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The immune microenvironment and progression of immunotherapy and combination therapeutic strategies for hepatocellular carcinoma

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Hepatoma Res 2021;7:3.
10.20517/2394-5079.2020.107 |  © The Author(s) 2021.
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Abstract

Hepatocellular carcinoma (HCC) accounts for 75%-85% of all primary liver cancers and is the leading cause of cancer-related deaths. China accounts for almost half of the global incidence and deaths of HCC. The poor response of chemotherapeutics and targeted drugs may be due to the drug resistance, heterogeneity of HCC, severe chronic liver damage and cirrhosis. Restoration of the liver microenvironment changes caused by chronic injury is crucial. Immunotherapy recently seems to show promise for the treatment of HCC induced by inflammatory injury. However, the unique liver immune system and resident immune tolerance state also pose a challenge for HCC immunotherapy. Different combinations of strategies have been developed for enhancement of HCC treatment. Here, we will discuss the immune microenvironment and progression of immunotherapy and combination therapeutic strategies for HCC.

Keywords

Immune microenvironment, immunotherapy, immune checkpoint inhibitors, Chimeric antigen receptor T, hepatocellular carcinoma

Introduction

Hepatocellular carcinoma (HCC) accounts for 75%-85% of all primary liver cancers. Due to the rapid progression of HCC, the lack of effective treatment programs, and poor prognosis makes it the fourth leading cause of cancer-related deaths[1]. Due to regional differences in medical diagnosis and treatment, more than half of the new cases and deaths of HCC each year occur in the Asia-pacific region. Patients with early HCC in Europe and United States can be diagnosed and effectively treated in time[2]. More than 70% of HCC patients do not benefit from medical therapy. The vast majority of HCC patients present with an advanced stage at diagnosis, and the most effective surgical programs are often challenging to implement. In the past ten years, dozens of promising chemotherapeutics have failed the phase III trial, with only sorafenib demonstrating a low objective response rate and a slight increase in survival[3]. Research on targeted drugs for cell proliferation, metastasis and angiogenesis are encouraging, such as regorafenib and lenvatinib, although the overall survival rate remains dissatisfactory[4]. The ineffectiveness of chemotherapeutics and targeted drugs may be due to drug resistance and heterogeneity of HCC. HCC is usually accompanied by severe chronic liver damage and cirrhosis. Hence, anti-HCC drugs require a good balance of therapeutic response and drug toxicity and this often limits the application of highly active compounds with high toxicity[5,6]. Therefore, restoration of the liver microenvironment caused by chronic injury should be incorporated in the holistic management of HCC. In recent years, immunotherapy has been used in the treatment of various solid tumors. This was observed through the checkpoint inhibition of programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) and cell toxic T lymphocyte-associated protein 4 (CTLA-4) while improving the tumor immune microenvironment which seems to be particularly relevant for the treatment of HCC. However, the unique liver immune system and resident immune tolerance state make it different from other organs. Besides, continuous matrix remodeling of the malignant hepatocyte transformation caused by chronic inflammation and scars has created an immunosuppressive microenvironment that promotes the development of HCC, posing a challenge for HCC immunotherapy[7].

The immune microenvironment of the liver and HCC

The liver has a unique immune regulation and balance mechanism. On one hand, the portal vein system is directly exposed to gastrointestinal pathogens and requires an effective immune response. On the other hand, it needs to deal with a large number of harmless blood antigens and maintain the immune tolerance of the liver[8]. In most cases, the liver is in a physiological immune tolerance state[9]. Most non-parenchymal cells, such as live sinusoidal endothelial cells (LSEC), Kupffer cells (KCs) and hepatic dendritic cells (HDC), gather in the liver sinusoids. It constitutes the physiological basis of the liver’s immunosuppressive microenvironment[10,11]. LSEC has the dual functions of immune surveillance and immune tolerance. It acts as an antigen-presenting cell (APC) to present pathogens or tumor antigens[12]. At the same time, it inhibits the excessive responses of DC and T lymphocytes to bacterial antigens from the portal system[13-15]. KCs maintain immune tolerance by engulfing pathogenic microorganisms derived from the intestine, secreting inhibitory factors (such as IL-10 and prostaglandins) and activating the proliferation of regulatory T cells (Tregs)[16-19]. Besides, HDC is also a component of the liver immune tolerance by reducing the expression of MHC II and co-stimulatory molecules[20]. In summary, this immune-tolerant physiological environment creates a huge obstacle to the host’s anti-tumor immunity.

The pathogenesis of HCC is characterized by destruction of the sinusoidal structure by a viral infection and inflammatory injury, impairment of immune surveillance and immune tolerance functions leading to liver cirrhosis and liver cancer[6,10]. The high-risk factors of HCC (hepatitis virus, alcohol, aflatoxin, etc.) drive hepatocyte DNA damage, endoplasmic reticulum stress and necrosis, which in turn leads to the formation of regenerative nodules, proliferative nodules and ultimately HCC[21]. HCC has abundant immune cell infiltration, which is the immune response of the host trying to clear the tumor. Unfortunately, this immune response is often dysregulated[22]. Tumor-infiltrating lymphocytes (TILs) account for a high proportion of HCC[23,24], but these ineffective TILs often prove to be insufficient to control tumor growth[25]. The increased FoxP3+ Treg may impair the effector function of CD8+ T cells, which exacerbates the immunosuppressive microenvironment in HCC and is associated with a poor prognosis[26]. In addition, adaptive immune cells (such as CD8 + T cells, Th17 cells and B cells) can also stimulate the development of HCC[27,28]. There are a large number of bone marrow-derived suppressor cells (MDSCs) and Tregs in the microenvironment of HCC, which evade immune surveillance through a variety of mechanisms, such as the expressing high-levels of SOCS3 and IL-10 to limit immune cell activation[29] and secretion fibrosis factor TGF-β. This is used to build an environment of immunosuppression and drug resistance[30], and directly down-regulates the expression of T cells or NK cell activation ligands (MHC class I and NKG2D, etc.)[31,32]. Therefore, the immunosuppressive environment of HCC is an arduous challenge to the host’s immune system, which makes immunotherapy a promising approach for HCC treatment in the future.

The strategies of HCC immunotherapy

According to the immunological basis of HCC, we divide current HCC immunotherapy into four categories, including immune checkpoint inhibitors, oncolytic virus therapy, HCC vaccine and chimeric antigen receptor T (CAR-T) cell therapy [Figure 1]. Due to the destruction of the HCC sinusoidal structure, it is difficult for LSEC and HDC to complete the antigen presentation process. Therefore, the specific DC vaccine is obtained by impinging tumor-associated antigen (TAA) or tumor lysate into DC in vitro. It activates cytotoxic T lymphocytes (CTLs) through major histocompatibility complex (MHC) class II-TCR antigen presentation and CD40/CD80/CD86-CD28 interaction. CTLs recognize and destroy tumor cells containing HCC-related antigens on MHC class I molecules. In addition to blocking the antigen presentation process, cancer cells will evade CTLs by upregulating immune checkpoint ligands, such as PD-L1 binding to the PD-1 receptor on the surface of CTLs to exhaust it, and CTLA-4 blocking the interaction between CD40/CD80/CD86 and CD28. Therefore, antibodies against PD-L1/PD-1 and CTLA-4 are used for immune checkpoint inhibitor therapy of HCC. The other alternative is more direct, by cloning in vitro chimeric antigen receptor T cells that can target specific antigen genes [such as Glypican 3 (GPC3) or alpha-fetoprotein (AFP)] related antigens to directly kill tumor cells. Finally, genetically engineered oncolytic virus therapy can also selectively replicated in tumors, killing cancer cells while stimulating antigen presentation and adaptive anti-tumor immune responses.

