NK-92MI Cells Engineered with Anti-claudin-6 Chimeric Antigen Receptors in Immunotherapy for Ovarian Cancer

• Published in: International journal of biological sciences Vol. 20; no. 5; pp. 1578 - 1601
• Main Authors: Li, Junping, Hu, Hong, Lian, Hui, Yang, Shuo, Liu, Manting, He, Jinping, Cao, Bihui, Chen, Dongni, Hu, Yuling, Zhi, Chen, Shen, Yan, Ye, Xiaodie, He, Bingjia, Zhao, Ming, Fan, Weijun, Xu, Linfeng, Leidner, Rom, Wu, Qingde, Yang, Lili, Zhang, Zhenfeng
• Format: Journal Article
• Language: English
• Published: Australia Ivyspring International Publisher 01.01.2024
• Subjects: Animals; Apoptosis; CD28 Antigens - metabolism; Cell Line, Tumor; Claudins; Female; Humans; Immunotherapy - methods; Immunotherapy, Adoptive - methods; Killer Cells, Natural; Mice; NK Cell Lectin-Like Receptor Subfamily K - metabolism; Ovarian Neoplasms - metabolism; Ovarian Neoplasms - therapy; Receptors, Chimeric Antigen - genetics; Research Paper; Claudin-6; PD-L1; NK cells; chimeric antigen receptor; ovarian cancer; PD-1
• ISSN: 1449-2288; 1449-2288
• DOI: 10.7150/ijbs.88539

: The application of chimeric antigen receptor (CAR) NK cells in solid tumors is hindered by lack of tumor-specific targets and inefficient CAR-NK cell efficacy. Claudin-6 (CLDN6) has been reported to be overexpressed in ovarian cancer and may be an attractive target for CAR-NK cells immunotherapy. However, the feasibility of using anti-CLDN6 CAR-NK cells to treat ovarian cancer remains to be explored. : CLDN6 expression in primary human ovarian cancer, normal tissues and cell lines were detected by immunohistochemistry and western blot. Two types of third-generation CAR NK-92MI cells targeting CLDN6, CLDN6-CAR1 NK-92MI cells with domains containing self-activated elements (NKG2D, 2B4) and CLDN6-CAR2 NK-92MI cells with classical domains (CD28, 4-1BB) were constructed by lentivirus transfection, sorted by flow cytometry and verified by western blot and qPCR. OVCAR-3, SK-OV-3, A2780, Hey and PC-3 cells expressing the GFP and luciferase genes were transduced. Subcutaneous and intraperitoneal tumor models were established via NSG mice. The ability of CLDN6-CAR NK cells to kill CLDN6-positive ovarian cancer cells were evaluated in vitro and in vivo by live cell imaging and bioluminescence imaging. : Both CLDN6-CAR1 and CLDN6-CAR2 NK-92MI cells could specifically killed CLDN6-positive ovarian cancer cells (OVCAR-3, SK-OV-3, A2780 and Hey), rather than CLDN6 negative cell (PC-3), in vitro. CLDN6-CAR1 NK-92MI cells with domains containing self-activated elements (NKG2D, 2B4) exhibited stronger cytotoxicity than CLDN6-CAR2 NK-92MI cells with classical domains (CD28, 4-1BB). Furthermore, CLDN6-CAR1 NK cells could effectively eliminate ovarian cancer cells in subcutaneous and intraperitoneal tumor models. More importantly, CAR-NK cells combined with immune checkpoint inhibitors, anti-PD-L1, could synergistically enhance the antitumor efficacy of CLDN6-targeted CAR-NK cells. : These results indicate that CLDN6-CAR NK cells possess strong antitumor activity and represent a promising immunotherapeutic modality for ovarian cancer.