To explore the efficacy and safety of chidamide combined with endocrine in phosphoinositide-3-kinase,catalytic,alpha gene(PI3KCA) wild type hormone receptor positive(HR+)/human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer patients and to explore the efficacy and safety of Everolimus combined with endocrine therapy in patients with PI3KCA Mutant HR+/HER2- advanced breast cancer.
The age at the time of signing the informed consent form is ≥ 18 years old and ≤ 75 years old, for menopausal/premenopausal women (premenopausal women need to receive ovarian function suppression treatment at the same time).
Breast cancer patients with HR positive (ER expression ≥ 10%, PR positive or negative) and HER2 negative (Immunohistochemical(IHC)0,1+; 2+, Fluorescence in situ hybridization(FISH) not expanded) confirmed by histology.
Histologically confirmed locally advanced breast cancer (no radical local treatment) or recurrent and metastatic breast cancer.
The patients who had previously progressed after the treatment of first-line or second-line cyclin-dependent kinases 4 and 6 inhibitors（CDK4/6 inhibitors）of endocrine and whose chemotherapy was ≤ second-line (relapse during the period of new adjuvant/adjuvant treatment or within 12 months after the end of treatment was regarded as first-line chemotherapy), the PIK3CA gene mutation detection was performed a. PIK3CA Mutant subjects were enrolled in queue A; b. PIK3CA wild-type subjects were included in queue B.
Those who have received any mammalian target of rapamycin（mTOR） and histone deacetylase（HDAC） inhibitors at any time in the past.
Received chemotherapy, Targeted therapy, immunotherapy, interventional therapy or other systematic anti-tumor treatment within 4 weeks before the first administration of the study drug, or received radiotherapy within 3 weeks Note: Nitroso urea or Mitomycin C is within 6 weeks before the first use of the study drug, oral fluorouracil and small molecule targeted drugs are within 2 weeks before the first use of the study drug or within 5 half lives of the drug (whichever is longer), Traditional Chinese medicine with anti-tumor indications should be used within 2 weeks before the first use of the study drug.
Subjects who have undergone major surgical procedures or obvious trauma within 4 weeks prior to enrollment, or are expected to undergo major surgical treatment.
Subjects with brain or subdural metastasis are excluded. Unless its stability has been maintained for at least 4 weeks or Asymptomatic brain metastasis can be included in the group.