The immune microenvironment and progression of immunotherapy and combination therapeutic strategies for hepatocellular carcinoma

Figure 1. The immune microenvironment and immunotherapy for HCC. We divide current HCC immunotherapy into four categories, namely immune checkpoint inhibitors, oncolytic virus therapy, HCC vaccine and chimeric antigen receptor T (CAR-T) cell therapy. HCC: hepatocellular carcinoma

Immune checkpoint inhibitors

Tumor cells express a variety of immunosuppressive ligands on their surface, which bind to the indicated inhibitory receptors of activated T cells involved in the anti-tumor response. This process in turn reduces the intensity of the anti-tumor immune response, thereby evading immune surveillance[33]. Drugs that block these immunosuppressive targets to eliminate tumor immune escape are called immune checkpoint inhibitors (ICI). PD-1 is a member of the CD28 superfamily and is expressed on the surface of T cells and B cells. Its activation will lead to the phosphorylation of ITSM (Immunoreceptor tyrosine-based switch motif) in the cytoplasm of the cell, inhibiting energy metabolism in T cells, thereby hindering cell cloning proliferation and secretion of cytokines. In order to avoid the killing of T cells, tumor cells highly express PD-L1 and release the PD-L1 into the peripheral blood, which causes the exhaustion of T cells and the loss of tumor antigen presentation ability of myeloid immune cells[34]. Therefore, targeted inhibition of the interaction of PD-1 and PD-L1 is of great significance for the treatment of HCC.

Nivolumab, as the first PD-1 targeted drug to be used in clinical practice, was initially used in the treatment of melanoma, and its objective response rate and one-year survival rate were 40.0% and 72.9%, respectively[35]. Subsequently, Nivolumab was tried to treat advanced HCC. Among 144 HCC patients, 20% showed a good response to nivolumab, and 3 of them achieved complete remission (CR), highlighting the potential of Nivolumab to treat advanced HCC[36]. Another anti-PD-1 targeted drug Pembrolizumab has also shown effectiveness in the treatment of advanced HCC, with an objective response rate and a one-year survival rate of 17% and 54%[37]. In fact, a single ICI is not satisfactory for the treatment of advanced HCC. The current ICI therapy is mostly performed in a variety of combinations (for example, anti-PD-L1 antibody plus anti-CTLA-4 antibody), which is more effective than a single agent. In the absence of targetable lymphocytes in the tumor microenvironment, inhibition of PD-1/PD-L1 cannot stimulate cancer immunity, and inhibition of the CTLA-4 can cause CD8 + T cells to proliferate in the lymph nodes and infiltrate the tumor tissue, thereby enhancing the efficacy of anti-tumor. In fact, combination therapy of molecularly targeted drugs and immune checkpoint inhibitors has received considerable attention. For example, immunosuppressive cytokines that cause the immunosuppressive liver environment of patients with liver cancer, such as interleukin (IL)-10, transforming growth factor (TGF)-β and vascular endothelial growth factor (VEGF) molecular targeted drugs[38,39]. Table 1 shows the ongoing use of ICI in combination with various interventions (such as kinase inhibitors, cytokine or receptor inhibitors, and embolotherapy).

Table 1

Clinical trials of immune checkpoint inhibitors for HCC

Clinical trials identifierTargetStatusActive treatmentNPrimary endpoints or outcomesRef.
Single immune checkpoint inhibitors
   NCT03630640PD-1Recruiting Phase 2Nivolumab50OS, 2 years
   NCT03383458PD-1Recruiting, Phase 3Nivolumab530Recurrence-free Surviva, 49 months; OS, 7 years;
Time to recurrence, 49 months
   NCT04161911PD-1Completed Phase 3Nivolumab1,426OS, 7.75 years
Combination of immune checkpoint Inhibitors
   NCT03222076CTLA-4
PD-1
Recruiting Phase 2Ipilimumab
Nivolumab
45AEs, 5 years
   NCT03682276CTLA-4
PD-1
Recruiting, Phase I/IIIpilimumab
Nivolumab
32AEs, 127 Days;
Delay to surgery, 89 Days
   NCT03510871PD-1
CTLA-4
Not yet recruiting, Phase IINivolumab
Ipilimumab
40The percentage of subjects with tumor shrinkage, 4 years
Combination of Immune Checkpoint Inhibitors with Tyrosine kinase inhibitor
   NCT04310709Multikinase
PD-1
Recruiting, Phase IIRegorafenib
Nivolumab
42ORR, 6 months[40-42]
   NCT04170556Multikinase
PD-1
Recruiting, Phase IIRegorafenib
Nivolumab
60AEs, 24 months
   NCT03299946Multikinase
PD-1
Active, not recruiting, Phase ICabozantinib
Nivolumab
15AEs, 4 years
   NCT03841201Multikinase
PD-1
Recruiting, Phase IILenvatinib
Nivolumab
50ORR, 6 months
   NCT03418922Multikinase
PD-1
Active, not recruiting Phase 1Lenvatinib
Nivolumab
30DLTs, 28 days
   NCT03006926Multikinase
PD-1
Phase 1; Active, not recruitingLenvatinib
Pembrolizumab
104AEs, 3 years;
DLT, 21 days;
ORR, 3 years
   NCT02856425Multikinase PD-1Phase 1; RecruitingNintedanib
Pembrolizumab
18MTD, 24 months
   NCT02572687PD-L1
VEGF
Phase 1; Active, not recruitingRamucirumab
MEDI4736
114DLTs, 28 days
   NCT02576509Raf-1
PD-1
Active, not recruiting, Phase IIISorafenib
Nivolumab
743OS, 41 months
   NCT02988440Raf1
PD-1
Phase 1; CompletedPDR001
Sorafenib
20AEs, 30 days;
DLT, 8 weeks;
   NCT03893695ALK-1
PD-1
Recruiting Phase 1 Phase 2GT90001 Nivolumab20DLTs, 28 days
   NCT03059147PI3k
PD-1
Active, not recruiting, Phase IISF1126
Nivolumab
14DLTs, 56days
   NCT03655613C-Met
PD-1
Recruiting Phase 1 Phase 2APL-101
Nivolumab
119DLTs, 35 days
   NCT02795429PD-1+cMetPhase 1/2; Active, not recruitingPDR001
INC280
90DLT, 42 days;
ORR, 3 years
Combination of immune checkpoint inhibitors with Cytokine/receptor inhibitor
   NCT02423343TGFβR1
PD-1
Active, not recruiting Phase 1 Phase 2Galunisertib
Nivolumab
75MTD, 6 months
   NCT04123379PD-1
CCR2/CCR5
Recruiting Phase 2Nivolumab BMS-813160
BMS-986253
50Primary pathologic response: 2 years; Significant tumor necrosis: 2 years
Combination of immune checkpoint inhibitors with embolotherapy
   NCT03033446Embolotherapy PD-1Recruiting, Phase IIRadioembolization
Nivolumab
40ORR, 8 weeks
   NCT03380130PD-1
Embolotherapy
Active, not recruiting Phase 2Nivolumab SIR-Spheres40AEs, 2 years[43,44]
   NCT03572582PD-1
Embolotherapy
Active, not recruiting Phase 2Nivolumab
TACE
49ORR, 42 months
   NCT04268888PD-1
Embolotherapy
Recruiting Phase 2 Phase 3Nivolumab and TACE/TAE522OS: 2 years;
TTTP
Multiple combination therapy
   NCT01658878PD-1
Raf-1
CTLA-4
multikinase
Active, not recruiting, Phase I/IINivolumab
Sorafenib
Ipilimumab
Cabozantinib
1,097AEs, 100 days;
ORR, 6 months
[45,46]
   NCT04039607PD-1
CTLA-4
Raf-1
VEGFR/FGFR
Recruiting, Phase IIINivolumab
Ipilimumab
Sorafenib
lenvatinib
1,084OS, 4 years
   NCT04472767PD-1
CTLA-4
Multikinase
Embolotherapy
Not yet recruiting, Phase IINivolumab
Ipilimumab
Cabozantinib
Transarterial Chemoembolization
35Percentage of Progression-free Survival, 6 Months;
Complete Response Rate, 1 year
   NCT04050462PD-1
Multikinase
IL-8
Not yet recruiting, Phase IINivolumab
Cabiralizumab
BMS-986253
74ORR, 6 years
   NCT03071094Oncolytic therapy
PD-1
Active, not recruiting, Phase I/IIPexastimogene Devacirepvec;
Nivolumab
30DLTs, 4Weeks;
ORR, 6 months
   NCT03897543PD-1
INK T cells Agonist
Recruiting Phase 1 Phase 2Nivolumab
ABX196
48AEs, 1 year

