A previous study by Mei et al. found that ISO could promote apoptosis in canine breast cancer by down-regulating the epidermal growth factor receptor (EGFR)/signal transducer and activator of transcription 3 (STAT3)/programmed death ligand 1 (PD-L1) signaling pathway to promote apoptosis [37]. This evidence concerns the gene EGFR and breast carcinoma.