CAR T细胞疗法在血液系统恶性肿瘤中疗效确切,但在实体瘤中迟迟难以复制,受限因素包括肿瘤趋化与浸润不足、免疫抑制性肿瘤微环境以及治疗相关不良事件[1]。靶点是另一重瓶颈:实体瘤表面具备足够肿瘤特异性表达的抗原稀缺,而针对MUC1异常Tn糖型的CAR T研究显示,异常自身抗原可成为工程化T细胞的一类靶标,并在胰腺癌异种移植模型中控制了肿瘤生长[2]。临床层面,CLDN18.2靶向CAR T在经治消化道肿瘤的I期试验中取得48.6%的客观缓解率[3];区域递送的间皮素靶向CAR T在27例恶性胸膜疾病患者中安全可行,18例联合pembrolizumab的间皮瘤患者自细胞回输起的中位总生存达23.9个月[4]。这些探索大多围绕单一抗原展开,而肿瘤异质性正是新研究试图应对的核心问题[7]。
据新消息,Diego Salas-Benito等人发表于JITC的研究探索了同时靶向间皮素(mesothelin)与MUC16的CAR T策略,并与J.R. Choo在AACR26上报告的新CAR T治疗数据相互呼应。经核实,该研究于2025年发表[7],采用tandem(串联)设计将meso与MUC16纳入同一CAR,其中MUC16以其胞外段(MUC16ecto)为靶,动机即克服肿瘤异质性[7][8];作者提出,这类T细胞对卵巢癌、胰腺癌等异质性强的肿瘤可能是有影响力的治疗策略[8]。据报道,该串联CAR的特点在于可“一次针对其中一个抗原”发挥作用[9]。
就推进而言,这一工作把此前多为单靶的临床路线(如间皮素靶向[4]、CLDN18.2靶向[3])拓展为同一CAR同时覆盖两个抗原的格局;MUC16与MUC1同属膜型黏蛋白,黏蛋白作为CAR靶点的可行性亦已有先例[2]。双靶设计能否切实应对异质性并转化为患者获益,仍有待数据检验。
需要指出的是,这条消息本身未提供任何疗效或安全性数字,J.R. Choo在AACR26报告的具体内容亦无从得知;此外,T细胞在肿瘤微环境中的耗竭与功能障碍[5]、患者预处理样本中T细胞与髓系细胞状态对CAR T体内扩增的影响[6]等实体瘤共性难题,也不会因靶点加倍而自动消解。
- 1.CAR-cell therapy in the era of solid tumor treatment: current challenges and emerging therapeutic advances · Mol Cancer 2023
- 2.Engineered CAR T Cells Targeting the Cancer-Associated Tn-Glycoform of the Membrane Mucin MUC1 Control Adenocarcinoma · Immunity 2016
- 3.Claudin18.2-specific CAR T cells in gastrointestinal cancers: phase 1 trial interim results · Nat Med 2022
- 4.A Phase I Trial of Regional Mesothelin-Targeted CAR T-cell Therapy in Patients with Malignant Pleural Disease, in Combination with the Anti-PD-1 Agent Pembrolizumab · Cancer Discov 2021
- 5.IL-10-expressing CAR T cells resist dysfunction and mediate durable clearance of solid tumors and metastases · Nat Biotechnol 2024
- 6.Immune determinants of CAR-T cell expansion in solid tumor patients receiving GD2 CAR-T cell therapy · Cancer Cell 2024
- 7.Tandem CAR-T cells targeting mesothelin and MUC16 ... · pubmed.ncbi.nlm.nih.gov 2026
- 8.T cells targeting mesothelin and MUC16 overcome tumor ... · jitc.bmj.com 2026
- 9.Tandem CAR T cells targeting mesothelin and MUC16 ... · astct.org 2026
Immunoprevention continues to gain momentum as O. Nadeem shares, “Ciltacabtagene autoleucel in high-risk smoldering myeloma: Results from the CAR-PRISM trial” at #AACR26. A #JITC position article from
@sitcancer
explores key challenges and opportunities in this evolving space:
Heat 0 · 0 likes · 0 replies · 0 reposts
Source: Journal for ImmunoTherapy of Cancer · x.com
