色瑞替尼联合PD-L1抑制剂在ALK阳性NSCLC脑转移模型中药动/药效学研究

Anaplastic lymphoma kinase (ALK) fusion positive occurs 3%-7% in patients with non-small cell lung cancer (NSCLC), and brain metastases account for almost 30%, both are serious threat to the survival of patients. Whether the combination of ceritinib with PD-L1 in the treatment of ALK-positive NSCLC is not clear, the pharmacokinetics and pharmacodynamics of the combined use are still unclear. Previous experiments showed that ceritinib could downregulate the expression of PD-L1 mRNA in H3122 cells. In addition, molecular targeted drugs can activate neonatal antigens by killing tumor cells, thereby activating the immune system, suggesting that ceritinib combined with PD-L1 inhibitors may produce synergistic effects. Therefore, we propose the "lung cancer brain metastases model-ceritinib combined with PD-L1 inhibitor-pharmacokinetic/pharmacodynamic study-action mechanism " hypothesis. There are many techniques to utilize including brain stereotaxis inoculation, in vivo brain microdialysis, liquid chromatography tandem mass spectrometry, small animal in vivo imaging to elucidate the synergistic effect and material basis of ceritinib combined with PD-L1 inhibitor in ALK-positive NSCLC brain metastases. We further explore the mechanism of action using RT-PCR technique. It is expected that the results will clarify the synergistic effect of ceritinib combined with PD-L1 inhibitors and find possible action mechanisms. Besides, expected results could provide a theoretical basis and data support for adopting ceritinib combined with PD-L1 inhibitors in ALK-positive NSCLC brain metastases patients.

ALK融合约占NSCLC 的3%~7%而肺癌脑转移约占30%，严重威胁患者的生存。色瑞替尼联用PDL1抑制剂能否协同治疗ALK阳性NSCLC脑转移尚不明确，联用的药动学、药效学基础研究尚少且调控机制不明。前期实验结果显示色瑞替尼可下调H3122细胞PDL1 mRNA表达。另外，分子靶向药可通过杀伤肿瘤细胞释放新生抗原，从而激活免疫系统，提示色瑞替尼联合PDL1抑制剂可产生协同作用。因此我们提出“肺癌脑转移模型-色瑞替尼联合PDL1抑制剂-药动/药效学研究-机制初探”假说，拟利用脑立体定位接种、在体脑微透析、液质联用、小动物活体成像等手段阐明色瑞替尼联合PDL1抑制剂在ALK阳性NSCLC脑转移模型中的协同作用和物质基础，并进一步采用RT-PCR等技术探索两者联用的作用机制。预期结果将明确色瑞替尼与PDL1抑制剂联用的协同作用并发现可能的作用机制，为两者临床联用提供理论依据和数据支持。

项目背景：非小细胞肺癌（NSCLC）约占所有肺癌的85%，间变性淋巴瘤激酶（ALK）融合基因阳性占NSCLC的3-7%，严重危害患者的生存及预后。色瑞替尼联用程序性死亡受体配体1（PD-L1）抑制剂能否协同治疗ALK阳性NSCLC尚不明确，联用的药动学、药效学基础研究尚少且调控机制不明。. 主要研究内容：本项目从临床应用和基础研究的局限性出发，通过临床药理学、药代动力学、分子生物学、细胞生物学及实验动物学等技术手段，从体外和体内两个层面探讨了色瑞替尼联用PD-L1抑制剂的药动学、药效学及分子机制。. 重要结果及关键数据：首次建立了定量测定血中色瑞替尼浓度的高效液相色谱串联质谱（LC-MS/MS）方法，对方法进行了不确定度评定以保证检测结果可靠，该方法已成功应用于色瑞替尼药动学研究。通过H2228细胞与外周血单核细胞（PBMC）共培养研究体系揭示了色瑞替尼联合PD-L1抑制剂通过ERK磷酸化途径促进淋巴细胞增殖、降低PD-L1表达、增强PBMC毒性及对癌细胞的杀伤效能发挥协同抗肿瘤作用。体内小鼠BaF3(EML4-ALK-WT)移植瘤模型结果显示，联用组的肿瘤体积和瘤重显著小于单药组，安全性良好。色瑞替尼单药组、PD-L1抑制剂单药组、联用组的相对肿瘤生长抑制率分别为84.9%、20.0%和91.9%。. 科学意义：研究结果为色瑞替尼和PD-1/PD-L1抑制剂临床联用提供重要的数据支持，也为色瑞替尼耐药的ALK阳性NSCLC患者临床治疗策略的制定提供思路和重要指导。另外，依托本课题并围绕抗肿瘤分子靶向药物，项目组也开展了一些延续/拓展性实验，为后续分子靶向药物的抗肿瘤药效学、药动学、疗效监测生物标记物的发现、肿瘤代谢重编程作用机制等研究奠定基础。