我们成功地研究了HFY-4A这种新型组蛋白去乙酰化酶（HDACs）抑制剂在乳腺癌中的功能以及其潜在机制。我们用0.8、1.6或3.2μMHFY-4A处理MCF7和T47D细胞0-72h，随后进行了CCK-8、克隆形成、EdU染色、流式细胞术、Transwell和创伤愈合实验。我们进行了免疫印迹、免疫组化和ELISA实验，以检测免疫原性细胞死亡（ICD）相关蛋白的表达。我们通过染色质免疫沉淀实验证明了HFY-4A、HDAC1和肿瘤抑制基因候选2（TUSC2）之间的相互作用。进一步，我们使用异种移植小鼠模型评估了HFY-4A在乳腺癌进展中的功能。HFY-4A以剂量依赖方式抑制乳腺癌细胞的增殖、迁移和侵袭，并诱导其凋亡。HFY-4A以剂量依赖方式导致乳腺癌细胞的ICD，其表现为高迁移性团聚盒1（HMGB1）、钙调素（CRT）、热休克蛋白70（HSP70）和HSP90的显著高水平。有趣的是，HFY-4A能够通过促进TUSC2启动子上组蛋白的乙酰化来促进TUSC2的转录。救助实验的结果显示，HFY-4A通过促进TUSC2的转录来抑制乳腺癌的增殖和迁移，同时增强其凋亡和ICD。在乳腺癌异种移植小鼠模型中，HFY-4A通过上调TUSC2抑制了肿瘤生长。因此，HFY-4A能够通过促进TUSC2的转录来抑制乳腺癌细胞的增殖和迁移，并增强其凋亡和ICD。版权所有 © 2023。由Elsevier Inc.出版。

We managed to explore the function of HFY-4A, a novel histone deacetylases (HDACs) inhibitor, on breast cancer as well as its potential mechanisms. MCF7 and T47D cells were treated with 0.8, 1.6 or 3.2 μM HFY-4A for 0-72 h, following of which CCK-8, colony formation, EdU staining, flow cytometry, Transwell, and wound healing assays were carried out. Western blot, immunohistochemistry, and ELISA were conducted for assaying the expression of immunogenic cell death (ICD)-related proteins. The interaction between HFY-4A, HDAC1, and tumor suppressor candidate 2 (TUSC2) was evaluated by chromatin immunoprecipitation assay. Further, the function of HFY-4A in breast cancer progression in vivo was evaluated using xenograft mouse models. HFY-4A inhibited the proliferation, migration, and invasion, and induced apoptosis of breast cancer cells in a dose-dependent manner. HFY-4A dose-dependently caused the ICD of breast cancer cells, as evidenced by the significant high levels of high-mobility group box 1 (HMGB1), calreticulin (CRT), heat shock protein 70 (HSP70), and HSP90. Interestingly, HFY-4A could facilitate TUSC2 transcription by promoting acetylation of histones on the TUSC2 promoter. The results of rescue assays revealed that HFY-4A repressed proliferation and mobility, but enhanced apoptosis and ICD through facilitating TUSC2 transcription in breast cancer. In breast cancer xenograft mouse models, HFY-4A was verified to inhibit tumor growth via upregulating TUSC2. HFY-4A could inhibit breast cancer cell proliferation and mobility, and enhanced apoptosis and ICD through facilitating TUSC2 transcription.Copyright © 2023. Published by Elsevier Inc.