Bispecific GPC3/PD‑1 CAR‑T cells for the treatment of HCC

Abstract

Constantly stimulated by the tumor microenvironment (TME), programmed death 1 (PD-1) is elevated, and it interacts with PD ligand 1 (PD-L1), rendering chimeric antigen receptor (CAR)-T cells dysfunctional. Hence, CAR-T cells immune to PD-1-induced immunosuppression were constructed to improve the function of CAR-T cells in hepatocellular carcinoma (HCC). Double-target CAR-T cells, targeting glypican-3 (GPC3) [a tumour-associated antigen (TAA)] and hindering PD-1-PD-L1 binding, were established. The expression of GPC3, PD-L1, and inhibitory receptors was measured using flow cytometry. The cytotoxicity, cytokine release, and differentiation level of CAR-T cells were determined using lactate dehydrogenase release assay, enzyme-linked immunosorbent assay, and flow cytometry, respectively. HCC cells were targeted and eliminated by double-target CAR-T cells. These double-target CAR-T cells limit PD-1-PD-L1 binding and sustain cytotoxicity to PD-L1 + HCC cells. The relatively low IR expression and differentiation level in double-target CAR-T cells in tumour tissues induced tumour-suppression and extended survival in PD-L1 + HCC TX models, as opposed to their single-target counterparts. The results of the present study suggested that the newly constructed double-target CAR-T cells exhibit stronger tumour-suppressing effects in HCC than their single-target counterparts, which are common, suggesting the potential of strengthening CAR-T cell activity in HCC treatment.

Chimeric Antigen Receptor T Cell Therapy for Hepatocellular Carcinoma: Where Do We Stand?

“…Double-target CAR T cells against GPC3 and PD-1 were evaluated and the results showed limited PD-1-PD-L1 binding and sustained cytotoxicity to PD-L1+ HCC cells [ 102 ]. The low expression of inhibitory receptors in double-target CAR T cells facilitated the suppression of tumor and extended survival in PD-L1+ HCC models compared to their single-target cells [ 102 ]. Jiang et al established three patient-derived xenograft (PDX) models of HCC with GPC3-positive expression [ 103 ].…”

Hepatocellular carcinoma: signaling pathways, targeted therapy, and immunotherapy

“…Two sequential phase 1 clinical trials (ClinicalTrials.gov, NCT02395250, ClinicalTrials.gov, NCT03146234) have observed antitumor activity of CAR‐GPC3 T cells in HCC patients and demonstrate that the treatment is feasible with preliminary safety 295 . Li et al 296 . established dual‐target CAR‐T cells that target GPC‐3 and PD‐1 and showed stronger tumor inhibitory effect on HCC compared with single‐target CAR‐T cells.…”

“…294 Two sequential phase 1 clinical trials (ClinicalTrials.gov, NCT02395250, ClinicalTrials.gov, NCT03146234) have observed antitumor activity of CAR-GPC3 T cells in HCC patients and demonstrate that the treatment is feasible with preliminary safety. 295 Li et al 296 established dual-target CAR-T cells that target GPC-3 and PD-1 and showed stronger tumor inhibitory effect on HCC compared with single-target CAR-T cells. In addition, disrupting PD-1 expression through Cas9/CRISPR can improve the anti-HCC effect of CAR-T cells in vitro and in vivo, suggesting the potential advantages of CAR-T cells combined with ICIs in controlling solid tumors.…”

Advances in Immunotherapy for Hepatocellular Carcinoma (HCC)

“…A novel double-target CAR-T cell therapy has been developed, recognizing GPC3 (a protein upregulated in HCC) and inhibiting PD-1, demonstrating superior therapeutic effects on HCC compared to single-target CAR-T cells. These double-target CAR-T cells showed enhanced persistence, limited inhibitory receptor expression, and potent resistance against tumor cells [76]. In a phase I clinical trial focusing on Glypican-3 (GPC3), a significant HCC-associated antigen, as a promising target for heavily treated HCC patients CT017 CAR T cells co-expressing CAR-GPC3 and RUNX3 were engineered to induce CD8+ T-cell infiltration within the cancer microenvironment.…”

“…The trial demonstrated a manageable safety profile, with all patients experiencing cytokine release syndrome (CRS) primarily at grades 2 and 3, which resolved post-treatment. Notably, one patient achieved a partial response, and two had stable disease, resulting in a 16.7% objective response rate and a 50% disease control rate [76][77][78][79].…”