Download This Paper
Preprints with The Lancet is a collaboration between The Lancet Group of journals and SSRN to facilitate the open sharing of preprints for early engagement, community comment, and collaboration. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early-stage research papers that have not been peer-reviewed. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. The findings should not be used for clinical or public health decision-making or presented without highlighting these facts. For more information, please see the FAQs.
Construction of PD1/CD28 Fusion Receptor Enhances Anti-Tumor Ability of c-Met CAR-T in Gastric Cancer
27 Pages Posted: 23 Dec 2020
More...Abstract
Background: Chimeric antigen receptor (CAR) T cell is a promising method in cancer immunotherapy but faces many challenges in solid tumors. One of the major problem was immunosuppression cased by PD-1.
Methods: The expression of c-Met in GC was analyzed from TCGA datasets, GC tissues and cell lines. The c-Met CAR was a second generation CAR with 4-1BB, cMet-PD1/CD28 CAR was c-Met CAR adding PD1/CD28 fusion receptor. In vitro, we measured the changes of different subgroups, phenotypes and PD-1 expression in CAR-T cells. We detected the secretion levels of different cytokines and the killing ability of CAR-Ts. In vivo, we established a xenograft GC model and observed the anti-tumor effect and off-target toxicity of different CAR-Ts.
Findings: The expression of c-Met was increased in GC. CD3+CD8+ T cells and CD62L+CCR7+ central memory T cells (TCM) were increased in two CAR-Ts. The stimulation of target cells could promote the expression of PD-1 in c-Met CAR-T. Compared with Mock T (blank control), the secretion of cytokines as IFN-γ, TNF-α, IL-6, IL-10 secreted by two CAR-Ts were increased, the killing ability to c-Met positive GC cells were enhanced. The PD1/CD28 fusion receptor could further enhance the killing ability especially the long-term anti-tumor effect of c-Met CAR-T and reduce the release level of IL-6. CAR-Ts target c-Met had no obvious off-target toxicity to normal organs.
Interpretation: The PD1/CD28 fusion receptor could further enhance the anti-tumor ability of c-Met CAR-T, and provides a promising design strategy to improve the efficacy of CAR-T in GC.
Funding Statement: This study was supported by National Natural Science Foundation of China (31770537), Key Research and Development Project of Gansu Science and Technology Plan (18YF1WA113), Special Research Project of Lanzhou University Serving the Economic and Social Development of Gansu Province (054000282)
Declaration of Interests: The authors declared they have no conflict of interest.
Ethics Approval Statement: Approval of the Ethics Committee of Lanzhou University Second Hospital and informed consent of patients. Animal experiments were approved by the Institutional Animal Care and Use Committee of Lanzhou University Second Hospital, comply with the animal welfare.
Keywords: Gastric Cancer, CAR-T, c-Met, PD1/CD28, Immunotherapy
Suggested Citation: Suggested Citation