Oncolytic virus therapy

The oncolytic virus can specifically host in cancer cells, replicate and destroy the cell structure and hence was not initially classified as immunotherapy. Subsequent studies confirmed that oncolytic viruses could induce anti-cancer immune responses and immunogenic cancer cell death, making them a form of immunotherapy[47]. Compared with traditional therapies, oncolytic virus therapy is safer, has the selective specificity of host cancer cells, and continuously self-replicates to lyse cancer cells[48]. In the tumor microenvironment, pathogen-associated molecular patterns (PAMP) of oncolytic viruses can be recognized by pattern recognition receptors (PRR) of immune cells, such as through TLR or MDA5 activation of macrophages or dendritic cells[49,50]. As a secondary effect, oncolytic viruses enhance the recognition and presentation of tumor antigens, and activate the infiltration of cytotoxic T cells into tumors[51]. Therefore, oncolytic virus therapy is a very interesting method to overcome HCC immunosuppression. Currently, oncolytic virus therapies used for HCC include dsDNA or ssRNA viruses, such as measles vaccine virus (MeV), herpes simplex virus (HSV), adenovirus (Adenovirus) and vaccinia virus (VV), etc., which are used to engineer infection vectors[52]. For example, inserting the overexpression sequence of granulocyte-macrophage colony-stimulating factor (GM-CSF) into the oncolytic virus sequence, GM-CSF recruits myeloid cells in the periphery to enhance the immune response in the tumor microenvironment[53]. So far, preclinical studies for HCC oncolytic virus therapy have been very encouraging. We have compiled preclinical studies on HCC oncolytic therapy for the past ten years, as shown in Table 2.

Table 2

Representative Oncolytic therapy used in preclinical studies

Virus strainModificationTherapeutic geneHCC cell linesAnimal modelDoseRef.
Recombinant VSV-NDV, L289AReplaced of hemagglutinin-neuraminidase (HN)NoneHepG2 Huh7NOD.CB17-prkdcscid/NCrCrl (NOD-SCID).107 TCID50,IV[54]
Getah-like alphavirus, M1Insertion of valosin-containing protein (VCP) inhibitorsXBP1Hep3BHep3B xenografts,
Nonhuman primate Macaca fascicularis.
5 × 105 PFUs, IV
1 × 109 PFUs, IV
[55]
HSV, d0-GFPMutated in glycoprotein K and glycoprotein BNoneHuh7, SMMC7721, QGY7703, L-02, BEL7404, GSG7701, HCCLM3, MHHC97H, H22Huh7 and Hep3B xenografts BALB/c.1 × 107 PFU, IV
Ad5Insertion of Golgi protein 73 (GP73) promoter and sphingosine kinase 1 (SphK1)-short hairpin RNA (shRNA)SphK1Huh7, HL-7702Huh7 xenografts BALB/c nude mice.6 × 108 PFU, IT
Recombinant influenza viral, PR8deletion in NS and insertion of h GM-CSFhGM-CSFMDCK, A549, SMCC7721,HepG2HepG2 xenografts BALB/c nude mice.2 × 109 PFU, IT[56]
MeV, MV-EdmNoneNoneCC-LM3, MHCC-97HLM3 xenografts BALB/c nude mice.5 × 106 PFU, IT[57]
Ad, Ad-spInsertion of Vestigial-Like Family Member 4 (VGLL4)VGLL4Hep3B, Huh-7Huh-7 xenografts BALB/c nude mice.5 × 108 PFU, IT[58]
HSV, HSV T-01α47 and γ34.5 loci are deleted and the LacZ gene replaces the ICP6 geneNoneHuH-7, Li-7 JHH-1, JHH2, JHH5, JHH6, JHH7, HLE, HLF, PLC/PRF/5, huH-1Hepa1-6 xenografts BALB/c nude mice.2 × 106 PFU, IT[59]
Ad, Ad-ΔBInsertion of ING4 and TRAILING4 and TRAILHep3BHep3B xenografts BALB/c nude mice.1 × 1010 PFU, IV[60]
Ad, Ad-wnt-E1A(Δ24bp)-TSLC1Insertion of TSLC1Wnt and Rb pathwayMHCC-97H, PLC/PRF/5PLC/PRF/5 xenografts BALB/c nude mice.6 × 108 PFU, IT[61]
Ad, OAV SG655-mGMPInsertion of 11R-P53 and GM-CSF11R-P53 and GM-CSFHep3B-C, ECCG5ECCG5 xenografts BALB/c miceUnknow[62]
Ad, Ad-ΔB/TRAIL and Ad-ΔB/IL-12Mutated in E1A and deleted in E1B regions. Insertion of hTRAIL or hIL-12hTRAIL or hIL-12Hep3B and HuH7Athymic nude mice, orthotopic model2 × 108 PFU, IV 1 × 1010 PFU, IV[63]
MeV, (Res + MeV)Encoding of GFP as a marker gene and SCD as suicide geneNoneHepG2 and Hep3BNo animal model usedVarious MOIs[64]
VV, GLV-2b-372Deletion of TK and insertion of TurboFP635 geneNoneHuh-7, Hep G2, SNU-449, and SNU-739Athymic nude mice Huh-7 xenograft1 × 105 PFU, IT[65]
VV, GLV-1 h68Deletion of TK and insertion of Renilla luciferasegreenNoneHuh-7, Hep 3B, SNU-449 and SNU-739No animal model usedVarious MOIs[66]
Ad, TelomelysinhTERT inserted upstream of the E1 genehTERTHuman: Huh-7, Hep3B, PLC5, HA22T, HCC36, and HepG2 Mouse: Hepa-1c1c7 and Hepa 1-6HBx transgenic mice, orthotopic model1.25 × 108 PFU, IT
6.25 × 108 PFU, IT
3.0 × 108 PFU, IT
[67]
HSV, G47ΔICP47 and γ34.5-deletionNoneHepG2, HepB, SMMC-7721, BEL-7404, and BEL-7405Balb/c nude mice SMMC-7721, BEL-7404 xenograft2 × 107 PFU, IT[68]
HSV, LCSOVViral glycoprotein H gene linked with liver-specific apolipoprotein E (apoE)-AAT promoter. miR-122a complimentary sequence to the 3ʹ untranslated region (3ʹUTR). miR-124a and let-7 also inserted at 3ʹ UTRmiR122, miR-124a and let-7HuH-7, HepG2, and Hep3BHsd: athymic (nu/nu) mice, Hep3B xenograft5 × 106 PFU, IT[69]
VV, GLV-1 h68Deletion of TK and insertion of Renilla luciferasegreen fluorescent protein (Ruc-GFP), β-galactosidase, β-glucuronidaseNoneHuH7 and PLC/PRF/5Athymic Nude-Foxn1nu HuH7 and PLC xenografts5 × 106 PFU, IV[70]
Ad, SG7011let7TInsertion of eight copies of let-7 target sites (let7T) into the 39 untranslated region of E1AmiRNA, let-7HepG2, Hep3B, PLC/PRF/5, and Huh7Hep3B and SMMC-7721 xenografts BALB/c nude mice.5 × 108 PFU, IT[71]
VV, JX-963Deletion of TK and VGF, insertion of h GM-CSFhGM-CSFNoneImmunocompetent, orthotopic, NZW rabbits VX2 tumor modelVarious PFU, IV[72]

Although many preclinical research attempts have been made in oncolytic therapy in recent years, there are still very few programs that have entered the clinical stage. At present, the only HCC oncolytic virus entering clinical research is JX-549, with VV as an engineered vector. VV has the stability and efficiency of intravenous administration, is widely used in the safety of live vaccines, has the advantages of immune-inducing activity and better editability, and has become a carrier of various engineered tumor-melting viruses[73-75]. The thymidine kinase gene (TK) gene of JX-594 (also known as PexaVec; Jennerex Inc.) was deleted to make it more specific for cancer cell infection. In addition, hGM-CSF and β-galactosidase were inserted to enhance its immunostimulatory activity and replication capabilities[73,76,77]. JX-594 showed complete tumor response and systemic efficacy in a phase I clinical study[78]. In the phase II trial, low-dose JX-594 has significant anti-cancer effect and immune activation ability[79], but this requires earlier interventional therapy[80]. Currently, a large-scale 600-person multicenter Phase 3 trial is still in progress (NCT02562755). More clinical studies of HCC oncovirus are shown in Table 3.

