Basic Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Dec 15, 2023; 15(12): 2138-2149
Published online Dec 15, 2023. doi: 10.4251/wjgo.v15.i12.2138
Combined TIM-3 and PD-1 blockade restrains hepatocellular carcinoma development by facilitating CD4+ and CD8+ T cell-mediated antitumor immune responses
Xu-Sheng Zhang, Hong-Cai Zhou, Peng Wei, Long Chen, Wei-Hu Ma, Lin Ding, Shi-Cai Liang, Ben-Dong Chen
Xu-Sheng Zhang, Hong-Cai Zhou, Peng Wei, Long Chen, Wei-Hu Ma, Lin Ding, Shi-Cai Liang, School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia Hui Autonomous Region, China
Ben-Dong Chen, Department of Hepatobiliary Surgery, The General Hospital of Ningxia Medical University, Yinchuan 750004, Ningxia Hui Autonomous Region, China
Ben-Dong Chen, Hepatobiliary Pancreatic Surgical, Ningxia Hepatobiliary Pancreatic Surgical Diseases Clinical Research Center, Yinchuan 750004, Ningxia Hui Autonomous Region, China
Co-first authors: Xu-Sheng Zhang and Peng Wei.
Author contributions: Zhang XS, Wei P, and Liang SC were responsible for research design; Zhou HC, Peng Wei, and Long Chen contributed to the conducting the experiments; Zhang XS, Ding L, Chen BD, and Liang SC involved in the data acquisition; Chen L, Ma WH, and Ding L participated in the data analysis; Zhou HC, Ma WH, and Chen BD wrote the manuscript; and all the authors have contributed to the completion of this paper.
Supported by the First-Class Discipline Construction Founded Project of Ningxia Medical University and the School of Clinical Medicine, No. 2020008.
Institutional review board statement: This study was conducted with the approval of the Ethics Committee of the General Hospital of Ningxia Medical University. All participants provided clinical specimens and signed the informed consent forms.
Institutional animal care and use committee statement: All animal care and experimental procedures were approved by the Ethics Committee of the General Hospital of Ningxia Medical University.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: All the data obtained in the current study were available from the corresponding authors on reasonable request.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Ben-Dong Chen, MD, Doctor, Department of Hepatobiliary Surgery, The General Hospital of Ningxia Medical University, No. 804 Shengli Street, Yinchuan 750004, Ningxia Hui Autonomous Region, China. bendong8511@nyfy.com.cn
Received: September 5, 2023
Peer-review started: September 5, 2023
First decision: September 15, 2023
Revised: October 9, 2023
Accepted: November 8, 2023
Article in press: November 8, 2023
Published online: December 15, 2023
Processing time: 99 Days and 20.6 Hours
Abstract
BACKGROUND

Immune checkpoint inhibitors (ICIs) targeting programmed cell death protein 1 (PD-1) and T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) are beneficial to the resumption of anti-tumor immunity response and hold extreme potential as efficient therapies for certain malignancies. However, ICIs with a single target exhibit poor overall response rate in hepatocellular carcinoma (HCC) patients due to the complex pathological mechanisms of HCC.

AIM

To investigate the effects of combined TIM-3 and PD-1 blockade on tumor development in an HCC mouse model, aiming to identify more effective immunotherapies and provide more treatment options for HCC patients.

METHODS

The levels of PD-1 and TIM-3 on CD4+ and CD8+ T cells from tumor tissues, ascites, and matched adjacent tissues from HCC patients were determined with flow cytometry. An HCC xenograft mouse model was established and treated with anti-TIM-3 monoclonal antibody (mAb) and/or anti-PD-1 mAb. Tumor growth in each group was measured. Hematoxylin and eosin staining and immunohistochemical staining were used to evaluate T cell infiltration in tumors. The percentage of CD4+ and CD8+ T cells in tissue samples from mice was tested with flow cytometry. The percentages of PD-1+CD8+, TIM-3+CD8+, and PD-1+TIM-3+ CD8+ T cells was accessed by flow cytometry. The levels of the cytokines including tumor necrosis factor alpha (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-6, and IL-10 in tumor tissues were gauged with enzyme-linked immunosorbent assay kits.

RESULTS

We confirmed that PD-1 and TIM-3 expression was substantially upregulated in CD4+ and CD8+ T cells isolated from tumor tissues and ascites of HCC patients. TIM-3 mAb and PD-1 mAb treatment both reduced tumor volume and weight, while combined blockade had more substantial anti-tumor effects than individual treatment. Then we showed that combined therapy increased T cell infiltration into tumor tissues, and downregulated PD-1 and TIM-3 expression on CD8+ T cells in tumor tissues. Moreover, combined treatment facilitated the production of T cell effector cytokines TNF-α and IFN-γ, and reduced the production of immunosuppressive cytokines IL-10 and IL-6 in tumor tissues. Thus, we implicated that combined blockade could ameliorate T cell exhaustion in HCC mouse model.

CONCLUSION

Combined TIM-3 and PD-1 blockade restrains HCC development by facilitating CD4+ and CD8+ T cell-mediated antitumor immune responses.

Keywords: Hepatocellular carcinoma; T cell immunoglobulin and mucin domain-containing protein 3; Programmed cell death protein 1; CD4+ T cells; CD8+ T cells

Core Tip: This study investigated the effects of combined blockade of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) and programmed cell death protein 1 (PD-1) on tumor development in a hepatocellular carcinoma (HCC) mouse model. We showed that combined TIM-3 and PD-1 blockade had more substantial inhibitory effects on tumor growth in mice compared with individual blockade. The combined therapy increased T cell infiltration and ameliorated CD4+ and CD8+ T cell exhaustion in HCC mouse model. Our findings proposed an effective immunotherapy and may provide more treatment options for HCC patients.