Figure 2.

The fibrotic barrier impedes the tumor uptake of Trastuzumab, thereby diminishing the anti-tumor efficacy of Enhertu

(A and B) The anti-tumor effects of Enhertu in the treatment of gastric cancer CDX model NCI-N87 and NIH/3T3/NCI-N87 co-inoculation model. Enhertu was dosed once at 3 mg/kg by tail vein injection. Tumor volumes were recorded to show the anti-tumor effects for NCI-N87 (A) and NIH/3T3/NCI-N87 co-inoculation models (B).

(C) The red fluorescence imaging for the NCI-N87 model and NIH/3T3/NCI-N87 co-inoculation model treated with Trastuzumab Cy5.5. The mice were dosed with 3 mg/kg Trastuzumab Cy5.5. Twenty-four hours later, the in vivo fluorescence imaging was performed by IVIS system.

(D–F) The IHC staining of FAP and Sirius red staining for the NCI-N87 and NIH/3T3-NCI-N87 tumors from (C). After the red fluorescence imaging, the tumors were harvested for the pathological assays to check with the FAP expression and Sirius red intensity. The percentages of FAP positive area (E) and Sirius red positive area (F) were evaluated by ImageJ. Data represent mean ± SEM. The unpaired student’s t test was used for the statistical analysis. ∗p < 0.05. Scale bar: 100 μm.