Table 3

Clinical trials of oncolytic viral therapy for HCC

Clinical trials identifierStatusActive treatmentnPrimary end points or outcomesRef.
NCT03071094Active, not recruiting.
Phase 1 and 2 trials
     JX-594;
     Nivolumab
30DLTs, 4 weeks;
ORR, 6 months
NCT02562755Active, not recruiting.
Phase 3 trials
     JX-594;
     Sorafenib
600OS, 53 months
NCT00554372Completed. Phase 2 trials     JX-59430mRECIST v1.0 criterion;
Choi criterion. 4 weeks
[81]
NCT01387555Completed. Phase 2b trials     JX-594;129OS, 21 months[82]
NCT00629759Completed.
Phase 1 trials
     JX-59414MTD, Safety evaluation throughout study participation[83]

HCC vaccine

Tumor vaccine is a treatment program to increase the specificity of tumor antigens, mainly antigen peptide vaccines and DCs vaccines, which are used to stimulate specific immune responses. The clinical trials of therapeutic vaccines for HCC are summarized in Table 4. At present, there are relatively few registered clinical trials for DCs vaccines in HCC, partly because of the unsatisfactory results of previous clinical trials of such vaccines[86]. On the other hand, the tumor heterogeneity of HCC also limits the development of a single antigen peptide or DCs vaccine. With the development of large-scale DNA sequencing technology, patient-specific multi-target peptide or DCs vaccine is still a promising strategy for the treatment of HCC. DC, as professional antigen-presenting cells (APC), recognize, process and present TAA. Allogeneic DC vaccines can provide T cells with antigens and co-stimulatory molecules needed for immune response. In short, DCs are mobilized from peripheral blood and their expansion is stimulated with GM-CSF to produce DCs for reinfusion. Prior to this, DC needs to be exposed to TAA to trigger the specificity of the vaccine[87]. DCs can be transduced with DNA or RNA encoding known TAA, or directly co-cultured with patient tumor lysate[88]. Phase I clinical studies have shown that the allogeneic DCs vaccine can produce a specific immune response in 73% of HCC patients[89].

Table 4

Clinical trials of therapeutic vaccines for HCC

Clinical trials identifierStatusActive treatmentnPrimary endpoints or outcomesRef.
NCT04248569Recruiting, Phase IDNAJB1-PRKACA peptide vaccine, Nivolumab, Ipilimumab.12DLTs, 4 weeks; Fold change in interferon-producing DNAJB1-PRKACA-specific CD8+ and CD4+ T cells, 12 weeks;
NCT03674073Recruiting, Phase INeoantigen Vaccines; Microwave Ablation24CTCAE v4.0, 1 year
NCT02409524Completed, Phase IIIndividualized anti-cancer vaccine (CRCL-AlloVax)15OS, 12 weeks
NCT01974661Completed, Phase ICOMBIG-DC vaccine (ilixadencel).18Registration of adverse events. 0.5 years[84]
NCT03203005Completed, Phase I/IIIMA970A vaccine; CV8102 adjuvant; Cyclophosphamide.22Registration of adverse events, 2 years; Immunogenicity, 2 years
NCT00005629Completed, Phase I/IIAlpha-fetoprotein peptide-pulsed autologous dendritic cell vaccine6Safety, 1 month
NCT00022334Completed, Phase I/IIAlpha-fetoprotein peptide-pulsed autologous dendritic cell vaccine33DLT and MTD, 1 year
NCT04147078Recruiting, Phase INeoantigen-primed dendritic cell (DC) cell vaccine80DFS, 5 years
NCT04251117Recruiting, Phase, I/IIaPersonalized neoantigen DNA vaccine (GNOS-PV02) and plasmid-encoded IL-12 (INO-9012) in combination with pembrolizumab (MK-3475)12CTCAE v5.0, 2 years
Immunogenicity, 2 years
NCT02089919Completed, Phase I/IICancer stem cell vaccine40Adverse events. 3 months[85]
NCT00028496Completed, Phase IRecombinant fowlpox-CEA(6D)/TRICOM vaccine48DLT and MTD, 56 days.
NCT03942328Recruiting, Phase IAutologous dendritic cells and Prevnar vaccine26Adverse events. 1 year
NCT02232490Recruiting, Phase IIIHepcortespenlisimut-L (V5) therapeutic vaccine120Changes in plasma AFP, 3 months

Chimeric antigen receptor T cell therapy

In addition to immune checkpoint inhibitors, oncolytic viruses and vaccines, adoptive therapy using genetically modified T cells have also become one of the potential immunotherapy options for HCC. T cells can be engineered to express a chimeric antigen receptor (CAR), which is composed of a T cell receptor CD3ζ chain and co-stimulatory receptors (e.g., CD28 and TNFRSF9) to form an antigen recognition domain[90]. The antigen recognition domain endows CAR-T cells with specificity for tumor-associated antigens, which shows promise in the treatment of HCC. Besides, CAR-T cells have a strong adaptive immunity and can recognize antigens that are not present in MHC molecules. CAR-T cell therapy has been used in the preclinical treatment of a variety of solid tumors, but there are few clinical studies on HCC, and more are still in the preclinical research stage. Like the HCC vaccine, the technical difficulty lies in the choice of tumor-specific antigens[91]. CD133 is expressed by cancer stem cells derived from various epithelial cells and is an attractive cancer treatment target. CAR-T cells targeting CD133 have shown the feasibility of treating advanced HCC, with controllable toxicity and effective activity[92]. Glypican-3 (GPC3) is a member of the heparan sulfate glycoprotein family and belongs to a transmembrane glycoprotein. It plays an important role in cell proliferation, differentiation and metastasis. CAR-T cells targeting glypican-3 can inhibit the growth of HCC[93,94]. Besides, there are HCC recognition antigens such as NKG2D[95] and CD147[96] for CAR-T cell transformation. In addition, the CAR of CAR-T cells can be inserted into the expression of a variety of cytokine genes to overcome the immunosuppressive effects of the HCC microenvironment[97,98]. The clinical trials of CAR-T cell therapy for liver cancer are summarized in Table 5.

