PIK3CA and breast carcinoma: Comparing the expression of PIK3CA, SRC, and NOS3 in normal breast tissue and breast cancer tissue in TCGA database, it can be found that after CKI treatment, the expression of PIK3CA, SRC, and NOS3 in BC cells tends to be in normal tissue, suggesting that CKI may regulate the VEGF signaling pathway by reversing the abnormal expression of PIK3CA, SRC, and NOS3.