Fig 1.
Anti-tumor efficacy of Ab417 in a Choi-CK xenograft model.
Ab417 (10 mg/kg) or the isotype control (hFc, 3.3 mg/kg) was i.v. injected twice a week into nude mice bearing Choi-CK or TFK-1 xenografts (n = 8). Tumor volume (A), tumor weight (B), and body weight (C) were represented. Each point indicates the mean ± s.d. p < 0.05 (*) and p < 0.01 (**), significant difference from the isotype control group by Dunnett’s t-test. p < 0.05 (#), significant difference from the isotype control group by Steel’s test. (D) Tumor sections were stained with an anti-human Ki-67 antibody. Ki-67 index are represented as a percentage of positively-stained area comparing to total area.
Fig 2.
Ab417 binds to L1CAM-expressing ICC cells and reduces L1CAM levels at the membrane.
(A) Confocal microscopic analysis of Ab417 internalization. SCK-L1 cells were preincubated with Ab417 (10 μg/mL) for the indicated times. Membrane L1CAM-bound Ab417 was detected using anti-Human IgG(H+L) Cross Adsorbed DyLight 594 (red), and internalized Ab417 was detected using anti-human IgG (Fc-specific)-FITC (green). (B) Choi-CK cells were incubated with Ab417 (10 μg/mL) for the indicated times, and the membrane L1CAM was detected by western blot analysis using A10-A3 and pan-cadherin as a loading control. Control (c) indicates the cells that were incubated for 6 h without Ab417. (C) Confocal microscopic images of L1CAM staining of PBS (up)- or Ab417 (down)-treated Choi-CK tumors. The images were taken at x400 magnification. L1CAM index (D) are represented as a percentage of positively-stained area comparing to total area.
Fig 3.
Biodistribution study after injection of 64Cu-Ab417 (A) or 125I-Ab417 (B) in a Choi-CK xenograft model. After tail vein injection of radio-labeled Ab417 into Choi-CK tumor xenograft mice, mice were euthanized, and radioactivity in organs was measured (n = 3). Radioactivity in tissues is expressed as the percentage of injected dose per gram of tissue (%ID/g).
Fig 4.
Anti-tumor efficacy of gemcitabine or cisplatin in a Choi-CK xenograft model.
Drug at indicated dose was i.p. injected twice a week for 3 or 4 weeks, and tumor volume (A) and tumor weight (B) were determined. Each point indicates the mean ± s.d. p < 0.05 (*) and p < 0.01 (**), significant difference from the saline-treated group by Dunnett’s t-test. p < 0.05 (#) and p < 0.01 (##), significant difference from the saline group by Steel’s test.
Fig 5.
Anti-tumor efficacy of combined treatment with Ab417 and gemcitabine or cisplatin in a Choi-CK model.
Tumor volume (A and C) and tumor weight (B and D) are represented. Each point indicates the mean ± s.d (n = 8). p < 0.05 (*) and p < 0.01 (**), significant difference from the saline group by Dunnett’s t-test. p < 0.05 (#) and p < 0.01 (##), significant difference from the saline group by Steel’s test.