PD-1/PD-L1抑制剂在结直肠癌治疗中的现状及预后预测

结直肠癌(colorectal cancer,CRC)死亡率在世界范围内居第4位,是癌症相关死亡的一个重要原因,严重威胁患者的生存及生活质量。手术、化疗和放疗是CRC的主要治疗手段,但CRC患者的总生存率却没有显著提高,亟待寻找新的治疗手段。肿瘤免疫逃逸在肿瘤增殖、复发和转移过程中发挥着关键作用。免疫检查点程序性死亡受体1(programmed death-1,PD-1)及其配体1(programmed death-ligand1,PD-L1)在肿瘤免疫逃逸中发挥着重要作用,抗PD-1/PD-L1治疗在癌症治疗中成为研究热点。越来越多的研究提示,抗PD-1/PD-L1免疫治疗在微卫星高度不稳定(microsatellite instability-high,MSI-H)CRC治疗中已取得显著疗效。因此,本研究就抗PD-1/PD-L1疗法在CRC患者中的临床应用,以及改善其低反应率的各种策略进行了总结,并对肿瘤细胞表面PD-L1表达水平在CRC预后中的预测价值进行综述。

Current status and prognostic value of PD-1/PD-L1 in treatment of colorectal cancer

The death rate of colorectal cancer(CRC)is the fourth in worldwide.It is an important cause of cancer-related death and seriously affects the survival and quality of life of patients.Surgery,chemotherapy and radiotherapy are the main treatments for CRC.However,the overall survival of CRC patients has not been significantly improved.So the new treatments are urgently needed.Tumor immune escape plays a key role in tumor proliferation,recurrence and metastasis.Immune checkpoints programmed death-1(PD-1)and programmed death-ligand 1(PD-L1)play an important role in tumor immune escape.Anti-PD-1/PD-L1 therapy has become a hotspot in cancer research.More and more studies have showed anti-PD-1/PD-L1 immunotherapy has achieved remarkable efficacy in the treatment of microsatellite instability-high(MSI-H)CRC.Therefore,this paper summarizes the clinical application of anti-PD-1/PD-L1 therapy in the treatment of CRC and the various strategies to improve its low response rate.And the predictive value of PD-L1 expression on the surface of tumor cells in the prognosis of CRC is also reviewed.