Table 5

Clinical trials of Chimeric antigen receptor T cell therapy for liver cancer

No.TitleStatusConditionsInterventionsURL
1Study evaluating the efficacy and safety With CAR-T for liver cancerUnknown statusLiver neoplasmsBiological: EPCAM-targeted CAR-T cellshttps://ClinicalTrials.gov/show/NCT02729493
2Clinical study of ET1402L1-CAR T cells in AFP expressing hepatocellular carcinomaTerminatedHepatocellular carcinoma|liver cancerBiological: autologous ET1402L1-CART cellshttps://ClinicalTrials.gov/show/NCT03349255
3T cells co- expressing a second generation glypican 3-specific chimeric antigen receptor with cytokines interleukin-21 and 15 as immunotherapy for patients with liver cancer (TEGAR)WithdrawnHepatocellular carcinoma|hepatoblastomaGenetic: TEGAR T cells|drug: cytoxan|drug: fludarabinehttps://ClinicalTrials.gov/show/NCT04093648
4Glypican 3-specific chimeric antigen receptor expressed in t cells for patients with pediatric solid tumors (GAP)RecruitingLiver CancerGenetic: GAP T cells| drug: cytoxan|drug: fludarahttps://ClinicalTrials.gov/show/NCT02932956
5Safety and Efficacy of CEA-targeted CAR-T therapy for relapsed/refractory CEA+ cancerRecruitingSolid Tumor|Lung CancerBiological: CEA CAR-T cellshttps://ClinicalTrials.gov/show/NCT04348643
6Autologous CAR-T/TCR-T cell immunotherapy for solid malignanciesRecruitingEsophagus cancer|hepatoma|glioma|gastric cancerBiological: CAR-T/TCR-T cells immunotherapyhttps://ClinicalTrials.gov/show/NCT03941626
7A Study of MG7 redirected autologous T cells for advanced MG7 positive liver metastases (MG7-CART)Unknown statusLiver MetastasesBiological: MG7-CARThttps://ClinicalTrials.gov/show/NCT02862704
8A Study of CD147-targeted CAR-T by hepatic artery infusions for very advanced hepatocellular carcinomaRecruitingAdvanced hepatocellular carcinomaBiological: CD147-CARThttps://ClinicalTrials.gov/show/NCT03993743
9CAR-T hepatic artery infusions and Sir-Spheres for liver metastasesCompletedLiver MetastasesBiological: anti-CEA CAR-T cells|Device: Sir-Sphereshttps://ClinicalTrials.gov/show/NCT02416466
10CAR-T hepatic artery infusions or pancreatic venous infusions for CEA-expressing liver metastases or pancreas cancerActive, not recruitingLiver MetastasesBiological: anti-CEA CAR-T cellshttps://ClinicalTrials.gov/show/NCT02850536
11Hepatic transarterial administrations of NKR-2 in patients with unresectable liver metastases from colorectal cancerActive, not recruitingColon Cancer Liver MetastasisBiological: NKR-2 cellshttps://ClinicalTrials.gov/show/NCT03370198
12Dose escalation and dose expansion phase I study to assess the safety and clinical activity of multiple doses of NKR-2 administered concurrently with FOLFOX in colorectal cancer with potentially resectable liver metastasesActive, not recruitingColon Cancer Liver MetastasisBiological: NKR-2 cellshttps://ClinicalTrials.gov/show/NCT03310008
13Interleukin-15 armored Glypican 3-specific chimeric antigen receptor expressed in T cells for pediatric solid tumorsNot yet recruitingLiver Cancer|Rhabdomyosarcoma, et al.Genetic: AGAR T cells|drug: cytoxan|drug: fludarahttps://ClinicalTrials.gov/show/NCT04377932
14Treatment of relapsed and/or chemotherapy refractory advanced malignancies by CART133CompletedLiver Cancer|Pancreatic Cancer, et al.Biological: anti-CD133-CAR vector-transduced T cellshttps://ClinicalTrials.gov/show/NCT02541370
15Autologous CAR-T/TCR-T cell immunotherapy for malignanciesRecruitingSolid tumorsBiological: CAR-T cell immunotherapyhttps://ClinicalTrials.gov/show/NCT03638206
16A study of chimeric antigen receptor T cells combined with interventional therapy in advanced liver malignancyUnknown statusCarcinoma, Hepatocellular|Pancreatic Cancer, et al.Drug: CAR-T cellhttps://ClinicalTrials.gov/show/NCT02959151
17A clinical research of CAR T cells targeting EpCAM positive cancerRecruitingHepatic Carcinoma, et al.Biological: CAR-T cell immunotherapyhttps://ClinicalTrials.gov/show/NCT03013712
18NKG2D-based CAR T-cells immunotherapy for patient with r/r NKG2DL+ solid tumorsNot yet recruitingHepatocellular Carcinoma|Glioblastoma, et al.Biological: NKG2D-based CAR T-cellshttps://ClinicalTrials.gov/show/NCT04270461
19GPC3-T2-CAR-T cells for immunotherapy of cancer with GPC3 expressionRecruitingHepatocellular Carcinoma, et al.Biological: GPC3 and/or TGF-beta targeting CAR-T cellshttps://ClinicalTrials.gov/show/NCT03198546
20NKG2D CAR-T(KD-025) in the treatment of relapsed or refractory NKG2DL+ tumorsNot yet recruitingSolid Tumor|Hepatocellular Carcinoma, et al.Drug: KD-025 CAR-T cellshttps://ClinicalTrials.gov/show/NCT04550663
21GPC3-CAR-T Cells for the hepatocellular carcinomaNot yet recruitingHepatocellular CarcinomaBiological: GPC3-CAR-T cellshttps://ClinicalTrials.gov/show/NCT04506983
22CAR-T cell immunotherapy for HCC targeting GPC3WithdrawnGPC3 Positive Hepatocellular CarcinomaBiological: CAR-T cell immunotherapyhttps://ClinicalTrials.gov/show/NCT02723942
23Clinical Study on the efficacy and safety of c-Met/PD-L1 CAR-T cell injection in the treatment of HCCUnknown statusPrimary Hepatocellular CarcinomaBiological: c-Met/PD-L1 CAR-T cell injectionhttps://ClinicalTrials.gov/show/NCT03672305
24A study of GPC3 redirected autologous T cells for advanced HCCUnknown statusCarcinoma, HepatocellularDrug: TAI-GPC3-CART cellshttps://ClinicalTrials.gov/show/NCT02715362
25GPC3-targeted CAR-T cell for treating GPC3 positive advanced HCCRecruitingHepatocellular CarcinomaBiological: CAR-T cell immunotherapyhttps://ClinicalTrials.gov/show/NCT04121273
26A Study of GPC3-targeted T cells by intratumor injection for advanced HCC (GPC3-CART)Unknown statusCarcinoma, HepatocellularDrug: GPC3-CART cellshttps://ClinicalTrials.gov/show/NCT03130712
27Phase I/II study of anti-Mucin1 (MUC1) CAR T cells for patients with MUC1+ advanced refractory solid tumorUnknown statusHepatocellular Carcinoma, et al.Biological: anti-MUC1 CAR T cellshttps://ClinicalTrials.gov/show/NCT02587689
28Anti-GPC3 CAR T for treating patients with advanced HCCCompletedHepatocellular CarcinomaBiological: anti-GPC3 CAR Thttps://ClinicalTrials.gov/show/NCT02395250
29Anti-GPC3 CAR-T for treating GPC3-positive advanced hepatocellular carcinoma (HCC)Unknown statusHepatocellular CarcinomaBiological: retroviral vector-transduced autologous T cells to express anti-GPC3 CARs|drug: fludarabine|drug: cyclophosphamidehttps://ClinicalTrials.gov/show/NCT03084380
30Clinical study of redirected autologous T cells with a chimeric antigen receptor in patients with malignant tumorsActive, not recruitingHepatocellular Carcinoma, et al.Genetic: CAR-CD19 T cell|genetic: CAR-BCMA T cell|genetic: CAR-GPC3 T cell|genetic: CAR-CLD18 T cell|drug: fludarabine|drug: cyclophosphamidehttps://ClinicalTrials.gov/show/NCT03302403
31A clinical research of CAR T cells targeting CEA positive colorectal cancer (CRC)Not yet recruitingStage III Colorectal Cancer|Colorectal Cancer Liver MetastasisBiological: Anti-CEA-CAR Thttps://ClinicalTrials.gov/show/NCT04513431
32Study of anti-CEA CAR-T + chemotherapy vs. chemotherapy alone in patients with CEA+ pancreatic cancer & liver metastasesNot yet recruitingMalignant tumor of pancreas metastatic to liverBiological: anti-CEA CAR-T cells|drug: gemcitabine/nab paclitaxel|drug: NLIR+FU/FA|drug: capecitabinehttps://ClinicalTrials.gov/show/NCT04037241
33Glypican 3-specific chimeric antigen receptor expressing T cells for hepatocellular carcinoma (GLYCAR)RecruitingHepatocellular CarcinomaGenetic: GLYCAR T cells|drug: cytoxan|drug: fludarabinehttps://ClinicalTrials.gov/show/NCT02905188
344th generation chimeric antigen receptor T cells targeting glypican-3RecruitingAdvanced Hepatocellular CarcinomaDrug: CAR-GPC3 T cellshttps://ClinicalTrials.gov/show/NCT03980288
35PD-1 antibody expressing CAR-T cells for EGFR family member positive advanced solid tumor (lung, liver and stomach)Unknown statusPD-1 Antibody|CAR-T cells|advanced solid tumorBiological: HerinCAR-PD1 cellshttps://ClinicalTrials.gov/show/NCT02862028
36Chimeric antigen receptor T cells targeting glypican-3RecruitingHepatocellular carcinomaBiological: CAR-GPC3 T cellshttps://ClinicalTrials.gov/show/NCT03884751
37A clinical study in patients with high-risk recurrent primary hepatocellular carcinoma using autologous TILsActive, not recruitingHepatic CarcinomaDrug: tumor infiltrating lymphocytehttps://ClinicalTrials.gov/show/NCT04538313
38CAR-GPC3 T cells in patients with refractory hepatocellular carcinomaCompletedHepatocellular CarcinomaGenetic: CAR-GPC3 T cellshttps://ClinicalTrials.gov/show/NCT03146234

