Jag1/Notch调控肿瘤相关巨噬细胞诱导乳腺癌赫赛汀耐药的研究

Herceptin resistance is an important issue to be solved in the breast cancer field. TAMs play an important role in the progression and drug resistance of breast cancer cells. Previous studies found that the differentiation of TAMs depended on the activation of the Notch signals. We have confirmed that the effect of herceptin therapy in breast cancer was negatively correlated with the expression of Jag1 and Notch1, negatively with the infiltration of TAMs and Treg, positively with the infiltration of NK and CD4+T cell in tumor tissue. We used multiplex bioassay to detect TAMs in the tissue of drug-resistant patients and found the expression of CXCL2, IL-6, TGF-β, and other factors increased significantly. On the basis of these foundings, through in vivo and in vitro experiments, as well as clinical samples, this study will validate that Jag1/Notch is the main initiating factors of TAMs; TAMs promote Treg and iDCs generation, Treg promote TAMs generation in turn; TAMs could also inhibit the ADCC effects of NK and T cell, and exacerbate herceptin resistance. We will use herceptin -resistant cell lines, model animals and the tumor tissue of herceptin-resistant patients, combined with a variety of research methods, in order to clarify the key factors that Jag1/Notch induce TAMs differentiation, continuously amplify immunosuppressive effects and form immunosuppressive microenvironment.The study is expected to provide the basis of the combination of multiple targets to reverse herceptin resistance.

赫赛汀耐药是乳腺癌领域亟待解决的重要问题，TAMs在乳腺癌发生发展和治疗抵抗中发挥重要作用，TAMs的分化依赖于Notch信号的激活。我们发现：赫赛汀疗效与乳腺癌组织中Jag1、Notch1表达以及免疫细胞浸润相关；芯片技术检测耐药患者TAMs中细胞因子、趋化因子，发现CXCL2、IL-6、TGF-β等升高。基于前期结果，我们假设：TAMs的分化依赖于Jag1/Notch信号的激活；TAMs通过分泌细胞因子，活化EGFR/HER-2/MAPK通路诱导耐药；TAMs与Treg、iDCs相互促进，构成环路，形成免疫抑制基质，不断放大TAMs的作用；TAMs还可抑制NK和T细胞的ADCC效应，促进赫赛汀耐药。我们应用耐药细胞系、模式动物及耐药患者肿瘤组织，结合多种研究方法，阐明Jag1/Notch诱导TAMs分化进而形成免疫抑制基质的关键分子节点，为从多靶点联合治疗逆转赫赛汀耐药提供理论依据。

赫赛汀耐药是乳腺癌领域亟待解决的重要问题，TAMs在乳腺癌发生发展和治疗抵抗中发挥重要作用，TAMs的分化依赖于Notch信号的激活。我们前期发现：赫赛汀疗效与乳腺癌组织中Jag1、Notch1表达以及免疫细胞浸润相关；芯片技术检测耐药患者TAMs中细胞因子、趋化因子，发现CXCL2、IL-6、TGF-β等升高。我们应用耐药细胞系、模式动物及耐药患者肿瘤组织，结合多种研究方法，证实Jag1/Notch信号活活化可促进TAMs的分化进而诱导乳腺癌赫赛汀耐药。耐药TAMs细胞因子CXCL2和IL-6表达升高，通过单抗证实耐药TAMs通过CXCL2诱导Treg的分化，而耐药 TAMs可通过 IL-6不仅抑制CD3+CD4+T细胞和CD3+CD8+T细胞的生成，还降低CD3+CD4+T细胞中PD-1的表达，耐药 TAMs也使得NK 细胞的ADCC活性显著下降，形成免疫抑制基质，不断放大TAMs的免疫抑制作用，促进赫赛汀耐药。在本研究中我们不但证实了Jag1/Notch诱导TAMs分化进而形成免疫抑制基质，诱导乳腺癌赫赛汀耐药，再其中耐药TAMs、PD-1、以及细胞因子CXCL2和IL-6是关键分子节点，因此抑制肿瘤所致 TAMs 的生成，打破以 TAMs为核心的“免疫抑制基质”，增强 NK 细胞和 T 细胞相关的 ADCC 效应，都将是极有临床应用价值的逆转赫赛汀耐药的有效手段。