Additionally, PLCH1 may influence cell cycle progression and apoptosis by modulating proteins such as cyclin-dependent kinase 1 (CDK1), Bcl-2, and Bax.This study aims to elucidate the role of PLCH1 in breast cancer, particularly its expression and functional significance in HER2-positive and ER+/PR+ subtypes. The gene discussed is ESR1; the disease is breast carcinoma.