The current combination of therapeutic strategies for HCC

Currently, there are many immunotherapy and other target therapy drugs approved by the Food and Drug Administration (FDA) of The United States of America (USA) for liver cancer treatment, including Atezolizumab, Avastin (Bevacizumab), Bevacizumab, Cabometyx (Cabozantinib-S-Malate), Cyramza (Ramucirumab), Keytruda (Pembrolizumab), Lenvatinib Mesylate, Lenvima (Lenvatinib Mesylate), Nexavar (Sorafenib Tosylate), Nivolumab, Opdivo (Nivolumab), Pemazyre (Pemigatinib), Pembrolizumab, Pemigatinib, Ramucirumab, Regorafenib, Sorafenib Tosylate, Stivarga (Regorafenib), Tecentriq (Atezolizumab). Single agent therapy has historically shown poor results in HCC, leading to trials of combination therapy for a more efficacious outcome. For example, the FDA has approved Opdivo (nivolumab) + Yervoy (ipilimumab) based on the CheckMate 040 trial, atezolizumab + bevacizumab for patients with advanced HCC based on the IMbrave150 (NCT03434379) study. The CheckMate 040 is a multicentered, open-labelled, multicohort, phase 1/2 study. The result showed that nivolumab + ipilimumab had manageable safety, promising objective response rate, and durable responses. The arm A regimen (4 doses nivolumab 1 mg/kg + ipilimumab 3 mg/kg every 3 weeks then nivolumab 240 mg every 2 weeks) received accelerated approval in the US based on this study[99]. The IMbrave150a study is a global, open-labelled, phase 3 trial for patients with unresectable HCC who had not previously received systemic treatment. The study included 336 patients in the atezolizumab + bevacizumab group and 165 patients in the sorafenib group. The result showed that atezolizumab + bevacizumab resulted in better overall (overall survival at 12 months was 67.2% vs. 54.6%) and progression-free survival (6.8 months vs. 4.3 months) outcomes than sorafenib[100]. There are many different combinations of immune checkpoint inhibitors with other different therapeutic strategies under investigation. Some of the combination clinical trials are concluded in the Table 1.

Conclusion and prospect

Immunotherapy is a revolution in HCC treatment. Significant responses have been observed in various tumor types with immunotherapy, especially immune checkpoint inhibitors and CAR-T cells. However, it is clear that not all HCC patients are sensitive to current immunotherapy, and even in those who do respond, the effect is difficult to last. Lots of data indicate that most HCCs are immunosuppressive tumors. Therefore, ongoing research using a multifaceted approach to enhance the activity of the immune environment remain underway to enhance current immunotherapy strategies.

Declarations

Authors’ contributions

Drafted the outline of this review: Feng ZY, Xia HP

Drafted the manuscript: Feng ZY, Xu FG, Liu Y, Xu HJ, Wu FB, Chen XB, Xia HP

Finalized the manuscript: Chen XB, Xia HP

Availability of data and materials

Not applicable.

Financial support and sponsorship

This work was supported by grants from the National Natural Science Foundation of China (82072739), The Recruitment Program of Overseas High-Level Young Talents, “Innovative and Entrepreneurial Team” [No.(2018) 2015], Science and Technology Development Fund of Nanjing Medical University and Chinese Foundation for Hepatitis Prevention and Control-TianQing Liver Disease Research Fund (TQGB20190164, TQGB20200139).

Conflicts of interest

All authors declared that there are no conflicts of interest.

Ethical approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Copyright

© The Author(s) 2021.

REFERENCES

1. Bray F, Ferlay J, Soerjomataram I, Siegel RL, Torre LA, Jemal A. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin 2018;68:394-424.

2. Liu X, Qin S. Immune Checkpoint Inhibitors in Hepatocellular Carcinoma: Opportunities and Challenges. Oncologist 2019;24:S3-10.

3. Montella L, Palmieri G, Addeo R, Del Prete S. Hepatocellular carcinoma: Will novel targeted drugs really impact the next future? World J Gastroenterol 2016;22:6114-26.

4. Kudo M. A new era of systemic therapy for hepatocellular carcinoma with Regorafenib and Lenvatinib. Liver Cancer 2017;6:177-84.

5. Wörns MA, Galle PR. HCC therapies--lessons learned. Nat Rev Gastroenterol Hepatol 2014;11:447-52.

6. Hernandez-Gea V, Toffanin S, Friedman SL, Llovet JM. Role of the microenvironment in the pathogenesis and treatment of hepatocellular carcinoma. Gastroenterology 2013;144:512-27.

7. Karin M. Nuclear factor-kappaB in cancer development and progression. Nature 2006;441:431-6.

8. Horst AK, Neumann K, Diehl L, Tiegs G. Modulation of liver tolerance by conventional and nonconventional antigen-presenting cells and regulatory immune cells. Cell Mol Immunol 2016;13:277-92.

9. Buonaguro L, Mauriello A, Cavalluzzo B, Petrizzo A, Tagliamonte M. Immunotherapy in hepatocellular carcinoma. Ann Hepatol 2019;18:291-7.

10. Jenne CN, Kubes P. Immune surveillance by the liver. Nat Immunol 2013;14:996-1006.

11. Racanelli V, Rehermann B. The liver as an immunological organ. Hepatology 2006;43:S54-62.

12. Shetty S, Lalor PF, Adams DH. Liver sinusoidal endothelial cells - gatekeepers of hepatic immunity. Nat Rev Gastroenterol Hepatol 2018;15:555-67.

13. Carambia A, Frenzel C, Bruns OT, et al. Inhibition of inflammatory CD4 T cell activity by murine liver sinusoidal endothelial cells. J Hepatol 2013;58:112-8.

14. Diehl L, Schurich A, Grochtmann R, Hegenbarth S, Chen L, Knolle PA. Tolerogenic maturation of liver sinusoidal endothelial cells promotes B7-homolog 1-dependent CD8+ T cell tolerance. Hepatology 2008;47:296-305.

15. Schildberg FA, Hegenbarth SI, Schumak B, Scholz K, Limmer A, Knolle PA. Liver sinusoidal endothelial cells veto CD8 T cell activation by antigen-presenting dendritic cells. Eur J Immunol 2008;38:957-67.

16. Dixon LJ, Barnes M, Tang H, Pritchard MT, Nagy LE. Kupffer cells in the liver. In: Terjung R, editor. Comprehensive physiology. Hoboken: John Wiley & Sons, Inc.; 2013.

17. Thomson AW, Knolle PA. Antigen-presenting cell function in the tolerogenic liver environment. Nat Rev Immunol 2010;10:753-66.

18. You Q, Cheng L, Kedl RM, Ju C. Mechanism of T cell tolerance induction by murine hepatic Kupffer cells. Hepatology 2008;48:978-90.

19. Ormandy LA, Hillemann T, Wedemeyer H, Manns MP, Greten TF, Korangy F. Increased populations of regulatory T cells in peripheral blood of patients with hepatocellular carcinoma. Cancer Res 2005;65:2457-64.

20. Dou L, Ono Y, Chen YF, Thomson AW, Chen XP. Hepatic dendritic cells, the tolerogenic liver environment, and liver disease. Semin Liver Dis 2018;38:170-80.

21. Severi T, van Malenstein H, Verslype C, van Pelt JF. Tumor initiation and progression in hepatocellular carcinoma: risk factors, classification, and therapeutic targets. Acta Pharmacol Sin 2010;31:1409-20.

22. Qin LX. Inflammatory immune responses in tumor microenvironment and metastasis of hepatocellular carcinoma. Cancer Microenviron 2012;5:203-9.

23. Cancer Genome Atlas Research Network. Cancer Genome Atlas Research Network. Comprehensive and integrative genomic characterization of hepatocellular carcinoma. Cell 2017;169:1327-41.e23.

24. Sia D, Jiao Y, Martinez-Quetglas I, et al. Identification of an immune-specific class of hepatocellular carcinoma, based on molecular features. Gastroenterology 2017;153:812-26.

25. Behboudi S, Boswell S, Williams R. Cell-mediated immune responses to alpha-fetoprotein and other antigens in hepatocellular carcinoma. Liver Int 2010;30:521-6.

26. Fu J, Xu D, Liu Z, et al. Increased regulatory T cells correlate with CD8 T-cell impairment and poor survival in hepatocellular carcinoma patients. Gastroenterology 2007;132:2328-39.

