Cancer-derived VEGF plays no role in malignant ascites formation in the mouse

Figure 1 Establishment of VEGF knockdown pancreatic cancer cell lines. A: Western blot showing marked reduction of VEGF expression in knockdown cells. Screening of the most effective targeting site for the VEGF gene. B: VEGF production of stable knockdown PancO2 cell clones. VEGF-WT and VEGF-KD clones (KD 1-10) were grown in 6-well plates, and the VEGF concentration in culture supernatant was measured using ELISA in triplicates. The growth medium was used as negative control (NC).

Figure 2 Effect of VEGF knockdown on cell proliferation. A: 3×10⁴ VEGF-KD7 or VEGF-WT cells were grown in 24-well plates, and the numbers of viable cells were assessed using the MTT assay at 24 (P = 0.082) and 48 h (P = 0.078) (n = 4, mean±SD); B: 2×10⁶ VEGF-KD7 or VEGF-WT cells were injected into C57BL/6 mice subicutaneous, the tumor size was measured, and the volume was calculated as [(length (mm)×width (mm)²)]/2 (n = 4, P = 0.18, mean±SD).

Figure 3 Effect of VEGF knockdown in a tumor grafted mouse ascites model. A: The ascites volume of mice inoculated with VEGF-KD7 or VEGF-WT cells (n = 5, P = 0.10, mean±SD); B: The VEGF concentration in ascites. VEGF in the ascites was measured using ELISA (n = 4, P = 0.054, mean±SD). C: 1106 VEGF-KD7 or VEGF-WT cells were inoculated into mice intraperitoneally and the mice were weighed (n = 8, P≥0.05 in each data point).