Fig. 6: GRP promotes activities of human prostate cancer-propagating cells.

ALDEFLUOR assay (a), quantitative analysis of ALDH-positive cancer-propagating cells (%) of DU145 (b) and PC3 (c), CD44-positive cancer-propagating cells (%) of DU145 (d), and sphere-forming capacity of DU145 (e) with treatment of GRP and/or [Tyr⁴, d-Phe¹²]-Bombesin were performed. a The number in each red frame represents the percentage of ALDH-positive cancer-propagating cells. Frequency (f) and size (g) of prostaspheres formed by FACS-purified CD44-positive cancer-propagating cells of DU45 with treatments of GRP and/or [Tyr⁴, d-Phe¹²]-Bombesin are shown. P0–P3, passages 0–3. h Average volume of PC3 tumor xenografts at indicated time points. Red arrow indicates the starting day of i.p. injection of [Tyr⁴, d-Phe¹²]-Bombesin or PBS. i Average weight of PC3 tumor xenografts at sacrifice (day 34). j ALDH-positive cancer-propagating cells (%) of PC3 tumor xenografts. *P < 0.05, **P < 0.01, ***P < 0.001. All error bars denote SD. Data represent three independent experiments (a–g), and two groups of five mice with injection of [Tyr⁴, d-Phe¹²]-Bombesin or PBS, respectively (h–j).