To determine whether the STAT3–TrkA interaction occurs in breast cancer cells, we immunoprecipitated endogenous p-TrkA (Y490) from MDA-MB-468 TNBC cells, and Western blot results confirm that endogenous STAT3 co-immunoprecipitates with p-TrkA (Figure 2C). This evidence concerns the gene NTRK1 and breast cancer.