (B) Phenotype of c-Kit⁺ HCs sorted from PC3 tumor tissue by FACS. Cells fixed on glass were analyzed by May-Grünwald-Giemsa staining. M indicates mast cell. Bar indicates 10 μm. (C) FACS analysis of migrated BM cells by tumor lysates. The number in the upper right quadrant indicates the total percentage of migrated c-Kit⁺ cells. (D) Chemotaxis of c-Kit⁺ HCs in the presence of the lysates of various tumor cells. Colon26 indicates cell lysate from in vitro culture of colon26 cells; colon26-t, lysate of cells from colon26 tumor; PC3, cell lysate from in vitro culture of PC3 cells; PC3-t, lysate of cells from PC3 tumor. Results are expressed as the mean number in 3 experiments (± SEM).