Skip to main content
. 2024 May 21;30(15):3298–3315. doi: 10.1158/1078-0432.CCR-23-3110

Figure 6.

Figure 6.

ADC growth inhibition of orthotopic TNBC xenografts in vivo.A, Staining for EGFR was confirmed using FFPE blocks of cell line xenografts of known EGFR expression pattern (see Fig. 3A; EGFR-high/positive: MDA-MB-468, HCC1143, MDA-MB-231, SUM149; EGFR-low: CAL51, MCF7), compared with human normal breast glandular epithelium and normal tonsil. Scale bar, 100 μm. B, Effects of ADC treatment on tumor growth in vivo. (i) Orthotopic tumor growth of MDA-MB-468 and CAL51 xenografts (n = 4) treated with vehicle, SNS-032 (5 mg/kg), cetuximab, isotype ADC, or ADC (7.5 mg/kg, weekly injection for 4 weeks). P values determined by one-way ANOVA. (ii) Body weight measurement. C, IHC evaluation of EGFR in a TMA of 38 PDX samples established from 35 patients (28 TNBC, five ER+, and two HER2+; disease characteristics: Supplementary Table S2). Representative images showing various staining intensities across samples (scale bar, 100 μm). Pathologists scored the TMA spots for EGFR positivity: score 0, no membrane staining; score 1, weak incomplete membrane staining in >10% cells; score 2, moderate complete membrane staining in >10% cells or strong complete membrane staining in ≤10% cells; score 3, strong (intense and uniform) complete membrane staining in >10% cells. D, Pie chart showing out of 38 PDX samples: 47.4% (n = 18, gray) were negative for membrane EGFR expression; 39.5% (n = 15, yellow) were score 1; 10.5% (n = 4, orange) were score 2; 2.6% (n = 1, red) is highly positive (score 3). E, Microarray-based EGFR mRNA expression was compared with membrane EGFR staining positivity tested by IHC. P value determined by two-tailed unpaired t test. F, Effects of ADC treatment on KCL004 PDX tumor growth in vivo. Left, representative tumor images after two doses of isotype ADC or ADC, where no visible residual tumor was found in any mice treated with ADC during the experimental timeframe. (i) KCL004 PDX orthotopic tumor growth (n = 5) with isotype-ADC or ADC treatment (two doses, 10 mg/kg). (ii) Body weight measurements. P values determined by one-way ANOVA.