Figure 1.

Evasive Resistance to Anti-angiogenic Therapy

Py2T murine breast cancer cells were implanted into the mammary fat pad of FVB/N mice and treated with nintedanib (50 mg/kg daily p.o.) or vehicle control from day 14 after tumor cell implantation.

(A) Primary tumor growth was monitored by assessing tumor volumes over the time of therapy. Values represent mean ± SEM. n = 13 mice per group.

(B) Tumor weights were determined after 7 days of nintedanib short-term (ST) treatment. n = 6–8 mice per group.

(C–F) Cell proliferation (C and D) and the incidence of apoptosis (E and F) were quantified by immunofluorescence staining for phospho-histone 3 (pH3; red) and cleaved caspase-3 (cCasp3; red), respectively, of tumor sections from ST and LT vehicle or nintedanib-treated mice. Representative immunofluorescence microscopy pictures are shown in (D) and (F). DAPI was used to visualize cell nuclei. Values represent the number of pH3-positive (C) and cCasp3-positive (E) cells per area of each microscopic field of view. n = 5–8 mice per group. Mann-Whitney U test. ^∗p < 0.05; ^∗∗∗p < 0.001; ^∗∗∗∗p < 0.0001. The scale bars represent 50 μm.

See also Figure S1.