27. Yang YM, Kim SY, Seki E. Inflammation and liver cancer: molecular mechanisms and therapeutic targets. Semin Liver Dis 2019;39:26-42.

28. Liu CY, Chen KF, Chen PJ. Treatment of liver cancer. Cold Spring Harb Perspect Med 2015;5:a021535.

29. Jadid FZ, Chihab H, Alj HS, et al. Control of progression towards liver fibrosis and hepatocellular carcinoma by SOCS3 polymorphisms in chronic HCV-infected patients. Infect Genet Evol 2018;66:1-8.

30. Kudo M. Immuno-oncology in hepatocellular carcinoma: 2017 Update. Oncology 2017;93 Suppl 1:147-59.

31. Chuang W, Liu H, Chang W. Natural killer cell activity in patients with hepatocellular carcinoma relative to early development and tumor invasion. Cancer 1990;65:926-30.

32. Wu Y, Kuang DM, Pan WD, et al. Monocyte/macrophage-elicited natural killer cell dysfunction in hepatocellular carcinoma is mediated by CD48/2B4 interactions. Hepatology 2013;57:1107-16.

33. Abril-Rodriguez G, Ribas A. SnapShot: immune checkpoint inhibitors. Cancer Cell 2017;31:848.e1.

34. Chen G, Huang AC, Zhang W, et al. Exosomal PD-L1 contributes to immunosuppression and is associated with anti-PD-1 response. Nature 2018;560:382-6.

35. Robert C, Long GV, Brady B, et al. Nivolumab in previously untreated melanoma without BRAF mutation. N Engl J Med 2015;372:320-30.

36. El-khoueiry AB, Sangro B, Yau T, et al. Nivolumab in patients with advanced hepatocellular carcinoma (CheckMate 040): an open-label, non-comparative, phase 1/2 dose escalation and expansion trial. Lancet 2017;389:2492-502.

37. Zhu AX, Finn RS, Edeline J, et al. Pembrolizumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib (KEYNOTE-224): a non-randomised, open-label phase 2 trial. Lancet Oncol 2018;19:940-52.

38. Kudo M. Molecular targeted therapy for hepatocellular carcinoma: where are we now? Liver Cancer 2015;4:I-VII.

39. Zhang B, Finn RS. Personalized clinical trials in hepatocellular carcinoma based on biomarker selection. Liver Cancer 2016;5:221-32.

40. Bruix J, Qin S, Merle P, et al. Regorafenib for patients with hepatocellular carcinoma who progressed on sorafenib treatment (RESORCE): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet 2017;389:56-66.

41. Yoo C, Park JW, Kim YJ, et al. Multicenter retrospective analysis of the safety and efficacy of regorafenib after progression on sorafenib in Korean patients with hepatocellular carcinoma. Invest New Drugs 2019;37:567-72.

42. Yoo C, Ryu YM, Kim SY, et al. Association between the exposure to anti-angiogenic agents and tumour immune microenvironment in advanced gastrointestinal stromal tumours. Br J Cancer 2019;121:819-26.

43. Titano J, Noor A, Kim E. Transarterial chemoembolization and radioembolization across barcelona clinic liver cancer stages. Semin Intervent Radiol 2017;34:109-15.

44. Bolondi L, Burroughs A, Dufour JF, et al. Heterogeneity of patients with intermediate (BCLC B) hepatocellular carcinoma: proposal for a subclassification to facilitate treatment decisions. Semin Liver Dis 2012;32:348-59.

45. El-Khoueiry AB, Sangro B, Yau T, et al. Nivolumab in patients with advanced hepatocellular carcinoma (CheckMate 040): an open-label, non-comparative, phase 1/2 dose escalation and expansion trial. Lancet 2017;389:2492-502.

46. Yau T, Hsu C, Kim TY, et al. Nivolumab in advanced hepatocellular carcinoma: sorafenib-experienced Asian cohort analysis. J Hepatol 2019;71:543-52.

47. Lichty BD, Breitbach CJ, Stojdl DF, Bell JC. Going viral with cancer immunotherapy. Nat Rev Cancer 2014;14:559-67.

48. Guo ZS, Thorne SH, Bartlett DL. Oncolytic virotherapy: molecular targets in tumor-selective replication and carrier cell-mediated delivery of oncolytic viruses. Biochim Biophys Acta 2008;1785:217-31.

49. Akira S, Takeda K, Kaisho T. Toll-like receptors: critical proteins linking innate and acquired immunity. Nat Immunol 2001;2:675-80.

50. Kato H, Takeuchi O, Sato S, et al. Differential roles of MDA5 and RIG-I helicases in the recognition of RNA viruses. Nature 2006;441:101-5.

51. Kaufman HL, Kohlhapp FJ, Zloza A. Oncolytic viruses: a new class of immunotherapy drugs. Nat Rev Drug Discov 2015;14:642-62.

52. Yoo SY, Badrinath N, Woo HY, Heo J. Oncolytic virus-based immunotherapies for hepatocellular carcinoma. Mediators Inflamm 2017;2017:5198798.

53. Kanerva A, Nokisalmi P, Diaconu I, et al. Antiviral and antitumor T-cell immunity in patients treated with GM-CSF-coding oncolytic adenovirus. Clin Cancer Res 2013;19:2734-44.

54. Kirn DH, Thorne SH. Targeted and armed oncolytic poxviruses: a novel multi-mechanistic therapeutic class for cancer. Nat Rev Cancer 2009;9:64-71.

55. Abdullahi S, Jäkel M, Behrend SJ, et al. A novel chimeric oncolytic virus vector for improved safety and efficacy as a platform for the treatment of hepatocellular carcinoma. J Virol 2018;92:e01386-18.

56. Zhang H, Li K, Lin Y, et al. Targeting VCP enhances anticancer activity of oncolytic virus M1 in hepatocellular carcinoma. Sci Transl Med 2017;9:eaam7996.

57. Luo Y, Lin C, Ren W, et al. Intravenous injections of a rationally selected oncolytic herpes virus as a potent virotherapy for hepatocellular carcinoma. Mol Ther Oncolytics 2019;15:153-65.

58. Chen A, Zhang Y, Meng G, et al. Oncolytic measles virus enhances antitumour responses of adoptive CD8(+)NKG2D(+) cells in hepatocellular carcinoma treatment. Sci Rep 2017;7:5170.

59. Xie W, Hao J, Zhang K, et al. Adenovirus armed with VGLL4 selectively kills hepatocellular carcinoma with G2/M phase arrest and apoptosis promotion. Biochem Biophys Res Commun 2018;503:2758-63.

60. Nakatake R, Kaibori M, Nakamura Y, et al. Third-generation oncolytic herpes simplex virus inhibits the growth of liver tumors in mice. Cancer Sci 2018;109:600-10.

61. El-Shemi AG, Ashshi AM, Oh E, et al. Efficacy of combining ING4 and TRAIL genes in cancer-targeting gene virotherapy strategy: first evidence in preclinical hepatocellular carcinoma. Gene Ther 2018;25:54-65.

62. Zhang J, Lai W, Li Q, et al. A novel oncolytic adenovirus targeting Wnt signaling effectively inhibits cancer-stem like cell growth via metastasis, apoptosis and autophagy in HCC models. Biochem Biophys Res Commun 2017;491:469-77.

63. Lv SQ, Ye ZL, Liu PY, et al. 11R-P53 and GM-CSF expressing oncolytic adenovirus target cancer stem cells with enhanced synergistic activity. J Cancer 2017;8:199-206.

64. El-Shemi AG, Ashshi AM, Na Y, et al. Combined therapy with oncolytic adenoviruses encoding TRAIL and IL-12 genes markedly suppressed human hepatocellular carcinoma both in vitro and in an orthotopic transplanted mouse model. J Exp Clin Cancer Res 2016;35:74.

65. Ruf B, Berchtold S, Venturelli S, et al. Combination of the oral histone deacetylase inhibitor resminostat with oncolytic measles vaccine virus as a new option for epi-virotherapeutic treatment of hepatocellular carcinoma. Mol Ther Oncolytics 2015;2:15019.

66. Ady JW, Johnsen C, Mojica K, Heffner J, Love D, et al. Oncolytic gene therapy with recombinant vaccinia strain GLV-2b372 efficiently kills hepatocellular carcinoma. Surgery 2015;158:331-8.

