背景和目的

新辅助治疗（Neoadjuvant Therapy，NAT）是人表皮生长因子受体2（Human Epidermal Growth Factor Receptor 2，HER）阳性局部晚期乳腺癌（Locally Advanced Breast Cancer，LABC）的标准策略，但约40%患者因肿瘤异质性及免疫微环境调控失衡未能达到病理完全缓解（Pathological Complete Response，pCR），且缺乏有效的疗效预测体系。本研究旨在通过前瞻性评估新型抗HER2单克隆抗体——伊尼妥单抗术前治疗的疗效及安全性。同时整合多组学技术与功能实验，探索抗HER2靶向治疗与免疫系统激活的协同作用，以提升NAT的精准性。
方法
本研究纳入44例HER2阳性LABC患者，接受6-8周期TCbIP方案（紫杉类+卡铂+伊尼妥单抗+帕妥珠单抗）术前治疗，并通过倾向评分匹配（Propensity Score Matching，PSM）与TCbHP方案（曲妥珠单抗+帕妥珠单抗）患者进行疗效及安全性比较。基线时，对外周血淋巴细胞亚群进行分析，评估系统性免疫状态与治疗疗效的相关性。对术后病理残存患者进行全蛋白质组学分析，解析耐药机制。主要研究终点为pCR。此外，构建HER2阳性乳腺癌动物模型（4T1-hHER2/Balb c小鼠）探索以伊尼妥单抗为基础的治疗方案。通过蛋白印迹实验（Western Blot）、免疫组化（Immunohistochemistry，IHC）和质谱流式细胞技术等功能实验，探索各组治疗方案的疗效差异及免疫调控机制。
结果
临床疗效分析显示，TCbIP组总人群的pCR率达56.8%，PSM分析显示其tpCR率较TCbHP组提升8.6%（P>0.05），且两组的安全性相当。在激素受体（Hormone receptor，HR）阴性亚组中，TCbIP组的总pCR（total pCR，tpCR）率较TCbHP组提高21.4%（85.7% vs 64.3%，OR=3.29）。患者基线免疫特征分析显示，基线活化CD8+T细胞（CD8+HLA-DR+）水平可作为伊尼妥单抗联合治疗方案的疗效预测标志。全蛋白质组学分析表明，治疗敏感性与糖脂代谢重编程、增殖抑制及免疫微环境重塑密切相关。动物模型实验证实，伊尼妥单抗联合免疫治疗及化疗通过激活Gasdermin E（GSDME）介导的细胞焦亡通路，并与细胞外基质（Extracellular Matrix，ECM）重塑的交互作用协同增强抗肿瘤效应【肿瘤生长抑制率（Tumor Growth Inhibition Rates，TGI）较CbIP组提高超过20%】，形成“焦亡-免疫”正向循环。质谱流式细胞结果进一步表明，“靶向-免疫-化疗”三联治疗策略可有效缓解T细胞耗竭、维持记忆T细胞储备，并促进其向肿瘤微环境迁移，展现出系统性免疫激活优势。
结论
伊尼妥单抗在HER2阳性LABC术前治疗中展现出与曲妥珠单抗相似的疗效和安全性，且疗效与基线活化CD8⁺T细胞水平密切相关。伊尼妥联合方案作用机制涉及细胞焦亡与ECM重塑协同驱动的“焦亡-免疫”正向循环。未来通过基线免疫表型筛选获益人群，并联合焦亡诱导或ECM靶向策略，深化“靶向-化疗-免疫”时序化治疗模式，以实现免疫持久监视和抗肿瘤效应的平衡。

Background and aims Neoadjuvant therapy (NAT) has become the standard strategy for HER2-positive locally advanced breast cancer (LABC), approximately 40% of patients fail to achieve pathological complete response (pCR) due to tumor heterogeneity and dysregulation of the immune microenvironment, and there is a lack of effective efficacy prediction systems. This study aims to prospectively evaluate the efficacy and safety of a novel antiHER2 monoclonal antibody, Inetetamab, as a preoperative treatment. Additionally, through the integration of multi-omics technologies and functional experiments, the study will explore the synergistic effects of anti-HER2 targeted therapy and immune system activation to enhance the precision of NAT. Method This study enrolled 44 patients with HER2-positive LABC, who received 6–8 cycles of the TCbIP regimen (Taxane, Carboplatin, Inetetamab, and Pertuzumab) as preoperative treatment. The efficacy and safety were compared with those of patients receiving the TCbHP regimen (Trastuzumab and Pertuzumab) through propensity score matching (PSM). At baseline, peripheral blood lymphocyte subsets were analyzed to assess the correlation between systemic immune status and treatment efficacy. Postoperative patients with pathological residual disease underwent proteomics analysis to explore the mechanisms of drug resistance. The primary endpoint is pCR. Additionally, a HER2-positive breast cancer animal model (4T1-hHER2/Balb c mice) was established to investigate inetetamab-based therapeutic regimens. Functional experiments including Western blot, immunohistochemistry (IHC), and mass cytometry were conducted to explore both the differential therapeutic efficacy among treatment groups and the underlying immune regulatory mechanisms. Outcomes Clinical efficacy analysis revealed that the TCbIP regimen achieved a pCR rate of 56.8% in the overall population. PSM analysis demonstrated an 8.6% improvement in total pCR (tpCR) rate compared to the TCbHP group (P>0.05), with comparable safety profiles between the two groups. In the hormone receptor (HR)-negative subgroup, the TCbIP regimen significantly increased the tpCR rate by 21.4% (85.7% vs 64.3%, OR=3.29). Baseline immune profiling identified activated CD8+T cells (CD8+HLADR+) as a predictive biomarker for the efficacy of inetetamab-based combination therapy. Whole proteomic analysis indicated that therapeutic sensitivity was closely associated with glycolipid metabolic reprogramming, proliferation suppression, and immune microenvironment remodeling. Animal model experiments confirmed that inetetamab combined with immunotherapy and chemotherapy synergistically enhanced antitumor effects by activating the Gasdermin E (GSDME)-mediated pyroptosis pathway and interacting with extracellular matrix (ECM) remodeling (tumor growth inhibition rate [TGI] increased by >20% compared to the CbIP group), establishing a “pyroptosisimmunity” positive feedback loop. Mass cytometry analysis further demonstrated that the triple combination strategy of targeted therapy, immunotherapy, and chemotherapy effectively alleviates T cell exhaustion, preserves memory T cell reservoirs, and promotes their migration toward the tumor microenvironment, thereby exhibiting a systemic immune activation advantage. Conclusion Inetetamab demonstrated comparable efficacy and safety to trastuzumab in the neoadjuvant treatment of HER2-positive LABC, with clinical response closely associated with baseline levels of activated CD8⁺T cells. The therapeutic mechanism of the inetetamab-based regimen involves a pyroptosis–immunity positive feedback loop synergistically driven by pyroptosis induction and ECM remodeling. In the future, patients may be selected based on baseline immune phenotypes and treated with adjunctive pyroptosis‐inducing or ECM‐targeted agents to refine the ‘targeted– chemotherapy–immunotherapy’ temporal sequencing paradigm, thereby achieving an optimal balance between durable immune surveillance and antitumor efficacy.