Chidamide Plus PD-1 Plus Paclitaxel of Neoadjuvant Treatment in Low HR Expression,HER2-negative Early Breast Cancer.

Cedaramine can effectively inhibit subtypes 1,2,3 of HDAC class I and type 10 of class IIb. Sidabamide can directly induce cycle arrest and apoptosis in tumors and has demonstrated its clinical role in lymphoma and breast cancer.besides, In recent years, many studies have found that HDAC inhibitors also have their functions in regulating immunity, Such as: 1) upregulated tumor antigen / co-stimulatory molecule / receptor levels of tumor cells (such as MHC I / II, PRAME, MIC A/B, PDL-1, etc.), Make it easier to be recognized by the immune system; 2) Initialize the natural immune system, Activating NK cell activity; 3) Initialize the acquired immune system, Activating initial T cells (Naive T cells) to target tumor antigen; 4) Increase the CD8 + effector cells that kill tumor cells, Downregulation of the immunosuppressive cells, Such as the Treg 6 7 and MDSC, Promote the formation and maintenance of acquired immune memory T cells. Preclinical studies suggested that HDAC was synergistic with PD-1 / PD-L1 antibodies and could serve as a sensitizer for PD-1 / PD-L1 antibodies. A phase I study in solid tumors found that sitabenamine combined with natureumab had an objective response rate (ORR) of 48% and a disease control rate (DCR) of 87%.Therefore, we conduct this study to observe the efficacy and safety of neoadjuvant therapy in early HR low-expression ,HER2-negative breast cancer patients treated with PD-1 mAb and paclitaxel.