Cure the Incurable? Recent Breakthroughs in Immune Checkpoint Blockade for Hepatocellular Carcinoma

Characterization and clinical verification of immune-related genes in hepatocellular carcinoma to aid prognosis evaluation and immunotherapy

BACKGROUND

Immune-related genes (IRGs) have been confirmed to play an important role in tumorigenesis and tumor microenvironment formation in hepatocellular carcinoma (HCC). We investigated how IRGs regulates the HCC immunophenotype and thus affects the prognosis and response to immunotherapy.

METHODS

We investigated RNA expression of IRGs and developed an immune-related genes-based prognostic index (IRGPI) in HCC samples. Then, the influence of the IRGPI on the immune microenvironment was comprehensively analysed.

RESULTS

According to IRGPI, HCC patients are divided into two immune subtypes. A high IRGPI was characterized by an increased tumor mutation burden (TMB) and a poor prognosis. More CD8 + tumor infiltrating cells and expression of PD-L1 were observed in low IRGPI subtypes. Two immunotherapy cohorts confirmed patients with low IRGPI demonstrated significant therapeutic benefits. Multiplex immunofluorescence staining determined that there were more CD8 + T cells infiltrating into tumor microenvironment in IRGPI-low groups, and the survival time of these patients was longer.

CONCLUSIONS

This study demonstrated that the IRGPI serve as a predictive prognostic biomarker and potential indicator for immunotherapy.

Improved anti-hepatocellular carcinoma effect by enhanced Co-delivery of Tim-3 siRNA and sorafenib via multiple pH triggered drug-eluting nanoparticles

Effective systemic treatment for hepatocellular carcinoma (HCC) remains urgently needed. Sorafenib is the first FDA-approved systemic treatment for HCC. However, individual HCC patents’ response to sorafenib varies greatly. How to enhance the anti-HCC effect of sorafenib is still a significant challenge. T cell immunoglobulin mucin-3 (Tim-3) is a newly identified immune checkpoint molecule and a promising target for HCC treatment. Herein, we developed a novel pH-triggered drug-eluting nanoparticle (CC@SR&SF@PP) for simultaneously delivery of Tim-3 siRNA and sorafenib to HCC in situ. By a single emulsification method, a representative HCC targeted-therapeutic drug sorafenib (SF) was encapsulated into the pH-triggered positive-charged mPEG5K-PAE10K (PP) nanoparticles, followed by condensing of negative-charged Tim-3 siRNA. Then, carboxymethyl chitosan (CMCS), an amphoteric polysaccharide with negative charge in the physiological pH and positive charge in the acidic environment of the tumor, was eventually adsorbed onto the surface of nanoparticles. This co-delivery nanoparticle rapidly and specifically accumulated in the tumor site of the liver and enhanced the targeted, specific and multiple release of siRNA and sorafenib. Enhanced Tim-3 siRNA transfected into tumor cells can not only directly inhibit the growth of tumor cells by knock down the expression Tim-3, but also induce the immune response and enhance the recruitment of cytotoxic T cells to kill tumor cells. The following pH-triggered sorafenib release from SF@PP NPs greatly inhibited the tumor proliferation and angiogenesis, resulting in remarkable tumor growth inhibition in a mouse hepatoma 22 (H22) orthotopic tumor model. Thus, co-delivery of Tim-3 siRNA and sorafenib via this novel pH triggered drug-eluting nanoparticle enhances their anti-tumor efficacy. We expect that such combination treatment strategy will have great potential in future clinical applications.

The Expressions and Functions of lncRNA Related to m6A in Hepatocellular Carcinoma from a Bioinformatics Analysis

Hepatocellular carcinoma (HCC) is one of the most common cancer in these days. Besides, N6-methyladenosine (m6A) plays an important role in the occurrence and development of hepatocellular carcinoma. Meanwhile, it is known to us that long noncoding RNAs (lncRNA) have the capability to control the expression of genes which means some lncRNA can adjust the expression of some m6A.Thus, it is indispensable to dig the m6A-related lncRNA in hepatocellular carcinoma about its potential regulatory mechanism and immune analysis as well as its potential drugs. In this experiment, expression profile and clinical information of lncRNA are obtained by downloading the liver cancer data set from The Cancer Genome Atlas (TCGA) database. GO enrichment analysis is used to predict potential regulatory mechanism of lncRNA. Correlation analysis of clinical parameters are calculated via chisq.test. The Cox regression model is used in univariate and multivariate analysis, and the difference is statistically significant when P < 0.05. The results show that many kinds of lncRNA have influence on the prognosis of patients with HCC, and enrichment analysis discloses some pathways that can be used to evaluate mechanism underlying in HCC. The screening of targeted drugs can provide new clues for further experiments and clinical treatment.

Advances in Immune Checkpoint Inhibitors for Advanced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is usually diagnosed in an advanced stage and has become the second deadliest type of cancer worldwide. The systemic treatment of advanced HCC has been a challenge, and for decades was limited to treatment with tyrosine kinase inhibitors (TKIs) until the application of immune checkpoint inhibitors (ICIs) became available. Due to drug resistance and unsatisfactory therapeutic effects of monotherapy with TKIs or ICIs, multi-ICIs, or the combination of ICIs with antiangiogenic drugs has become a novel strategy to treat advanced HCC. Antiangiogenic drugs mostly include TKIs (sorafenib, lenvatinib, regorafenib, cabozantinib and so on) and anti-vascular endothelial growth factor (VEGF), such as bevacizumab. Common ICIs include anti-programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1), including nivolumab, pembrolizumab, durvalumab, and atezolizumab, and anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4), including tremelimumab and ipilimumab. Combination therapies involving antiangiogenic drugs and ICIs or two ICIs may have a synergistic action and have shown greater efficacy in advanced HCC. In this review, we present an overview of the current knowledge and recent clinical developments in ICI-based combination therapies for advanced HCC and we provide an outlook on future prospects.