The expression and function of immunoglobulin-like transcript 4 in dendritic cells from patients with hepatocellular carcinoma

Targeting leukocyte immunoglobulin‑like receptor B2 in the tumor microenvironment: A new treatment prospect for solid tumors (Review)

Leukocyte immunoglobulin-like receptor B2 (LILRB2) functions as an immunosuppressive receptor that has a prominent role in immune regulation. The expression of LILRB2 is higher in a variety of solid malignant tumors compared with that in corresponding normal tissues. LILRB2 can be expressed in tumor cells and tumor stromal cells within the tumor microenvironment. Upregulation of LILRB2 in tumors is significantly associated with a poorer tumor phenotype, increased tolerance to certain therapeutic drugs, tumor immune escape and shorter patient overall survival time. Therefore, LILRB2 can be utilized as a novel biomarker to predict the prognosis of patients with solid malignant tumors, and targeting LILRB2 may be an effective strategy for targeted cancer therapy. The present review provides a general overview of the role and mechanisms of LILRB2 in the microenvironment of solid tumors, and emphasizes the significance of targeting LILRB2 as a promising approach for tumor-specific therapy.

Tumor-Derived Immunoglobulin-Like Transcript 4 Promotes Postoperative Relapse via Inducing Vasculogenic Mimicry through MAPK/ERK Signaling in Hepatocellular Carcinoma

The efficacy of conventional anti-angiogenesis drugs is usually low in treating hepatocellular carcinoma (HCC). Therefore, there is an urgent need to find new precise therapeutic targets and to develop more effective drugs for the treatment of HCC. Vasculogenic mimicry (VM) is different from classic endothelium-dependent angiogenesis and is associated with a poor prognosis in patients with malignant tumor. However, the mechanism underlying VM is complex and not fully defined. Ig-like transcript (ILT)-4, as a negative regulator of immune response, is expressed in many solid tumors. However, whether and how ILT4 regulates VM remains unclear. This study found VM enriched in HCC tissues, especially in tissues from patients with relapse within 5 years after surgery. Similarly, ILT4 expression level was also higher in HCC tissues from patients with relapse within 5 years after surgery. Linear regression analysis revealed a positive correlation between the expression of ILT4 and VM density. Furthermore, overexpression/knockdown of ILT4 expression upregulated/down-regulated VM-related marker, three-dimensional tube formation, and migration and invasion in HCC cell lines in vitro. In mechanistic studies, ILT4 promoted VM formation via mitogen-activated protein kinase (MAPK)/ERK signaling. This study provides a rationale and mechanism for ILT4-mediated postoperative relapse via inducing VM in HCC. The related molecular pathways can be used as novel therapeutic targets for the inhibition of HCC angiogenesis and postoperative relapse.

Cellular based treatment modalities for unresectable hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and is unfortunately associated with an overall poor prognosis and high mortality. Early and intermediate stages of HCC allow for treatment with surgical resection, ablation and even liver transplantation, however disease progression warrants conventional systemic therapy. For years treatment options were limited to molecular-targeting medications, of which sorafenib remains the standard of care. The recent development and success of immune checkpoint inhibitors has proven to be a breakthrough in the treatment of HCC, but there is an urgent need for the development of further novel therapeutic treatments that prolong overall survival and minimize recurrence. Current investigation is focused on adoptive cell therapy including chimeric antigen receptor-T cells (CAR-T cells), T cell receptor (TCR) engineered T cells, dendritic cells, natural killer cells, and tumor infiltrating lymphocyte cells, which have shown remarkable success in the treatment of hematological and solid tumor malignancies. In this review we briefly introduce readers to the currently approved systemic treatment options and present clinical and experimental evidence of HCC immunotherapeutic treatments that will hopefully one day allow for revolutionary change in the treatment modalities used for unresectable HCC. We also provide an up-to-date compilation of ongoing clinical trials investigating CAR-T cells, TCR engineered T cells, cancer vaccines and oncolytic viruses, while discussing strategies that can help overcome commonly faced challenges when utilizing cellular based treatments.