Advances in Promoting the Efficacy of Chimeric Antigen Receptor T Cells in the Treatment of Hepatocellular Carcinoma

Chimeric antigen receptor-T cells targeting AFP-GPC3 mediate increased antitumor efficacy in hepatocellular carcinoma

BACKGROUND AND STUDY AIMS

As a novel immunotherapy, chimeric antigen receptor T (CAR-T) cell technology is successful in treating hematologic malignancies, and exhibits potential benefits in partial solid tumors. Therapies targeting one antigen have some weaknesses, and dual-targeted CAR-T cells may be a better option. Alpha-fetoprotein (AFP) and glypican-3 (GPC3) are both highly expressed in hepatocellular carcinoma (HCC) and serve as important markers. Our study aimed to compare the cytotoxicity effect of AFP and GPC3 dual-targeted CAR-T cells on HCC cells in vitro and its therapeutic effects on a SCID xenograft model with those of single-targeted CAR-T cells.

MATERIALS AND METHODS

pLVX lentivirus vectors loaded with AFP CAR, GPC3 CAR, or AFP-GPC3 CAR constructs were transfected into human T lymphocytes. Control T, AFP CAR-T, GPC3 CAR-T, and AFP-GPC3 CAR-T cells were used as effector cells, and HLE (AFP-GPC3-), Sh-GPC3-Huh-7 (AFP+), Sh-AFP-Huh-7 (GPC3+), and Huh-7 (AFP+GPC3+) cells were used as target cells. After their co-culture for 6 h, the LDH cytotoxicity assay was employed to estimate the cell-killing effects of CAR-T cells on the target HCC cells. SCID mice bearing Huh-7 cell-derived neoplasms were injected with CAR-T cells, after which the pathological changes, CD3ζ expression, and IL-2 and IFN-γ levels in mouse tumor tissues were determined.

RESULTS

AFP and GPC3 were highly expressed in Huh-7 cells. AFP-GPC3 CAR-T cells exerted significant cell-killing effects on the HCC cells that expressed specific targeting antigen molecules (AFP and GPC3). Besides, AFP-GPC3 CAR-T cells better promoted Th cytokine secretion by Huh-7 cells than AFP CAR-T and GPC3 CAR-T cells. In vivo results suggested that AFP-GPC3 CAR-T cells better inhibited the growth of Huh-7 cell (AFP+GPC3+)-derived neoplasms than AFP CAR-T and GPC3 CAR-T cells.

CONCLUSION

AFP and GPC3 dual-targeted CAR-T cells showed better anti-tumor effects in HCC than AFP or GPC3 single-targeted CAR-T cells.

Recent Advancements in Biomaterials for Chimeric Antigen Receptor T Cell Immunotherapy

Cellular immunotherapy is an innovative cancer treatment method that utilizes the patient's own immune system to combat tumor cells effectively. Currently, the mainstream therapeutic approaches include chimeric antigen receptor T cell (CAR-T) therapy, T cell receptor gene-modified T cell therapy and chimeric antigen receptor natural killer-cell therapy with CAR-T therapy mostly advanced. Nonetheless, the conventional manufacturing process of this therapy has shortcomings in each step that call for improvement. Marked efforts have been invested for its enhancement while notable progresses achieved in the realm of biomaterials application. With CAR-T therapy as a prime example, the aim of this review is to comprehensively discuss the various biomaterials used in cell immunotherapy, their roles in regulating immune cells, and their potential for breakthroughs in cancer treatment from gene transduction to efficacy enhancement. This article additionally addressed widely adopted animal models for efficacy evaluating.

Immune-Based Combination Therapies for Advanced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fourth most frequent cause of cancer-related death worldwide. HCC frequently presents as advanced disease at diagnosis, and disease relapse following radical surgery is frequent. In recent years, immune checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced HCC, particularly with the introduction of atezolizumab/bevacizumab as the new standard of care for first-line treatment. Recently, dual immune checkpoint blockade with durvalumab plus tremelimumab has also emerged as an effective first-line treatment for advanced HCC and most of the research is currently focused on developing combination treatments based mainly on ICIs. In this review, we will discuss the rationale and ongoing clinical trials of immune-based combination therapies for the treatment of advanced HCC, also focusing on new immunotherapy strategies such as chimeric antigen receptor T cells (CAR-T) and anti-cancer vaccines.

Non-Classical HLA Class 1b and Hepatocellular Carcinoma

A number of studies are underway to gain a better understanding of the role of immunity in the pathogenesis of hepatocellular carcinoma and to identify subgroups of individuals who may benefit the most from systemic therapy according to the etiology of their tumor. Human leukocyte antigens play a key role in antigen presentation to T cells. This is fundamental to the host's defense against pathogens and tumor cells. In addition, HLA-specific interactions with innate lymphoid cell receptors, such those present on natural killer cells and innate lymphoid cell type 2, have been shown to be important activators of immune function in the context of several liver diseases. More recent studies have highlighted the key role of members of the non-classical HLA-Ib and the transcript adjacent to the HLA-F locus, FAT10, in hepatocarcinoma. The present review analyzes the major contribution of these molecules to hepatic viral infection and hepatocellular prognosis. Particular attention has been paid to the association of natural killer and Vδ2 T-cell activation, mediated by specific HLA class Ib molecules, with risk assessment and novel treatment strategies to improve immunotherapy in HCC.

Revamping the innate or innate-like immune cell-based therapy for hepatocellular carcinoma: new mechanistic insights and advanced opportunities

A cancerous tumour termed hepatocellular carcinoma (HCC) is characterized by inflammation and subsequently followed by end-stage liver disease and necrosis of the liver. The liver's continuous exposure to microorganisms and toxic molecules affects the immune response because normal tissue requires some immune tolerance to be safeguarded from damage. Several innate immune cells are involved in this process of immune system activation which includes dendritic cells, macrophages, and natural killer cells. The liver is an immunologic organ with vast quantities of innate and innate-like immune cells subjected to several antigens (bacteria, fungal or viral) through the gut-liver axis. Tumour-induced immune system engagement may be encouraged or suppressed through innate immunological systems, which are recognized promoters of liver disease development in pre-HCC conditions such as fibrosis or cirrhosis, ultimately resulting in HCC. Immune-based treatments containing several classes of drugs have transformed the treatment of several types of cancers in recent times. The effectiveness of such immunotherapies relies on intricate interactions between lymphocytes, tumour cells, and neighbouring cells. Even though immunotherapy therapy has already reported to possess potential effect to treat HCC, a clear understanding of the crosstalk between innate and adaptive immune cell pathways still need to be clearly understood for better exploitation of the same. The identification of predictive biomarkers, understanding the progression of the disease, and the invention of more efficient combinational treatments are the major challenges in HCC immunotherapy. The functions and therapeutic significance of innate immune cells, which have been widely implicated in HCC, in addition to the interplay between innate and adaptive immune responses during the pathogenesis, have been explored in the current review.