Figure 3.

IQGAP1 knockout in LM2 breast cancer cells reduces spontaneous metastasis but not primary tumor growth. (A) Western blot of IQGAP1 and GAPDH in parental (WT) and clonal IQGAP1 knockout (sg) LM2 lines. Molecular weight markers in kDa are indicated. Full-length IQGAP1 is shown with an arrow. Blot is cropped for clarity, with full-length blot presented in Supplementary Fig. S7C. (B–F) Orthotopic mammary transplant of LM2 lines, with samples collected 8 weeks after injection. n = 12 mice per group. (B) Representative histology images of primary tumors showing H&E (top panels) or IQGAP1 (bottom panels) staining. Scale bar, 300 µm. (C) Distribution of primary tumor masses (g). (D) Representative images of lungs (top panels) and liver left lobes (bottom panels). Each pair of samples was taken from the same mouse. Scale bar, 10 mm. (E,F) Fraction of lung (E) or liver left lobe (F) surface area occupied by tumors, normalized to primary tumor mass (g) for each mouse. ^*P ≤ 0.05; ^**P ≤ 0.01; one-way ANOVA with Dunnett’s multiple comparisons test (all pairwise comparisons to WT).