Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation;
Sun Yat-Sen Memorial Hospital;
Sun Yat-Sen University;
Guangzhou 510120;
China;
Breast Tumor Center;
Sun Yat-Sen Memorial Hospital;
Sun Yat-Sen University;
Guangzhou 510120;
China;
Department of Thyroid and Breast Surgery;
Shenzhen Nanshan District Shekou People’s Hospital;
Shenzhen 518067;
China;
CDK4/6 inhibitor; resistance; PI3K/mTOR inhibitor; Cyclin D1; CDK4;