Our findings justified that molecular subtype (HER2E and TNBC), biomarkers (ER, PR, HER2, HR, Ki-67, nm23-H1, CK5/6, and Tau), and gene (PIK3CA) could be further explored for their possible role in first-line treatment response in Asian breast cancer clinical studies. The gene discussed is PIK3CA; the disease is breast carcinoma.