Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan.
Department of Obstetrics and Gynecology, National Hospital Organization Kyoto Medical Center, Fushimi-ku, Kyoto, Japan.
Clin Cancer Res. 2021 Sep 1;27(17):4669-4679. doi: 10.1158/1078-0432.CCR-20-4459. Epub 2021 Apr 7.
Epithelial-mesenchymal transition (EMT) has been shown to play a critical role in tumor development from initiation to metastasis. EMT could be regarded as a continuum, with intermediate hybrid epithelial and mesenchymal phenotypes having high plasticity. Classical EMT is characterized by the phenotype change of epithelial cells to cells with mesenchymal properties, but EMT is also associated with multiple other molecular processes, including tumor immune evasion. Some previous studies have shown that EMT is associated with the cell number of immunosuppressive cells, such as myeloid-derived suppressor cells, and the expression of immune checkpoints, such as programmed cell death-ligand 1, in several cancer types. At the molecular level, EMT transcriptional factors, including Snail, Zeb1, and Twist1, produce or attract immunosuppressive cells or promote the expression of immunosuppressive checkpoint molecules via chemokine production, leading to a tumor immunosuppressive microenvironment. In turn, immunosuppressive factors induce EMT in tumor cells. This feedback loop between EMT and immunosuppression promotes tumor progression. For therapy directly targeting EMT has been challenging, the elucidation of the interactive regulation of EMT and immunosuppression is desirable for developing new therapeutic approaches in cancer. The combination of immune checkpoint inhibitors and immunotherapy targeting immunosuppressive cells could be a promising therapy for EMT.
上皮-间充质转化 (EMT) 已被证明在肿瘤从起始到转移的发展过程中起着关键作用。EMT 可以被视为一个连续体,具有高可塑性的中间混合上皮和间充质表型。经典的 EMT 特征是上皮细胞向具有间质特性的细胞的表型变化,但 EMT 也与其他多个分子过程相关,包括肿瘤免疫逃逸。一些先前的研究表明,EMT 与免疫抑制细胞的细胞数量有关,如髓源性抑制细胞,以及免疫检查点的表达,如程序性细胞死亡配体 1,在几种癌症类型中。在分子水平上,EMT 转录因子,包括 Snail、Zeb1 和 Twist1,通过趋化因子产生或吸引免疫抑制细胞,或促进免疫抑制检查点分子的表达,导致肿瘤免疫抑制微环境。反过来,免疫抑制因子诱导肿瘤细胞发生 EMT。EMT 和免疫抑制之间的这种反馈循环促进了肿瘤的进展。由于直接针对 EMT 的治疗具有挑战性,因此阐明 EMT 和免疫抑制之间的相互调节对于开发癌症的新治疗方法是可取的。免疫检查点抑制剂和针对免疫抑制细胞的免疫疗法的联合应用可能是 EMT 的一种有前途的治疗方法。