67. Ady JW, Heffner J, Mojica K, et al. Oncolytic immunotherapy using recombinant vaccinia virus GLV-1h68 kills sorafenib-resistant hepatocellular carcinoma efficiently. Surgery 2014;156:263-9.

68. Lin WH, Yeh SH, Yang WJ, et al. Telomerase-specific oncolytic adenoviral therapy for orthotopic hepatocellular carcinoma in HBx transgenic mice. Int J Cancer 2013;132:1451-62.

69. Wang J, Xu L, Zeng W, et al. Treatment of human hepatocellular carcinoma by the oncolytic herpes simplex virus G47delta. Cancer Cell Int 2014;14:83.

70. Fu X, Rivera A, Tao L, et al. Construction of an oncolytic herpes simplex virus that precisely targets hepatocellular carcinoma cells. Mol Ther 2012;20:339-46.

71. Gentschev I, Müller M, Adelfinger M, et al. Efficient colonization and therapy of human hepatocellular carcinoma (HCC) using the oncolytic vaccinia virus strain GLV-1h68. PLoS One 2011;6:e22069.

72. Jin H, Lv S, Yang J, et al. Use of microRNA Let-7 to control the replication specificity of oncolytic adenovirus in hepatocellular carcinoma cells. PLoS One 2011;6:e21307.

73. Lee JH, Roh MS, Lee YK, et al. Oncolytic and immunostimulatory efficacy of a targeted oncolytic poxvirus expressing human GM-CSF following intravenous administration in a rabbit tumor model. Cancer Gene Ther 2010;17:73-9.

74. Wein LM, Wu JT, Kirn DH. Validation and analysis of a mathematical model of a replication-competent oncolytic virus for cancer treatment: implications for virus design and delivery. Cancer Res 2003;63:1317-24.

75. Thorne SH, Hwang TH, O’Gorman WE, et al. Rational strain selection and engineering creates a broad-spectrum, systemically effective oncolytic poxvirus, JX-963. J Clin Invest 2007;117:3350-8.

76. Kim JH, Oh JY, Park BH, et al. Systemic armed oncolytic and immunologic therapy for cancer with JX-594, a targeted poxvirus expressing GM-CSF. Mol Ther 2006;14:361-70.

77. Parato KA, Breitbach CJ, Le Boeuf F, et al. The oncolytic poxvirus JX-594 selectively replicates in and destroys cancer cells driven by genetic pathways commonly activated in cancers. Mol Ther 2012;20:749-58.

78. Park B, Hwang T, Liu T, et al. Use of a targeted oncolytic poxvirus, JX-594, in patients with refractory primary or metastatic liver cancer: a phase I trial. Lancet Oncology 2008;9:533-42.

79. Heo J, Reid T, Ruo L, et al. Randomized dose-finding clinical trial of oncolytic immunotherapeutic vaccinia JX-594 in liver cancer. Nat Med 2013;19:329-36.

80. Moehler M, Heo J, Lee HC, et al. Vaccinia-based oncolytic immunotherapy pexastimogene devacirepvec in patients with advanced hepatocellular carcinoma after sorafenib failure: a randomized multicenter Phase IIb trial (TRAVERSE). Oncoimmunology 2019;8:1615817.

81. Heo J, Reid T, Ruo L, et al. Randomized dose-finding clinical trial of oncolytic immunotherapeutic vaccinia JX-594 in liver cancer. Nat Med 2013;19:329-36.

82. Moehler M, Heo J, Lee HC, et al. Vaccinia-based oncolytic immunotherapy Pexastimogene Devacirepvec in patients with advanced hepatocellular carcinoma after sorafenib failure: a randomized multicenter Phase IIb trial (TRAVERSE). Oncoimmunology 2019;8:1615817.

83. Park BH, Hwang T, Liu TC, et al. Use of a targeted oncolytic poxvirus, JX-594, in patients with refractory primary or metastatic liver cancer: a phase I trial. Lancet Oncol 2008;9:533-42.

84. Rizell M, Eilard MS, Andersson M, et al. Phase 1 trial with the cell-based immune primer ilixadencel, alone, and combined with sorafenib, in advanced hepatocellular carcinoma. Front Oncol 2019;9:19.

85. Ning N, Pan Q, Zheng F, et al. Cancer stem cell vaccination confers significant antitumor immunity. Cancer Res 2012;7:1853-64.

86. Johnston MP, Khakoo SI. Immunotherapy for hepatocellular carcinoma: current and future. World J Gastroenterol 2019;25:2977-89.

87. Gustafsson K, Ingelsten M, Bergqvist L, Nyström J, Andersson B, Karlsson-Parra A. Recruitment and activation of natural killer cells in vitro by a human dendritic cell vaccine. Cancer Res 2008;68:5965-71.

88. Shang N, Figini M, Shangguan J, et al. Dendritic cells based immunotherapy. Am J Cancer Res 2017;7:2091-102.

89. Rizell M, Sternby Eilard M, Andersson M, Andersson B, Karlsson-Parra A, Suenaert P. Phase 1 trial with the cell-based immune primer ilixadencel, alone, and combined with sorafenib, in advanced hepatocellular carcinoma. Front Oncol 2019;9:19.

90. Jena B, Dotti G, Cooper LJ. Redirecting T-cell specificity by introducing a tumor-specific chimeric antigen receptor. Blood 2010;116:1035-44.

91. Jiang Z, Jiang X, Chen S, et al. Anti-GPC3-CAR T cells suppress the growth of tumor cells in patient-derived xenografts of hepatocellular carcinoma. Front Immunol 2016;7:690.

92. Wang Y, Chen M, Wu Z, et al. CD133-directed CAR T cells for advanced metastasis malignancies: a phase I trial. Oncoimmunology 2018;7:e1440169.

93. Li D, Li N, Zhang YF, et al. Persistent polyfunctional chimeric antigen receptor T cells that target glypican 3 eliminate orthotopic hepatocellular carcinomas in mice. Gastroenterology 2020;158:2250-65.e20.

94. Liu X, Wen J, Yi H, et al. Split chimeric antigen receptor-modified T cells targeting glypican-3 suppress hepatocellular carcinoma growth with reduced cytokine release. Ther Adv Med Oncol 2020;12:1758835920910347.

95. Sun B, Yang D, Dai H, et al. Eradication of hepatocellular carcinoma by NKG2D-based CAR-T cells. Cancer Immunol Res 2019;7:1813-23.

96. Zhang RY, Wei D, Liu ZK, et al. Doxycycline inducible chimeric antigen receptor T cells targeting CD147 for hepatocellular carcinoma therapy. Front Cell Dev Biol 2019;7:233.

97. Morgan RA, Johnson LA, Davis JL, et al. Recognition of glioma stem cells by genetically modified T cells targeting EGFRvIII and development of adoptive cell therapy for glioma. Hum Gene Ther 2012;23:1043-53.

98. Finney HM, Akbar AN, Lawson AD. Activation of resting human primary T cells with chimeric receptors: costimulation from CD28, inducible costimulator, CD134, and CD137 in series with signals from the TCR zeta chain. J Immunol 2004;172:104-13.

99. Yau T, Kang YK, Kim TY, et al. Efficacy and safety of Nivolumab plus Ipilimumab in patients with advanced hepatocellular carcinoma previously treated with Sorafenib: the CheckMate 040 randomized clinical trial. JAMA Oncol 2020;e204564.

100. Finn RS, Qin S, Ikeda M, et al; IMbrave150 Investigators. Atezolizumab plus Bevacizumab in Unresectable Hepatocellular Carcinoma. N Engl J Med 2020;382:1894-905.

Cite This Article

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Open Access
The immune microenvironment and progression of immunotherapy and combination therapeutic strategies for hepatocellular carcinoma
Zun-Yong Feng, ... Hong-Ping Xia

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Feng, Z. Y.; Xu F. G.; Liu Y.; Xu H. J.; Wu F. B.; Chen X. B.; Xia H. P. The immune microenvironment and progression of immunotherapy and combination therapeutic strategies for hepatocellular carcinoma. Hepatoma. Res. 2021, 7, 3. http://dx.doi.org/10.20517/2394-5079.2020.107

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ISSN 2454-2520 (Online) 2394-5079 (Print)

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